Dataset in SPSS and CSV format for Study 1 and Study 2 described in the manuscript with the above title

A predominant expectation that social relationships with others are safe (a secure attachment style), has been linked with reduced threat-related amygdala activation. Experimental priming of mental representations of attachment security can modulate neural responding, but the effects of attachment-security priming on threat-related amygdala activation remains untested. Using functional magnetic resonance imaging, the present study examined the effects of trait and primed attachment security on amygdala reactivity to threatening stimuli in an emotional faces and a linguistic dot-probe task in 42 healthy participants. Trait attachment anxiety and attachment avoidance were positively correlated with amygdala activation to threatening faces in the control group, but not in the attachment primed group. Furthermore, participants who received attachment-security priming showed attenuated amygdala activation in both the emotional faces and dot-probe tasks. The current findings demonstrate that variation in state and trait attachment security modulates amygdala reactivity to threat. These findings support the potential use of attachment security-boosting methods as interventions and suggest a neural mechanism for the protective effect of social bonds in anxiety disorders.

Overeating in our food-rich environment is a key contributor to obesity. Computerised response-inhibition training could improve self-control in individuals who overeat. Evidence suggests that training people to inhibit motor responses to specific food pictures can reduce the subsequent choice and consumption of those foods. Here we undertook three experiments using the stop-signal task to examine the effects of food and non-food related stop-training on immediate snack food consumption. The experiments examined whether training effects were stimulus-specific, whether they were influenced by the comparator (control) group, and whether they were moderated by individual differences in dietary restraint. Experiment 1 revealed lower intake of one food following stop- vs. double- (two key-presses) response training to food pictures. Experiment 2 offered two foods, one of which was not associated with stopping, to enable within- and between-subjects comparisons of intake. A second control condition required participants to ignore signals and respond with one key-press to all pictures. There was no overall effect of training on intake in Experiment 2, but there was a marginally significant moderation by dietary restraint: Restrained eaters ate significantly less signal-food following stop- relative to double-response training. Experiment 3 revealed that stop- vs. double-response training to non-food pictures had no effect on food intake. Taken together with previous findings, these results suggest some stimulus-specific effects of stop-training on food intake that may be moderated by individual differences in dietary restraint.

The majority of adults in the UK and US are overweight or obese due to multiple factors including excess energy intake. Training people to inhibit simple motor responses (key presses) to high-energy density food pictures reduces intake in laboratory studies. We examined whether online response inhibition training reduced real-world food consumption and weight in a community sample of adults who were predominantly overweight or obese (N = 83). Participants were allocated in a randomised, double-blind design to receive four 10-min sessions of either active or control go/no-go training in which either high-energy density snack foods (active) or non-food stimuli (control) were associated with no-go signals. Participants' weight, energy intake (calculated from 24-h food diaries), daily snacking frequency and subjective food evaluations were measured for one week pre- and post-intervention. Participants also provided self-reported weight and monthly snacking frequency at pre-intervention screening, and one month and six months after completing the study. Participants in the active relative to control condition showed significant weight loss, reductions in daily energy intake and a reduction in rated liking of high-energy density (no-go) foods from the pre-to post-intervention week. There were no changes in self-reported daily snacking frequency. At longer-term follow-up, the active group showed significant reductions in self-reported weight at six months, whilst both groups reported significantly less snacking at one- and six-months. Excellent rates of adherence (97%) and positive feedback about the training suggest that this intervention is acceptable and has the potential to improve public health by reducing energy intake and overweight.

In slot machine gambling, the "near-miss effect" (when a losing display physically resembles an actual win display) has been implicated in pathological gambling (PG). Functional magnetic resonance imaging (fMRI) with PG and non-PG participants shows that near-misses recruit reward-related circuitry, but little is known about the temporal dynamics and oscillatory changes underlying near-misses. The present multi-modal imaging study investigated the near-miss effect by combining the spatial resolution of blood oxygen-level dependent (BOLD)-fMRI with the spatial and temporal resolution of magnetoencephalography (MEG) during a slot machine task in PG and non-PG groups. Given previous findings on outcome (win and near-miss) processing, functional overlap was hypothesized between induced changes in temporal oscillations and BOLD response to wins and near-misses in PG. We first validated our task in a sample of varying gambling severity using BOLD-fMRI and then compared PG and non-PG participants using MEG to investigate changes in induced oscillatory power associated with win and near-miss, relative to loss, outcomes. Across both modalities, near-misses recruited similar brain regions to wins, including right inferior frontal gyrus and insula. Using MEG, increased theta-band (4-7Hz) oscillations to near-misses were observed in the insula and right orbitofrontal cortex (OFC). Furthermore, this theta-band activity was positively associated with gambling severity. These findings demonstrate that the near-miss effect in insula and OFC is associated with induced theta oscillations. The significance of these findings for theories of PG and the development of potential biomarkers and therapeutic targets is discussed.

OBJECTIVE: Little is known about the neurobiology of bipolar II disorder. While bipolar I disorder is associated with abnormally elevated activity in response to reward in the ventral striatum, a key component of reward circuitry, no studies have compared reward circuitry function in bipolar I and bipolar II disorders. Furthermore, associations among reward circuitry activity, reward sensitivity, and striatal volume remain underexplored in bipolar and healthy individuals. The authors examined reward activity in the ventral striatum in participants with bipolar I and II disorders and healthy individuals, the relationships between ventral striatal activity and reward sensitivity across all participants, and between-group differences in striatal gray matter volume and relationships with ventral striatal activity across all participants. METHOD: Twenty healthy comparison subjects and 32 euthymic bipolar I (N=17) and bipolar II (N=15) patients underwent a neuroimaging reward paradigm during functional MRI scanning, structural scanning, and completed psychometric and clinical assessments. RESULTS: Region-of-interest analyses revealed significant ventral striatal activity in all participants during reward anticipation that was significantly greater in bipolar II patients compared with the other groups. Ventral striatal activity during reward anticipation correlated positively with reward sensitivity and fun seeking across all participants. Bipolar II patients had significantly greater left putamen volume than bipolar I patients, and left putamen volume correlated positively with left ventral striatal activity to reward anticipation in all participants. CONCLUSIONS: Abnormally elevated ventral striatal activity during reward anticipation may be a potential biomarker of bipolar II disorder. These findings highlight the importance of adopting a dimensional approach in the study of neural mechanisms supporting key pathophysiological processes that may cut across psychiatric disorders.

. Background
. A multidisciplinary approach to weight management is offered at tier 3 pediatric weight management services in the United Kingdom. Encouraging dietary change is a major aim, with patients meeting with dieticians, endocrinologists, psychologists, nurse specialists, and social workers on average every other month.
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.
. Objective
. This research sought to trial an inhibitory control training smartphone app—FoodT—with the clinic population of a pediatric weight management service. FoodT has shown positive impacts on food choice in adult users, with resulting weight loss. It was hoped that when delivered as an adjunctive treatment alongside the extensive social, medical, psychological, and dietetic interventions already offered at the clinic, the introduction of inhibitory control training may offer patients another tool that supports eating choice. In this feasibility trial, recruitment, retention, and app use were the primary outcomes. An extensive battery of measures was included to test the feasibility and acceptability of these measures for future powered trials.
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. Methods
. FoodT was offered to pediatric patients and their parents during a routine clinic appointment, and patients were asked to use the app at home every day for the first week and once per week for the rest of the month. Feasibility and acceptability were measured in terms of recruitment, engagement with the app, and retention to the trial. A battery of psychometric tests was given before and after app use to assess the acceptability of collecting data on changes to food choices and experiences that would inform future trial work.
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.
. Results
. A total of 12 children and 10 parents consented (22/62, 35% of those approached). Further, 1 child and no parents achieved the recommended training schedule. No participants completed the posttrial measures. The reasons for not wanting to be recruited to the trial included participants not considering their weight to be connected to eating choices and not feeling that the app suited their needs. No reasons are known for noncompletion.
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.
. Conclusions
. It is unclear whether the intervention itself or the research processes, including the battery of measures, prevented completion. It is therefore difficult to make any decisions as to the value that the app has within this setting. Important lessons have been learned from this research that have potential broad relevance, including the importance of co-designing interventions with service users and avoiding deterring people from early-stage participation in extensive data collection.
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In 2014, author and speaker Tom Asacker presented the popular TED talk entitled “Why TED Talks don't change people's behaviors”—arguing that lasting behavioural change is only truly achievable by appealing to an individual’s identity and self-concept. His message, that “who we think we are, is why we do what we do” is fundamental to Social Identity Theory (Tajfel, 1978; Tajfel & Turner, 1979, 1986)—which posits that we derive an essential part of our self-concept from our group memberships. Rather than being external to the self, our group memberships and their content—including the consensual perceptions of what is normative for a given group—are internalised within the self-concept in the form of social identities (Tajfel, 1981; Turner, 1982, 1985). Properties of the social group, such as group norms, become subjectively interchangeable with personal norms and stereotypes—influencing thought and guiding action. Our social identities therefore provide some insight into who we are, what we think, and what we do (Abrams et al. 1990; Oakes et al. 1994; Reicher, 2001). Social identities are not only important in describing where we sit within our perceived social reality, but also in predicting what we will become; identities have the power to shape and change our future behaviour (Reicher, 2001).

Implicit in both this messaging and social identity theorising is the suggestion that this relationship between social identity and behaviour may not be so straight forward; while it is true who we think we are contributes to how we behave, equally, the way we behave—and the extent to which it is seen to be normative for a given group—guides the groups we identify with. Therefore, our behaviour has implications for our self-concept. The acquisition of self-knowledge in this fashion is fundamental to theories of cognitive consistency—such as self-perception theory (Bem, 1972)—which posit that individuals infer their own attitudes, beliefs, and other internal states from observing their own behaviours and the circumstances under which they occur (Bem, 1972). For example, when a university student repeatedly engages in behaviours seen to be normative of the student identity—such as drinking (Davoren et al. 2016; John & Alwyn, 2014)—they may begin to reflect on this congruency between their own behaviour and the behaviour of other students. Over time, this individual may begin to identify more strongly as a student, as they perceive their behaviour to align with what it means to be a student. Failing to engage in such behaviours might (over time) even lead to disidentification from the group. This reciprocal causality is consistent with theories and research that examine the wider associative network of the self-concept (Greenwald & Pratkanis, 1984; Koffka, 1935), and has been modelled in relation to other social psychological constructs such a attitudes and self-esteem (e.g. the balanced identity design; Greenwald, Banaji, Rudman, et al. 2002, Dunham, 2013).

While traditional and contemporary theories of social identity have focused primarily on different bivariate relationships among social identity, group norms and behaviour, these relationships are yet to be unified in a single, dynamic model that theorises how the interrelations among these self-relevant constructs emerge and are maintained. This thesis presents, and comprehensively tests, a Social Identity Model of Behavioural Associations (SIMBA)—a theoretical and methodological integration of both social (Tajfel, 1978; Tajfel & Turner, 1979; Turner et al. 1987) and balanced identity theorising (Greenwald, Banaji, Rudman, et al. 2002)—which models the relationships among social identification, group norms, and individual-level behaviour as reciprocal associative links in a triangular constellation.

Throughout the thesis, the SIMBA is used explore two overarching research questions. First, we determine whether identity, norms, and behaviour can be measured—not only directly (i.e. via self-report), but also indirectly (i.e. via implicit measures) as cognitive associations among self-group, group-behaviour, and self-behaviour concepts. We also establish whether the three constructs demonstrate a mutually interactive relationship; that is, whether any one of the constructs may be explained by the interaction between the remaining two. Second, we aim to demonstrate reciprocal causality; beyond describing interactive relations among concepts, the SIMBA assumes that each construct is not only explained, but predicted by the remaining two. Therefore, we explore the cognitive processes through which identity, norms and behaviour are created, and determine whether cognitive balance emerges among them. Ultimately, the thesis tests the utility of the SIMBA as a theoretical framework for understanding the relation between, and the formation of, social identity, group norms, and individual-level behaviour.

In Chapter 1, we review the relevant theories that underpin the theoretical and methodological assumptions of the SIMBA, that is, the theories relevant to the social identity approach (i.e. social identity theory and self-categorisation theory) and cognitive consistency (i.e. balance theory and balanced identity theory). These theories are discussed in terms of their origins and fundamental principles, while also highlighting the ways in which they have inspired and contributed to the development of contemporary theories in their respective fields. With regards to the social identity approach, we discuss how traditional social identity theorising has advanced through the development of models that consider social identity and group norms to be mutually interactive and influential in the formation of one another. Regarding theories of cognitive consistency, we discuss the way in which these theories have become increasingly broad in their applicability and explanatory potential—explaining cognitive balance in a variety of contexts such as interpersonal relations, social identity, and intergroup attitudes.

In Chapter 2, we provide a theoretical overview of the SIMBA. The theory’s key predictions regarding measuring associations, creating associations, and changing associations are outlined, alongside the supporting literature that aided in their development. This chapter also discusses the ways in which the SIMBA theoretically and methodologically advances both SIT and BIT by drawing direct comparisons between the theories. This chapter ends with an overview of the thesis, which highlights the specific research questions that will be addressed in each empirical chapter, and the progression of ideas across chapters.

Chapters 3 and 4 focus on testing the utility of the SIMBA for the measurement of self-group-behaviour associations. Across these chapters, we investigate the primary assumption of the SIMBA (i.e. the balance-congruity principle; that the strength of any one association in the SIMBA can be predicted by the interactive strength of the remaining two) in relation to a variety of group memberships and behaviours—establishing the generalisability of the SIMBA.

In Chapter 3, we tested the SIMBA in the context of drinking behaviour in relation to student (Studies 1 and 2) and British national (Study 3) identities. These studies identified good support for the balance-congruity principle on implicit measures of social identity, group norms, and behaviour. Evidence for this prediction was weaker on explicit scale measures; we argue that this difference may be dependent on the explicit measures possessing theoretically meaningful zero-points.

In Chapter 4, we tested the SIMBA in the context of social distancing behaviour in relation to the British national identity. Study 4 included two different types of explicit measure (e.g. traditional Likert-type scales and visual analogue scales); confirming that support on explicit measures was strong, and equal to that on implicit measures, when using visual analogue scales (i.e. measures that possess a zero-point indicative of associative indifference). We also assessed balance-congruity across two timepoints during the COVID-19 pandemic—finding cognitive balance to be stable over time.

In Chapter 5, we step back from directly testing the assumptions of the SIMBA and adopt a network analytic approach to understanding the different social identities found to co-occur within individuals, and the behaviours thought to correspond with specific identities. This research was initially developed to help identify associated groups and behaviours to feature in future tests of the SIMBA—particularly for the measurement of associations, following on from Chapters 3 and 4—but the co-occurrences identified also serve as a meaningful resource for those conducting research into identities and their associated behaviours more generally. Therefore, while the chapter may appear to divert from the SIMBA narrative, it has an important function in progressing the theory (e.g. establishing its wider generalisability to multiple groups and behaviours), and social identity research more broadly. In Study 5, we generated three different network-types—identity-by-identity, behaviour-by-identity, and identity-by-behaviour—where we identified several identities and behaviours to significantly co-occur at a rate both higher and lower than chance. Although the overall structure of the networks was found to be significantly different than expected by chance, networks were low in modularity (i.e. there was no evidence of clustering within the data).

In the final empirical chapter (i.e. Chapter 6) we focus on testing the utility of the SIMBA for the creation of novel self-group-behaviour associations. In two pilot studies, we established the initial efficacy of both the partial-IAT and probabilistic learning tasks for generating associations among concepts. After refining these methodologies, Study 6 directly compared them, and conducted an experimental test of the balance-congruity principle. While being equivalent to the probabilistic learning methodology in its ability to create self-group-behaviour associations, and generate balance-congruity among explicit associations, the partial-IAT was less effective in generating balance-congruity among implicit associations. We therefore find the probabilistic learning methodology to be the most appropriate of the two. Study 7 then examines changes in associative strength across three timepoints—finding associations to be stable across time, irrespective of whether participants were exposed to a ‘booster session’ of the probabilistic learning manipulation.

In Chapter 7, we discuss all of the empirical results taken together. We synthesise, and evaluate, the strength of evidence in relation to the four key predictions of the SIMBA outlined in Chapter 2. We also discuss the key theoretical and methodological contribution of our research, while acknowledging some of the limitations that persist across empirical chapters. Finally, we discuss avenues for future research regarding the use of the SIMBA not only for the measurement and creation of self-group-behaviour associations, but also as a framework for changing associations. In doing so, we highlight some of the practical implications of the model.

Abstract
.
. Background
. The mechanisms underlying genetic predisposition to higher body mass index (BMI) remain unclear.
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. Methods
. We hypothesized that the relationship between BMI-genetic risk score (BMI-GRS) and BMI was mediated via disinhibition, emotional eating and hunger, and moderated by flexible (but not rigid) restraint within two UK cohorts: the Genetics of Appetite Study (GATE) (n = 2101, 2010–16) and the Avon Longitudinal Study of Parents and Children (ALSPAC) (n = 1679, 2014–18). Eating behaviour was measured by the Adult Eating Behaviour Questionnaire and Three-Factor Eating Questionaire-51.
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.
. Results
. The association between BMI-GRS and BMI were partially mediated by habitual, emotional and situational disinhibition in the GATE/ALSPAC meta-mediation [standardized betaindirect 0.04, 95% confidence interval (CI) 0.02–0.06; 0.03, 0.01–0.04; 0.03, 0.01–0.04, respectively] external hunger and internal hunger in the GATE study (0.02, 0.01–0.03; 0.01, 0.001–0.02, respectively). There was evidence of mediation by emotional over/undereating and hunger in the ALSPAC study (0.02, 0.01–0.03; 0.01, 0.001–0.02; 0.01, 0.002–0.01, respectively). Rigid or flexible restraint did not moderate the direct association between BMI-GRS and BMI, but high flexible restraint moderated the effect of disinhibition subscales on BMI (reduction of the indirect mediation by -5% to -11% in GATE/ALSPAC) and external hunger (-5%) in GATE. High rigid restraint reduced the mediation via disinhibition subscales in GATE/ALSPAC (-4% to -11%) and external hunger (-3%) in GATE.
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. Conclusions
. Genetic predisposition to a higher BMI was partly explained by disinhibition and hunger in two large cohorts. Flexible/rigid restraint may play an important role in moderating the impact of predisposition to higher BMI.
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Meat is consistently the most highly valued food across most cultures, and is overconsumed in high income countries, driving declines in planetary and human health. Simultaneously, meat is also frequently an object of food taboos and feelings of disgust. Meat disgust has been studied in vegetarians in the past but may not be limited to meat avoiders and could potentially be used as a basis for interventions to reduce meat consumption. However, meat disgust and the mechanisms that may link it to meat avoidance are not well understood. This thesis aims to further our understanding of meat disgust by offering contributions to theory, evidence, and methodology. The current state of meat disgust research is reviewed in Chapter One, followed by four studies that investigate the concept of meat disgust in meat-eating and meat-avoiding populations. Chapter Two presents findings from a cross-sectional and longitudinal study in a sample of vegetarians, flexitarians, and omnivores that assessed meat disgust and meat intake over time and found that many vegetarians, as well as some flexitarians and omnivores, experience meat disgust, and that this affects levels of meat intake in meat-eating groups. Chapter Three compares meat disgust to similar food rejection responses towards plant-based foods and finds that meat, as opposed to disliked plant foods is a potent elicitor of core disgust. In Chapter Four, a quasi-experimental longitudinal study is presented that observed increases in meat disgust in a small sample of meat eaters following their attempts to avoid meat for one month during ‘Veganuary’. Here, a new theory of the causal relationship between meat disgust and meat avoidance is presented, that proposes disgust as the default response to meat which can be suppressed to allow the consumption of some meat. This theory is further tested in Chapter Five which presents a mega analysis of data on general disgust sensitivity and meat consumption collected in the three previous chapters, showing that any differences in disgust sensitivity across diet groups or effects on meat intake can be explained by demographic covariates and thereby supporting the theory that meat intake and may be de-coupled from disgust sensitivity via a suppression mechanism. Chapter Six embeds the findings on meat disgust from within this thesis with others’ findings and tests the newly proposed ‘suppression theory’ against two other, existing theories with regards to how well all of the findings can
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be explained. Additionally, the four different methodologies that were used in this thesis to study meat disgust are reviewed in Chapter Six, and recommendations for future studies in this field are made.

Background: the available treatments for people with excess weight have shown small effects. Cognitive training has shown promising results, but most of the research focused on normal-weight university students and reported immediate results after a single training session. This parallel group, randomized, controlled trial aims to study the efficacy of a program for the comprehensive cognitive treatment of excess weight. Methods and Analysis: Participants will be 150 people with excess weight recruited through social media, who will be randomized into three groups: cognitive intervention, sham cognitive intervention, and treatment as usual. All assessment and intervention sessions will be online in groups of 5–6 participants. The three groups will attend a motivational interviewing session, and they will receive individualized diet and physical exercise guidelines throughout the program. The cognitive training will consist of four weekly sessions of approximately 60–90 min, each based on approach–avoidance bias training, inhibitory control training, implementation of intentions, and episodic future thinking, respectively. The main outcome measure will be a change in Body Mass Index (kg/m2). Secondary outcomes include changes in cognitive measures, eating and physical exercise behaviors, and anthropometric measures. Assessments will be conducted up to 6 months after the end of the program. In addition, data on the use of the health system will be collected to analyze the cost-effectiveness and the cost-utility of training. Linear mixed models will be used for statistical analysis. Findings of this study will expand the available evidence on cognitive interventions to reduce excess weight.

PURPOSE: the aim of this study was to expand the evidence on the feasibility and impact of food-specific inhibitory control training in a community sample of people with disinhibited eating. METHODS: Recruitment and data collection were conducted during the COVID-19 outbreak, in Italy. Ninety-four adult individuals with disinhibited eating were randomised to one of two conditions: App-based food-specific inhibitory control training or waiting list. Participants were assessed at baseline, end of intervention (2 weeks following baseline) and follow-up (one week later). The assessment measures included questionnaires about eating behaviour and mood. RESULTS: Seventy-three percent of the sample reported a diagnosis of binge eating disorder, and 20.4% a diagnosis of bulimia nervosa. Retention rates were 77% and 86% for the food-specific inhibitory control training and the waiting list conditions, respectively. Almost half of the participants allocated to the training condition completed the "recommended" dose of training (i.e. 10 or more sessions). Those in the training condition reported lower levels of wanting for high-energy dense foods (p 

Background
The healthiness of children’s diets, and the success of interventions seeking to improve them, are hindered by children’s preferences for foods high in fat, salt and/or sugar over healthier options such as fruit and vegetables. Children’s food choices are often driven by hedonic factors such as taste rather than considerations of health and nutrition, meaning that educational approaches are unlikely to be successful on their own. Food Go/No-Go training (which sits in the family of motor response training and inhibition training tasks) is a computerised intervention that appears to target the automatic processes driving food choice (e.g. food liking/reward responses, and automatic motor responses) by requiring participants to inhibit their responses to certain foods in the context of a reaction time game. Chapter One presents an overview of the food Go/No-Go training literature.
Aims
In a series of experimental and feasibility studies, we aimed to answer the following questions: (i) can food Go/No-Go training lead to healthier food choices among children aged 4-11 years, (ii) how do variations in food Go/No-Go training tasks (e.g. different response signals, different delivery methods) impact the effectiveness of training on children’s food choices in relatively controlled settings, and (iii) how acceptable and feasible are different delivery methods of food Go/No-Go training for implementing in real-world environments?
Methods
Chapter Two presents four early experimental studies in a school setting, comparing the effects of food Go/No-Go training against a control task on children’s food choices in a hypothetical choice task. Chapter Three presents an experimental study (also in a school setting) exploring whether using evaluative response signals (happy and sad faces) enhances training effects on children’s food choices compared to neutral signals (green and red symbols). Chapter Four presents two feasibility studies exploring the delivery of computer-based Go/No-Go training to families via the internet. Chapter Five presents an experimental study in a school setting, comparing computer-based training and touchscreen-compatible app-based training against a control task. Chapter Six explores the feasibility of delivering app-based Go/No-Go training to families in a mixed-methods feasibility study taking a randomised controlled design. Finally, Chapter Seven presents a qualitative study, using a thematic analysis method to explore the experiences of parents in the UK who were engaged in family healthy eating efforts during the coronavirus pandemic. Chapter Eight summarises the research presented here, presents the results of mini meta-analyses of the studies included in this thesis, and suggests avenues for future research.
Results
In Chapter Two, children selected a significantly higher number of healthy foods after playing food Go/No-Go training compared to two different control tasks. In Chapter Three, no effect of food Go/No-Go training was observed (regardless of whether response signals were evaluative or neutral) which may have been due to large group sizes during testing (e.g. higher distraction and social influence during food choice). Attrition was high in the feasibility studies of Chapter Four, and feedback from parents suggested that the training would benefit from gamification and adaptation for touch-screens. In Chapter Five, computer-based (but not touch-screen app-based food Go/No-Go training) led to children choosing significantly higher numbers of healthy foods versus control - low statistical power may have masked an effect of app-based training. The feasibility study in Chapter Six met the majority of continuation criteria for feasibility and acceptability of the intervention and methods, however some families engaged very little with the food Go/No-Go training, and parent feedback indicated a number of ways the training could be optimised to enhance engagement. Chapter Seven revealed a number of challenges faced by parents during the UK lockdown in March 2020 (e.g. increased influence of children’s food requests on feeding decisions), reiterating why accessible interventions directly targeting children’s food preferences are needed in the wider toolkit of family-targeted healthy eating interventions. The mini meta-analyses in Chapter Eight suggested that both computer-based and app-based food Go/No-Go training significantly impact children’s food choices, but that the effect size for computer-based training is twice as large as that for app-based training, in line with research with this specific app with adult samples.

Conclusions
Overall, these studies indicate that food Go/No-Go training is a feasible, acceptable and effective tool that could be used to encourage healthier food choices among children. Further research should be undertaken to understand why the app-based training used in these studies yielded a smaller effect size than computer-based training, and whether an optimised, app-based intervention can be developed that both engages children and encourages them towards healthier food choices.

Current treatments for binge eating disorder (BED) and bulimia nervosa (BN) only show moderate efficacy, warranting the need for novel interventions. Impairments in food-related inhibitory control contribute to BED/BN and could be targeted by food-specific inhibitory control training (ICT). The aim of this study was to establish the feasibility and acceptability of augmenting treatment for individuals with BN/BED with an ICT app (FoodT), which targets motor inhibition to food stimuli using a go/no-go paradigm. Eighty patients with BED/BN receiving psychological and/or pharmacological treatment were randomly allocated to a treatment-as-usual group (TAU; n = 40) or TAU augmented with the 5-min FoodT app daily (n = 40) for 4 weeks. This mixed-methods study assessed feasibility outcomes, effect sizes of clinical change, and acceptability using self-report measures. Pre-registered cut-offs for recruitment, retention, and adherence were met, with 100% of the targeted sample size (n = 80) recruited within 12 months, 85% of participants retained at 4 weeks, and 80% of the FoodT + TAU group completing ≤8 sessions. The reduction in binge eating did not differ between groups. However, moderate reductions in secondary outcomes (eating disorder psychopathology: SES = -0.57, 95% CI [-1.12, -0.03]; valuation of high energy-dense foods: SES = -0.61, 95% CI [-0.87, -0.05]) were found in the FoodT group compared to TAU. Furthermore, small greater reductions in food addiction (SES = -0.46, 95% CI [-1.14, 0.22]) and lack of premeditation (SES = -0.42, 95% CI [-0.77, -0.07]) were found in the FoodT group when compared to TAU. The focus groups revealed acceptability of FoodT. Participants discussed personal barriers (e.g. distractions) and suggested changes to the app (e.g. adding a meditation exercise). Augmenting treatment for BED/BN with a food-specific ICT app is feasible, acceptable, and may reduce clinical symptomatology with high reach and wide dissemination.

Feelings of disgust toward meat have been researched for at least 30 years, but so far the causal relationship that may link meat disgust and meat consumption has remained elusive. Two possible pathways have been proposed in previous literature: the more common pathway seems to be that meat disgust is developed after a transition to vegetarianism, potentially via the process of moralization and recruitment of (moral) disgust. Other accounts suggest the existence of a second pathway in which disgust initiates the avoidance of meat and this can be explained by existing theories of disgust functioning as a pathogen avoidance mechanism and meat serving as a pathogen cue. However, the evidence base for either relationship remains thin and to our knowledge no research has examined whether temporary meat abstention can lead to increases in meat disgust, as the first pathway suggests. We measured meat disgust and meat intake in n = 40 meat eaters before and after attempting a meat-free diet for 1 month (while taking part in the annual vegan campaign Veganuary). Although most participants lapsed to eating meat during this period, we found that reductions in meat intake during the month were predictive of increases in meat disgust afterwards. This supports the view that meat disgust is expressed as a result of meat avoidance in meat eaters. Implications for theoretical understanding of the relationship between meat disgust and meat avoidance, as well as the development of disgust based interventions are discussed.

Objective: Inhibitory control training (ICT) has shown promise for improving health behaviours, however, less is known about its mediators of effectiveness. The current paper reports whether ICT reduces smoking-related outcomes such as craving and nicotine dependence, increases motivation to quit and whether reductions in smoking or craving are mediated by response inhibition or a devaluation of smoking stimuli. Method: Adult smokers (minimum 10 cigarettes per day; N = 107, M age. = 46.15 years, 57 female) were randomly allocated to receive 14 days of smoking-specific ICT (named INST; a go/no-go task where participants were trained to not respond to smoking stimuli) or active control training (participants inhibited responding toward neutral stimuli). Participants were followed up to 3-months post-intervention. This trial was preregistered (Australian and New Zealand Clinical Trials Registry ID: ACTRN12617000252314; URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=370204). Results: There were no significant differences between ICT and active control training groups. Specifically, participants in both groups showed significant reductions in craving, nicotine dependence, motivation and a devaluation (reduced evaluation) of smoking-stimuli up to 3-months follow-up compared to baseline. Inhibition and devaluation of smoking stimuli did not act as mediators. Devaluation of smoking stimuli was an independent predictor of smoking and craving at follow-up. Conclusion: Inhibitory control training (ICT) was no more effective at reducing smoking-related outcomes compared to the active control group, however, significant improvements in craving, dependence indicators and evaluation of smoking stimuli were observed across both groups. A return to basic experimental research may be required to understand the most effective ICT approach to support smoking cessation.

Food Go/No-Go training aims to alter implicit food biases by creating associations between perceiving unhealthy foods and withholding a dominant response. Asking participants to repeatedly inhibit an impulse to approach unhealthy foods can decrease unhealthy food intake in laboratory settings. Less is known about how people engage with app-based Go/No-Go training in real-world settings and how this might relate to dietary outcomes. This pragmatic observational study investigated associations between the number of completed app-based food Go/No-Go training trials and changes in food intake (Food Frequency Questionnaire; FFQ) for different healthy and unhealthy food categories from baseline to one-month follow-up. In total, 1234 participants (m(BMI) = 29 kg/m2, m(age) = 43years, 69% female) downloaded the FoodT app and completed food-Go/No-Go training at their own discretion (mean number of completed sessions = 10.7, sd = 10.3, range: 1-122). In pre-registered analyses, random-intercept linear models predicting intake of different foods, and controlled for baseline consumption, BMI, age, sex, smoking, metabolic syndrome, and dieting status, revealed small, significant associations between the number of completed training trials and reductions in unhealthy food intake (b = -0.0005, CI95= [-0.0007;-0.0003]) and increases in healthy food intake (b = 0.0003, CI95 = [0.0000; 0.0006]). These relationships varied by food category, and exploratory analyses suggest that more temporally spaced training was associated with greater changes in dietary intake. Taken together, these results imply a positive association between the amount of training completed and beneficial changes in food intake. However, the results of this pragmatic study should be interpreted cautiously, as self-selection biases, motivation and other engagement-related factors that could underlie these associations were not accounted for. Experimental research is needed to rule out these possible confounds and establish causal dose-response relationships between patterns of engagement with food Go/No-Go training and changes in dietary intake.

Binge eating disorder and bulimia nervosa are eating disorders that are characterized by recurrent binge eating episodes. The highly contextualized nature of binge eating makes naturalistic research a particularly suitable means of understanding the context within which binge eating occurs. The present study aimed to characterise binge eating days with regards to the frequency and probability of negative affect, food craving, meal skipping, and dietary restriction. In addition, it aimed to examine whether a combined intervention that targets the experience of 'loss of control' over eating can decrease these potential maintenance factors that often precede binge eating episodes. Seventy-eight participants with bulimia nervosa (N = 40) or binge eating disorder (n = 38), who were randomly allocated to a food-specific or general intervention combining inhibitory control training and implementation intentions, completed mood and food diaries over four weeks. Results suggest that negative affect and food craving were elevated on binge eating days, but that dietary restraint and meal skipping did not characterise binge eating days. Moreover, meal skipping, binge eating, restriction, and compensation decreased throughout the intervention period, while negative affect and food craving did not. This suggests that some interventions may successfully reduce binge eating frequency without necessarily decreasing negative affect or food craving, thus pointing to the different routes to targeting binge eating and providing implications for future interventions.

Inhibitory control training effects on behaviour (e.g. ‘healthier’ food choices) can be driven by changes in affective evaluations of trained stimuli, and theoretical models indicate that changes in action tendencies may be a complementary mechanism. In this preregistered study, we investigated the effects of food-specific go/no-go training on action tendencies, liking and impulsive choices in healthy participants. In the training task, energy-dense foods were assigned to one of three conditions: 100% inhibition (no-go), 0% inhibition (go) or 50% inhibition (control). Automatic action tendencies and liking were measured pre- and post-training for each condition. We found that training did not lead to changes in approach bias towards trained foods (go and no-go relative to control), but we warrant caution in interpreting this finding as there are important limitations to consider for the employed approach–avoidance task. There was only anecdotal evidence for an effect on food liking, but there was evidence for contingency learning during training, and participants were on average less likely to choose a no-go food compared to a control food after training. We discuss these findings from both a methodological and theoretical standpoint and propose that the mechanisms of action behind training effects be investigated further.

Humans generally fear those different to them (i.e. an out-group) in the same way they fear natural predators. But fear pushes us to derogate others, whether they constitute a threat or not. Research has examined how fear associated with specific intergroup relations interferes with how individuals relate to in-group and out-group members. However, we know relatively little about how intergroup relations might be affected by incidental emotions. We tested how incidental fear affects empathy toward in-group and out-group members. We found that exposing participants to fearful imagery was sufficient to reduce empathy, but only in response to out-group suffering. We discuss how these findings provide insight into how fear is often leveraged to encourage social tribalism. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

The reduction of portion sizes supports weight-loss. This study looks at whether children have a conceptual understanding of portion size, by studying their ability to manually serve a portion size that corresponds to what they eat. In a clinical setting, discussion around portion size is subjective thus a computerised portion size tool is also trialled, with the portion sizes chosen on the screen being compared to amounts served manually. Children (n = 76) age 5–6, 7–8 and 10–11 were asked to rate their hunger (VAS scale), liking (VAS scale) and ‘ideal portion size for lunch’ of eight interactive meal images using a computerised portion size tool. Children then manually self-served and consumed a portion of pasta. Plates were weighed to allow for the calculation of calories served and eaten. A positive correlation was found between manually served food portions and the amount eaten (r = 0.53, 95%CI [0.34, 0.82, P <. 001), indicating that many children were able to anticipate their likely food intake prior to meal onset. A regression model demonstrates that age contributes to 9.4% of the variance in portion size accuracy (t(68) = −2.3, p =. 02). There was no relationship between portion size and either hunger or liking. The portion sizes chosen on the computer at lunchtime correlated to the amount manually served overall (r =. 34, 95%CI [0.07, 0.55], p <. 01), but not in 5-6-year-old children. Manual portion-size selection can be observed in five-year olds and from age seven, children's ‘virtual’ responses correlate with their manual portion selections. The application of the computerised portion-size tool requires further development but offers considerable potential.

There is a widely acknowledged need to improve the reliability and efficiency of scientific research to increase the credibility of the published scientific literature and accelerate discovery. Widespread improvement requires a cultural shift in both thinking and practice, and better education will be instrumental to achieve this. Here we argue that education in reproducible science should start at the grassroots. We present our model of consortium-based student projects to train undergraduates in reproducible team science. We discuss how with careful design we have aligned collaboration with the current conventions for individual student assessment. We reflect on our experiences of several years running the GW4 Undergraduate Psychology Consortium offering insights we hope will be of practical use to others wishing to adopt a similar approach. We consider the pedagogical benefits of our approach in equipping students with 21st-century skills. Finally, we reflect on the need to shift incentives to reward to team science in global research and how this applies to the reward structures of student assessment.

OBJECTIVE: the high rates of illness and mortality associated with cigarette smoking necessitate the development of novel reduction and cessation treatments. Inhibitory control training (ICT) has recently emerged as a potentially efficacious intervention to reduce the consumption of alcohol and unhealthy food. This randomized controlled trial was the first to investigate the effect of Internet-delivered ICT on cigarette consumption in a community sample of heavy smokers. METHOD: for the present study, 107 adult smokers (mean age = 46.15 years; 57 female) who smoked a minimum of 10 cigarettes per day and met criteria for a moderate or severe tobacco use disorder were recruited. Participants were randomly allocated to receive go/no-go training in which either smoking stimuli (intervention) or nonsmoking stimuli (control) were paired with no-go signals and were instructed to complete 1 training session per day over a 2-week period. This trial was preregistered with the Australian and New Zealand Clinical Trials Registry (Trial ID: ACTRN12617000252314). RESULTS: We found no significant differences between conditions on percentage of days abstinent or daily cigarette consumption, although there was a significant decrease in daily cigarette consumption across both conditions. Further, we found no significant moderating effects of impulsivity on the relationship between cigarette consumption and the 2 tasks. CONCLUSIONS: Although participants in both conditions reduced their daily cigarette consumption, the intervention task was no more successful than the control task was in achieving cigarette abstinence or reduction. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Policymakers are focused on reducing the public health burden of obesity. The UK average percentage of adults classified as obese is 26%, which is double that of the global average. Over a third of UK adults report using at least one weight management aid. Yet, many people still struggle to change their diet-related behaviour, despite having the awareness, intention and capability to do so. This ‘intention–behaviour gap’ may be because most existing dietary-choice interventions focus on individual decision-making, ignoring the effects of environmental cues on human behaviour. Behaviour change interventions that ‘nudge’ people into making healthier choices by modifying the food environment have been shown to be effective. However, this type of intervention is typically challenging for policymakers to implement for economic, ethical and public accessibility reasons. To overcome these concerns, policymakers should consider ‘boosting’ interventions. Boosting involves enhancing competences that help people make decisions consistent with their goals. Here, we outline cognitive training as a boosting intervention to tackle obesity. We synthesize the evidence for one type of cognitive training (go/no-go training) that may be effective at modifying food-related decisions and reducing body weight. We offer evidence-based recommendations for an obesity-focused Public Health Wales behaviour change programme.

Meat consumption is damaging to the environment, health and animal welfare. Despite a growing interest in reducing meat intake, many people eat too much. This is partly due to the pleasure associated with eating meat. Research has used go/no-go response inhibition training (RIT) to reduce the intake and reward value (liking) of snack foods. However, RIT has not yet been applied to meat. We investigated whether an internet-delivered RIT with meat pictures would reduce meat intake and liking relative to a non-food control RIT condition. Participants (N = 81) were meat eaters with a desire to reduce their intake. They completed four 10-min training sessions in one week. Active participants inhibited responses to meat, and responded to fruits and vegetables. Meat intake was measured using food frequency questionnaires at pre- and one month post-training, and a daily meat diary for one week during training. Liking of meat and other foods was measured at pre- and one month post-training. There was a reduction in meat intake over one month in both groups, with active participants showing a significantly larger decrease than controls. Conditions did not differ in meat intake during the training week. Both groups showed a devaluation of meat, with active participants showing a significantly larger devaluation of food overall, suggesting some generalisation of devaluation effects. The reduced frequency of meat intake was associated with greater devaluation of meat in active but not control participants. These findings suggest that meat RIT helps to reduce meat intake and food liking. Future research should conduct larger randomised controlled trials with longer-term outcomes.

Despite being used interchangeably, different measures of restrained eating have been associated with different dietary behaviours. These differences have impeded replicability across the restraint literature and have made it difficult for researchers to interpret results and use the most appropriate measure for their research. Across a total sample of 1731 participants, this study compared the Restraint Scale (RS), and its subscales, to the Dutch Eating Behaviour Questionnaire (DEBQ) across several traits related to overeating. The aim was to explore potential differences between these two questionnaires so that we could help to identify the most suitable measure as a prescreening tool for eating-related interventions. Results revealed that although the two measures are highly correlated with one another (rs = 0.73-0.79), the RS was more strongly associated with external (rs = -0.07 to 0.11 versus -0.18 to -0.01) and disinhibited eating (rs = 0.46 versus 0.31), food craving (rs = 0.12-0.27 versus 0.02-0.13 and 0.22 versus -0.06) and body mass index (rs = 0.25-0.34 versus -0.13 to 0.15). The results suggest that, compared to the DEBQ, the RS is a more appropriate measure for identifying individuals who struggle the most to control their food intake.

Background: ImpulsePal is a theory-driven (dual-process), evidence-informed, and person-centered smartphone app intervention designed to help people manage impulsive processes that prompt unhealthy eating to facilitate dietary change and weight loss.

Objective: the aims of this study were to (1) assess the feasibility of trial procedures for evaluation of the ImpulsePal intervention, (2) estimate standard deviations of outcomes, and (3) assess usability of, and satisfaction with, ImpulsePal.

Methods: We conducted an individually randomized parallel two-arm nonblinded feasibility trial. The eligibility criteria included being aged ≥16 years, having a body mass index of ≥25 kg/m2, and having access to an Android-based device. Weight was measured (as the proposed primary outcome for a full-scale trial) at baseline, 1 month, and 3 months of follow-up. Participants were randomized in a 2:1 allocation ratio to the ImpulsePal intervention or a waiting list control group. A nested action-research study allowed for data-driven refinement of the intervention across 2 cycles of feedback.

Results: We screened 179 participants for eligibility, and 58 were randomized to the intervention group and 30 to the control group. Data were available for 74 (84%, 74/88) participants at 1 month and 67 (76%, 67/88) participants at 3 months. The intervention group (n=43) lost 1.03 kg (95% CI 0.33 to 1.74) more than controls (n=26) at 1 month and 1.01 kg (95% CI −0.45 to 2.47) more than controls (n=43 and n=24, respectively) at 3 months. Feedback suggested changes to intervention design were required to (1) improve receipt and understanding of instructions and (2) facilitate further engagement with the app and its strategies.

Conclusions: the evaluation methods and delivery of the ImpulsePal app intervention are feasible, and the trial procedures, measures, and intervention are acceptable and satisfactory to the participants.

Trial Registration: International Standard Randomized Controlled Trial Number (ISRCTN): 14886370; http://www.isrctn.com/ISRCTN14886370 (Archived by WebCite at http://www.webcitation.org/76WcEpZ51)

With the obesity epidemic being largely attributed to overeating, much research has been aimed at understanding the psychological causes of overeating and using this knowledge to develop targeted interventions. Here, we review this literature under a model of food addiction and present evidence according to the fifth edition of the Diagnostic and Statistical Manual (DSM-5) criteria for substance use disorders. We review several innovative treatments related to a food addiction model ranging from cognitive intervention tasks to neuromodulation techniques. We conclude that there is evidence to suggest that, for some individuals, food can induce addictive-type behaviours similar to those seen with other addictive substances. However, with several DSM-5 criteria having limited application to overeating, the term 'food addiction' is likely to apply only in a minority of cases. Nevertheless, research investigating the underlying psychological causes of overeating within the context of food addiction has led to some novel and potentially effective interventions. Understanding the similarities and differences between the addictive characteristics of food and illicit substances should prove fruitful in further developing these interventions.

Meat consumption is damaging to the environment, health and animal welfare. Despite a growing interest in reducing meat intake, many people eat too much. This is partly due to the pleasure associated with eating meat. Research has used go/no-go response inhibition training (RIT) to reduce the intake and reward value (liking) of snack foods. However, RIT has not yet been applied to meat. We investigated whether an internet-delivered RIT with meat pictures would reduce meat intake and liking relative to a non-food control RIT condition. Participants (N = 81) were meat eaters with a desire to reduce their intake. They completed four 10-min training sessions in one week. Active participants inhibited responses to meat, and responded to fruits and vegetables. Meat intake was measured using food frequency questionnaires at pre- and one month post-training, and a daily meat diary for one week during training. Liking of meat and other foods was measured at pre- and one month post-training. There was a reduction in meat intake over one month in both groups, with active participants showing a significantly larger decrease than controls. Conditions did not differ in meat intake during the training week. Both groups showed a devaluation of meat, with active participants showing a significantly larger devaluation of food overall, suggesting some generalisation of devaluation effects. The reduced frequency of meat intake was associated with greater devaluation of meat in active but not control participants. These findings suggest that meat RIT helps to reduce meat intake and food liking. Future research should conduct larger randomised controlled trials with longer-term outcomes.

Access to reliable and timely information ensures that decision-makers can operate effectively. The motivations and challenges of parliamentarians and policy-makers in accessing evidence have been well documented in the policy literature. However, there has been little focus on research-providers. Understanding both the demand- and the supply-side of research engagement is imperative to enhancing impactful interactions. Here, we examine the broader experiences, motivations and challenges of UK-based research professionals engaging with research-users relevant to policy-making and scrutiny in the UK using a nationwide online questionnaire. The context of the survey partly involved contributing to the UK Evidence Information Service (EIS), a proposed rapid match-making service to facilitate interaction between parliamentary arenas that use evidence and research-providers. Our findings reveal, at least for this sub-sample who responded, that there are gender-related differences in policy-related experience, motivations, incentives and challenges for research professionals to contribute to evidence-informed decision-making through initiatives such as the EIS. Male and female participants were equally likely to have policy experience; however, males reported both significantly broader engagement with the research-users included in the survey and significantly higher levels of engagement with each research-user. Reported incentives for engagement included understanding what the evidence will be used for, guidance on style and content of contribution, and acknowledgement of contributions by the policymaker or elected official. Female participants were significantly more likely to select the guidance-related options. The main reported barrier was workload. We discuss how academia-policy engagement initiatives can best address these issues in ways that enhance the integration of research evidence with policy and practice across the UK.

© 2018 the Author(s). Background: Smoking is one of the leading preventable causes of illness and premature death worldwide. Despite a variety of effective treatments, relapse rates remain high, and novel, innovative interventions are needed in order to reduce the global prevalence of smoking. Research has indicated that deficits in the ability to inhibit a response (referred to as response inhibition) is a predictor of relapse and subsequently, targeting this potentially modifiable risk factor may lead to improvements in smoking outcomes. Indeed, in recent years, stimulus-specific response inhibition training has emerged as a potentially efficacious intervention to reduce unwanted/unhealthy behaviours such as alcohol and unhealthy food consumption. As such, the present trial is the first to evaluate the real-world efficacy of response inhibition smoking training (INST) in a sample of adult heavy smokers. Methods/design: This randomised controlled trial will recruit nicotine dependent smokers aged between 18 and 60 using social media and advertisements in Victoria, Australia. The sample target was 150 to account for drop out and non-adherence. Once informed consent has been obtained, participants complete a range of baseline measures during a face to face interview. Participants are randomly allocated to one of two online training conditions: an intervention training group (INST), which requires participants to exercise response inhibition towards smoking-related stimuli; or an active control group, which requires participants to exercise response inhibition towards household items and does not include any smoking-related stimuli. They complete the first training session during the interview to ensure the training protocol is clear. Both groups are instructed to complete a further 13 training sessions (1 per day) at home on their computer and follow-up phone calls will be conducted at three time points: post-intervention, one-month and three months. The primary outcomes are: a) rates of smoking cessation and; b) reduction in the quantity of average daily smoking at post-intervention, one and three months follow-up. Discussion: There is a pressing need to develop novel and innovative smoking interventions. If proven to be effective, INST could make a highly cost-effective contribution to improvements in smoking intervention outcomes. Trial registration: the trial was prospectively registered with the Australian New Zealand Clinical Trials Registry 17th February 2017. Trial ID: ACTRN12617000252314.

The aim of this review is to critically evaluate the effectiveness and candidate mechanisms of action of psychological interventions which aim to either (a) improve the capacity for self-regulatory, reflective processes or (b) reduce the impact of automatic appetitive processes, in an attempt to influence food intake and associated weight-gain. Our aim was to examine three important issues regarding each type of intervention: i) whether the intervention influenced behaviour in the laboratory, ii) whether the intervention influenced behaviour and/or body mass index in the real world, and iii) whether the proposed mechanism of action was supported by evidence. We systematically searched three commonly used databases and identified 32 articles which were relevant to at least one of these issues. The majority of studies attempted to manipulate food intake in the laboratory using associative learning paradigms, in normal-weight female participants. Most of the laboratory studies demonstrated the predicted effects of interventions on behaviour in the laboratory, but studies that attempted to translate these interventions outside of the laboratory yielded more mixed findings. The hypothesised mechanisms of action received inconsistent support across studies. We identified several limitations which may complicate interpretation of findings in this area, including heterogeneity of study methods, small sample sizes, and absence of adequate control groups. We provide recommendations for future studies that aim to develop and evaluate these promising interventions for the reduction of overweight and obesity.

Despite decades of research, the pathophysiology of bipolar disorder (BD) is still not well understood. Structural brain differences have been associated with BD, but results from neuroimaging studies have been inconsistent. To address this, we performed the largest study to date of cortical gray matter thickness and surface area measures from brain magnetic resonance imaging scans of 6503 individuals including 1837 unrelated adults with BD and 2582 unrelated healthy controls for group differences while also examining the effects of commonly prescribed medications, age of illness onset, history of psychosis, mood state, age and sex differences on cortical regions. In BD, cortical gray matter was thinner in frontal, temporal and parietal regions of both brain hemispheres. BD had the strongest effects on left pars opercularis (Cohen's d=-0.293; P=1.71 × 10-21), left fusiform gyrus (d=-0.288; P=8.25 × 10-21) and left rostral middle frontal cortex (d=-0.276; P=2.99 × 10-19). Longer duration of illness (after accounting for age at the time of scanning) was associated with reduced cortical thickness in frontal, medial parietal and occipital regions. We found that several commonly prescribed medications, including lithium, antiepileptic and antipsychotic treatment showed significant associations with cortical thickness and surface area, even after accounting for patients who received multiple medications. We found evidence of reduced cortical surface area associated with a history of psychosis but no associations with mood state at the time of scanning. Our analysis revealed previously undetected associations and provides an extensive analysis of potential confounding variables in neuroimaging studies of BD.

Children consume too much sugar and not enough fruit and vegetables, increasing their risk of adverse health outcomes. Inhibitory control training (ICT) reduces children’s and adults’ intake of energy-dense foods in both laboratory and real-life settings. However, no studies have yet examined whether ICT can increase healthy food choice when energy-dense options are also available. We investigated whether a food-specific Go/No-Go task could influence the food choices of children aged 4-11, as measured by a hypothetical food choice task using healthy and unhealthy food images printed on cards. Participants played either an active game (healthy foods = 100% go, unhealthy foods = 100% no-go; Studies 1 & 2), a food control game (both healthy and unhealthy foods = 50% go, 50% no-go; Studies 1 & 2) or a non-food control game (sports equipment = 100% go, technology = 100% no-go; Study 2 only) followed by the choice task. In Study 2, food card choices were also measured before training to examine change in choices. A post-training real food choice task was added to check that choices made in the card-based task were representative of choices made when faced with real healthy and unhealthy foods. Overall, the active group chose the greatest number of healthy food cards. Study 2 confirmed that this was due to increases in healthy food card choice in this group only. Active group participants chose a greater number of healthy foods in the real food choice task compared to children in the non-food control group only. The results are discussed with reference to methodological issues and the development of future healthy eating interventions.

Dataset in SPSS and CSV format for Study 1 and Study 2 described in the manuscript with the above title

FMRI-based neurofeedback transforms functional brain activation in real-time into sensory stimuli that participants can use to self-regulate brain responses, which can aid the modification of mental states and behavior. Emerging evidence supports the clinical utility of neurofeedback-guided up-regulation of hypoactive networks. In contrast, down-regulation of hyperactive neural circuits appears more difficult to achieve. There are conditions though, in which down-regulation would be clinically useful, including dysfunctional motivational states elicited by salient reward cues, such as food or drug craving. In this proof-of-concept study, 10 healthy females (mean age = 21.40 years, mean BMI = 23.53) who had fasted for 4 h underwent a novel 'motivational neurofeedback' training in which they learned to down-regulate brain activation during exposure to appetitive food pictures. FMRI feedback was given from individually determined target areas and through decreases/increases in food picture size, thus providing salient motivational consequences in terms of cue approach/avoidance. Our preliminary findings suggest that motivational neurofeedback is associated with functionally specific activation decreases in diverse cortical/subcortical regions, including key motivational areas. There was also preliminary evidence for a reduction of hunger after neurofeedback and an association between down-regulation success and the degree of hunger reduction. Decreasing neural cue responses by motivational neurofeedback may provide a useful extension of existing behavioral methods that aim to modulate cue reactivity. Our pilot findings indicate that reduction of neural cue reactivity is not achieved by top-down regulation but arises in a bottom-up manner, possibly through implicit operant shaping of target area activity.

Elevated brain reward and attention region response, and weaker inhibitory region response to high-calorie food images have been found to predict future weight gain. These findings suggest that an intervention that reduces reward and attention region response and increases inhibitory control region response to such foods might reduce overeating. We conducted a randomized pilot experiment that tested the hypothesis that a multi-faceted food response and attention training with personalized high- and low-calorie food images would produce changes in behavioral and neural responses to food images and body fat compared to a control training with non-food images among community-recruited overweight/obese adults. Compared to changes observed in controls, completing the intervention was associated with significant reductions in reward and attention region response to high-calorie food images (Mean Cohen's d = 1.54), behavioral evidence of learning, reductions in palatability ratings and monetary valuation of high-calorie foods (p = 0.009, d's = 0.92), and greater body fat loss over a 4-week period (p = 0.009, d = 0.90), though body fat effects were not significant by 6-month follow-up. Results suggest that this multifaceted response and attention training intervention was associated with reduced reward and attention region responsivity to food cues, and a reduction in body fat. Because this implicit training treatment is both easy and inexpensive to deliver, and does not require top-down executive control that is necessary for negative energy balance obesity treatment, it may prove useful in treating obesity if future studies can determine how to create more enduring effects.

Training individuals to inhibit their responses towards unhealthy foods has been shown to reduce food intake relative to a control group. Here we aimed to further explore these effects by investigating the role of stimulus devaluation, training protocol, and choice of control group. Restrained eaters received either inhibition or control training using a modified version of either the stop-signal or go/no-go task. Following training we measured implicit attitudes towards food (Study 1) and food consumption (Studies 1 and 2). In Study 1 we used a modified stop-signal training task with increased demands on top-down control (using a tracking procedure and feedback to maintain competition between the stop and go processes). With this task, we found no evidence for an effect of training on implicit attitudes or food consumption, with Bayesian inferential analyses revealing substantial evidence for the null hypothesis. In Study 2 we removed the feedback in the stop-signal training to increase the rate of successful inhibition and revealed a significant effect of both stop-signal and go/no-go training on food intake (compared to double-response and go training, respectively) with a greater difference in consumption in the go/no-go task, compared with the stop-signal task. However, results from an additional passive control group suggest that training effects could be partly caused by increased consumption in the go control group whereas evidence for reduced consumption in the inhibition groups was inconclusive. Our findings therefore support evidence that inhibition training tasks with higher rates of inhibition accuracy are more effective, but prompt caution for interpreting the efficacy of laboratory-based inhibition training as an intervention for behaviour change.

BackgroundCognitive tasks are typically viewed as effortful, frustrating, and repetitive, which often leads to participant disengagement. This, in turn, may negatively impact data quality and/or reduce intervention effects. However, gamification may provide a possible solution. If game design features can be incorporated into cognitive tasks without undermining their scientific value, then data quality, intervention effects, and participant engagement may be improved.ObjectivesThis systematic review aims to explore and evaluate the ways in which gamification has already been used for cognitive training and assessment purposes. We hope to answer 3 questions: (1) Why have researchers opted to use gamification? (2) What domains has gamification been applied in? (3) How successful has gamification been in cognitive research thus far?MethodsWe systematically searched several Web-based databases, searching the titles, abstracts, and keywords of database entries using the search strategy (gamif. OR game OR games) AND (cognit. OR engag. OR behavi. OR health. OR attention OR motiv*). Searches included papers published in English between January 2007 and October 2015.ResultsOur review identified 33 relevant studies, covering 31 gamified cognitive tasks used across a range of disorders and cognitive domains. We identified 7 reasons for researchers opting to gamify their cognitive training and testing. We found that working memory and general executive functions were common targets for both gamified assessment and training. Gamified tests were typically validated successfully, although mixed-domain measurement was a problem. Gamified training appears to be highly engaging and does boost participant motivation, but mixed effects of gamification on task performance were reported.ConclusionsHeterogeneous study designs and typically small sample sizes highlight the need for further research in both gamified training and testing. Nevertheless, careful application of gamification can provide a way to develop engaging and yet scientifically valid cognitive assessments, and it is likely worthwhile to continue to develop gamified cognitive tasks in the future.

Previously, studies have demonstrated cortical impairments in those who complete or attempt suicide. Subcortical nuclei have less often been implicated in the suicidal vulnerability. In the present study, we investigated, with a specific design in a large population, variations in the volume of subcortical structures in patients with mood disorders who have attempted suicide. We recruited 253 participants: 73 suicide attempters with a past history of both mood disorders and suicidal act, 89 patient controls with a past history of mood disorders but no history of suicidal act, and 91 healthy controls. We collected 1.5 T magnetic resonance imaging data from the caudate, pallidum, putamen, nucleus accumbens, hippocampus, amygdala, ventral diencephalon, and thalamus. Surface-based morphometry (Freesurfer) analysis was used to comprehensively evaluate gray matter volumes. In comparison to controls, suicide attempters showed no difference in subcortical volumes when controlled for intracranial volume. However, within attempters negative correlations between the left (r = -0.35, p = 0.002), and right (r = -0.41, p < 0.0005) nucleus accumbens volumes and the lethality of the last suicidal act were found. Our study found no differences in the volume of eight subcortical nuclei between suicide attempters and controls, suggesting a lack of association between these regions and suicidal behavior in general. However, individual variations in nucleus accumbens structure and functioning may modulate the lethality of suicidal acts during a suicidal crisis. The known role of nucleus accumbens in action selection toward goals determined by the prefrontal cortex, decision-making or mental pain processing are hypothesized to be potential explanations.

Considerable uncertainty exists about the defining brain changes associated with bipolar disorder (BD). Understanding and quantifying the sources of uncertainty can help generate novel clinical hypotheses about etiology and assist in the development of biomarkers for indexing disease progression and prognosis. Here we were interested in quantifying case-control differences in intracranial volume (ICV) and each of eight subcortical brain measures: nucleus accumbens, amygdala, caudate, hippocampus, globus pallidus, putamen, thalamus, lateral ventricles. In a large study of 1710 BD patients and 2594 healthy controls, we found consistent volumetric reductions in BD patients for mean hippocampus (Cohen's d=-0.232; P=3.50 × 10-7) and thalamus (d=-0.148; P=4.27 × 10-3) and enlarged lateral ventricles (d=-0.260; P=3.93 × 10-5) in patients. No significant effect of age at illness onset was detected. Stratifying patients based on clinical subtype (BD type I or type II) revealed that BDI patients had significantly larger lateral ventricles and smaller hippocampus and amygdala than controls. However, when comparing BDI and BDII patients directly, we did not detect any significant differences in brain volume. This likely represents similar etiology between BD subtype classifications. Exploratory analyses revealed significantly larger thalamic volumes in patients taking lithium compared with patients not taking lithium. We detected no significant differences between BDII patients and controls in the largest such comparison to date. Findings in this study should be interpreted with caution and with careful consideration of the limitations inherent to meta-analyzed neuroimaging comparisons.

Major depressive disorder (MDD) is associated with specific difficulties in attentional disengagement from negatively valenced material. Diffusion MRI studies have demonstrated altered white matter microstructure in the subgenual cingulum bundle (CB) in individuals with MDD, though the functional significance of these alterations has not been examined formally. This study explored whether individual differences in selective attention to negatively valenced stimuli are related to interindividual differences in subgenual CB microstructure. Forty-six individuals (21 with remitted MDD, 25 never depressed) completed an emotional Stroop task, using happy and angry distractor faces overlaid by pleasant or unpleasant target words and a control gender-based Stroop task. CBs were reconstructed in 38 individuals using diffusion-weighted imaging and tractography, and mean fractional anisotropy (FA) computed for the subgenual, retrosplenial, and parahippocampal subdivisions. No significant correlations were found between FA and performance in the control gender-based Stroop task in any CB region. However, the degree of interference produced by angry face distractors on time to identify pleasant words (emotional conflict) correlated selectively with FA in the subgenual CB (r = -0.53; P = 0.01). Higher FA was associated with reduced interference, irrespective of a diagnosis of MDD, suggesting that subgenual CB microstructure is functionally relevant for regulating attentional bias toward negative interpersonal stimuli.

The present review first summarizes results from prospective brain imaging studies focused on identifying neural vulnerability factors that predict excessive weight gain. Next, findings from cognitive psychology experiments evaluating various interventions involving food response inhibition training or food response facilitation training are reviewed that appear to target these neural vulnerability factors and that have produced encouraging weight loss effects. Findings from both of these reviewed research fields suggest that interventions that reduce reward and attention region responses to high calorie food cues and increase inhibitory region responses to high calorie food cues could prove useful in the treatment of obesity. Based on this review, a new conceptual model is presented to describe how different cognitive training procedures may contribute to modifying eating behavior and important directions for future research are offered. It is concluded that there is a need for evaluating the effectiveness of more intensive food response training interventions and testing whether adding such training to extant weight loss interventions increases their efficacy.

A predominant expectation that social relationships with others are safe (a secure attachment style), has been linked with reduced threat-related amygdala activation. Experimental priming of mental representations of attachment security can modulate neural responding, but the effects of attachment-security priming on threat-related amygdala activation remains untested. Using functional magnetic resonance imaging, the present study examined the effects of trait and primed attachment security on amygdala reactivity to threatening stimuli in an emotional faces and a linguistic dot-probe task in 42 healthy participants. Trait attachment anxiety and attachment avoidance were positively correlated with amygdala activation to threatening faces in the control group, but not in the attachment primed group. Furthermore, participants who received attachment-security priming showed attenuated amygdala activation in both the emotional faces and dot-probe tasks. The current findings demonstrate that variation in state and trait attachment security modulates amygdala reactivity to threat. These findings support the potential use of attachment security-boosting methods as interventions and suggest a neural mechanism for the protective effect of social bonds in anxiety disorders.

OBJECTIVES: Emotion regulation deficits are a core feature of bipolar disorder. However, their potential neurobiological underpinnings and existence beyond bipolar I disorder remain unexplored. Our main goal was to investigate whether both individuals with bipolar I and bipolar II disorder show deficits in emotion regulation during an attention control task, and to explore the neurophysiological underpinnings of this potential deficit. METHODS: Twenty healthy controls, 16 euthymic participants with bipolar I disorder, and 19 euthymic participants with bipolar II disorder completed psychometric and clinical assessments, a neuroimaging emotion regulation paradigm, and an anatomical diffusion-weighted scan. Groups were matched for age, gender, and verbal IQ. RESULTS: During the presence of emotional distracters, subjects with bipolar I disorder showed slowed reaction times to targets, and increased blood oxygenation level-dependent (BOLD) responses in the amygdala, accumbens, and dorsolateral prefrontal cortex, but not increased inverse functional connectivity between these prefrontal and subcortical areas, and altered white matter microstructure organization in the right uncinate fasciculus. Subjects with bipolar II disorder showed no altered reaction times, increased BOLD responses in the same brain areas, increased inverse functional connectivity between the prefrontal cortex and amygdala, and no abnormalities in white matter organization. CONCLUSIONS: Participants with bipolar I disorder showed abnormalities in functional and anatomical connectivity between prefrontal cortices and subcortical structures in emotion regulation circuitry. However, these deficits did not extend to subjects with bipolar II disorder, suggesting fundamental differences in the pathophysiology of bipolar disorder subtypes.

The vulnerability to suicidal behavior has been modeled in deficits in both valuation and cognitive control processes, mediated by ventral and dorsal prefrontal cortices. To uncover potential markers of suicidality based on this model, we measured several brain morphometric parameters using 1.5T magnetic resonance imaging in a large sample and in a specifically designed study. We then tested their classificatory properties. Three groups were compared: euthymic suicide attempters with a past history of mood disorders and suicidal behavior (N=67); patient controls with a past history of mood disorders but not suicidal behavior (N=82); healthy controls without any history of mental disorder (N=82). A hypothesis-driven region-of-interest approach was applied targeting the orbitofrontal cortex (OFC), ventrolateral (VLPFC), dorsal (DPFC) and medial (including anterior cingulate cortex; MPFC) prefrontal cortices. Both voxel-based (SPM8) and surface-based morphometry (Freesurfer) analyses were used to comprehensively evaluate cortical gray matter measure, volume, surface area and thickness. Reduced left VLPFC volume in attempters vs both patient groups was found (P=0.001, surviving multiple comparison correction, Cohen's d=0.65 95% (0.33-0.99) between attempters and healthy controls). In addition, reduced measures in OFC and DPFC, but not MPFC, were found with moderate effect sizes in suicide attempters vs healthy controls (Cohen's d between 0.34 and 0.52). Several of these measures were correlated with suicidal variables. When added to mood disorder history, left VLPFC volume increased within-sample specificity in identifying attempters in a significant but limited way. Our study, therefore, confirms structural prefrontal alterations in individuals with histories of suicide attempts. A future clinical application of these markers will, however, necessitate further research.

Following exposure to consistent stimulus-stop mappings, response inhibition can become automatized with practice. What is learned is less clear, even though this has important theoretical and practical implications. A recent analysis indicates that stimuli can become associated with a stop signal or with a stop goal. Furthermore, expectancy may play an important role. Previous studies that have used stop or no-go signals to manipulate stimulus-stop learning cannot distinguish between stimulus-signal and stimulus-goal associations, and expectancy has not been measured properly. In the present study, participants performed a task that combined features of the go/no-go task and the stop-signal task in which the stop-signal rule changed at the beginning of each block. The go and stop signals were superimposed over 40 task-irrelevant images. Our results show that participants can learn direct associations between images and the stop goal without mediation via the stop signal. Exposure to the image-stop associations influenced task performance during training, and expectancies measured following task completion or measured within the task. But, despite this, we found an effect of stimulus-stop learning on test performance only when the task increased the task-relevance of the images. This could indicate that the influence of stimulus-stop learning on go performance is strongly influenced by attention to both task-relevant and task-irrelevant stimulus features. More generally, our findings suggest a strong interplay between automatic and controlled processes. (PsycINFO Database Record

Overeating in our food-rich environment is a key contributor to obesity. Computerised response-inhibition training could improve self-control in individuals who overeat. Evidence suggests that training people to inhibit motor responses to specific food pictures can reduce the subsequent choice and consumption of those foods. Here we undertook three experiments using the stop-signal task to examine the effects of food and non-food related stop-training on immediate snack food consumption. The experiments examined whether training effects were stimulus-specific, whether they were influenced by the comparator (control) group, and whether they were moderated by individual differences in dietary restraint. Experiment 1 revealed lower intake of one food following stop- vs. double- (two key-presses) response training to food pictures. Experiment 2 offered two foods, one of which was not associated with stopping, to enable within- and between-subjects comparisons of intake. A second control condition required participants to ignore signals and respond with one key-press to all pictures. There was no overall effect of training on intake in Experiment 2, but there was a marginally significant moderation by dietary restraint: Restrained eaters ate significantly less signal-food following stop- relative to double-response training. Experiment 3 revealed that stop- vs. double-response training to non-food pictures had no effect on food intake. Taken together with previous findings, these results suggest some stimulus-specific effects of stop-training on food intake that may be moderated by individual differences in dietary restraint.

The majority of adults in the UK and US are overweight or obese due to multiple factors including excess energy intake. Training people to inhibit simple motor responses (key presses) to high-energy density food pictures reduces intake in laboratory studies. We examined whether online response inhibition training reduced real-world food consumption and weight in a community sample of adults who were predominantly overweight or obese (N = 83). Participants were allocated in a randomised, double-blind design to receive four 10-min sessions of either active or control go/no-go training in which either high-energy density snack foods (active) or non-food stimuli (control) were associated with no-go signals. Participants' weight, energy intake (calculated from 24-h food diaries), daily snacking frequency and subjective food evaluations were measured for one week pre- and post-intervention. Participants also provided self-reported weight and monthly snacking frequency at pre-intervention screening, and one month and six months after completing the study. Participants in the active relative to control condition showed significant weight loss, reductions in daily energy intake and a reduction in rated liking of high-energy density (no-go) foods from the pre-to post-intervention week. There were no changes in self-reported daily snacking frequency. At longer-term follow-up, the active group showed significant reductions in self-reported weight at six months, whilst both groups reported significantly less snacking at one- and six-months. Excellent rates of adherence (97%) and positive feedback about the training suggest that this intervention is acceptable and has the potential to improve public health by reducing energy intake and overweight.

In slot machine gambling, the "near-miss effect" (when a losing display physically resembles an actual win display) has been implicated in pathological gambling (PG). Functional magnetic resonance imaging (fMRI) with PG and non-PG participants shows that near-misses recruit reward-related circuitry, but little is known about the temporal dynamics and oscillatory changes underlying near-misses. The present multi-modal imaging study investigated the near-miss effect by combining the spatial resolution of blood oxygen-level dependent (BOLD)-fMRI with the spatial and temporal resolution of magnetoencephalography (MEG) during a slot machine task in PG and non-PG groups. Given previous findings on outcome (win and near-miss) processing, functional overlap was hypothesized between induced changes in temporal oscillations and BOLD response to wins and near-misses in PG. We first validated our task in a sample of varying gambling severity using BOLD-fMRI and then compared PG and non-PG participants using MEG to investigate changes in induced oscillatory power associated with win and near-miss, relative to loss, outcomes. Across both modalities, near-misses recruited similar brain regions to wins, including right inferior frontal gyrus and insula. Using MEG, increased theta-band (4-7Hz) oscillations to near-misses were observed in the insula and right orbitofrontal cortex (OFC). Furthermore, this theta-band activity was positively associated with gambling severity. These findings demonstrate that the near-miss effect in insula and OFC is associated with induced theta oscillations. The significance of these findings for theories of PG and the development of potential biomarkers and therapeutic targets is discussed.

BACKGROUND: Although cognitive behavioral therapy (CBT) is an effective treatment for obsessive-compulsive disorder (OCD), few reliable predictors of treatment outcome have been identified. The present study examined the neural correlates of symptom improvement with CBT among OCD patients with predominantly contamination obsessions and washing compulsions, the most common OCD symptom dimension. METHOD: Participants consisted of 12 OCD patients who underwent symptom provocation with contamination-related images during functional magnetic resonance imaging (fMRI) scanning prior to 12 weeks of CBT. RESULTS: Patterns of brain activity during symptom provocation were correlated with a decrease on the Yale-Brown Obsessive Compulsive Scale (YBOCS) after treatment, even when controlling for baseline scores on the YBOCS and the Beck Depression Inventory (BDI) and improvement on the BDI during treatment. Specifically, activation in brain regions involved in emotional processing, such as the anterior temporal pole and amygdala, was most strongly associated with better treatment response. By contrast, activity in areas involved in emotion regulation, such as the dorsolateral prefrontal cortex, correlated negatively with treatment response mainly in the later stages within each block of exposure during symptom provocation. CONCLUSIONS: Successful recruitment of limbic regions during exposure to threat cues in patients with contamination-based OCD may facilitate a better response to CBT, whereas excessive activation of dorsolateral prefrontal regions involved in cognitive control may hinder response to treatment. The theoretical implications of the findings and their potential relevance to personalized care approaches are discussed.

The Enhancing NeuroImaging Genetics through Meta-Analysis (ENIGMA) Consortium is a collaborative network of researchers working together on a range of large-scale studies that integrate data from 70 institutions worldwide. Organized into Working Groups that tackle questions in neuroscience, genetics, and medicine, ENIGMA studies have analyzed neuroimaging data from over 12,826 subjects. In addition, data from 12,171 individuals were provided by the CHARGE consortium for replication of findings, in a total of 24,997 subjects. By meta-analyzing results from many sites, ENIGMA has detected factors that affect the brain that no individual site could detect on its own, and that require larger numbers of subjects than any individual neuroimaging study has currently collected. ENIGMA's first project was a genome-wide association study identifying common variants in the genome associated with hippocampal volume or intracranial volume. Continuing work is exploring genetic associations with subcortical volumes (ENIGMA2) and white matter microstructure (ENIGMA-DTI). Working groups also focus on understanding how schizophrenia, bipolar illness, major depression and attention deficit/hyperactivity disorder (ADHD) affect the brain. We review the current progress of the ENIGMA Consortium, along with challenges and unexpected discoveries made on the way.

BACKGROUND: a variety of cognitive and emotional processes influence the decision-making deficits observed in pathological gambling (PG). This study investigated the role of immediate/delayed sensitivity to reward and punishment, executive functions, impulsivity and explicit knowledge in relation to decision-making performance on the original Iowa Gambling Task (IGT-ABCD) and a variant (IGT-EFGH). METHODS: We assessed 131 consecutive patients with a diagnosis of PG by using executive functioning and decision-making tasks, self-report measures of impulsivity and explicit knowledge. RESULTS: the majority of pathological gamblers (PGs) showed deficits in decision-making, characterized mainly by myopia for the future. Decisions made under risk showed different predictors. Performance on the IGT-ABCD for decisions made under risk was predicted by medium and high levels of explicit knowledge of the task, as well as by scores on the Disorderliness subscale and the degree of Stroop interference. By contrast, IGT-EFGH results were only associated with self-report impulsivity measures. CONCLUSIONS: Decision making in PG involves distinct patterns of deficits, and the predictors differ depending on the reinforcement schedule. Decisions made under risk on the IGT-ABCD are associated with explicit knowledge, executive functions and impulsivity traits related to conscious awareness and control processes. On the IGT-EFGH, however, only impulsivity traits predict decision making.

Impairment in decision-making is frequently observed in suicide attempters. Little is known, however, about neural circuitry underlying decision-making in adolescent attempters. Functional magnetic resonance imaging (fMRI) was used to assess decision-making and learning-related neural activity during Iowa Gambling Task (IGT) performance in adolescents with depression and suicide attempt (ATT, n=15), non-attempters with depression (NAT, n=14), and healthy controls (HC, n=13). ATT performed best on the IGT. A three group by two condition (high-risk versus low-risk) by three IGT block (each of 20 cards) whole-brain analysis (p

Impairment in decision-making is frequently observed in suicide attempters. Little is known, however, about neural circuitry underlying decision-making in adolescent attempters. Functional magnetic resonance imaging (fMRI) was used to assess decision-making and learning-related neural activity during Iowa Gambling Task (IGT) performance in adolescents with depression and suicide attempt (ATT, n=15), non-attempters with depression (NAT, n=14), and healthy controls (HC, n=13). ATT performed best on the IGT. A three group by two condition (high-risk versus low-risk) by three IGT block (each of 20 cards) whole-brain analysis (p

OBJECTIVE: Little is known about the neurobiology of bipolar II disorder. While bipolar I disorder is associated with abnormally elevated activity in response to reward in the ventral striatum, a key component of reward circuitry, no studies have compared reward circuitry function in bipolar I and bipolar II disorders. Furthermore, associations among reward circuitry activity, reward sensitivity, and striatal volume remain underexplored in bipolar and healthy individuals. The authors examined reward activity in the ventral striatum in participants with bipolar I and II disorders and healthy individuals, the relationships between ventral striatal activity and reward sensitivity across all participants, and between-group differences in striatal gray matter volume and relationships with ventral striatal activity across all participants. METHOD: Twenty healthy comparison subjects and 32 euthymic bipolar I (N=17) and bipolar II (N=15) patients underwent a neuroimaging reward paradigm during functional MRI scanning, structural scanning, and completed psychometric and clinical assessments. RESULTS: Region-of-interest analyses revealed significant ventral striatal activity in all participants during reward anticipation that was significantly greater in bipolar II patients compared with the other groups. Ventral striatal activity during reward anticipation correlated positively with reward sensitivity and fun seeking across all participants. Bipolar II patients had significantly greater left putamen volume than bipolar I patients, and left putamen volume correlated positively with left ventral striatal activity to reward anticipation in all participants. CONCLUSIONS: Abnormally elevated ventral striatal activity during reward anticipation may be a potential biomarker of bipolar II disorder. These findings highlight the importance of adopting a dimensional approach in the study of neural mechanisms supporting key pathophysiological processes that may cut across psychiatric disorders.

Individuals have difficulty controlling their food consumption, which is due in part to the ubiquity of tempting food cues in the environment. Individual differences in the propensity to attribute incentive (motivational) salience to and act on these cues may explain why some individuals eat more than others. Using fMRI in healthy women, we found that food cue related activity in the nucleus accumbens, a key brain region for food motivation and reward, was related to subsequent snack food consumption. However, both nucleus accumbens activation and snack food consumption were unrelated to self-reported hunger, or explicit wanting and liking for the snack. In contrast, food cue reactivity in the ventromedial prefrontal cortex was associated with subjective hunger/appetite, but not with consumption. Whilst the food cue reactivity in the nucleus accumbens that predicted snack consumption was not directly related to body mass index (BMI), it was associated with increased BMI in individuals reporting low self-control. Our findings reveal a neural substrate underpinning automatic environmental influences on consumption in humans and demonstrate how self-control interacts with this response to predict BMI. Our data provide support for theoretical models that advocate a 'dual hit' of increased incentive salience attribution to food cues and poor self-control in determining vulnerability to overeating and overweight.

Objectives. We aimed at reviewing studies exploring dysfunctional cognitive processes, and their neuroanatomical basis, in suicidal behaviour, and to develop a neurocognitive working model. Methods. A literature search was conducted. Results. Several limitations were found. The main reported neuropsychological findings are a higher attention to specific negative emotional stimuli, impaired decision-making, lower problem-solving abilities, reduced verbal fluency, and possible reduced non-specific attention and reversal learning in suicide attempters. Neuroimaging studies mainly showed the involvement of ventrolateral orbital, dorsomedial and dorsolateral prefrontal cortices, the anterior cingulate gyrus, and, to a lesser extent, the amygdala. In addition, alterations in white matter connections are suggested. Conclusions. These studies support the concept of alterations in suicidal behaviour distinct from those of comorbid disorders. We propose that a series of neurocognitive dysfunctions, some with trait-like characteristics, may facilitate the development of a suicidal crisis during stressful circumstances: (1) an altered modulation of value attribution, (2) an inadequate regulation of emotional and cognitive responses, and (3) a facilitation of acts in an emotional context. This preliminary model may represent a framework for the design of future studies on the pathophysiology, prediction and prevention of these complex human behaviours. © 2011 Informa Healthcare.

Decision-making impairment has been linked to orbitofrontal cortex lesions and to different disorders including substance abuse, aggression and suicidal behavior. Understanding the neurocognitive mechanisms of these impairments could facilitate the development of effective treatments. In the current study, we aimed to explore the neural and cognitive basis of poor decision-making ability associated with the vulnerability to suicidal behavior, a public health issue in most western countries. Twenty-five not currently depressed male patients, 13 of whom had a history of suicidal acts (suicide attempters) and 12 of whom had none (affective controls), performed an adapted version of the Iowa Gambling Task during functional Magnetic Resonance Imaging. Task-related functional Regions-of-Interest were independently defined in 15 male healthy controls performing the same task (Lawrence et al. 2009). In comparison to affective controls, suicide attempters showed 1) poorer performance on the gambling task 2) decreased activation during risky relative to safe choices in left lateral orbitofrontal and occipital cortices 3) no difference for the contrast between wins and losses. Altered processing of risk under conditions of uncertainty, associated with left lateral orbitofrontal cortex dysfunction, could explain the decision-making deficits observed in suicide attempters. These impaired cognitive and neural processes may represent future predictive markers and therapeutic targets in a field where identification of those at risk is poor and specific treatments are lacking. These results also add to our growing understanding of the role of the orbitofrontal cortex in decision-making and psychopathology.

Perception of fearful faces is associated with functional activation of cortico-limbic structures, which has been found altered in individuals with psychiatric disorders such as schizophrenia, autism and major depression. The objective of this study was to isolate the brain response to the features of standardized fearful faces by incorporating principal component analysis (PCA) into the analysis of neuroimaging data of healthy volunteers and individuals with schizophrenia. At the first stage, the visual characteristics of morphed fearful facial expressions (FEEST, Young et al. 2002) were classified with PCA, which produced seven orthogonal factors, with some of them related to emotionally salient facial features (eyes, mouth, brows) and others reflecting non-salient facial features. Subsequently, these PCA-based factors were included into the functional magnetic resonance imaging (fMRI) analysis of 63 healthy volunteers and 32 individuals with schizophrenia performing a task that involved implicit processing of FEEST stimuli. In healthy volunteers, significant neural response was found to visual characteristics of eyes, mouth or brows. In individuals with schizophrenia, PCA-based analysis enabled us to identify several significant clusters of activation that were not detected by the standard approach. These clusters were implicated in processing of visual and emotional information and were attributable to the perception of eyes and brows. PCA-based analysis could be useful in isolating brain response to salient facial features in psychiatric populations.

BACKGROUND: Patients with eating disorders favor immediate gratification and ignore long-term negative consequences. This study investigated decision making in bulimia nervosa using the Iowa Gambling Task (IGT) and skin conductance responses (SCR). METHOD: a total of 26 bulimia nervosa patients and 51 healthy controls took part in this study; 29 patients with anorexia nervosa were included for comparison. RESULTS: Bulimia nervosa patients performed poorly in the IGT, but showed no decrease in anticipatory SCR, whereas a markedly diminished anticipatory SCR was seen in the anorexia nervosa group. CONCLUSIONS: This finding does not support the somatic marker hypothesis. Impaired decision making was associated with obsessive-compulsive traits.

The Iowa Gambling Task (IGT) assesses decision-making under initially ambiguous conditions. Neuropsychological and neuroimaging data suggest, albeit inconsistently, the involvement of numerous prefrontal cortical regions in task performance. To clarify the contributions of different prefrontal regions, we developed and validated a version of the IGT specifically modified for event-related functional magnetic resonance imaging. General decision-making in healthy males elicited activation in the ventromedial prefrontal cortex. Choices from disadvantageous versus advantageous card decks produced activation in the medial frontal gyrus, lateral orbitofrontal cortex (OFC), and insula. Moreover, activation in these regions, along with the pre-supplementary motor area (pre-SMA) and secondary somatosensory cortex, was positively associated with task performance. Lateral OFC and pre-SMA activation also showed a significant modulation over time, suggesting a role in learning. Striato-thalamic regions responded to wins more than losses. These results both replicate and add to previous findings and help to reconcile inconsistencies in neuropsychological data. They reveal that deciding advantageously under initially ambiguous conditions may require both continuous and dynamic processes involving both the ventral and dorsal prefrontal cortex.

In 1994, it was proposed that decision-making requires emotion-related signals, known as somatic markers. In contrast, some authors argued that conscious knowledge of contingencies is sufficient for advantageous decision-making. We aimed to investigate the respective roles of somatic markers and explicit knowledge in decision-making. Thirty healthy volunteers performed the Iowa Gambling Task (IGT). Conscious knowledge was assessed using a sensitive questionnaire and skin conductance responses (SCRs) were recorded. Most participants acquired a preference for advantageous choices during the task and generated larger anticipatory SCRs before disadvantageous relative to advantageous choices. Performance on the IGT and the autonomic response were positively correlated (r = 0.38, p = 0.045). Moreover, there was a statistically significant difference in performance according to conscious awareness (p = 0.009). There was no significant association between level of explicit knowledge and SCR (p = 0.1). Finally, we did not find any interaction between explicit knowledge and performance although a lack of statistical power is not to be excluded. Advantageous decision-making therefore seems to be associated with two distinct, namely implicit and explicit, systems. © 2009 Elsevier Ltd.

This article describes and further validates a standardized symptom-provocation procedure that combines symptom-specific audio instructions and pictures to reliably provoke different kinds of symptom-specific anxiety in obsessive-compulsive disorder, corresponding to its four major symptom dimensions: contamination/washing, obsessions/checking, hoarding and symmetry/order. The Maudsley Obsessive-Compulsive Stimuli Set has excellent convergent and discriminant validity, and it will be a useful resource for OCD researchers.

Preliminary neuroimaging studies suggest that patients with the 'compulsive hoarding syndrome' may be a neurobiologically distinct variant of obsessive-compulsive disorder (OCD) but further research is needed. A total of 29 OCD patients (13 with and 16 without prominent hoarding symptoms) and 21 healthy controls of both sexes participated in two functional magnetic resonance imaging experiments consisting of the provocation of hoarding-related and symptom-unrelated (aversive control) anxiety. In response to the hoarding-related (but not symptom-unrelated) anxiety provocation, OCD patients with prominent hoarding symptoms showed greater activation in bilateral anterior ventromedial prefrontal cortex (VMPFC) than patients without hoarding symptoms and healthy controls. In the entire patient group (n=29), provoked anxiety was positively correlated with activation in a frontolimbic network that included the anterior VMPFC, medial temporal structures, thalamus and sensorimotor cortex. Negative correlations were observed in the left dorsal anterior cingulate gyrus, bilateral temporal cortex, bilateral dorsolateral/medial prefrontal regions, basal ganglia and parieto-occipital regions. These results were independent from the effects of age, sex, level of education, state anxiety, depression, comorbidity and use of medication. The findings are consistent with the animal and lesion literature and several landmark clinical features of compulsive hoarding, particularly decision-making difficulties. Whether the results are generalizable to hoarders who do not meet criteria for OCD remains to be investigated.

BACKGROUND: Obsessive-compulsive disorder (OCD) is a clinically heterogenous disorder characterized by temporally stable symptom dimensions. Past inconsistent results from structural neuroimaging studies of OCD may have resulted from the effects of these specific symptom dimensions as well as other socio-demographic and clinical variables upon gray matter (GM) volume. METHODS: GM volume was measured in 25 adult OCD patients and 20 adult healthy controls using voxel-based morphometry (VBM), controlling for age and total brain GM volume. Univariate and multivariate regression analyses were carried out between regions of GM difference and age, age of onset, medication load, OCD severity, depression severity, and separate symptom dimension scores. RESULTS: Significant GM volumetric differences in OCD patients relative to controls were found in dorsal cortical regions, including bilateral BA6, BA46, BA9 and right BA8 (controls>patients), and bilateral midbrain (patients>controls). Stepwise regression analyses revealed highly significant relationships between greater total OCD symptom severity and smaller GM volumes in dorsal cortical regions and larger GM volumes in bilateral midbrain. Greater age was independently associated with smaller GM volumes in right BA6, left BA9, left BA46 and larger GM volumes in right midbrain. Greater washing symptom severity was independently associated with smaller GM volume in right BA6, while there was a trend association between greater hoarding symptom severity and lower GM volume in left BA6. LIMITATIONS: the sample was relatively small to examine the relationship between symptom scores and GM volumes. Multiple patients were taking medication and had comorbid disorders. CONCLUSIONS: These analyses suggest dorsal prefrontal cortical and bilateral midbrain GM abnormalities in OCD that appear to be primarily driven by the effects of total OCD symptom severity. The results regarding the relationship between GM volumes and symptom dimension scores require examination in larger samples.

BACKGROUND: Depersonalisation disorder is characterised by emotion suppression, but the cerebral mechanisms of this symptom are not yet fully understood. AIMS: to compare brain activation and autonomic responses of individuals with the disorder and healthy controls. METHOD: Happy and sad emotion expressions in increasing intensities (neutral to intense) were presented in an implicit event-related functional magnetic resonance imaging (fMRI) design with simultaneous measurement of autonomic responses. RESULTS: Participants with depersonalisation disorder showed fMRI signal decreases, whereas the control group showed signal increases in response to emotion intensity increases in both happy and sad expressions. The analysis of evoked haemodynamic responses from regions exhibiting functional connectivity between central and autonomic nervous systems indicated that in depersonalisation disorder initial modulations of haemodynamic response occurred significantly earlier (2 s post-stimulus) than in the control group (4-6 s post-stimulus). CONCLUSIONS: the results suggest that fMRI signal decreases are possible correlates of emotion suppression in depersonalisation disorder.

A distributed, serotonergically innervated neural system comprising extrastriate cortex, amygdala and ventral prefrontal cortex is critical for identification of socially relevant emotive stimuli. The extent to which a genetic variation of serotonin transporter gene 5-HTTLPR impacts functional connectivity between the amygdala and the other components of this neural system remains little examined. In our study, neural activity was measured using event-related functional magnetic resonance imaging in 29 right-handed, white Caucasian healthy subjects as they viewed mild or prototypical fearful and neutral facial expressions. 5-HTTLPR genotype was classified as homozygous for the short allele (S/S), homozygous for the long allele (L/L) or heterozygous (S/L). S/S showed greater activity than L/L within right fusiform gyrus (FG) to prototypically fearful faces. To these fearful faces, S/S more than other genotype subgroups showed significantly greater positive functional connectivity between right amygdala and FG and between right FG and right ventrolateral prefrontal cortex (VLPFC). There was a positive association between measure of psychoticism and degree of functional connectivity between right FG and right VLPFC in response to prototypically fearful faces. Our data are the first to show that genotypic variation in 5-HTTLPR modulates both the amplitude within and the functional connectivity between different components of the visual object-processing neural system to emotionally salient stimuli. These effects may underlie the vulnerability to mood and anxiety disorders potentially triggered by socially salient, emotional cues in individuals with the S allele of 5-HTTLPR.

Little is known about how individual differences in trait disgust sensitivity modulate the neural responses to disgusting stimuli in the brain. Thirty-seven adult healthy volunteers completed the Disgust Scale (DS) and viewed alternating blocks of disgusting and neutral pictures from the International Affective Picture System while undergoing fMRI scanning. DS scores correlated positively with activations in brain regions previously associated with disgust (anterior insula, ventrolateral prefrontal cortex-temporal pole, putamen-globus pallidus, dorsal anterior cingulate, and visual cortex) and negatively with brain regions involved in the regulation of emotions (dorsolateral and rostral prefrontal cortices). The results were not confounded by biological sex, anxiety or depression scores, which were statistically controlled for. Disgust sensitivity, a behavioral trait that is normally distributed in the general population, predicts the magnitude of the individual's neural responses to a broad range of disgusting stimuli. The results have implications for disgust-related psychiatric disorders.

The objective of this study is to determine (a) if decision making ability is impaired in patients with anorexia nervosa (AN) and in people with good recovery from AN and (b) whether any impairment in decision making is associated with alterations in skin conductance responses (SCR). Patients with AN (n = 29), healthy controls comparable in age and IQ (HC, n = 29), and women long term recovered from AN (n = 14), completed the Iowa Gambling Task (IGT) while their SCR were measured. AN patients performed poorly in the IGT compared to the HC and to the recovered AN participants. AN patients had decreased anticipatory SCR prior to choosing cards and reduced SCR after losses compared to HC. IGT performance and the SCR of recovered AN participants did not differ from the HC. Decision making ability is impaired in AN. It is associated with a significantly attenuated SCR. Neither of these features are found in recovered AN. The association between impaired decision making ability and a decreased autonomic response is consistent with the predictions of the Somatic Marker Hypothesis.

Background: Washing symptoms in Obsessive-Compulsive Disorder (OCD) are associated with increased trait sensitivity to disgust. This study explored neural systems underlying sensitivity to symptom-unrelated disgust and fear in OCD using functional neuroimaging. Methods: Seventeen OCD subjects and 19 controls viewed facial expressions of disgust and fear (versus neutral) presented just above the level of conscious awareness in a backward masking paradigm. Results: the OCD group showed greater activation than controls in the left ventrolateral prefrontal cortex, but reduced activation in the thalamus, to facial expressions of disgust. There were no between-group differences in response to fear. Further analysis using a median-split to divide OCD subjects into high and low washers suggested that the enhanced ventrolateral prefrontal cortex response was being driven by predominantly female OCD subjects with high washing symptoms. These subjects also reported higher levels of trait sensitivity to disgust. Conclusions: These findings are consistent with previous reports of increased response to symptom-relevant and generally disgusting stimuli in neural regions associated with disgust and autonomic response processing in OCD patients with prominent washing symptoms. Together, these findings point to increased sensitivity to disgust stimuli as a component of the pathophysiology of the washing/contamination symptom dimension of OCD. © 2007 Society of Biological Psychiatry.

BACKGROUND: a majority of patients with disgust-related psychiatric disorders such as animal phobias and contamination-related obsessive-compulsive disorder are women. The aim of this functional magnetic resonance imaging (fMRI) study was to examine possible sex differences in neural responses to disgust-inducing stimuli that might help explain this female predominance. METHODS: Thirty-four healthy adult volunteers (17 women, all right-handed) were scanned while viewing alternating blocks of disgusting and neutral pictures from the International Affective Picture System. Using a partially-silent fMRI sequence, the participants rated their level of discomfort after each block of pictures. Skin conductance responses (SCR) were measured throughout the experiment. All participants completed the Disgust Scale. RESULTS: Both women and men reported greater subjective discomfort and showed more SCR fluctuations during the disgusting picture blocks than during the neutral picture blocks. Women and men also demonstrated a similar pattern of brain response to disgusting compared with neutral pictures, showing activation in the anterior insula, ventrolateral and dorsolateral prefrontal cortices, and visual regions. Compared with men, women had significantly higher disgust sensitivity scores, experienced more subjective discomfort, and demonstrated greater activity in left ventrolateral prefrontal regions. However, these differences were no longer significant when disgust sensitivity scores were controlled for. CONCLUSIONS: in healthy adult volunteers, there are significant sex-related differences in brain responses to disgusting stimuli that are irrevocably linked to greater disgust sensitivity scores in women. The implications for disgust-related psychiatric disorders are discussed.

Obsessive-compulsive disorder (OCD) is clinically heterogeneous. The authors examined how specific OCD symptom dimensions were related to neuropsychological functions using multiple regression analyses. A total of 39 OCD patients and 40 controls completed the Iowa Gambling Task (IGT; A. Bechara, A. R. Damasio, H. Damasio, & S. W. Anderson, 1994), which is a test of decision making, and the Wisconsin Card Sorting Test (R. K. Heaton, 1981), which is a test of set shifting. OCD patients and controls showed comparable decision making. However, patients with prominent hoarding symptoms showed impaired decision making on the IGT as well as reduced skin conductance responses. OCD patients had poorer set shifting abilities than controls, and symmetry/ordering symptoms were negatively associated with set shifting. These results help explain previous inconsistent findings in neuropsychological research in OCD and support recent neuroimaging data showing dissociable neural mechanisms involved in mediating the different OCD symptom dimensions.

The neural basis of human attachment security remains unexamined. Using event-related functional magnetic resonance imaging (fMRI) and simultaneous recordings of skin conductance levels, we measured neural and autonomic responses in healthy adult individuals during a semantic conceptual priming task measuring human attachment security "by proxy". Performance during a stress but not a neutral prime condition was associated with response in bilateral amygdalae. Furthermore, levels of activity within bilateral amygdalae were highly positively correlated with attachment insecurity and autonomic response during the stress prime condition. We thereby demonstrate a key role of the amygdala in mediating autonomic activity associated with human attachment insecurity.

Objectives: Bipolar patients are impaired in Stroop task performance, a measure of selective attention. Structural and functional abnormalities in task-associated regions, in particular the prefrontal cortex (PFC), have been reported in this population. We aimed to examine the relationship between functional abnormalities, impaired task performance and the severity of depressive symptoms in bipolar patients. Methods: Remitted bipolar patients (n = 10; all medicated), either euthymic or with subsyndromal depression, and age-matched control subjects (n = 11) viewed 10 alternating blocks of incongruent Stroop and control stimuli, naming the colour of the ink. Neural response was measured using functional magnetic resonance imaging. We computed between-group differences in neural response and within-group correlations with mood and anxiety. Results: There were no significant between-group differences in task performance. During the Stroop condition, controls demonstrated greater activation of visual and dorsolateral and ventrolateral prefrontal cortical areas; bipolar patients demonstrated relative deactivation within orbital and medial prefrontal cortices. Depression scores showed a trend towards a negative correlation with the magnitude of orbitofrontal cortex deactivation in bipolar patients, whereas state anxiety correlated positively with activation of dorsolateral PFC and precuneus in controls. Conclusions: Our findings confirm previous reports of decreased ventral prefrontal activity during Stroop task performance in bipolar patients, and suggest a possible negative correlation between this and depression severity in bipolar patients. These findings further highlight the ventromedial PFC as a potential candidate for illness related dysfunction in bipolar disorder. © Blackwell Munksgaard, 2006.

CONTEXT: Obsessive-compulsive disorder (OCD) is clinically heterogeneous, yet most previous functional neuroimaging studies grouped together patients with mixed symptoms, thus potentially reducing the power and obscuring the findings of such studies. OBJECTIVE: to investigate the neural correlates of washing, checking, and hoarding symptom dimensions in OCD. DESIGN: Symptom provocation paradigm, functional magnetic resonance imaging, block design, and nonparametric brain mapping analyses. SETTING: University hospital. PARTICIPANTS: Sixteen patients with OCD (11 inpatients, 5 outpatients) with mixed symptoms and 17 healthy volunteers of both sexes. Intervention all subjects participated in 4 functional magnetic resonance imaging experiments. They were scanned while viewing alternating blocks of emotional (washing-related, checking-related, hoarding-related, or aversive, symptom-unrelated) and neutral pictures, and imagining scenarios related to the content of each picture type.Main Outcome Measure Blood oxygenation level-dependent response. RESULTS: Both patients and control subjects experienced increased subjective anxiety during symptom provocation (patients significantly more so) and activated neural regions previously linked to OCD. Analyses of covariance, controlling for depression, showed a distinct pattern of activation associated with each symptom dimension. Patients demonstrated significantly greater activation than controls in bilateral ventromedial prefrontal regions and right caudate nucleus (washing); putamen/globus pallidus, thalamus, and dorsal cortical areas (checking); left precentral gyrus and right orbitofrontal cortex (hoarding); and left occipitotemporal regions (aversive, symptom-unrelated). These results were further supported by correlation analyses within patients, which showed highly specific positive associations between subjective anxiety, questionnaire scores, and neural response in each experiment. There were no consistently significant differences between patients with (n = 9) and without (n = 7) comorbid diagnoses. CONCLUSIONS: the findings suggest that different obsessive-compulsive symptom dimensions are mediated by relatively distinct components of frontostriatothalamic circuits implicated in cognitive and emotion processing. Obsessive-compulsive disorder may be best conceptualized as a spectrum of multiple, potentially overlapping syndromes rather than a unitary nosologic entity.

BACKGROUND: Bipolar disorder (BD) is characterised by abnormalities in mood and emotional processing, but the neural correlates of these, their relationship to depressive symptoms, and the similarities with deficits in major depressive disorder (MDD) remain unclear. We compared responses within subcortical and prefrontal cortical regions to emotionally salient material in patients with BP and MDD using functional magnetic resonance imaging. METHODS: We measured neural responses to mild and intense expressions of fear, happiness, and sadness in euthymic and depressed BD patients, healthy control subjects, and depressed MDD patients. RESULTS: Bipolar disorder patients demonstrated increased subcortical (ventral striatal, thalamic, hippocampal) and ventral prefrontal cortical responses particularly to mild and intense fear, mild happy, and mild sad expressions. Healthy control subjects demonstrated increased subcortical responses to intense happy and mild fear, and increased dorsal prefrontal cortical responses to intense sad expressions. Overall, MDD patients showed diminished neural responses to all emotional expressions except mild sadness. Depression severity correlated positively with hippocampal response to mild sadness in both patient groups. CONCLUSIONS: Compared with healthy controls and MDD patients, BD patients demonstrated increased subcortical and ventral prefrontal cortical responses to both positive and negative emotional expressions.

Background: Some multiple sclerosis (MS) patients treated with interferon beta (IFN β) develop antibodies to the drug. Neutralising antibody (NAB) assays for IFN β are expensive and the clinical relevance of the results has been debated. Objective: to establish a cheap, sensitive, and reliable assay for antibodies to 125|-|FN β, and to correlate levels of antibodies with clinical response to IFN β treatment. Methods: We established a radioimmunoprecipitation assay (RIPA) using 125|-|FN β. We tested NAB positive sera, healthy control sera, and serial samples of 33 IFN β-1b treated MS patients from the Vancouver cohort of the Berlex pivotal trial who had a high incidence of NABs. Results: We found that the RIPA was highly sensitive for the detection of antibodies to IFN β-1a and -1b, and that there was a strong correlation between reactivity of NAB positive sera for 125|-|FN β-1b and for 125|-|FN β-1a. The RIPA was more sensitive and consistent than the NAB. Moreover, there was a trend towards poorer MRI outcomes in RIPA positive patients, but not in NAB-positive patients. Conclusions: the RIPA assay is sensitive and easy to perform. It should be of value in assessing the clinical impact of IFN β antibodies, and its use could help target expensive INF β treatments to those who will respond best.

Latent inhibition describes a process of learning to ignore stimuli of no consequence, and is disrupted in acute, positive-symptomatic schizophrenia. Understanding the neural basis of latent inhibition in animals may help to elucidate the neural dysfunction underlying positive schizophrenic symptoms in man. Evidence suggests a crucial role for dopamine transmission in the nucleus accumbens in the control of latent inhibition. The present studies investigated the role of the GABA-ergic efferent from the nucleus accumbens to the ventral pallidum in latent inhibition. The GABA(A) agonist muscimol (4.56 ng/microl), and antagonist picrotoxin (0.2 microg/microl), were infused into the ventral pallidum, and effects on latent inhibition were assessed using a conditioned suppression procedure. Neither drug produced specific effects on latent inhibition when given alone and, in the case of muscimol, failed to reverse the disruption of latent inhibition induced by systemic amphetamine. In addition to significant non-specific drug effects, a positive control experiment revealed that intra-pallidal picrotoxin significantly enhanced locomotion, suggesting that our manipulations of ventral pallidal GABA function were behaviourally effective. We conclude that modulating ventral pallidal GABA transmission does not affect latent inhibition. The implications of this finding for theories of the neural circuitry mediating latent inhibition and for understanding the functional role of ventral pallidal GABA transmission are discussed.

Sustained attention deficits occur in several neuropsychiatric disorders. However, the underlying neurobiological mechanisms are still incompletely understood. To that end, functional MRI was used to investigate the neural substrates of sustained attention (vigilance) using the rapid visual information processing (RVIP) task in 25 healthy volunteers. In order to better understand the neural networks underlying attentional abilities, brain regions where task-induced activation correlated with task performance were identified. Performance of the RVIP task activated a network of frontal, parietal, occipital, thalamic, and cerebellar regions. Deactivation during task performance was seen in the anterior and posterior cingulate, insula, and the left temporal and parahippocampal gyrus. Good task performance, as defined by better detection of target stimuli, was correlated with enhanced activation in predominantly right fronto-parietal regions and with decreased activation in predominantly left temporo-limbic and cingulate areas. Factor analysis revealed that these performance-correlated regions were grouped into two separate networks comprised of positively activated and negatively activated intercorrelatecl regions. Poor performers failed to significantly activate or deactivate these networks, whereas good performers either activated the positive or deactivated the negative network, or did both. The fact that both increased activation of task-specific areas and increased deactivation of task-irrelevant areas mediate cognitive functions underlying good RVIP task performance suggests two independent circuits, presumably reflecting different cognitive strategies, can be recruited to perform this vigilance task.

Understanding nicotine's neurobiological and cognitive mechanisms may help explain both its addictive properties and potential therapeutic applications. As such, functional MRI was used to determine the neural substrates of nicotine's effects on a sustained attention (rapid visual information-processing) task. Performance was associated with activation in a fronto-parietal-thalamic network in both smokers and nonsmokers. Along with subtle behavioral deficits, mildly abstinent smokers showed less task-induced brain activation in the parietal cortex and caudate than did nonsmokers. Transdermal nicotine replacement improved task performance in smokers and increased task-induced brain activation in the parietal cortex, thalamus, and caudate, while nicotine induced a generalized increase in occipital cortex activity. These data suggest that nicotine improves attention in smokers by enhancing activation in areas traditionally associated with visual attention, arousal, and motor activation.

Two different current views hold that the mesolimbic dopaminergic projection to the nucleus accumbens mediates (1) the behavioral effects of reward or positive incentive motivation and (2) the cognitive functions that go awry in acute schizophrenia. These two views are difficult to integrate with each other. The former view fits better with the established role that the nucleus accumbens plays in the motor programming circuitry of the basal ganglia; but it fits poorly with evidence that dopamine release is provoked in the nucleus accumbens not only by rewarding, but also by aversive, stimuli. We review evidence, especially from experiments using the prepulse and latent inhibition paradigms, consistent with a role for the mesolimbic dopaminergic pathway in the cognitive dysfunctions of schizophrenia. We also propose a new model for the functions of this pathway which draws on recent evidence that the nucleus accumbens has outputs to perceptual as well as motor systems. The model is able in principle to account for the data sets that support both major current views of the functions of the mesolimbic dopaminergic system. It has not yet received support, however, from direct experimental tests.