Dr Leor Roseman

About me:

I am a Senior Lecturer and Psychedelic Researcher at the department of psychology. I am fascinated by the ways psychedelics modify consciousness from a biopsychosocial perspective. I have previously worked at the Centre for Psychedelic Research, Imperial College London, 2013-2023, under the mentorship of Prof. Robin Carhart-Harris and Prof. David Nutt. I have been in the midst of a so-called psychedelic revolution, supporting the foundational work of a re-emerging research field.

My interdisciplinary research covers neuroscience, psychology, phenomenology, anthropology and conflict resolution, using a wide array of research methods such as fMRI, quantitative, qualitative, microphenomenology, ethnographic, and participatory research.

Research Interests:

• The communal and social use of psychedelics. I am interested in how psychedelics enhance connectedness, group bonding (communitas), sociality, and can serve as a social cure.
• The potential use of psychedelics for peacebuilding. I study ayahuasca groups of Israelis and Palestinians. In an ethnographic-phenomenological work, I described intense moments of group unity and identity dissolution; awe-inspiring moments of interfaith and intercultural connection and recognition through music and prayers; and visions of collective trauma and the trauma of the other. From a critical perspective, I argue that too strong of an emphasis on oneness and harmony can preserve the status quo of inequality towards Palestinians by silencing conflictual voices. However, sometimes revelatory events can reveal tensions related to inequality and injustice and motivate people towards changing the status-quo. I am currently working with a group of Palestinian and Israeli activists to create a psychedelic peacebuilding program, and we piloted several such retreats.
• The neural correlates of the psychedelic state. I am interested in the relation between the psychedelic experience and its neural correlates. Notably, I showed in fMRI how communication patterns increase between usually segregated networks – a result that many labs have replicated since my original publication. I am involved in many other neuroscientific projects, collaborating with a wide network of researchers. 
• The role of the visual cortex in psychedelic imagery. I argue that a core feature of the psychedelic state is enhanced dialogical processes between the visual cortex and higher-level regions.
• The therapeutic potential of the psychedelic experience. I showed how different psychedelic experiences - such as peak/mystical experiences, emotional breakthroughs, and communitas – relate to long-term clinical changes.
• Phenomenology. As an enthusiast psychonaut, I am fascinated by the psychedelic experience. I have used micro-phenomenology to study the experience and developed several questionnaires to quantify it.

Teaching: 

I co-developed and am teaching in MSc Psychedelics: Mind, Medicine, and Culture (on-campus or online) together with Peter Sjostedt-Hughes, Andy Lecther, Christine Hauskeller, Simon Ruffell, Anjali Bhat, and Celia Morgan (see PGCert for thought modules without thesis). We have created these exciting courses, weaving knowledge from diverse disciplines such as philosophy, psychology, neuroscience, anthropology, and religious studies. We have put a lot of care into this course, and we are quite proud of the outcome. 

Career:

2013-2023: Centre for Psychedelic Research, Imperial College London
MRes, PhD, Postdoc & Research Fellow
Mentored by Prof. Robin Carhart-Harris & Prof. David Nutt

Founder and Director of Ripples Alliance, a non-profit dedicated to peacebuilding supported by psychedelics
https://ripplesalliance.org/

Art

In collaboration with past participants in my peacebuilding research, we created a performance titled Collective Liberation Ritual (featured in the Financial Times). We performed at Medicine Festival, London, Davos, Denver, and Oxford. The Collective Liberation Ritual is partly a performance and partly a process, held by Palestinian and Israeli musicians, facilitators, educators, and peace activists. The performance includes storytelling, facilitated processes, theatre, dance, and music – and carries the audience through grief into solidarity and empowerment. 

Selected Papers:

• Pronovost-Morgan, C., Greenway, K., & Roseman, L. (2025). The Reporting of Setting in Psychedelic Clinical Trials (ReSPCT) Guidelines: An international Delphi consensus study. Nature Medicine
• Newson, M., Haslam, A., Haslam, C., Cruwys, T., & Roseman, L. (2024). Social identity processes as a vehicle for therapeutic success in psychedelic treatment: harnessing the social cure. Nature Mental Health.
• Roseman, L. (2024). A reflection on paradigmatic tensions within the FDA advisory committee for MDMA-assisted therapy. Journal of Psychopharmacology.
• Roseman, L. (2024). An Imaginary Interview with Martin Buber About Psychedelics. Voices: The Art and Science of Psychotherapy.
• Timmermann, C., Roseman, L., Haridas, S., Rosas, F., Luan, L., Kettner, H… & Carhart-Harris, R. (2023). Human Brain Effects of DMT determined via fMRI-EEG. PNAS
• Roseman, L., & Karkabi, N. (2021). On revelations and revolutions: drinking Ayahuasca among Palestinians under Israeli occupation. Frontiers in Psychology.
• Roseman, L., Ron, Y., Saca, A., Ginsberg, N., Luan, L., Karkabi, N., Doblin, R., & Carhart-Harris, R. (2021). Relational processes in ayahuasca groups of Palestinians and Israelis. Frontiers in Pharmacology.
• Watts, R., Kettner, H., Geerts, D., Gandy, S., Kartner, L., Mertens, L., Timmermann, C., Nour, M., Kaelen, M., Nutt, D., Carhart-Harris, R. & Roseman, L. (2022). The Watts Connectedness Scale: a new scale for measuring a sense of connectedness to self, others, and world. Psychopharmacology
• Kettner, H., Rosas, F. E., Timmermann, C., Kärtner, L., Carhart-Harris, R. L., & Roseman, L. (2021). Psychedelic communitas: intersubjective experience during psychedelic group sessions predicts enduring changes in psychological wellbeing and social connectedness. Frontiers in Pharmacology.
• Roseman, L., Haijen, E., Idialu-Ikato, K., Kaelen, M., Watts, R., & Carhart-Harris, R. (2019). Emotional breakthrough and psychedelics: Validation of the Emotional Breakthrough Inventory. Journal of Psychopharmacology. 
• Carhart-Harris, R. L., Roseman, L., Haijen, E., Erritzoe, D., Branchi, I., & Kaelen, M. (2018). Psychedelics and the essential importance of context. Journal of Psychopharmacology. 
• Roseman, L., Nutt, D. J., & Carhart-Harris, R. L. (2017). Quality of acute psychedelic experience predicts therapeutic efficacy of psilocybin for treatment-resistant depression. Frontiers in Pharmacology.
• Carhart-Harris, R. L., Muthukumaraswamy, S., Roseman, L., Kaelen, M., Droog, W., Murphy, K., ... & Nutt, D.J. (2016). Neural correlates of the LSD experience revealed by multimodal neuroimaging. PNAS.
• Roseman, L., Leech, R., Feilding, A., Nutt, D. J., & Carhart-Harris, R. L. (2014). The effects of psilocybin and MDMA on between-network resting state functional connectivity in healthy volunteers. Frontiers in Human Neuroscience. 

Selected Lectures

• From personal to collective: ayahuasca as a peace-making tool among Palestinians and Israelis. With Sami Awad. Psychedelic Science, Denver, 2023
• Messianic Mystics: When Spirituality and Politics Meet. Breaking Convention, Exeter, 2023. 
• How Psychedelics Spread: The Sociopolitical Dynamics of Psychedelic Diffusion. ICPR, Netherlands, 2024