Profile
Richard Zeifman is an Assistant Professor of Psychology (Clinical) and Director of the Psychedelic-Assisted THerapy (PATH) Lab at The New School for Social Research.
Richard's research focuses on examining the safety, efficacy, and mechanisms of change underlying psychedelic therapy. He conducts clinical trials, real-world effectiveness studies, and uses multi-method approaches to study, and elucidate the mechanisms underlying, psychedelic therapy for the treatment of psychiatric disorders. He is a co-investigator on several clinical trials examining psychedelic-assisted therapy for the treatment of major depressive disorder, cancer-related distress, and posttraumatic stress disorder (PTSD).
Degrees Held
BA 2015, York University
MA 2017, Toronto Metropolitan University
PhD 2022, Toronto Metropolitan University
Recent Publications
Google Scholar Page
Gordon, A. R., Carrithers, B. M., Pagni, B., Kettner, H., Marrocu, A., Nayak, S., Weiss, B. J., Carhart-Harris, R. L., Roberts, D. E., Erritzoe, D., Garcia-Romeu, A., Jackson, H., Lowe, M. X., & Zeifman, R. J. (in press). The effect of psychedelics on individuals with a personality disorder: Results from two prospective cohort studies. Psychedelic Medicine.
Agin-Liebes, G., Zeifman, R. J., & Mitchel, J. M. (2025). Self-compassion mediates treatment effects in MDMA-assisted therapy for posttraumatic stress disorder. European Journal of Psychotraumatology, 16(1), 2485513. https://doi.org/10.1080/20008066.2025.2485513
Carrithers, B. M., Roberts, D. E., Weiss, B. J., King, J. D., Carhart-Harris, R. L., Gordon, A. R., Pagni, B. A., Moreau, M., Ross, S., & Zeifman, R. J. (2025). Exploring serotonergic psychedelics as a treatment for personality disorders. Neuropharmacology, 272, 110413. https://doi.org/10.1016/j.neuropharm.2025.110413
Zeifman, R. J., Spriggs, M. J., Kettner, H., Lyons, T., Rosas, F., Mediano, P., Erritzoe, D., & Carhart-Harris, R. (2025). From relaxed beliefs under psychedelics (REBUS) to revised beliefs after psychedelics (REBAS). Scientific Reports, 15, 3651. https://doi.org/10.1038/s41598-023-28111-3
Pagni, B. A., Zeifman, R. J., Mennenga, S. E., Carrithers, B., Goldway, N., Bhatt, S., O’Donnell, K. C., Ross, S., & Bogenschutz, M. P. (2025). Multi-dimensional personality changes following psilocybin-assisted therapy in patients with alcohol use disorder: Results from a double-blind, randomized, placebo-controlled trial. American Journal of Psychiatry, 182(1), 114-125. https://doi.org/10.1176/appi.ajp.20230887
Petridis P. D., Grinband, J., Agin-Liebes, G., Kinslow C. J., Zeifman, R. J., Griffiths, R. R., & Ross, S. (2024). Psilocybin-assisted psychotherapy improves psychiatric symptoms across multiple dimensions in patients with cancer. Nature Mental Health, 2, 1408-1414. https://doi.org/10.1038/s44220-024-00331-0
Sloshower, J., Zeifman, R. J., Guss, J., Krause, R., Safi-Aghdam, H., Pathania, S., Pittman, B., & D’Souza, D. C. (2024). Psychological flexibility as a mechanism of change in psilocybin-assisted therapy for major depression: Results from an exploratory placebo-controlled trial. Scientific Reports, 14, 8833. https://doi.org/10.1038/s41598-024-58318-x
Zeifman, R. J., Hernandez, K. M., Song, J., Liebman, R. E., Ip, J., Burdo, J., Johnson, C.,Wiltsey Stirman, S., & Monson, C. M. (2024). Which PTSD clusters and symptoms are central to reducing suicidal ideation? A network and cross-lagged analysis among individuals receiving cognitive processing therapy. European Journal of Psychotraumatology, 15(1), 2434315. https://doi.org/10.1080/20008066.2024.2434315
Zeifman, R. J., Kettner, H., Ross, S., Weiss, B., Mithoefer, M. C., Mithoefer, A. T., & Wagner, A. C. (2024). Preliminary evidence for the importance of therapeutic alliance in MDMA-assisted psychotherapy for posttraumatic stress disorder. European Journal of Psychotraumatology, 15(1), 2297536. https://doi.org/10.1080/20008066.2023.2297536
Zeifman, R. J., & Maia, L. O. (2024). Methodological concerns in psychedelic research: The issues of nonequivalent psychological support and generalizability. European Neuropsychopharmacology, 78, 13-15. https://doi.org/10.1016/j.euroneuro.2023.09.007
Zeifman, R. J., Kettner, H., Pagni, B. A., Mallard, A.,* Roberts, D. E., Erritzoe, D., & Carhart-Harris, R., L. (2023). Co-use of MDMA with psilocybin/LSD may buffer against challenging experiences and enhance positive experiences. Scientific Reports, 13, 13645. https://doi.org/10.1038/s41598-023-40856-5
Zeifman, R. J., Dengdeng, Y., Singhal, N., Wang, G., Nayak, S. M., & Weisman, C. R. (2022). Decreases in suicidality following psychedelic therapy: A meta-analysis of individual patient data across clinical trials. The Journal of Clinical Psychiatry, 83(2), 39235. https://doi.org/10.4088/JCP.21r14057
Zeifman, R. J., Landy, M. S. H., Liebman, R., Fitzpatrick, S., & Monson, C. M. (2021). Optimizing treatment for comorbid borderline personality disorder and posttraumatic stress disorder: A systematic review of psychotherapeutic approaches and treatment efficacy. Clinical Psychology Review, 86, 102030. https://doi.org/10.1016/j.cpr.2021.102030
Zeifman, R. J., Singhal, N., Breslow, L., & Weisman, C. R. (2021). On the relationship between classic psychedelics and suicidality: A systematic review. ACS Pharmacology & Translational Science, 4(2), 436-451. https://doi.org/10.1021/acsptsci.1c00024
Zeifman, R. J., Wagner, A. C., Monson, C. M., & Carhart-Harris, R. (2023). How does psilocybin therapy work? An exploration of experiential avoidance as a putative mechanism of change. Journal of Affective Disorders, 334, 100-112. https://doi.org/10.1016/j.jad.2023.04.105
Research Interests
Psychedelic-assisted therapy, mechanisms of change, posttraumatic stress disorder, suicide, borderline personality disorder