Skip to main content

PHRI News & Events

Clinical trials and other studies examining the use of psilocybin to treat phantom-limb pain and other health conditions are currently in development. To stay up to date on PHRI research and programs, please sign up for our mailing list here.

Latest News:


The Psychedelics and Health Research Initiative at UC San Diego is excited to conduct the first randomized, placebo-controlled human clinical trial examining the efficacy of psilocybin in patients suffering from chronic phantom-limb pain. This research would not be possible without the support of the Steven & Alexandra Cohen Foundation, for which we are deeply grateful, and the interdisciplinary culture of UC San Diego, enabling this collaboration between UC San Diego Health, the Qualcomm Institute, the UCSD Center for Mindfulness, departments of Anesthesia and Psychiatry, and The Arthur C. Clarke Center for Human Imagination, among others.

Do you have chronic phantom-limb pain?

Recruitment for this study is currently taking place. Scan the below QR code if you would like to discuss and learn more. Or contact us at or 619-432-5278.


Past Webinars and Events:

Psychedelic-Assisted Therapy: The National and Local Movement

November 19, 2020, from 3–4pm PST

Research on psychedelics has taken place for years at UC San Diego, but with the launch of the Psychedelics and Health Research Initiative earlier this year, a new phase in the clinical study of psychedelics—to understand their basic mechanisms and their potential uses to treat chronic pain and other ailments—joins the national resurgence under the leadership of Mark Geyer and Adam Halberstadt. David Bronner, CEO of Dr. Bronner’s Magic Soaps (based in North County, San Diego), has been a longtime advocate and ally of the movement to re-examine the use of psychedelics, serving as a board member of MAPS (the Multidisciplinary Association for Psychedelic Studies) among other activities. We invite you to join us for a conversation between Mark, Adam, and David, hosted and moderated by Cassi Vieten, about how the field has developed over the last ten years through the collaborative efforts of academic and private institutions, and what the future of psychedelic-assisted therapies may look like in the next ten years.

David Bronner is Cosmic Engagement Officer (CEO) of Dr. Bronner’s, the top-selling natural brand of soap in North America and producer of a range of organic body care and food products. He is a grandson of company founder, Emanuel Bronner, and a fifth-generation soapmaker. David and Michael established Dr. Bronner’s as a sustainable leader in the natural products industry by becoming one of the first body care brands to formulate with hemp seed oil in 1999 and to certify its soaps, lotions, balms, and other personal care products under the USDA National Organic Program in 2003. Today, David is helping to lead the effort to establish the Regenerative Organic Certified standard, dedicating time and resources to creating an integrated, comprehensive program that addresses soil health, animal welfare, and fair labor practices to advance sustainable and ecological alternatives to industrial agriculture. In addition to his support of advocacy for regenerative organic agriculture, David directs Dr. Bronner’s resources to support animal advocacy, wage equality, and drug policy reform. One of his passions is the responsible integration of cannabis and psychedelic medicine into American and global culture and he is a board member of the Multi-Disciplinary Association of Psychedelic Studies. His activism embodies the company’s mission — which encompasses a commitment to making socially and environmentally responsible products of the highest quality, and to dedicating profits to help make a better world. David was born in Los Angeles, California in 1973 and earned an undergraduate degree in biology from Harvard University. He is a dedicated vegan and enjoys surfing and dancing late into the night. He currently lives in Encinitas, California.

Mark A. Geyer Ph.D. is Co-Director of the PHRI and Distinguished Professor of Psychiatry and Neurosciences Emeritus at the University of California San Diego, where he directs the Neuropsychopharmacology Unit of the VISN 22 VA’s Mental Illness Research, Clinical, and Education Center. Since receiving his doctorate in Psychology in 1972, he has focused on basic research addressing the behavioral and neurobiological effects of psychedelics and other psychoactive drugs.  For four decades, his group has had continuous funding from the National Institute on Drug Abuse to study the behavioral effects of hallucinogens. In 1993, he co-founded the Heffter Research Institute, which pioneered and supported much of the scientific research that has prompted the exploration of psychedelics as potential therapeutics in humans.  Dr. Geyer is recognized internationally for his research on the psychophysiology, neurobiology, and pharmacotherapy of schizophrenia and bipolar disorder.  He has published over 470 peer-reviewed papers, including many addressing the mechanisms subserving the effects of psychostimulants, hallucinogens, and entactogens.  He is the lead Series Editor for Current Topics in Behavioral Neurosciences, which has completed 43+ volumes.  He was involved intensively in the NIMH-funded MATRICS, TURNS, and CNTRICS Programs.  He has served as a receiving Editor of NeuropsychopharmacologyNeuropharmacologyPsychopharmacology, and Schizophrenia Bulletin, and as Scientific Advisor to European Union’s Innovative Medicine Initiative.  He is a Fellow of AAAS, American College of Neuropsychopharmacology (ACNP), and American Psychological Society, Past-President of the International Society for Serotonin Research and the International Behavioral Neuroscience Society, member of Scientific Council of the Brain and Behavior Research Foundation, 2011 awardee of Bleuler Prize for Research in the Schizophrenias, and the 2014 Julius Axelrod Mentorship Awardee from ACNP.  Dr. Geyer's broad experience as a researcher, grant reviewer, journal editor, and teacher lends invaluable scientific and professional expertise to PHRI, as he provides the leadership to develop a strong program in the behavioral psychopharmacology and clinical applications of psychedelic agents.

Adam L. Halberstadt, Ph.D., is Co-Director of the PHRI and an Associate Professor of Psychiatry at the University of California San Diego. He received a B.A. in Neuroscience from the University of Delaware in 1998 and a Ph.D. in Neurobiology from the University of Pittsburgh in 2006.  His graduate training focused on the organization of ascending and descending projections from serotonergic nuclei in the brainstem, work that was funded through an individual predoctoral National Research Service award (NRSA) fellowship (F31) from NIDCD.  For his postdoctoral training at the University of California San Diego (UCSD), Dr. Halberstadt received an individual postdoctoral NRSA fellowship (F32) from NIDA to study the behavioral effects of serotonergic hallucinogens. He has received independent funding from NIMH, NIDA, and from the Brain & Behavior Research Foundation.  He is a member of the International Society for Serotonin Research (ISSR, formerly known as the Serotonin Club), and an associate member of the American College of Neuropsychopharmacology (ACNP).  Dr. Halberstadt currently serves as an Associate Councilor for North America for the ISSR and is a member of the IUPHAR Serotonin Receptor Nomenclature Committee.

Cassandra Vieten, Ph.D., is an Associate Director of the PHRI, as well as Scholar-in-Residence at the Arthur C. Clarke Center for Human Imagination at the University of California, San Diego, Executive Director of the John W. Brick Foundation, and Senior Fellow at the Institute of Noetic Sciences, where she worked for 18 years in successive roles as Scientist, Director of Research, CEO, and President from 2013-2019. She is a psychologist, mind-body medicine researcher, author of numerous articles in scientific journals, and an internationally recognized keynote speaker.

Her research has focused on spirituality and health, transformative experiences and practices, and the development of mindfulness-based interventions for emotional well-being. She received her Ph.D. in clinical psychology at the California Institute of Integral Studies, and completed her research training in behavioral genetics at UCSF. She is the author of Mindful Motherhood: Practical Tools for Staying Sane During Pregnancy and Your Child’s First Year, and co-author of Living Deeply: The Art and Science of Transformation in Everyday Life, and Spiritual Competencies in Clinical Practice: Guidelines for Psychologists and Mental Health Professionals.

Her current projects focus on how mental health care be transformed so that it includes fitness/movement, nutrition, mind-body, and clients’ spiritual and religious beliefs and practices (when relevant) to foster mental and emotional fitness and well-being; what environmental and internal conditions, agents, practices, and states of consciousness stimulate imagination – in particular, the ability to see new possibilities; how cognitive, social and neuroscience along with practices from the world’s wisdom traditions can foster positive change in individuals and in our world (see Consciousness, Communication and Change program and Campaign Science for the political and activist arena), and how introducing people to awe-inspiring ideas and environments can stretch their imagination or help them see things from a new perspective, leading to self-transcendence, shifts in worldview and perspective on life, and other prosocial emotions and behaviors.

Questions? Email us at