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The Psychedelics and Health Research Initiative is a collaborative endeavor cutting across multiple divisions and departments of UC San Diego. No one university has emerged as the center for research on psychedelics as a treatment for pain—nor do most have the necessary infrastructure (clinical, research, and engineering) to develop the tools and methodology to properly advance our understanding of these tools, the states they produce, and how to leverage them for patient health.

At the Psychedelics and Health Research Initiative at UC San Diego, we are in the ideal position to be a leader in the field to catalyze both basic research and therapeutic application under one umbrella of collaborative, cross-disciplinary research.

Our team includes:

  • Mark A. Geyer (Director)

    Mark A. Geyer (Director)

    Mark A. Geyer Ph.D. is Distinguished Professor of Psychiatry and Neurosciences Emeritus at the University of California San Diego and 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 Neuropsychopharmacology, Neuropharmacology, Psychopharmacology, 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 Halberstadt (Psychopharmacology Director)

    Adam Halberstadt (Psychopharmacology Director)

    Adam L. Halberstadt, Ph.D., 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.  Dr. Halberstadt has been an Associate Professor of Psychiatry at the University of California San Diego since 2018.   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.

  • Fadel Zeidan (Neuroscience Director)

    Fadel Zeidan (Neuroscience Director)

    Fadel Zeidan, Ph.D., is the Associate Director for Research at the UCSD Center for Mindfulness and Assistant Professor of Anesthesiology at UCSD.  He and his laboratory  have discovered the neural processes supporting mindfulness meditation and mindfulness-based pain relief. Recently, he and his team have demonstrated that mindfulness meditation is mechanistically distinct from and more effective than placebo, distraction, and relaxation. His research is currently funded by the National Center for Complementary and Integrative Health and has disseminated his findings through traditional media outreach (CNN NPR Time Magazine CBS and others), Tedx  and recently personally presented his work to His Holiness, the Dalai Lama in Mongolia. In his new role at the UCSD Center for Mindfulness, Fadel will focus on expanding his research to focus on working with different patient populations and user-friendly approaches to promote the self-regulation of pain. Fadel is especially excited at examining ways to integrate mindfulness from the lab to the clinic and community. 

  • Timothy Furnish (Medical Director)

    Timothy Furnish (Medical Director)

    Timothy Furnish, MD, is Associate Clinical Professor of Anesthesiology and Pain Medicine at UC San Diego where he is director of the pain medicine fellowship program and the Inpatient Pain Service. His practice includes high-risk peri-operative pain, cancer-related pain, and chronic pain management. Dr. Furnish has a master’s degree in social work from the University of Kansas and graduated from Jefferson Medical College in Philadelphia. He completed both his anesthesia residency and pain medicine fellowship at UC San Diego. He has studied, published, and lectured on post-operative pain management, gabapentin-related risks in inpatients, intrathecal drug delivery, the use of cannabinoids for the treatment of pain, and potential analgesic mechanisms of classical psychedelics.

  • Joel Castellanos (Associate Medical Director)

    Joel Castellanos (Associate Medical Director)

    Joel Castellanos, MDis a board-certified physical medicine and rehabilitation and pain medicine physician, and serves as medical director of Inpatient Rehabilitation. Dr. Castellanos’ prime focus is improving function using an individualized approach. He is particularly interested in neuromodulation at various levels including spinal cord stimulation and peripheral nerve stimulation, interventional spine procedures, radiofrequency neurotomy, ultrasound-guided and fluoroscopically-guided procedures, and regenerative medicine such as platelet-rich plasma, stem cells, and Tenex (minimally invasive technology for treatment of chronic pain). He has specific clinical interests in pelvic pain, complex regional pain syndrome, phantom limb pain, and post-spinal cord injury pain syndromes. His research interests include altering nutrition as a means of treating chronic pain, neuromodulation for chronic painful conditions as well as the potential use of psychedelics for these conditions. An associate professor in the Department of Anesthesiology at UC San Diego School of Medicine, Dr. Castellanos instructs pain medicine fellows, as well as medical students, residents in their pain rotations. Dr. Castellanos completed his fellowship in pain medicine at UC San Diego School of Medicine. He completed residency training in physical medicine and rehabilitation at University of Michigan Medical School, where he also he completed a two-year program in healthcare administration. Dr. Castellanos earned his medical degree from University of Toledo College of Medicine in Ohio. He is board certified in physical medicine and rehabilitation and pain medicine.
  • Cassandra Vieten (Psychology Director)

    Cassandra Vieten (Psychology Director)

    Cassandra Vieten, Ph.D., is Executive Director of the John W. Brick Foundation, Scholar-in-Residence at the Arthur C. Clarke Center for Human Imagination at the University of California, San Diego, 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.

  • Albert Yu-Min Lin

    Albert Yu-Min Lin

    Albert Yu-Min Lin, Ph.D., is an award-winning scientist, technologist, explorer, and storyteller (both on state and the big screen). His work to reinvent how we explore has made headlines around the world, merging adventure with innovation. His projects range from an effort to search for the tomb of Genghis Khan in Mongolia (using satellites, crowdsourcing, drones, and ground generating radar), to expeditions remapping major sites from the deserts of Jordan to the jungles of Guatemala (with aerial and ground based Lidar), to his most recent efforts to redefine human bionic capabilities through 3D prosthetics and "flow experiments". Albert is a UC San Diego Research Scientist, a National Geographic Explorer, and a curious human. He is co-author, with Drs. Ramachandran and Furnish, and the subject of the first case study of using psilocybin to treat phantom-limb pain.

  • V.S. Ramachandran

    V.S. Ramachandran

    V.S. Ramachandran, Ph.D., is Director of the Center for Brain and Cognition and Distinguished Professor with the Psychology Department and Neurosciences Program at the University of California, San Diego, and Adjunct Professor of Biology at the Salk Institute. Ramachandran initially trained as a doctor (MBBS) at Stanley Medical College, Madras, India, and subsequently obtained a Ph.D. from Trinity College at the University of Cambridge. After that, he recieved an honorary FRCP; London (Fellow of the Royal College of Physicians) and two honorary doctorates (DSc; honorus causa). Ramachandran’s early work was on visual perception but he is best known for his experiments in behavioral neurology which, despite their apparent simplicity, have had a profound impact on the way we think about the brain. He has been called “The Marco Polo of neuroscience” by Richard Dawkins and “The modern Paul Broca” by Eric Kandel. In 2005 he was awarded the Henry Dale Medal and elected to an honorary life membership by the Royal Instituion of Great Britain, where he also gave a Friday evening discourse (joining the ranks of Michael Faraday, Thomas Huxley, Humphry Davy, and dozens of Nobel Laureates). His other honours and awards include fellowships from All Souls College, Oxford, and from Stanford University (Hilgard Visiting Professor); the Presidential Lecture Award from the American Academy of Neurology, two honorary doctorates, the annual Ramon Y Cajal award from the International Neuropsychiatry Society, and the Ariens-Kappers medal from the Royal Netherlands Academy of Sciences. In 2003 he gave the annual BBC Reith lectures and was the first physician/psychologist to give the lectures since they were begun by Bertrand Russel in 1949. In 1995 he gave the Decade of the Brain lecture at the 25th annual (Silver Jubilee) meeting of the Society for Neuroscience. In 2010 he delivered the annual Jawaharlal Nehru memorial lecture in New Delhi, India. Most recently the President of India conferred on him the second highest civilian award and honorific title in India, the Padma Bhushan. And TIME magazine named him on their list of the 100 most influential people in the world.

  • Franz X. Vollenweider

    Franz X. Vollenweider

    Franz X. Vollenweider, MD. (affiliate researcher), is currently Chief Psychiatrist and Co-Director of the Center for Psychiatric Research, Director of the Neuropsychopharmacology and Brain Imaging Unit, and Professor of Psychiatry in the School of Medicine, University of Zurich. In 1999, he founded the Heffter Research Centre at the Psychiatric University Hospital, Zürich and more recently at the Swiss Neuromatrix Foundation to support multidisciplinary studies in the mind-brain interface of pharmacological (e.g. psychedelic) and non-pharmacological (e.g. meditation) -induced altered mental states.

    Since his doctorate, Dr. Vollenweider has been interested in the foundations of altered states of consciousness as well as in psychotic and affective disorders using concepts from psychology, psychopathology, and cognitive neuroscience. His current research focuses on the neuronal correlates of the sense of self, emotion regulation, and social interaction, relevant for human well-being and for the further understanding of mental disorders related to these psychological domains.

    Dr. Vollenweider has published over 150 peer-reviewed papers and book chapters, many of which address the neurobiology of psychostimulants, psychedelics, and entactogens in humans. His research is supported by multiple grants from the Swiss National Science Foundation, the Swiss Federal Health Office, the Heffter Research Institute, USA, and by multiple AWARDS from NARSAD, USA, and the Fetzer Research Institute, USA. He has received the Achievement Award of the Swiss Society of Psychiatry (1990), the Heffter Research Institute Award (1997), the Götz Prize of the University of Zurich (2000), the British Association of Psychopharmacology Prize (2002), and multiple Awards from the European College of Neuropsychopharmacology (1999, 2003, 2010), among others.

  • Sidney Zisook

    Sidney Zisook

    Sidney Zisook, M.D., is a Distinguished Professor of Psychiatry UC San Diego. He directs the UC San Diego Healer Education, Assessment and Referral (HEAR) program, dedicated to preventing/reducing nurse and physician mental health stigma, burnout, and suicide. He serves on the Scientific Review Board and Grant Review Committee of the American Foundation for Suicide Prevention (AFSP), Scientific Advisory Board of the Depression and Bipolar Support Alliance (DBSA), Board of Directors of the American College of Psychiatry and the Board of Directors of the American Society of Clinical Pharmacology. He is the UC San Diego PI on an industry-sponsored multi-site study assessing psilocybin-assisted psychotherapy for treatment resistant depression. He has recently served as the National Co-Chair of a 35-site VA Cooperative Study on Treatment Resistant Depression, PI of a NIMH research study assessing treatment of Complicated Grief and an AFSP-supported intervention study providing grief-focused psychotherapy for individuals who have lost a loved one to suicide. He was the founding president of the San Diego Board of Directors for the AFSP and PI of the John A. Majda MD Memorial Fund dedicated to facilitating research related to de-stigmatizing depression and preventing physician suicide. Over his career, he has published extensively on the treatment of depression, suicide prevention, grief and bereavement, and psychiatric education. 

  • Erik Viirre

    Erik Viirre

    Erik Viirre, MD, Ph.D., Director of the Arthur C. Clarke Center for Human Imagination at UC San Diego, Adjunct Professor of Neurosciences, Medical Director of the Qualcomm Tricorder XPRIZE, and healthcare technology innovator developing the future of medicine and visual consciousness research. He works with people who have disorders of their acceleration and gravity senses: the vestibular system, which is crucial for balance and even more important for conscious visual experience of the world. His research has shown how the brain coordinates the eyes and his medical work focuses on two of the most common conditions that affect the brain and thinking: migraine and head injury. As a technologist, Erik has helped develop Virtual Reality technologies, such as displays that scan lasers directly into the eyes, and brain monitoring techniques, for which he has 5 patents. A professional in aviation and space, Erik is a sea and instrument rated pilot. When Chief Medical Officer of Zero G, the airline that provides weightlessness, he was the team lead on missions to take Stephen Hawking, among others, into Microgravity. Dr. Viirre has done research for the National Institutes of Health, the United States Navy’s Office of Naval Research, DARPA and NASA. Dr. Viirre received his Ph.D. in Neurophysiology in 1987 at the University of Western Ontario in London, Canada and his M.D. in 1988. He completed a Rotating Internship at St. Josephs's Medical Center in London, Canada in 1989. After his internship in London, he was a fellow at the Robarts Research Institute in functional imaging and had an eye care practice. In 1994, Dr. Viirre was a Visiting Professor in Neurology and Ophthalmology at UCLA where he did a fellowship in Medical Neurotology, the management of inner ear disorders. In 1995-99 he was a Scientist at the Human Interface Technology Lab at the University of Washington. He was a Senior Scientist in the Human Performance Department of the US Navy’s Naval Health Research Center from 2001 to 2012 and is a member of the Clinical Investigation Department at Naval Medical Center San Diego as of 2012.

  • Jon Dean, Ph.D.

    Jon Dean, Ph.D.

    Jon Dean, Ph.D., is a postdoctoral scientist in the Brain Mechanisms of Pain and Health Laboratory at UC San Diego’s Department of Anesthesiology. After obtaining his B.A. in Chemistry from Youngstown State University, Dr. Dean completed his Ph.D. in Molecular and Integrative Physiology from the University of Michigan. His previous work discovered that biosynthesis of the psychedelic N,N-dimethyltryptamine (DMT) occurs in the living rat brain and that the prefrontal cortex plays a pivotal role in regulating consciousness through cholinergic mechanisms. Eager to expand his research to human patient populations, he is now developing the skills to lead an independent research program to determine the neural mechanisms supporting the promotion of well-being and the cultivation of empathy and compassion by mindfulness meditation and psychedelics. To this extent, Dr. Dean has recently been recognized as a Sanford Fellow by the UCSD T. Denny Sanford Institute for Empathy and Compassion where he will examine the mechanisms supporting empathy promotion by psilocybin-assisted therapy.

  • Ethan Hurwitz

    Ethan Hurwitz

    Ethan Hurwitz is a PhD student in the UC San Diego Department of Psychology. Before beginning his graduate training, he worked as a research coordinator for Dr. Roland Griffiths at the Johns Hopkins Center for Psychedelic & Consciousness Research. There he worked on projects which aimed to better characterize both the phenomenology and enduring effects of pharmacologically-induced altered states of consciousness, with particular emphasis on their clinical applications. He currently works with Dr. Adena Schachner investigating social cognition through probabilistic computational models.

  • Patrick Coleman

    Patrick Coleman

    Patrick Coleman is the Managing Director for the PHRI, as well as the Assistant Director of the Arthur C. Clarke Center for Human Imagination at UC San Diego, where he oversees planning for multiple research projects and programs that illuminate the neurological, cognitive, and cultural components of imagination. Among other projects, he co-organized the Art + Empathy Lab, funded by the California Arts Council’s Research in the Arts program, which presents a comprehensive perspective of attention, arousal, empathic response, and emotional regulation in real-world encounters with art through in-gallery research using multi-modal biometric data collection, machine learning, computer vision, and psychometrically validated subjective data with partners at the San Diego Museum of Art. Prior to the Clarke Center, he managed interdisciplinary collaborations as an assistant curator at the San Diego Museum of Art, including the exhibition The Art of Music and accompanying scholarly catalogue. He received a B.A. from the University of California Irvine and an M.F.A. from Indiana University.