Richard Ryan Darby, MD
Ryan Darby, MD, is a behavioral and cognitive neurologist whose work spans behavioral neurology, neuroimaging, cognitive-affective neuroscience, and bioethics. He is Chief of the Behavioral and Cognitive Neurology Division and Vice Chair of Research for the Department of Neurology at Vanderbilt University Medical Center (VUMC). He directs the Vanderbilt Center for Neurodegenerative Disease Research, the Frontotemporal Dementia (FTD) Center, and the Tennessee Memory Care Assessment Network (MCAN), a statewide effort to improve dementia assessment and care.
Dr. Darby’s research aims to understand the neurobiological mechanisms that give rise to abnormal behavior in neurodegenerative disease, using experimental decision-making tasks combined with neuroimaging. His central hypothesis is that complex behaviors arise from coordinated activity across brain networks rather than from any single region. To test it, he has used innovative neuroimaging methods, including lesion network mapping, coordinate-based network mapping, and atrophy network mapping. These methods have shown that lesions causing delusions, criminal behavior, and disordered free will perception fall within the same symptom-specific networks, and that seemingly inconsistent findings across neuroimaging studies, and heterogeneous patterns of atrophy in patients with the same symptoms, converge on shared networks. His work on antisocial behavior in FTD, including distinct rule-breaking and aggressive subtypes linked to ventromedial and orbitofrontal prefrontal atrophy, also informs the intersection of neuroscience with legal and forensic questions.
His current work translates these network concepts into mechanistic clinical trials and new symptomatic treatments across FTD, Lewy body disease, and Alzheimer disease. This includes his role as PI of a study of 5-HT2A receptor target engagement and functional neuroimaging changes in patients with Parkinson disease psychosis treated with pimavanserin, and his role as site PI in several ongoing FTD clinical trials.
Ryan Darby is an assistant professor of neurology and Director of the Frontotemporal dementia clinic at Vanderbilt University. He received his undergraduate degree from Princeton University in psychology and neuroscience, and his medical degree from Vanderbilt University. He trained in neurology at Massachusetts General Hospital and Brigham and Women's Hospital as part of the Partners Neurology/Harvard Medical School program. He then received the Sidney R. Baer, Jr. Research Fellowship in Clinical Neurosciences at the Beth Israel Deaconess Medical Center. He simultaneously completed a clinical fellowship in behavioral neurology and neuropsychiatry at Beth Israel Deaconess Medical Center, Massachusetts General Hospital, and McLean Psychiatric Hospital in Boston. He currently sees patients in the Frontotemporal Dementia Clinic and Dementia-related Psychosis Clinic in the Department of Neurology at Vanderbilt University Medical Center.
Clinical Interests
Dr. Darby is interested in patients with symptoms at the border zone between neurology, psychiatry, and philosophy. Both neurological and psychiatric patients can share similar symptoms, including delusions, hallucinations, criminal behavior, and disordered free will perception. This suggests that these symptoms may share a common pathway across different diseases. He uses a combination of advanced neuroimaging techniques and behavioral testing to understand the underlying neurobiology of these symptoms at the network level. His work has lent insight into how brain dysfunction can lead to delusions, hallucinations, and criminal behavior in patients with focal brain lesions and dementia. His ultimate hope is that this research will translate into new treatment targets for patients with very few therapeutic options. This includes new types of drugs, as well as the possibility of using noninvasive brain stimulation to alter specific networks in the brain.
Research Information
Dr. Darby has received numerous awards for his research, including the Stanley Cobb Award from the Boston Society for Neurology and Psychiatry, the Young Investigator Award from the American Neuropsychiatric Association, the New Investigator Award in Neuropsychiatry from the Alzheimer's Association, and the S. Weir Mitchell Award for Outstanding Early Career Investigator from the American Academy of Neurology. His work has also attracted significant media attention, including coverage in Newsweek, Scientific American, US News & World Report, Slate, Discovery Magazine, Telegraph, CBS News, and NBC News. His research is generously funded by the Sidney R. Baer, Jr Foundation, the Alzheimer's Association, the BrightFocus Foundation, and the Vanderbilt Faculty Research Scholars Award.