Posts classified under: Departments

Catherine Cahill, M.Sc., Ph.D.


Catherine M. Cahill, Ph.D. trained as an opioid neuropharmaoclogist at Dalhousie University, Canada receiving her PhD in 1996. She was recruited to the Department of Anesthesiology and Perioperative Care at University of California Irvine in 2012 from Queen’s University in Canada where she held a Canada Research Chair in Chronic Pain for 10 years. She moved to UCLA in 2017 and is now a Professor in the Department of Psychiatry & Biobehavioral Sciences and a member of the Hatos Center for Neuropharmacology at the University of California Los Angeles.

She has more than 25 years experience in research that focuses on understanding mechanisms of chronic pain and opioid analgesia, tolerance, dependence and addiction. Her research spans both basic science and human research, which focuses on how chronic pain states modulate reward circuitry and changes dopaminergic transmission responsible for motivated behavior. A large emphasis of her research focuses on understanding the processes that influence the positive and negative reinforcement and changes in mesolimbic circuitry in order to identify novel treatment strategies for opioid dependence and chronic pain.

Dr. Cahill’s research is supported by the National Institutes of Drug abuse, the National Center for Advancing Translational Sciences, the National Institute of Aging, the National Institute of Dental and Craniofacial Research, the Department of Defense and the Shirley and Stefan Hatos Foundation.

Ranmal Samarasignhe, M.D., Ph.D.


Dr. Ranmal Samarasinghe received his MD and PhD degrees from the University of Pittsburgh in 2013. He completed his residency in adult neurology at UCLA in 2017 and then completed an NIH funded post-doctoral research and clinical fellowship at UCLA from 2017-2020. During this period, Dr. Samarasinghe obtained clinical training in epilepsy and neurophysiologic intraoperative monitoring. He also performed research developing stem cell-based models of epilepsy and autism, which is the foundation of his own laboratory.

Dr. Samarasinghe’s laboratory seeks to understand the mechanisms of neural network formation and dysfunction in epilepsy and autism. His efforts are focused on 3D brain-like structures called human brain organoids that are grown in a laboratory dish and that are derived from stem cells. Brain organoids can be generated from the stem cells of individual patients and may provide unique insights into the causes of human neurological diseases such as epilepsy and autism. His laboratory is developing and utilizing multiple methodologies including whole-organoid multiphoton based calcium indicator imaging, voltage sensors, traditional extracellular recordings, high throughput genomic screens, and super-resolution synaptic imaging to interrogate the developmental trajectory of nascent neural networks in organoid models. Dr. Samarasinghe will also continue to manage patients with epilepsy and autism in his clinic and perform neurophysiologic intraoperative monitoring for surgical cases performed at UCLA and affiliated hospitals.