Dr. Samarasinghe

Ranmal A. Samarasinghe, M.D., Ph.D. 

Assistant Professor, Neurology


Ranmal Samarasinghe, M.D., Ph.D., is a physician who treats patients with epilepsy, a spectrum of neurological diseases that cause seizures. As a scientist, he uses brain organoids – simplified three-dimensional human brain tissue grown from stem cells – to study how neurons connect to form neural circuits and how circuit dysfunction relates to conditions like autism and epilepsy. Samarasinghe hopes that findings from his research could lead to improved care for patients and ultimately to the creation of therapies for various conditions on the epilepsy spectrum.  

Epilepsy currently impacts more than 50 million people around the world, including an estimated one-third of individuals with autism spectrum disorder. Currently available antiseizure medications can prevent seizures in roughly two-thirds of epilepsy patients, but the disease remains incurable and all patients typically require lifelong treatment regimens. In collaboration with Bennett Novitch, Samarasinghe is creating brain organoids that mimic the neural circuit abnormalities seen in the brains of patients with epilepsy to model and study how the various forms of this disease impact brain function. This work could reveal why some patients do not respond to current therapies and inform the development of new treatments and cures.

Samarasinghe has demonstrated that these organoids can produce brainwave abnormalities similar to those seen in patients with epilepsy-associated neurological diseases like Rett syndrome or epileptic encephalopathy-13, an epilepsy that primarily occurs in infants. He hopes these modeling advances could one day enable researchers to use induced pluripotent stem cells derived from a patient’s skin cells to create brain organoids that replicate their unique disease. This would allow medical researchers to examine a patient’s abnormal brain rhythms in greater detail and test a number of different therapies to find the best treatment for their condition.

Samarasinghe earned both his doctorate in neuroscience and medical degree at the University of Pittsburgh.  He completed an internal medicine internship at the University of Pittsburgh Medical Center and subsequently completed an adult neurology residency and subspecialty fellowship in clinical neurophysiology at UCLA Ronald Reagan Medical Center.


Honors & Affiliations


  • American Academy of Neurology
  • American Clinical Neurophysiology Society
  • American Epilepsy Society


Human Brain Organoids and the Promise of Stem Cells
UCLA Broad Stem Cell Research Center member Ranmal Samarasinghe, MD, PhD presents his work using brain organoids to create better models of neurological disorders. An Assistant Professor in UCLA's Neurology department, Dr. Samarasinghe splits his time between the clinic, seeing patients who have neurological conditions like epilepsy and autism, and in the lab working to create more detailed disease models using brain organoids. In this video, Dr. Samarasinghe discusses how brain organoids are becoming more sophisticated in their ability to replicate irregular brain wave patterns seen in conditions like Rett syndrome, an epilepsy primarily associated with infants. Ultimately, he hopes these stem cell-based models can be used to screen new drugs and discover new treatments for diseases like epilepsy.
The Power of Regenerative Medicine
UCLA Neurology Chair and Interim Director of the UCLA Broad Stem Cell Research Center Dr. S. Thomas Carmichael is joined by William Lowry and Dr. Ranmal Samarasinghe to discuss how stem cell research could lead to therapies for neurological conditions including stroke, dementia, epilepsy and intellectual disability disorders.
UCLA Neurology Lab Profile: The Ranmal Samarasinghe Lab
UCLA Neurology is known for its state-of-the-art research labs. Here faculty, graduate students, and postdoctoral fellows work together to develop groundbreaking research methods and treatments for a wide variety of neurological diseases. In this episode of our lab profiles, we highlight the work of Dr. Ranmal Samarasinghe, Assistant Professor in the Department of Neurology at the UCLA David Geffen School of Medicine.