Search the Health Library
Get the facts on diseases, conditions, tests and procedures.
I Want To...
Find a Doctor
Find a doctor at The Johns Hopkins Hospital, Johns Hopkins Bayview Medical Center or Johns Hopkins Community Physicians.
I Want To...
Find Research Faculty
Enter the last name, specialty or keyword for your search below.
A few days spent with a relative steered Sridevi Sarma toward her current area of research, a surgical therapy for Parkinson’s disease and other movement disorders called deep brain stimulation.
You have bachelor’s, master’s and doctoral degrees in electrical engineering. How did you become interested in studying deep brain stimulation?
SARMA: Part of it was that I have an aunt who has a rare early-onset Parkinson’s disease. Parkinson’s usually strikes people in their sixties. My aunt was diagnosed at age 29.
When I was in graduate school, I minored in cognitive science, and for a neuroscience course, I did a case study of my aunt. I videotaped her, interviewed her, did cognitive tests. I learned a lot.
What did you observe?
SARMA: She was popping 10 to 15 pills per day for various things. There was literally a pile of pills she had to take. Some medicines were for the Parkinson’s. Others were for side effects from those medications. She was taking the drug levodopa, which after a number of years can cause patients to have severe involuntary movements called dyskinesia.
At one point she was literally lying on the floor in convulsed movements. It was draining, visiting with her. And I saw what her husband went through helping to care for her. It reshaped my thinking of illness. It also got me thinking: What’s happening in the brain?
As an engineer, how did you approach that question?
SARMA: I thought: How can I use these tools that we normally apply to electrical systems and mechanical systems to this problem?
As engineers, we model the dynamics of machines such as planes, and we figure out how to control these machines by varying the input, which, in the case of a plane, would be with a device such as a motor. So I thought, why can’t we apply these same approaches to the brain? I should be able to model the electrophysiology of the brain (the healthy brain and the brain in Parkinson’s disease) and then use the model to figure out how to alter its output by adjusting the input. But instead of adjusting a motor, in this case, we would adjust the electrical input applied by through deep brain stimulation. And instead of aiming to keep a plane on a straight course, in this case the objective would be to elicit neuronal firing patterns in the brain of Parkinson’s disease patients that are the same as those you see in a healthy brain.
How is your aunt now? Might your research help her?
SARMA: Probably not, as she is already so late stage. But now she has a brain stimulation implant and she’s had a pallidotomy, a surgical procedure that has benefited many patients with Parkinson’s disease. So the quality of her life has improved.
--Interviewed by Melissa Hendricks