DBS cuts seizures by over 70 percent in drug-resistant epilepsy — with no cognitive decline

Deep brain stimulation (DBS), a procedure that delivers electrical impulses to specific brain regions via implanted electrodes, has been confirmed as an effective treatment option for patients with drug-resistant epilepsy—reducing seizures by more than 70 percent without causing cognitive impairment.

DBS has long been considered a critical alternative for refractory epilepsy patients who are ineligible for brain surgery. However, concerns have persisted about potential cognitive decline caused by stimulating brain regions involved in memory and cognition. The latest research findings offer important new evidence addressing these concerns.

Samsung Medical Center (SMC) announced on Thursday that a research team led by Professor Shon Young-min of the Department of Neurology performed DBS on 22 patients with intractable epilepsy (12 received thalamic DBS, 10 received hippocampal DBS). After a minimum of 18 months and an average of about three years of follow-up, cognitive function remained stable with no decline.

Professor Shon Young-min (Courtesy of SMC)

DBS identifies seizure-generating electrical signals and implants a 1-millimeter electrode to deliver stabilizing currents. For anterior temporal lobe epilepsy, the anterior thalamic nucleus is stimulated; for bilateral temporal lobe epilepsy, the hippocampus is targeted.

The research team reported that both methods significantly reduced debilitating seizures by more than 70 percent. Thalamic DBS reduced seizures by 73.05 percent, while hippocampal DBS achieved a 76.76 percent reduction. No significant decline was observed in any cognitive domain, including memory, language, attention, or executive function.

Depression and anxiety scores—another concern in epilepsy care—also did not worsen following DBS. The team emphasized that the findings confirm both the safety and therapeutic efficacy of the procedure.

Overall, the results suggest that DBS is a strong treatment option for refractory epilepsy patients, enabling personalized stimulation settings based on each patient’s epilepsy characteristics, with safety demonstrated through more than three years of follow-up.

“We confirmed that cognitive function is preserved even when stimulating core structures of memory and cognition,” Professor Shon said. “We can now recommend deep brain stimulation to patients with greater confidence.”