Frequency-dependent cognitive effects of Deep Brain Stimulation in Parkinson's Disease: A Systematic Review and Meta-Analysis

The study investigated the cognitive effects of deep brain stimulation (DBS) in Parkinson's disease depending on stimulation frequency. A meta-analysis included 21 studies with 355 patients who underwent subthalamic nucleus stimulation. Results showed that lower stimulation frequencies (4-80 Hz) were associated with better verbal fluency and cognitive flexibility compared to high frequencies (≥130 Hz). The difference in verbal fluency was 0.27 and in cognitive flexibility 0.38 according to Hedges' g. A similar pattern was observed when compared to stimulation turned off. Researchers concluded that lower-frequency DBS may provide modest cognitive benefits in specific domains.