Impact of Cortical Input on Subthalamic Activity during Deep Brain Stimulation

Cortical afferences (e.g., primary motor cortex M1, and supplementary motor area SMA) are believed to play a role in the generation of abnormal oscillatory activity in the subthalamic nucleus (STN) in Parkinson’s disease (PD). Using a computational model, we investigate how cortical inputs impact STN activity during deep brain stimulation (DBS). When cortical input to the STN is constant, high-frequency DBS is able to suppress pathological, low-frequency STN oscillations. On the contrary, when cortical input to the STN is oscillatory, DBS capacity to suppress STN abnormal oscillations is compromised. We propose that DBS induces a functional decoupling between cortex and STN. This functional decoupling may originate from spike cancellation following antidromic activation of cortical afferences.