Characterization of the spiking and bursting activity of the subthalamic nucleus in patients with Parkinson's disease

Parkinson's disease (PD) is a progressive neurodegenerative disorder that affects ≈6 million people worldwide. Deep brain stimulation (DBS) of the subthalamic nucleus (STN) reduces motor disability and improves quality of life in patients with advanced PD who have severe levodopa-induced motor complications. Precise targeting of STN regions is a key factor for effective stimulation therapy. Dorsolateral neurons respond to motor movements and receive inputs mainly from the motor cortex. On the other hand, ventral portion is more related to cognitive functions. Several studies found a correlation between clinical motor scores (e.g. levodopa-related motor improvement) and the mean firing rate and signal power in the beta band. Albeit such findings are widely accepted, they might oversimplify the role of the STN in motor control. In this study, we characterized the spiking and bursting activity of STN sub-regions using intra operative multi electrode recordings and highly accurate channel localization techniques. We described no difference between dorsolateral and ventral portion of STN. Our findings suggest that the existing functional difference between STN sub-regions possibly arises from different network connections rather than intrinsic neuronal properties.