Modeling parkinsonian circuitry and the DBS electrode. II. Evaluation of a computer simulation model of the basal ganglia with and without subthalamic nucleus stimulation

Treatment with deep brain stimulation (DBS) for Parkinson's disease (PD) has become routine over the past decade, particularly using the subthalamic nucleus (STN) as a target and utilizing microelectrode recordings to ensure accurate placement of the stimulating electrodes. The clinical changes seen with DBS in the STN for PD are consistently beneficial, but there continues to be only marginal understanding of the mechanisms by which DBS achieves these results. Using an analytical model of the typical DBS 4-contact electrode and software developed to simulate individual neurons and neural circuitry of the basal ganglia we compare the results of the model to those of data obtained during DBS surgery of the STN. Firing rate, interspike intervals and regularity analyses were performed on the simulated data and compared to results in the literature.