Neurophysiological modulation of the subthalamic nucleus by pallidal stimulation in Parkinson's disease.
OBJECTIVE
Current models of basal ganglia dysfunction in Parkinson's disease suggest a pivotal role of subthalamic nucleus (STN) hyperactivity. There is a direct excitatory output to the globus pallidus internus (GPi), which in turn hyperinhibits the motor thalamus and leads to a lack of cortical facilitation. The model, however, does not address the reciprocal influence of GPi on STN activity.


METHODS
Measurement of immediate changes in STN single cell activity after GPi deep brain stimulation (DBS).


RESULTS
An opposite effect of GPi DBS in the dorsal versus ventral STN was found. There was an almost exclusive reduction of firing rate in the dorsal region of the STN, whereas the cells in the ventral region exhibited facilitation similar to the recordings from the substantia nigra pars reticulata.


CONCLUSIONS
Although these findings require confirmation, they suggest that the current theories of GPi DBS action, which do not include a GPi-STN modulation, are most likely incomplete.
Sterio
D
D
Department of Neurosurgery, NYU School of Medicine, NY, USA.
Rezai
A
A
Mogilner
A
A
Zonenshayn
M
M
Gracies
J M
JM
Kathirithamby
K
K
Berić
A
A
D000368:Aged; D001931:Brain Mapping; D004292:Dominance, Cerebral / Q000502:physiology; D004558:Electric Stimulation; D004599:Electric Stimulation Therapy; D004567:Electrodes, Implanted; D005917:Globus Pallidus / Q000503:physiopathology*; D006801:Humans; D008297:Male; D009433:Neural Inhibition / Q000502:physiology; D009434:Neural Pathways / Q000503:physiopathology; D009474:Neurons / Q000502:physiology; D010300:Parkinson Disease / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D013378:Substantia Nigra / Q000503:physiopathology; D020531:Subthalamic Nucleus / Q000503:physiopathology*; D009435:Synaptic Transmission / Q000502:physiology