Abstract
The STN is a target for deep brain stimulation (DBS) in the treatment of Parkinson's disease. DBS effects are likely to affect both axons and somata within the STN, but details of effects are not known yet. We report on experiments to study the extent of stimulation effect within the STN. Two monkeys received two chronic recording chambers each. The two chambers were directed at the same STN. One of them was used to carry out electrical stimulation of the STN with a microelectrode (using monophasic stimulation at 1/s, pulse width 50 μs, amplitude < 300 μA), and the other to simultaneously record the neuronal activity in STN with standard extracellular single-unit recording techniques. Major response of STN neurons to the stimulation was a cessation of activity, starting immediately after the stimulation and lasting for 20–70 ms. STN neurons remote from the stimulation site as well as those adjacent to the stimulation site ceased to fire. Inhibitory responses were scattered in a broad area of the STN regardless of the location of stimulation electrode in the STN. Prominent suppressive effects on the activity of STN neurons would result from the electrical stimulation of the STN. [J Physiol Sci. 2008;58 Suppl:S191]
