Distribution of Applied Electrical Current in the Cerebellum and Its Effects on Purkinje Cell Activity
Date of Award
Dissertation - Restricted
Doctor of Philosophy (PhD)
Electrical and Computer Engineering
In 1973 Cooper et al (38) applied electric currents to the surface of the cerebellum to control epileptic seizures. The cerebellum influences muscle tone and synergy. This method has been used clinically for the management of motor dysfunctions (42, 95,104). The neurophysiological mechanisms were suggested to be due to the inhibitory nature of the output of the cerebellar cortex, the Purkinje cells. Several fundamental questions remained unanswered. How is the current distributed in the cerebeIIum? Does the current have an excitatory effect on the Purkinje celIs? What levels of current are required to depolarize Purkinje celIs? Studies involving current density measurements and unit potential recordings were conducted in our Iaboratory to seek the answers. Current density measurements were made with the loaded probe technique. Measurements were carried out in a saline tank model, monkey cerebellum in vivo, and human cadaver cerebellum...