THE INFLUENCE OF THIOSEMICARBAZIDE ON ELECTRICAL ACTIVITY RECORDED IX THE ANTERIOR BRAIN STEM OF THE CAT

¹ Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois

Electrical activity was recorded simnultaneously from the cerebral cortex and numerous areas in the anterior brain stem of the cat. Following an intravenous convulsant dose of thiosemicarbazide there was a latent period of fifteen to thirty minutes before recorded electrical activity changed in character. The earliest altered activity invariably was recorded in the head of the caudate nucleus. Within a few minutes after the recorded changes in the caudate, synchronized spike discharge appeared in the central (periaquedyctal) grey. Subsequently spike seizure activity also appeared on the cerebral cortex and was always immediately preceded by synchronized spike discharge in the peniaqueductal grey.