Tegmental inhibition on isthmic neurons is mediated by the decussatio veli in amphibians.

Abstract

This in vitro study on toads (Bufo bufo gargarizans) provides the first electrophysiological evidence that electrical stimulation of the decussatio veli in the midbrain tegmentum predominantly produced inhibition on neurons extracellularly recorded from the nucleus isthmi (NI). These cells were distributed throughout the nucleus. The present study lends strong support to the suggestion that the extratectal input to NI is mainly inhibitory and gives a good explanation for the previously reported inhibition of isthmic neurons by the contralateral optic nerve stimulation (Wu and Wang, 1995a).