A MIDBRAIN MECHANISM FOR FACIO-VOCAL ACTIVITY

Abstract

Central midbrain lesions, destroying the periaqueductal grey matter and adjacent tegmentum beneath the superior colliculus, abolished or greatly reduced facio-vocal behavior in a series of cats. The maintenance of other activities in these animals and the preservation of facio-vocal behavior in other animals after control lesions elsewhere in the rostral brain stem, emphasized the specificity of the deficit. Facio-vocal responses had previously been elicited by electrical stimulation within the mesencephalic region destroyed in these expts. The two lines of evidence point to a central midbrain region for integrating facio-vocal behavior in emotional expression.