INTEGRATED FACIAL PATTERNS ELICITED BY STIMULATION OF THE BRAIN STEM

Abstract

Integration of the action of muscles innervated by the seventh cranial nerve has been of interest to neurophysiologists since the beginning of the nineteenth century. Sir Charles Bell¹ described "the marvelous combination of parts by which we have breathing, voice, speech, expression, smelling, coughing, sneezing and vomiting." Various levels and centers of the nervous system have been postulated for the selection of facial movements and their correlation with other somatic and automic components of purposeful acts. Sherrington² obtained contralateral contractions of facial muscles from cortical stimulation in the chimpanzee and the gorilla which were interpreted as entering into mimetic expression. From another portion of the cortical face area, contralateral movements of the lips suggesting feeding (chewing, deglutition) were elicited. Magoun, Ranson and Fisher³ traced a pathway for rhythmic movements of the mouth and for tongue lapping from the cortex to the pons in the cat. Ectors, Brookens