Trigeminal influences on entopeduncular units.

Because considerable work has implicated the basal ganglia in oral-ingestive behavior, an assessment was made of the effects of trigeminal stimuli upon entopeduncular single units. Units wre recorded extracellularly in awake, paralyzed and locally anesthetized cats. The effects of two types of sensory input were tested. Afferents from periodontal mechano-receptors involved in reflex jaw opening were stimulated via electrodes in the inferior dental nerve. Afferents from stretch receptors involved in reflex jaw closure were stimulated via electrodes in the trigeminal mesencephalic nucleus. A significant proportion of cells responded to both types of stimulation. The data were discussed in the context of a basal ganglionic role in oropharyngeal motor processes and a more general role in movement per se.