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Electrical stimulation of the globus pallidus evoked chewing, rhythmic swallowing and quickly repeated movements of the contralateral foreleg directed toward the mouth. These stimulation-induced movements were more intense in rats deprived of food and/or water than in satiated animals. The facilitatory effect of water deprivation was less intense than that of food deprivation. Double-pulse stimulation experiments indicated that the evoked oral-ingestive motor responses are due to local stimulation of pre- and postsynaptic pallidal axons rather than stimulation of the adjacent axons of passage (e.g. descending cortico-bulbar fibers from the cortical jaw motor area). These findings support the view that the globus pallidus is specifically implicated in the control of oral-ingestive behaviours, and suggest that pallidal aphagia and adipsia may be a transient motor incapability to execute highly coordinated species-specific consummatory motor activities such as eating and drinking.