Autonomic and somatomotor effects of amygdala central N. stimulation in awake rabbits.

Low level stimulation of the amygdala central nucleus was found to produce bradycardia responses in awake rabbits. Within the central nucleus the most sensitive sites were located within the medial component. The bradycardia response was accompanied by changes in respiration, most commonly an increase in frequency and a decrease in tidal volume, as well as by pupillodilation. Somatomotor responses to central nucleus stimulation were an arrest of ongoing behavior and movements of the mouth and tongue. The pattern of responses observed following stimulation of this nucleus is similar to that observed in response to threatening stimuli and suggests a contribution for this nucleus in the integration of a species-appropriate emotional response in the rabbits.