The Evocation of Calls by Diencephalic Stimulation in the Conscious Chick

Electrical stimulation of the diencephalon of conscious chicks produced a number of characteristic calls. Peeps, associated with scanning head movements, are significantly associated with a periventricular and medial diencephalic system which also yields escape, hiding or freezing. Peep interruption sites lie in the lateral hypothalamus in areas from which positive reinforcement can be obtained. Startle calls, such as can be obtained from sensory structures, also occur at some lateral sites. Parallels with mammalian work are discussed.