Conditioned responses in a decorticate dog to acoustic, thermal, and tactile stimulation.

Abstract

A completely decorticate dog was prepared and tested for conditioned responses using shock as the unconditioned stimulus. Diffuse responses (movements of the fore and hind legs and the tail) were conditioned to a loud tone, a bell, a warm stimulus brought near the side of the animal''s head, neck or thorax and a tactile (wire brush) stimulus applied to the right hip. All stimuli but the tactile had to be of rather great intensity. No conditioning was obtained to visual stimulation. A differential response to a bell and a 1000-cycle tone was developed. Extinction and reestablishment of the conditioned response were demonstrated with the loud tone stimulus. Although the diffuse conditioned responses appeared about as quickly as they do in normal animals, no adaptive conditioned responses of any kind were observed in the decorticate animal.