Behavioural Effects of Electrical Stimulation in the Forebrain of the Pigeon Ii. Protective Behaviour

Abstract

AbstractResponses that showed a very good conformity to the normal defence and escape behaviour have been released by means of electrical stimulation at di- and telencephalic structures in the forebrain in unanaesthetized, freely moving pigeons (Columba livia). The defense response consisted of the characteristic threat posture of the species with crouching, ruffling of the feathers, wing erection and the growling vocalisation. The response could be very intense with defensive attacks, either in empty space or towards a threatening object. The attacks were accompanied by a short and hard call. The escape response was shown either by flying or running away. The defence and escape responses were obtained from a linked substratum extending from the hypothalamus and the diencephalic paraventricular gray via the area ventralis and the posterior parts of the cerebral peduncles up into the paleo- and archistriatum. The defence reactions were released from more medial sites compared to the escape reactions. The spatial arrangement of the active area within the forebrain shows similarities with the neural projection of the same category of behaviour in mammals. Combined data from this and a previous investigation show that a field involved in the coordination of an "agonistic" behaviour complex including aggressive and defensive threat and escape can be traced in the di- and telencephalon of the pigeon. The results produce further evidence that functionally linked actions at a high level also have a linked central representation.