Chemical sympathectomy and avoidance learning in the rat.

Reports results of 5 experiments with male Wistar rats (N = 108). Depletion of peripheral sympathetic noradrenaline induced by administration of 6-hydroxydopamine, ip, led to significant decrements in escape and avoidance responding when the required response was difficult, but not when it was relatively easy to acquire. Results are similar to previous findings obtained with adrenal-demedullated Ss. Findings clarify the role of the sympathetic nervous system in the motivation of behavior elicited by aversive stimulation. Implications for 2-process theory and the "Kamin effect," or "learned helplessness," are discussed. (40 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)