Ambivalence in Rate Using Single-Lever Skinner Boxes

Abstract

Ambivalent behavior or ambivalence in rats was observed in a single-lever Skinner box situation. The behavioral features associated with ambivalence were filmed and described, and their intensities were graded. It was found that different behavioral patterns, depending on the site of stimulation, are involved in ambivalence. Moreover, the intensity of self-stimulation and withdrawal was found to be higher in subjects implanted in posterior brain areas than in rats implanted in anterior areas, suggesting the existence of a gradient of ambivalence. At a theoretical level, it was suggested that complex mechanisms, possibly involving an autonomous ambivalent system, could be responsible for ambivalence.

Competition between lateral hypothalamus and ventromedial tegmentum in electrical self-stimulation in the rat.

“…A direct preference test was performed in our experiment by having the rats choose between LH and VMT electrical stimulation. The interest in putting into competition these two areas was based on (1) the multiple similarities on the criterion of bar-pressing rates (Bruner, 1967;Dresse, 1965Dresse, , 1967Miliaressis, 1972;Olds, 1959;Olds & Olds, 1963;Roberts, 1958;St-Laurent & Beaugrand, 1972) and (2) the differences observed concerning the regulation of food (Anand & Brobeck, 1951;Margules & Olds, 1962;Miliaressis & Cardo, 1973;Mount & Hoebel, 1967) and epileptiform activity (Bogatz et al, 1965;Herberg & Blundell, 1969).…”