``Foot-stomping'' in the Gerbil: Rewarding Brain Stimulation, Sexual Behaviour, and Foot Shock

IN our programme of research directed toward understanding brain mechanisms of motivation, we have considered that other animals, as well as the white rat, should be used to investigate the phenomenon of reward elicited by direct stimulation of the brain. While widespread use of the white rat has the advantages of reducing variability within subjects, between experiments, and among experimenters, such standardization tends to limit generality of findings. Even within the order Rodentia clear differences in the open field and visual cliff may be obtained from mammals of different families. Thus the gerbil, Meriones, from the family Cricitidae, and the white rat, Rattus, from the family Muridae, demonstrate different responses in an activity situation and in a depth perception apparatus^1-3. It seemed worthwhile, therefore, to determine whether any differences existed between these two mammals in the brain reward situation. Our brain-stimulation experiments on the gerbil have led to the observation of a unique pattern of behaviour not seen in the albino rat. Such a result has suggested new directions in the investigation of the brain reward phenomenon.