Effects of exogenous stimuli and centrally acting drugs on galvanic skin responses in rats.

Effects of physical stimulus and psychic stimulus on the galvanic skin response (GSR) in rats were evaluated. A significant change in the GSR was observed after exposing the rat to the noise of hand-clapping, and introducing another rat into the cage. The latter stimulus had a much greater effect than the former. Changes in GSR were measured after various animals were introduced into the test cage. A shift in the GSR in intrusion of guinea pig or rabbit was significantly greater than that in intrusion of Wistar rat, but no difference was observed in intrusion of rat and mouse. Changes in GSR were studied by introducing another animal into the test cage containing a single rat (isolated state) or a pair of rats (grouped state). The change in the GSR in the grouped state was generally smaller than that in the isolated state, but there was no difference in the score between these states when a rabbit was introduced. When the effect of drugs on changing of GSR was investigated, we found that elevation of GSR value, as induced by exogenous stimuli, was inhibited by tranquilizers such as chlorpromazine, carpipramine and diazepam. These tranquilizers in a remarkably small dose had an apparent effect on the psychic, mutual relation in GSR test in rats.