Effects of nicotine on the shuttlebox behavior of trained guinea pigs

The comparative effects of three doses of nicotine (0.075, 0.15 and 0.3 mg/kg) were measured on the shuttlebox behavior of highly trained guinea pigs, using 50-trial sessions and a 15 sec CS-US interval. It was found that nicotine counteracted the characteristic intra-session performance decrement seen with this species and, in addition, that the various doses of nicotine could be differentiated from each other and the control (physiological saline) in this test. These results were obtained through the measurement of response latencies and the recording of intertriai responses which, for the purposes and conditions of this and future studies of this type, were shown to be more effective parameters than the measurement of avoidance frequency alone.