Effects of ZSET845 (3,3-dibenzylimidazo[1,2-a]pyridin-2-(3H)-one), a newly synthesized cognitive enhancer, and donepezil and tacrine on the scopolamine-induced cognitive deficits in rats were examined in passive avoidance and radial-arm maze tasks. ZSET845 (0.01 mg/kg) showed a greater ameliorative effect than donepezil (0.1 mg/kg) or tacrine (1 mg/kg) in the passive avoidance task. In the radial-arm maze task, ZSET845 (0.1 mg/kg) also showed a greater effect than donepezil (10 mg/kg) or tacrine (10 mg/kg). ZSET845 induced an increase in the choline acetyltransferase (ChAT) activity in the hippocampus, suggesting that the ameliorative effects of ZSET845 are related to the increase in the ChAT activity in the hippocampus.