Effects of altering motivation for food in rats trained with food reinforcement to discriminate between d-amphetamine and saline injections

► Rats were trained to discriminate d-amphetamine from saline injections. ► Dose-response curves were obtained after three pre-feeding conditions. ► Pre-feeding influenced response rate and latency of the first response. ► Pre-feeding did not influence the percentage of drug-lever responses. ► Pre-feeding did not influence percentage of rats that selected the drug-lever.