Piracetam inhibits Pavlovian extinction and reversal learning in a spatial task for rats

Young male rats, trained in a spatial three-choice test, showed improved task acquisition after chronic treatment with piracetam (250 mg kg(-1)). After reaching a learning criterion, one group of animals was observed during Pavlovian extinction of the task skill and another group was assigned to reversal learning. The rate of extinction was slowed down in piracetam treated specimens compared to control animals. During reversal training, a new choice had to be learned while the previously acquired choice was no longer reinforced. Acquisition of the new skill was significantly impeded by piracetam in contrast to acquisition of the first skill, which was facilitated. Also during reversal learning, the piracetam treated group persevered longer than the control group in repeating the first acquired choice at the expense of learning the new choice. It is therefore suggested, that the impediment of reversal learning was caused by inhibition of extinction. In an open-field test, the time spent exploring in motion was increased by piracetam while the velocity of locomotion was unaffected by the drug. In a novelty test, piracetam increased the rate of loss of interactions with the novel object.