Acute stress, but not corticosterone, facilitates acquisition of paired associates learning in rats using touchscreen-equipped operant conditioning chambers.
Acute stress influences learning and memory in humans and rodents, enhancing performance in some tasks while impairing it in others. Typically, subjects preferentially employ striatal-mediated stimulus-response strategies in spatial memory tasks following stress, making use of fewer hippocampal-based strategies which may be more cognitively demanding. Previous research demonstrated that the acquisition of rodent paired associates learning (PAL) relies primarily on the striatum, while task performance after extensive training is impaired by hippocampal disruption. Therefore, we sought to explore whether the acquisition of PAL, an operant conditioning task involving spatial stimuli, could be enhanced by acute stress. Male Long-Evans rats were trained to a predefined criterion in PAL and then subjected to either a single session of restraint stress (30 min) or injection of corticosterone (CORT; 3 mg/kg). Subsequent task performance was monitored for one week. We found that rats subjected to restraint stress, but not those rats injected with CORT, performed with higher accuracy and efficiency, when compared to untreated controls. These results suggest that while acute stress enhances the acquisition of PAL, CORT alone does not. This dissociation may be due to differences between these treatments and their ability to produce sufficient catecholamine release in the amygdala, a requirement for stress effects on memory.
['Roebuck|Andrew J|AJ|', 'Liu|Max C|MC|', 'Lins|Brittney R|BR|', 'Scott|Gavin A|GA|', 'Howland|John G|JG|']
D000818:Animals D001245:Association Learning D003216:Conditioning, Operant D003342:Corpus Striatum D003345:Corticosterone D006624:Hippocampus D007858:Learning D008297:Male D008568:Memory D010153:Paired-Associate Learning D051381:Rats D020318:Rats, Long-Evans D040701:Stress Disorders, Traumatic, Acute
Strategy Striatum Restraint stress Glucocorticoid Hippocampus