Disruption of state-dependent learning (memory retrieval) by emotionally-important stimuli

Abstract

State-Dependent Learning (SDL) occurs when a response learned in a particular drug stste does not transfer to another drug state. SDL was demonstrated and disrupted in a modified T-maxe escape learning task, using male hooded rats. SDL groups were trained each day in one drug state (either Librium, 40 mg/kg or sterile water) and then given non-shock test trials in both drug states. SDL Ss showed drug-dependent retention since they turned randomly in opposite-state test trials and significantly above random level (P greather than 0.02) when in the training drug state. For the Transfer Ss, 1k Hz tone was simultaneously paired with foot shock in training and continued to be sounded on every non-shock test trial. Transfer Ss turned in the training direction regardless of drug state. Drug-dependence in the SDL groups and transfer in the Transfer groups were also demonstrated in response latencies. The tones were emotional memory prompters initiating some process that mediated transfer between drug states. The theoretical importance of these results were discussed in relation to energizing and directing functions of emotions and symmetrical and asymmetrical transfer.