Hypothermia-induced anterograde amnesia: is memory loss attributable to impaired acquisition?

The present investigation examined whether the poor test performance observed in studies of anterograde amnesia reflects a memory deficit or is a by-product of weaker initial learning resulting from impaired sensory, motivational, or associative processes. Two experiments were performed which utilized latent extinction (Experiment 1) and delay of punishment (Experiment 2) manipulations in order to assess the nature of original learning in rats trained under either hypothermic (29 degrees C) or normothermic conditions. Results from both experiments provided evidence that hypothermia treatment administered prior to training had relatively little influence on the animal's ability to acquire a passive avoidance response. Therefore, the rapid forgetting observed in hypothermia-induced anterograde amnesia is most likely due to memory deficits rather than an artifact of poorer acquisition.