Comparing the Short and Long-Term Effects of Acute Moderate-Intensity Exercise on Mnemonic Similarity and Emotional Memory Tasks

Abstract

Mounting research has linked acute moderate-intensity exercise with changes indiscrimination of similar events – i.e., mnemonic memory. Conversely, few studies have compared performance in tasks associated to each type of memory(mnemonic similarity and emotional) and less have evaluatedperformance several days after exercise sessions. Thirty-five undergraduate students were randomly distributed in three groups that differed in the assigned duration of the moderate-intensity exercise session.Weestablished first the moderate-intensityexercise program by calculating the VO2max 50%. Two-to-five days later, participantsengaged in the exercise condition to which they were assigned, followed by a five-minute rest period. Immediately after, all participantswere exposed to the training phase of both memory tasks. The first retrieval phase was tested 45 minutes afterencoding phase was completed. Subsequent retrieval phases were conducted 24, 48, and 168 hours post-training. Exercise of long duration in creased discrimination performance in images of low similarity. Comparison of the effects of exercise on discrimination of the three types of images that the emotional-memory task entailsshowed improved performance only for aversive and neutral images. Exercise improves discrimination of low similarity images, with better overall performance after a longer exercise session. This finding adds to previous reports that have found analogous effects using other memory tasks.It also supports the notion that acute effects due to exercise are specifically related to hippocampal functionality and its ability to separate patterns. Finally, maintenance of emotional information across time suggest a different mechanism,independent of pattern-separation processing.