Influence of voluntary exercise and environmental enrichment on long-term memory processes in C57BL/6J mice

Excessive fear is a hallmark of various anxiety and stress disorders, such as post-traumatic stress disorder (PTSD). Current pre-clinical research has focused on identifying behavioral and neuropharmacological methods of facilitating fear extinction in order to improve well-being of PTSD patients. The present experiment investigated the effects of voluntary exercise on fear memory and object recognition memory in male C57BL/6J mice. Results suggested that mice that exercised voluntarily exhibited significantly less fear-elicited freezing behavior during cued fear extinction trials compared to that of non-exercise control mice. Results from assessment of object memory revealed no difference in object memory retention between voluntary exercise mice and control mice. These results suggest that the beneficial effects of exercise in mice appear to be specific to the task and to the specific memory process. These results suggest that voluntary exercise may hold utility for remediation of PTSD and anxiety symptoms in humans.