(a) Effect of exercise during abstinence on relapse-like responding and associated gene expression changes: Following acquisition, rats were given 24-hr/day extended (ExA) access to cocaine under a discrete trial procedure for 10 days. After the last cocaine self-administration session, rats were housed without (sedentary, Sed, n=8) or with access to a running wheel (2-hr/day) during early (days 1-7; Early, n=14), late (days 8-14; Late, n=10), or throughout (days 1-14; Thru, n=8) a 14-day abstinence period. Additional rats were given access to saline and housed without access to a wheel during “abstinence” (saline, Sal, n=10). On day 15 of abstinence, rats underwent extinction/reinstatement testing, and on the morning following this 1-day test session, tissue was collected. (b) Schematic illustration of the brain regions dissected for the NAc core and the dmPFC.