Effects of aerobic running vs. reading rest after fear extinction on recall: Decreased prefrontal cortex activity to distinguish threat and safety cues.

Recall of extinction memory, pivotal in the treatment of anxiety-related psychiatric disorders, involves the retrieval of learned safety associations to reduce conditioned fear responses. This study examines the differential impacts of two non-pharmacological interventions, aerobic running and reading rest, both common in daily life, on fear extinction recall by measuring neural activity and self-reported risk expectation levels. Participants (n = 64) were randomly assigned to either a running group or a reading group, and underwent a three-day differential fear conditioning task. Neural activity was assessed using functional magnetic resonance imaging (fMRI), focusing particularly on the prefrontal cortex involved in fear regulation and memory processing. Findings indicate that participants in the running group showed significantly reduced dorsomedial prefrontal cortex (dmPFC) activation during fear recall while discriminating threat and safe cues, along with greater reductions in differential expectation scores (CS+ vs. CS-) from acquisition to recall phase compared to the reading rest group. These results suggest that aerobic running may facilitate fear extinction more effectively than reading rest by modulating dmPFC function. This study explores the neural mechanisms that underpin the effects of exercise on fear memory and proposes a potential method for enhancing exposure-based therapy, potentially through targeted physical activity interventions.