Effect of Acute Aerobic Exercise on Ocular Measures of Attention to Emotionally Expressive Faces.

Background: Mechanisms underlying exercise-induced mood enhancement are not well understood, but it is plausible that adaptive changes in attention to emotional stimuli underlie this effect. Thus, this study examined the effects of acute aerobic exercise on eye-tracking metrics while participants viewed emotionally expressive faces.

Methods: Thirty-four adults (18 women) aged 21.1 ± 1.4 years completed two counterbalanced 30-min conditions: vigorous running or seated rest. Eye tracking occurred pre- and 20-min post-condition. Participants viewed positive (n = 15), negative (n = 15), and neutral (n = 15) emotional facial expressions from the NimStim repository. Fixation duration, longest fixation, number of fixations, and scan path length were analyzed using repeated measures ANOVAs.

Results: Exercise improved mood, but had no effect on the dependent measures (all 3-way interactions p > 0.66). However, a main effect of emotionally expressive content for fixation duration (p = 0.04, η = 0.10) and a marginally significant effect for longest fixation (p = 0.06, ηp2 = 0.09) were detected, such that fixation duration and longest fixation were greatest for faces expressing positive emotions.

Conclusion: These preliminary findings indicated that acute exercise did not alter the processing of expressive faces as indexed by eye-tracking metrics of attention. However, eye tracking effectively detected processing patterns indicative of a pleasure bias while viewing emotional facial expressions.