Boosting your mood: How exercise and the amygdala dance together.

Area of Science:

• Neuroscience
• Psychology
• Exercise Science

Background:

• Functional heterogeneity exists within amygdala subregions.
• Exercise is known to regulate emotions and alter amygdala activation.
• The specific roles of amygdala subregions in exercise-induced mood improvement are not fully understood.

Purpose of the Study:

• To investigate the distinct roles of medial amygdala (mAmyg) and lateral amygdala (lAmyg) subregions in mood improvement after acute exercise.
• To examine the neural pathways underlying these mood changes using resting-state functional magnetic resonance imaging (rs-fMRI).

Main Methods:

• Participants (n=76, aged 18-22) were randomly assigned to an exercise or control group.
• rs-fMRI scans and mood assessments (PANAS, Abbreviated Profile of Mood States) were conducted before and after a 30-minute intervention.
• Mixed-effect models analyzed Group × Time interactions on functional connectivity (FC) seeded from mAmyg and lAmyg.

Main Results:

• Exercise-induced mood improvements correlated with significant Group × Time interaction effects on FC, predominantly in the right hemisphere.
• Enhanced right mAmyg connectivity with the orbitofrontal cortex, parietal, and cerebellar regions was linked to reduced negative affect and increased self-esteem.
• Enhanced right lAmyg connectivity with the orbitofrontal cortex and striatum was associated with reduced tension/anger and increased vigor.

Conclusions:

• Acute exercise improves mood through distinct, lateralized neural pathways involving different amygdala subregions.
• The mAmyg and lAmyg play complementary roles in emotion regulation, with right mAmyg influencing affective valence and right lAmyg regulating mood states and arousal.
• This study provides a nuanced neurobiological model for the therapeutic effects of exercise on mood.