Exercise Modulates Working Memory-Related Brain Activation Through Bidirectional Neural Mechanisms: An ALE Meta-Analysis of Longitudinal and Cross-Sectional fMRI Studies.

BACKGROUND: Physical exercise improves working memory (WM) across the lifespan, yet the neural mechanisms underlying this benefit remain incompletely understood, and it is unclear whether intervention-induced neuroplastic changes and long-term exercise-related differences converge on common neural circuits. METHODS: We systematically searched PubMed, Web of Science, PsycINFO, and CNKI through June 2026 and included 11 task-based fMRI studies (6 longitudinal interventions and 5 cross-sectional comparisons; 403 participants) reporting whole-brain activation coordinates. Activation likelihood estimation (ALE) meta-analyses were performed separately for activation increases and decreases within each design. RESULTS: Longitudinal studies revealed exercise-induced activation increases in the bilateral cerebellum (posterior lobe, cerebellar tonsil) and decreases in the right thalamus. Cross-sectional studies revealed greater activation in the left middle temporal gyrus (BA 21) and reduced activation in the right cingulate gyrus (BA 24) and left caudate body among long-term exercisers relative to controls. Critically, the two designs yielded spatially non-overlapping patterns. CONCLUSIONS: These findings support a dual-mechanism model in which exercise strengthens task-positive network engagement while optimizing the suppression of task-irrelevant processing. They further suggest that exercise shapes working memory circuitry across distinct, timescale-dependent neural circuits.