Non-invasive brain stimulation of cerebellar and cortical targets: A systematic review and ALE meta-analysis of cognitive and connectivity outcomes in adults

BACKGROUND: Beyond motor control, the cerebellum contributes to cognition, emotion, and social functioning through distributed cerebro-cerebellar loops. Neuroimaging and lesion studies implicate these networks in executive control, affect regulation, and social cognition, with relevance for psychiatric and neurodevelopmental conditions. OBJECTIVES: We conducted a systematic review and ALE meta-analysis to determine whether non-invasive brain stimulation (NIBS) applied to cortical or cerebellar targets modulates task-related brain activity and cerebro-cerebellar connectivity, and whether such effects relate to cognitive performance. METHODS: A two-step search (December 2023; updated January 2025) across PubMed, PsycINFO, Scopus, and Web of Science identified 1130 records. Twenty sham-controlled studies met inclusion criteria. Coordinate-based ALE employed random-effects inference (cluster-forming p < 0.001; cluster-level p < 0.05; 1000 permutations). RESULTS: Cerebellar stimulation of posterior lobules (Crus I/II; lobules VI-VIII) modulated language prediction, working memory, and social sequencing, with facilitation or interference depending on task demands and timing. Cortical stimulation of prefrontal and temporoparietal regions induced downstream changes in cerebellar coupling during executive and emotion-regulation tasks, particularly in clinical cohorts. ALE analysis (11 experiments; 67 foci; N = 480) identified convergent clusters in left occipito-parietal cortex and right TPJ; the latter did not survive sensitivity analyses excluding clinical samples. CONCLUSIONS: NIBS modulates networks functionally linked to the cerebellum during cognitive tasks, with heterogeneous, protocol-dependent effects. Notably, cortical stimulation causally shifts cerebro-cerebellar connectivity, with convergent clusters in left occipito-parietal cortex and right TPJ. Greater standardization and identification of response predictors are required to advance mechanistic understanding and clinical translation.