Vagal nerve stimulation
Noninvasive vagal nerve stimulation reliably reduces stress responses and shows promising but still emerging potential in the management of somatization, pending larger targeted clinical trials.
This journal club reviewed the current evidence on vagal nerve stimulation (VNS) for stress reduction and its potential application in somatization disorders. Drawing on a systematic literature review performed with Consensus AI and validated by academic review, the presentation highlighted strong evidence that both invasive and noninvasive VNS reduce sympathetic arousal, modulate the HPA axis, suppress pro-inflammatory cytokines, and restore stress-altered neural oscillations. Clinical studies in PTSD and depression show consistent benefits, while animal models support its anti-inflammatory and resilience-promoting effects.
For somatization, direct clinical trial data remain limited, but the overlap between stress, inflammation, and functional somatic syndromes suggests therapeutic potential. Key limitations include heterogeneity in stimulation protocols, small sample sizes, and lack of standardized biomarkers for response prediction. Future research should focus on large-scale clinical trials in somatic symptom populations, biomarker development, and protocol standardization. At present, VNS—particularly noninvasive approaches—shows strong promise as an adjunctive therapy for stress-related conditions and possible future application in somatization.
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