Anatomy of the vagus nerve and its systemic connections: a narrative review of the literature

IntroductionThe vagus nerve is the longest cranial nerve in the human body and plays a crucial role in various functions related to the autonomic nervous system. It is involved in modulating inflammation, pain, and appetite, which makes the study of its anatomy and systemic connections particularly relevant.ObjectiveTo conduct a narrative review of the anatomy of the vagus nerve and its interactions with other systems in the body. MethodsThis is a narrative literature review based on a systematized search conducted on PubMed, Bireme (Lilacs), and Scopus databases, between August and September 2024, as well as consultation of relevant books.ResultsOf the 3,718 studies identified, 3 were selected. The findings suggest that the anatomy of the vagus nerve facilitates its interaction with various organs and systems, enabling its participation in numerous physiological processes essential to life maintenance. Vagal stimulation has emerged as a promising adjunctive treatment for various health conditions.ConclusionThe vagus nerve is essential in regulating multiple physiological functions, integrating sensory and motor systems. Further studies on its anatomophysiology may help elucidate these complexes, yet not fully understood, processes. The literature suggests that vagal stimulation holds therapeutic potential for treating inflammatory diseases, pain conditions, and neuropsychiatric conditions. Additional research is necessary to fully explore its clinical implications and enhance treatment options for challenging conditions.