Brain-Gut Communication: Vagovagal Reflexes Interconnect the Two "Brains"

The gastrointestinal tract has its own "brain", the enteric nervous system or ENS, that executes routine housekeeping functions of digestion. The dorsal vagal complex in the CNS brainstem, however, organizes vagovagal reflexes and establishes interconnections between the entire neuroaxis of the CNS and the gut. Thus, the dorsal vagal complex links the "ENS brain" to the "CNS brain". This brain-gut connectome provides reflex adjustments that optimize digestion and assimilation of nutrients and fluid. Vagovagal circuitry also generates the plasticity and adaptability needed to coordinate among organs, to maintain homeostasis, and to react to environmental situations. Arguably, this dynamic flexibility provided by the connectome may, in some circumstances, lead to or complicate maladaptive disorders.

Keywords: dorsal vagal complex; enteric nervous system; nodose ganglia; vagal afferent; vagal efferent.

PMID: 34643086 DOI: 10.1152/ajpgi.00214.2021