Reference entry
Gut-Brain Axis
Plain-English definitions of microbiome research vocabulary — the terms you'll see across articles, testing services, and probiotic claims.
Glossary context
Defined
in the site-wide microbiome glossary
Definition
The bidirectional communication system between the gastrointestinal tract and the central nervous system, involving neural, hormonal, and immune pathways. The microbiome plays a central role in this communication.
Related terms
Vagus Nerve
The longest cranial nerve, connecting the brainstem to the abdomen. It is the primary communication channel of the gut-brain axis, with approximately 80% of its fibres carrying signals from the gut to the brain.
Psychobiotic
A live organism (probiotic) that, when ingested in adequate amounts, produces a health benefit in patients suffering from psychiatric illness. A term coined by Dinan et al. in 2013.