Gut–Brain Axis & Functional GI Disorders

Gut–Brain Axis & Functional GI Disorders represent a rapidly evolving area of gastroenterology that focuses on the bidirectional communication between the gastrointestinal tract and the central nervous system. This complex network integrates neural pathways, hormonal signaling, immune responses, and microbial metabolites to regulate gut motility, secretion, sensation, and immune function. Disruption of this finely balanced system plays a central role in the development of functional gastrointestinal disorders, including irritable bowel syndrome, functional dyspepsia, functional constipation, and disorders of gut–brain interaction. Unlike structural GI diseases, functional GI disorders are characterized by chronic, often debilitating symptoms without identifiable organic pathology. Key pathophysiological mechanisms include visceral hypersensitivity, altered gastrointestinal motility, dysregulated stress responses, low-grade mucosal inflammation, impaired epithelial barrier function, and alterations in the gut microbiome. Psychological factors such as stress, anxiety, and depression can further amplify symptoms through central processing pathways, highlighting the importance of psychosocial influences on gut function.