The Gut–Brain–Autonomic Axis: Small Intestinal Dysbiosis, Silent Inflammation, and Cognitive Decline

Chronic cognitive decline is rarely an isolated neurological phenomenon. From the perspective of Swiss Biological Medicine, it is often the expression of systemic dysregulation involving the intestine, immune system, autonomic nervous system, mitochondrial metabolism, and inflammatory burden. In this lecture, Dr. med. Thomas Rau explores the gut–brain–autonomic axis with a particular focus on small intestinal dysbiosis, silent inflammation, and their clinical relevance in early cognitive dysfunction.

The small intestine is not only an organ of digestion and absorption; it is a central immunological and neurovegetative interface. Dysbiosis, impaired mucosal integrity, endotoxin exposure, food intolerances, and disturbed bile and pancreatic function can contribute to chronic low-grade inflammation and autonomic imbalance. Over time, these processes may influence cerebral perfusion, mitochondrial energy production, neurotransmitter regulation, vagal tone, sleep quality, and cognitive resilience.

Dr. Rau will present how Biological Medicine approaches cognitive decline not only through the brain, but through the terrain in which the brain functions. Clinical attention will be given to intestinal milieu diagnostics, inflammatory patterns, autonomic regulation, nutrition, detoxification, microbiome restoration, and immune modulation. The lecture will also highlight the role of darkfield microscopy, metabolic assessment, and individualized treatment strategies in identifying underlying regulatory deficits.

The aim is to provide physicians and health professionals with a practical, cause-oriented framework for understanding cognitive decline as part of a broader biological network. By addressing small intestinal dysbiosis and silent inflammation early, Biological Medicine may offer meaningful strategies to support neurological function, autonomic balance, and long-term health regulation.