Cellular and Molecular Life Sciences

, Volume 70, Issue 1, pp 55–69 | Cite as

Voices from within: gut microbes and the CNS

  • Paul ForsytheEmail author
  • Wolfgang A. Kunze


Recent advances in research have greatly increased our understanding of the importance of the gut microbiota. Bacterial colonization of the intestine is critical to the normal development of many aspects of physiology such as the immune and endocrine systems. It is emerging that the influence of the gut microbiota also extends to modulation of host neural development. Furthermore, the overall balance in composition of the microbiota, together with the influence of pivotal species that induce specific responses, can modulate adult neural function, peripherally and centrally. Effects of commensal gut bacteria in adult animals include protection from the central effects of infection and inflammation as well as modulation of normal behavioral responses. There is now robust evidence that gut bacteria influence the enteric nervous system, an effect that may contribute to afferent signaling to the brain. The vagus nerve has also emerged as an important means of communicating signals from gut bacteria to the CNS. Further understanding of the mechanisms underlying microbiome–gut–brain communication will provide us with new insight into the symbiotic relationship between gut microbiota and their mammalian hosts and help us identify the potential for microbial-based therapeutic strategies to aid in the treatment of mood disorders.


Microbiota Commensal bacteria Probiotic Brain Behavior Vagus 


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Copyright information

© Springer Basel AG 2012

Authors and Affiliations

  1. 1.The Brain-Body Institute, St. Joseph’s HealthcareMcMaster UniversityHamiltonCanada
  2. 2.Firestone Institute for Respiratory HealthMcMaster UniversityHamiltonCanada
  3. 3.Department of MedicineMcMaster UniversityHamiltonCanada
  4. 4.Department of PsychiatryMcMaster UniversityHamiltonCanada

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