Psychoneurogastroenterology- A Review of Current Understanding


  • Aswin Krishnan Ajit Sree Narayana Institute of Medical Sciences, Ernakulam



The existence of a gastrointestinal (GI) nervous system distinct from the CNS has been recognized for more than a century. With impressive brain-like features, the GI nervous system is increasingly being postulated to have an indispensable role in the pathophysiology of various neuropsychiatric disorders. Recent research has disproved the earlier notion of the communication between the higher brain and the GI brain being a unidirectional one. The major evolutionary event of microbial colonization of the GI tract in mammals has also contributed to the complexity of the GI-brain communication, and the GI microbiome has been hypothesized to explain the genome-complexity conundrum in humans. The role of the secretory products and the genetic components, for example Pre/Pro-biotics derived from various microbial species, are becoming the focus of intense research. Though psychoneurogastroenterology is a nascent entity, the evidences accumulated over the past decade definitely indicate an enormous potential for the exploitation of the GI-brain interactions, especially in neuropsychiatric research. This review about the developments in this field is aimed at igniting more research interest into this relatively neglected field, with the hope that it may open the door to innumerous future possibilities in neuropsychiatry.

Author Biography

Aswin Krishnan Ajit, Sree Narayana Institute of Medical Sciences, Ernakulam

Assistant Professor in Psychiatry

Department of Psychiatry


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How to Cite

Ajit, A. K. (2016). Psychoneurogastroenterology- A Review of Current Understanding. Kerala Journal of Psychiatry, 29(1), 47–52.



Review Article