Relationship between Gut Microbiota and Personality: Approach for the future

Background and Aim : A remarkable surge is seen in studies on the relationships between the gut microbiome and personality in humans during the last years. Previous works suggest that intestinal microbiota affects the gut-brain axis in addition to impacts on the digestion, immune system, body metabolism, growth and even behavior. In some recent studies, psychiatric symptoms improved by transplantation of fecal microbiota in patients with intestinal disease. The effects of gut microorganisms on neurons have largely been attributed to various neurotransmitters produced by themMethods : Articles published in the past ten years were searched on PubMed (MEDLINE) using the keywords personality, trait, gut microbial, cognitive, empathy, borderline and neuroticism.Results : Some personality traits are associated with gut microbiota, and some studies have shown that even antibiotic treatment and changes in the microbial flora can affect behaviors and certain mental states. As some studies show the role of dysbiosis, increased levels of oxidative stress and increased inflammatory activity in the pathoetiology of borderline personality disorder. Increase Lactobacillus associated with Self-judgement and decrease of inflammation with cognitive empathy. The prevalence of Lactobacillus spp was directly related to positive self-judgment but was indirectly related to lower cognitive depression and emotional empathy. Some studies have shown that personality traits are significantly associated with the diversity of gut microbiota, and high neuroticism and low conscientiousness groups are associated with high abundance of gammaproteobacteria and proteobacteria, respectively.Conclusion : Regarding the whole spectrum of our current knowledge about the influence of gut microbial diversity on personality, and considering the quite possible reverse situation, that is, the determining role of personal behaviors on foods chosen, travel, individual hygiene, social contacts etc, we think that the following strategies should be followed by the health policy makers, researchers and academic societies to create a more rational way of life in terms of gaining the most out of microorganisms: • Necessity of development of easy, cheap methods for phenotypic characterization of gut microbiome, to obtain a "microbiome fingerprint" in each individual. • Need for mass genotyping of gut (or even whole organism) microbiota in each person using methods such as ۱۶s rRNA typing or preferably by the metagenomic methods.

Keywords:

Brain , Gut , Microbiome , Personality , Psychiatry