Microbial communities in the body could influence brain and mental states by affecting emotional behaviors and other related brain systems.Researchers conducted large-scale population-based studies of the gut microbiome and brain imaging studies trying to determine the effects of the gut microbiome and how it affects the brains responses to emotional stimuli. They are hoping to show that the gut microbiome can affect disease by altering the development of autism spectrum disorder, anxiety, depression, and chronic pain [1]. From the alternative perspective, brain and mental health states could influence microbial communities by changing gut microbial populations of those with disease. Some scientists believe that some credit should be given to the alternative hypothesis. Instead of the microbes causing the disease, the disease could be changing the microbial population in the human gut [2]. For example, a child with many ear infections may require multiple courses of antibiotics. This can promote further worsening of disease by altering the gut microbiome and causing the child to become susceptible to other diseases and infections.
- Mayer E, Knight R, Mazmanian S, Cryan J, Tillisch K. 2014. Gut Microbes and the Brain: Paradigm Shift in Neuroscience.
- Hanage W. 2014. Microbiome science needs a healthy dose of scepticism. Nature 512:247–248.
