Microbial communities are capable of influencing the brain and mental states. One thing is stress on the body. Stress has been proven to lead to depression or anxiety. Scientists have discovered that this stress might actually alter the gut microbial community. Not only can external factors cause this, but also within the body such as hormonally. Neurotransmitters can cause the release of these hormones and this can alter gene expression in the brain which then causes a change in the bacterial community.
