By: Hannah Heitz
A plethora of studies have shown that bacterial changes in the gut have significant effects on behavior in mice, such as decreased symptomology of anxiety and depression following a course of probiotics. Inflammation of the gastrointestinal tract in mice resulted in increased anxiety behavior. The neurochemical relationship of the gut-brain axis, particularly the GABAergic and serotonergic systems, has not found consistent findings, although more research is needed. GABA is responsible for decreasing anxiety levels at the level of neurotransmitters, while serotonin is believed to be responsible for maintaining mood. 
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