A gut feeling: how your brain (and your gut) defines your choices

Recent research has shown that gut microbiota can influence the interactions between the central and the enteric nervous system via the gut-brain axis (GBA). Brain regions responsible for emotions as well as cognitive processes have already been showed to be affected by manipulations of the gut microbiota. Whether such a link also exists in decision making, is yet unknown. Based on previous studies in animal models and indications from neuroimaging studies, we test the effects of the gutbrain axis on decision-making under risk and intertemporal choices. In a placebo-controlled double-blinded design, with two sessions separated by 28 days, during which participants received daily doses of probiotics (or placebo), we investigated whether the intake of probiotics affects risk-taking behavior and intertemporal choices using incentivized games. We show a significant decrease in risk-taking behavior and increase in future-oriented choices after the probiotics manipulation, compared to placebo. These results show the importance of the microbiota-gut-brain axis on decision-making, creating a path for potential clinical applications and allowing for a better understanding of the underlying neural mechanisms of risk-taking behavior and intertemporal choices.