A gut feeling: How your brain (and your guts) defines your choices

Recent research has shown that gut microbiota can influence the interaction between the central and the enteric nervous system via the gut-brain axis (GBA). Neural activity in brain regions linked to basic emotional as well as cognitive processes have already been shown to be affected by manipulations of the gut microbiota. Whether such gut microbiota manipulations also affects human decision making, however, remains largely unknown. Based on previous studies in animal models and indications from neuroimaging studies, we here test the effects of the gut-brain 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 prolonged and controlled intake of probiotics affects risk-taking behavior and intertemporal choices using incentivized games.
We found a significant decrease in risk-taking behavior and increase in future-oriented choices in the probiotics group, as compared to placebo. These findings provide first direct experimental evidence for the functional role 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.

Keywords: Gut-Brain, Probiotics, Risk, Intertemporal choice