Keywords: Risk-taking behavior, non-invasive brain stimulation, gut-brain axis, probiotics

"A gut feeling: Noninvasive brain stimulation, gut microbiota and decision-making under risk"

The majority of our daily choices include some degree of risk. This dissertation comprises a series of studies that investigate risk-taking behavior through the lens of decision neuroscience, exploring its neural processing from the brain to the gut.

The first part includes studies using transcranial alternating current stimulation (tACS) and electroencephalography (EEG) to investigate the role of frontal theta-band activity in the modulation of risk-taking behavior. Part 2 explores the specific roles of the right DLPFC (rDLPFC) and the ventromedial prefrontal cortex (VMPFC) in this type of behavior and demonstrates that both areas are involved in valuation processing and the modulation of risk-taking behavior, reinforcing evidence of a strong functional interplay (Hare et al., 2009; Schiller et al., 2014).

Finally, in part 3, the neural basis of risk-taking behavior was explored by looking beyond the central nervous system. The gut microbiota can influence various cognitive processes via the gut-brain axis (GBA). This study explores the effects of a probiotics manipulation on participants’ risk-taking behavior and intertemporal choices. The results show that probiotics led to a relative reduction in risk-taking behavior and increased likelihood of opting for delayed gratification, with reduced discount rates and lower risk proneness.

In conclusion, this dissertation provides novel insights into the neural mechanisms underlying risk-taking behavior, both within the central nervous system and including the gut-brain axis as a potential key actor.

Click here for the live stream.