Credit: National Research University Higher School of Economics

Researchers from the Higher School of Economics have shown that by stimulating the frontal cortex, a person's financial risk appetite can be increased temporarily. Their article on the cognitive mechanisms of risky decision-making was published in eNeuro , an international peer-reviewed scientific journal published by the Society for Neuroscience.

Neuroeconomics focuses on the neurobiological foundation of . Economists, biologists and psychologists use a novel interdisciplinary approach to explain the reasons behind certain decisions and inclinations. "The majority of a person's decisions take place under conditions of uncertainty or risk. This is why we were particularly interested in uncovering the neurobiological mechanisms of risky decision-making," explains one of the study's authors, Zachary Yaple, who is also a research fellow in the Centre for Cognition & Decision Making.

To solve this problem, the researchers conducted an experimental game. Each of the 34 participants chose whether they wanted to participate in a lottery that could potentially bring a monetary profit or receive a guaranteed smaller amount. While the participants were making a decision, the researchers delivered a transcranial alternating current stimulation on the left and right frontal area of the brain. The stimulation was delivered online at 5 Hz (theta), 10 Hz (alpha), 20 Hz (beta), and 40 Hz (gamma). The results showed a robust effect of the 20 Hz stimulation over the left prefrontal area that significantly increased voluntary risky decision-making.

The researchers assume that the 20 Hz stimulation led to a change in the internal rhythm of the brain and that this may suggest a possible link between risky decision-making and , underlined by beta oscillatory activity. Beta waves come about during a state of wakefulness and impact many processes in the brain. They allow a person to concentrate, aid in rapid thinking, and help achieve a goal and work with maximum efficiency. Relatively recently, researchers discovered that beta waves are particularly enhanced in the when a person receives an unexpected reward. Previous studies suggest, that beta oscillations could synchronise (couple) structures involved in reward processing. Thus, by affecting beta activity, the researchers could make outcomes of a risky decision seem more appealing.

More information: Zachary Yaple et al, Transcranial Alternating Current Stimulation Modulates Risky Decision Making in a Frequency-Controlled Experiment, eneuro (2017). DOI: 10.1523/ENEURO.0136-17.2017

Provided by National Research University Higher School of Economics