Scientists from the University of Bern have discovered a way to find who has a risk-taking personality without ever talking to them. The study recorded people’s brainwaves while they slept and found that specific patterns in the right prefrontal cortex can predict whether someone is a risk-taker.
Everybody’s limit for risk-taking differs from one individual to the next. That’s thanks to the prefrontal cortex — an important brain area involved in decision-making, judgment, and self-control.
“The fewer slow waves an individual has over their right prefrontal cortex during deep sleep, the greater their propensity for risk. Among other functions, this region of the brain is important to control one’s own impulses,” says Daria Knoch, Professor of Social Neuroscience at the University of Bern in a university media release.
Slow waves happen during deep sleep and are a sign of good sleep quality and regeneration. While people’s slow-wave sleep eventually stabilizes as people enter restorative sleep, the pattern of slow-wave sleep is highly individual. Capturing the pattern of slow-wave sleep could, therefore, create a personalized neuronal sleep profile.
The team recruited 54 individuals who get the recommended seven to eight hours of sleep daily. The slow-wave sleep was tracked through actigraphs which track the patterns of movement during sleep.
Sleep data was then collected at each person’s house and captured using a polysomnographic system with 64 electrodes placed on their scalp while they slept. “The undisturbed measurement of the brain activity during sleep in a familiar environment and the high density of data collected by the 64 electrodes are rather rare as a constellation in sleep research. This allows the participants to sleep naturally and allows us to collect a large quantity of data,” explains doctoral student and lead author, Mirjam Studler.
People who showed less slow-wave activity over the right prefrontal cortex were associated with being more likely to take risks. The risk-taking behavior was confirmed with a computer game where participants could win actual money. The game required participants to decide how far they would drive a car while knowing that at some point a wall would appear and the car would crash. Each meter taken increased their chances of getting more money, but it also increased their risk of crashing.
“Interestingly, the sleep duration had no impact in terms of propensity for risk, at least in our study with good sleepers. Rather, it is crucial that deep sleep takes place in the ‘right’ brain regions – in this case, in the right prefrontal cortex,” explains Lorena Gianotti.
The study is published in the journal Neuroimage.