A new study has found that when people engage in risky behavior, such as drunk driving or having unsafe sex, it’s probably not because their brain’s desire systems are on overdrive, but because their self-control systems are not active enough.
Researchers say this could have implications for how we treat mental illness or addiction, or how the legal system assesses the likelihood of a criminal committing another crime.
Researchers from The University of Texas at Austin, UCLA, Yale, and elsewhere analyzed data from 108 people who sat in a magnetic resonance imaging (MRI) scanner — which allows researchers to see brain activity in vivid, three-dimensional images — while playing a video game that simulates risk-taking.
Using specialized software, the researchers looked for patterns of brain activity that preceded making the choice between risky or safe behavior.
The scientists then “asked” the software to predict what other people would choose during the game based solely on their brain activity. The software accurately predicted people’s choices 71 percent of the time, the researchers reported.
“These patterns are reliable enough that not only can we predict what will happen in an additional test on the same person, but on people we haven’t seen before,” said Russ Poldrack, Ph.D., director of UT Austin’s Imaging Research Center and a professor of psychology and neuroscience.
When the researchers focused their software on smaller regions of the brain, they found that just analyzing the regions typically involved in executive functions, such as control, working memory and attention, was enough to predict a person’s future choices.
This led the researchers to conclude that when we make risky choices, it is primarily because of the failure of our control systems to stop us.
“We all have these desires, but whether we act on them is a function of control,” said Sarah Helfinstein, Ph.D., a postdoctoral researcher at UT Austin and lead author of the study, which appears in the journal Proceedings of the National Academy of Sciences.
For the study, the researchers used a video game called the Balloon Analogue Risk Task (BART). Past research has shown that the game correlates well with self-reported risk-taking, such as drug and alcohol use, smoking, gambling, driving without a seatbelt, stealing, and engaging in unprotected sex.
While playing the game, a person sees a balloon on the screen and is asked to make either a risky choice — inflate the balloon a little and earn a few cents — or a safe choice — stop the round and “cash out,” keeping whatever money was earned up to that point. Sometimes inflating the balloon causes it to burst and the player loses all the cash earned from that round.
After each successful inflation, the game continues with the chance of earning another reward or losing an increasingly large amount.
“Many risky decisions share this same structure, such as when deciding how many alcoholic beverages to drink before driving home or how much one can experiment with drugs or cigarettes before developing an addiction,” the researchers noted.
Data for the study came from the Consortium for Neuropsychiatric Phenomics at UCLA. The group recruited adults from the Los Angeles area to examine the differences in response inhibition and working memory between healthy adults and patients diagnosed with bipolar disorder, schizophrenia, or adult attention deficit hyperactivity disorder (ADHD).
“Only data collected from healthy participants was included in this study,” researchers noted.
Source: University of Texas at Austin