This has been one of the unsolved puzzles of human behaviour. Researchers suggest that the recent findings could support the theory that more cautious behaviour as we age could be a result of diminished grey matter.
Brain scans of 52 volunteers aged 18 to 88 found that the volume of grey matter in one of the regions of the brain tended to be smaller in those who were more conservative in their decision-making. Also, it’s a fact that grey matter in the brain diminishes with age.
Taking fewer risks might generally be regarded as a good thing. People tend to take the most risks in adolescence, a trend which plays a major role in the high numbers of young people killed in road traffic accidents. But in older age, and in some mental disorders, people can become so risk-averse that it is counterproductive. People might take out unnecessary insurance policies, or not invest their savings out of fear of taking any risks at all.
Ifat Levy, a neuroscientist who led the research said that this could lead to new interventions — in the form of drugs or behavioural therapies — to boost people’s decision-making skills as they age or develop conditions that affect their ability to make good choices.
“It’s still very preliminary, but I do believe that in the long run this might lead to more individually tailored interventions for people,” Levy said. “If we understand the neurobiology and not just the behaviour, it might lead to more behavioural and pharmacological interventions. We know sometimes older adults make decisions that are not necessarily best for them. It can be easy to take advantage in a few cases.”
Writing in the journal Nature Communications, the scientists point out that in a little over 30 years, the number of adults in the world aged 60 and above will outnumber children for the first time in history. With that in mind, they add that understanding the mechanisms that affect decision making is “an important first step in forecasting how decisions made by an ageing population might impact political and economic processes at the global and local levels.”
Benedetto De Martino, a cognitive neuroscientist at University College London, said, “It’s not that this region is the full culprit. If I can prevent the grey matter from shrinking in an old person, it won’t stop them becoming risk-averse.”