/ 6 June 2016

Taking fewer risks with age is biologically determined

Feedback was extracted from the results of people doing puzzles on a smartphone app – The Great Brain Experiment.
Feedback was extracted from the results of people doing puzzles on a smartphone app – The Great Brain Experiment.

Taking fewer risks as you grow older is inevitable, according to scientists who have linked a drop in dopamine levels to people becoming more risk adverse.

The study – conducted by University College London and published in the journal Current Biology – used feedback from 25 000 people to reach its conclusions. This feedback was extracted from the results of people doing puzzles on a smartphone app – The Great Brain Experiment.

It found that older people are less likely to choose risky gambles to win more points. But they are as likely as younger people to take risky gambles to avoid losing points.

The team linked this to a reduction in dopamine levels, which drop by 10% a decade in adult life. The chemical in the brain is critical in predicting which actions will lead to rewards.

Previous research has found that people choose significantly more risky gambles to win more money when they are given drugs that boost their dopamine levels.

Dr Robb Rutledge, the study’s lead author, said: “Older people were not more risk-adverse overall, and they didn’t make more mistakes than young people did. Older people were simply less attracted to big rewards and this made them less willing to take risks to try to get them.”

The app involves gambling for points: a player starts with 500 points and has to win as many points as possible in 30 different trials. These trials are broken down into those that ask people to gamble on either losing, or gaining points. Each one of these then comes with a safe option and a risky 50/50 gamble.

In the gain trials, players can either choose a guaranteed number of points, or a 50/50 chance of winning more points or gaining nothing. Here, 72% of 18- to 24-year-olds chose to gamble, while 64% of 60- to 69-year-olds also chose to gamble.

In the loss trials, players can choose to lose a fixed number of points, or take a 50/50 gamble on losing more points or losing nothing. In this, 56% of all age groups chose to gamble.

Mixed trials allow players to take zero points, or gamble with the chance of either losing or gaining points. Here 67% of all age groups chose to gamble.

The researchers said this has lots of implications for real world concerns – such as political campaigns. These tend to frame voting decisions negatively – such as saying that one choice will leave people worse off. This resonates with older people, which the study corroborated.

But the researchers said campaigns should also take an optimistic approach, where the potential for large rewards is emphasised. Given their findings, the team said this would encourage younger voters to vote a certain way.

The Great Brain Experiment can be downloaded for iPhone and Android, with the results adding to further research