Scientists discover the source of gambling addiction

Researchers at the University of Cambridge have located the area of the human brain responsible for gambling addiction.

By observing several subjects with various brain injuries (along with healthy adults), while playing online slot machines and video roulette, scientists were able to identify hyperactivity of the ‘insular cortex’ as stimulating compulsive behaviour.

This cortex became excited after ‘near misses’ (bar, bar, cherry), compelling subjects to keep plugging in their pocket change. The only players who were not moved by near-misses were those with a damaged insular cortex.

Dr Luke Clark, who led the research team, explained that hyperactivity of the insular cortex leads players to regard these ‘near-misses’ positively, although they are mathematically identical to any other loss.

Therefore, the insular cortex could well be the seat of the ‘gambler’s fallacy’.

“Based on these results, we believe that the insular could be hyperactive in problem gamblers, making them more susceptible to these errors of thinking,” said Dr Clarke.

“Future treatments for gambling addiction could seek to reduce this hyperactivity, either by drugs or by psychological techniques like mindfulness therapies.”

The gambling experience has changed over the years, mostly due to the rise of online gambling. Virtual games have many more potential outcomes than physical slot machine terminals and as such, appear more interesting to players. Not to mention the graphics and sound design that give online games a lot more depth than their real-life counterparts.

All gamblers want to win but problem gamblers have difficulty with controlling their behaviour in pursuit of a prize. Science has shown us that when a person wins, the brain releases the same substance – dopamine – as when addictive drugs are administered, albeit in much smaller amounts. The compulsive gambler’s brain chemistry is similar to that of the drug addict and this revelation has lead to the way gambling addiction is treated. Instead of a moral failing or problems with impulse control, it is now viewed as a condition with some physical basis.

The ‘near-misses’ mentioned earlier are powerful events. While winning is the most ‘rewarding’ in terms of dopamine, the near-miss triggers a similar reaction in the same area of the brain. Losing is, predictably, a frustrating event and really, a near-miss is a loss. However, the brain reacts to that particular kind of loss in a different way, becoming almost as emotionally aroused as if a win event took place.

This surge of dopamine increases the urge to play for longer, even more than winning does. Someone is more likely to stop at a win than at a near-miss event, which is highly motivating and risks players gambling more than they intended. The intensity of the dopamine response is closely related to the severity of a person’s gambling addiction, with a near-miss being perceived as very strong motivation to play again by those with diminished control over their gambling.

Genetics and gambling

A Californian study has revealed that a love of gambling is actually a trait some people are born with, coded in their DNA.

Researchers at the University of California, Berkeley discovered that, when playing a simple competitive game, particular dopamine-regulating genes influenced a person’s brain whilst they were betting.

Dopamine is a brain chemical that works as part of our mental reward and pleasure seeking system. It has been linked to motivation, addiction and lust and has even been described as the Kim Kardashian of molecules.

During the study over 200 students played a competitive computer game in which they made bets with an anonymous rival whilst researchers used MRI scans to study their brains.

Differences in how each student reacted to decision making and learning in betting were down to variations in dopamine regulating genes, meaning that a person’s fondness for gambling could be attributed to their DNA.

“This study shows that genes influence complex social behaviour, in this case strategic behaviour,” said Dr Ming Hsu, an assistant professor in UC Berkeley’s Haas School of Business, “We now have some clues about the neural mechanisms through which our genes affect behaviour.”

Originally published 08/04/14. Updated 18/04/19.