The genes in question affect the role of dopamine, a chemical released in the brain that signals pleasure and motivates people to seek rewards.

London - If you can’t resist the chance to put on a bet, blame your insula.

Scientists think that when this brain area is overactive, the heart rules our head and we can’t help but chase our losses.

The Cambridge University researchers said: “Future treatments for gambling addiction could seek to reduce this hyperactivity, either by drugs or psychological techniques.”

The researchers made the link after asking people with various brain injuries and healthy people play slot machine and roulette-style computer games.

A near miss on the slot machines made the players, except those with the damaged insulas, extra-keen to try their luck again.

Similarly, all of the players, apart from those with faulty insulas, made a common mistake when playing roulette.

Dr Luke Clark from the University of Cambridge, who led the research, explained that during gambling games, people often misperceive their chances of winning due to a number of errors of thinking called cognitive distortions.

For example, “near-misses” seem to encourage further play, even though they are no different from any other loss. In a random sequence like tossing a coin, a run of one event (heads) makes people think the other outcome (tails) is due next; this is known as the “gambler’s fallacy”.

There is increasing evidence that problem gamblers are particularly prone to these erroneous beliefs.

“While neuroimaging studies can tell us a great deal about the brain’s response to complex events, it’s only by studying patients with brain injury that we can see if a brain region is actually needed to perform a given task,” he said.

The researchers gave patients with injuries to specific parts of the brain two tasks - a slot machine game that delivered wins and “near-misses” and a roulette game involving red or black predictions, to bring on the gambler’s fallacy.

All of the groups - with the exception of the patients with insula damage - reported a heightened motivation to play following near-misses in the slot machine game, and also fell prey to the gambler’s fallacy in the roulette game.

The finding, which is published in the journal Proceedings of the National Academy of Sciences (PNAS), suggests that the insula, which is involved in gut feelings and decision-making, is key to the psychology of gambling.

“Based on these results, we believe that the insula 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.” - Daily Mail