Gamblers mistakenly believe they can always beat the odds in a game of chance because they have developed a different pattern of brain activity to non-gamblers.
A study has identified a region of the brain - called the insula - that appears to play a critical role in supporting the distorted thinking that makes some gamblers wrongly think they have a better-than-average chance of winning.
The researchers found that when the insula is damaged as a result of brain injury, people become immune to these distortions, such as the fallacy that a run of heads means that a tails is now more likely, when in fact the 50:50 odds of heads or tails have not changed. The findings support the idea that gambling addiction has a neurological basis and could be treated with drugs that target regions of the brain, or counselling that aims to counter distortions that result in compulsive 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 Luke Clark of Cambridge University, who led the study published in the journal Proceedings of the National Academy of Sciences.