In a new study, University of Cambridge researchers have found that "Insula", the part of the brain that has a key role in inducing emotions, is responsible for gambling addiction.

When Insula gets damaged due to a brain injury, it disrupts thinking errors linked to gambling addiction.

Gambling errors or cognitive distortions include 'near-misses' (taking another chance to beat the odds) and 'gambler's fallacy' (expecting a tail while tossing a coin in the next round after a head in the previous one).

For the study, the researchers closely examined the brain function in patients with several brain injuries.

"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," Researcher Dr Luke Clark said in a press release.

The scientists assigned patients with injuries to the ventromedial prefrontal cortex, the amygdala, or the insula to two different gambling tasks: a slot machine game with wins and 'near-misses'; and a roulette game involving red or black predictions to invoke the gambler's fallacy.

The study also comprised of control groups that included patients with injuries to other parts of the brain and healthy participants. These groups also participated in the gambling tasks.

The scientists found that except for patients with insula damage, all the others were inclined to play on after near-misses in the slot machine and also fell victim to the gambler's fallacy in the roulette game.

"Based on these results, we believe that the insula could be hyperactive in problem gamblers, making them more susceptible to these errors of thinking. Future treatments for gambling addiction could seek to reduce this hyperactivity, either by drugs or by psychological techniques like mindfulness therapies," Clark said.

In 2007, gambling generated gross revenue of $92.27 billion in the United States. Commercial casinos created 354,000 jobs and state and local tax revenues were estimated to be $5.2 billion as of 2006, Hip Hop Republican reports.

The finding is published in the journal PNAS.