SINGAPORE - You enter a casino, lay down your bets, and you strike it rich. Winning triggers an immediate high in the pleasure centre in the brain.
The nucleus accumbens is part of the limbic, or emotional, centre of the brain and is one of the pleasure centres.
It responds to pleasurable stimulus from sex or recreational drugs and produces dopamine, a neurotransmitter which gives the "high" which can get people addicted to drugs, sex or gambling.
Frequent but unpredictable reinforcements, or results, make it easier for someone to get addicted to casino gambling, said Dr Nelson Lee of The Psychological Wellness Centre.
Dopamine is triggered when you win in the casino. And since the effect is almost immediate, it is more gratifying.
Dr Tommy Tan of Novena Psychiatry Clinic said: "Whenever they win, they get a lot of attention from the people around them. People look forward to that."
That pleasurable activity might become a problem when people start to crave the positive feeling.
Reverend Tan Lye Keng of One Hope Centre said he has counselled many "ordinary people" who have lost their hard-earned money in casinos.
People who spend more time and money on gambling beyond what they can afford and who become secretive about their whereabouts may have a gambling problem.
Psychiatrists agree that social gamblers (those who stop when they have lost the amount they set aside for gambling) cross the line to problem gambling when they lose control of themselves, chase their losses and resort to drastic measures such as stealing, selling drugs or becoming a runner for loansharks.
One cited the case of a woman who went to a casino with a friend last year out of curiosity. But she soon became hooked and lost $200,000. She sought help only after she lost her business.
Can problem gamblers be spotted early?
People can become problem gamblers if there is an imbalance in neurotransmitters and abnormal structures in the brain resulting in "impulsivity", or a loss of self control, said Dr Guo Song, head of the research unit, addiction medicine department at the Institute of Mental Health and consultant at the National Addictions Management Service.
Anyone who is not careful can become a problem gambler as gambling is just like any other addiction, Dr Tan said.
Doctors agree that a family history of gambling may give a person genetic and environmental cues to become a gambler.
Professor Munidasa Winslow, a psychiatrist in private practice and executive director of Promises, a mental health and addictions consulting service, found that many problem gamblers come from dysfunctional families, had gambling wins recently, or were Chinese.
Dr Tan also had a patient who chalked up huge gambling debts even after his parents - both gamblers - had previously done the same.
His most serious case was a man in his early 20s whose football bets amounted to thousands of dollars per night. He dealt in drugs to repay his debts and was eventually arrested by the Central Narcotics Bureau. Some people may be more genetically predisposed to problem gambling, although researchers still have not found the specific gene linked to it, said Dr Guo.
Studies have shown that people who gamble to lift their mood or those who have an alcohol or substance abuse problem have a higher risk of becoming problem gamblers, he added.
Then there are other factors: Peer influence, availability of gambling venues, poor social support and mental health problems such as depression and anxiety.
Prof Winslow feels that a restriction or exclusion order is not the only solution.
Families should seek help if they feel there is a problem. "There should not be a stigma to seeking help as seeking help from a mental health expert is like getting financial planning advice from a financial planner," he said.
This article was first published on March 17, 2011. Get a copy of Mind Your Body, The Straits Times or go to straitstimes.com for more stories.