Pubdate: Sat, 11 Nov 2000
Source: New Scientist (UK)
Copyright: New Scientist, RBI Limited 2000
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Page: 24
Author: Andy Coghlan

JUST CAN'T GET ENOUGH

Your Body Can Become Hooked On Blackjack, Sex ... Even Gardening

ENGLAND footballers take note: gambling is as addictive as smoking, 
drinking and taking narcotic drugs.

This controversial claim by German researchers is based on a study of 
hormone levels in men playing blackjack. The findings are important because 
many addiction researchers refuse to accept that behaviours can be 
physiologically addictive.

"Some people say you can't have addiction unless you take a substance, but 
I would argue that gambling taken to excess is an addiction," says 
psychologist Mark Griffiths, who studies behavioural addiction at 
Nottingham Trent University. "If you accept that, you then accept that sex, 
computer games, even gardening, can be addictive-it opens up the floodgates 
to everything else."

Gerhard Meyer and his colleagues at the University of Bremen recruited 10 
gamblers from a casino and asked them to play blackjack, staking their own 
money. While the gamblers played, Meyer measured changes in their heart 
rates and levels of the stress hormone cortisol in their saliva. He then 
asked them to play for points rather than money, as a "control" situation.

Both heart rates and cortisol concentrations; were markedly higher when the 
gamblers played for money (see Graph). "It's the first time someone has 
measured cortisol in gambling," says Meyer.

He concedes he has not found definitive proof that gambling is addictive. 
After all, he has yet to show that raised cortisol boosts levels of key 
chemicals like dopamine. But he says it's a further step towards this. 
Gamblers themselves report feeling surges of euphoria when they place their 
bets, he points out. "Every time they bet, there's a thrill." This echoes 
the euphoria experienced by drug takers, which results from a surge of the 
neurotransmitters dopamine and serotonin in the brain.

"It's the reward system of the body," explains Meyer. "The theory behind 
addiction is that if you consume an [addictive] substance, more dopamine is 
released than normal, and this is what happens when people consume drugs or 
alcohol. When people gamble, they say they feel this euphoria through a 
behavioural surrogate. Cortisol may contribute to such mood alterations."

Meyer even speculates that such findings might reduce the culpability of 
people who have committed crimes. If lawyers can attribute their clients' 
crimes to physiological cravings rather than acts of free will, they may 
receive lighter sentences.

Next, Meyer plans to measure blood-borne stress hormones such as 
adrenaline. The ultimate proof would come from measurements of 
neurotransmitters in the brain. But this is practically impossible in 
casinos, he says.

Andy Coghlan

More at: Biological Psychiatry (vol 48, p 948)
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