THIS WEEK saw the much-awaited launch of the violent computer game Grand Theft Auto IV, accompanied by the customary dire warnings that it will turn our children into killers. As if to confirm this, there were reports of a stabbing incident in a queue to buy the game in Croydon.

But ask anyone with experience of one of these hugely popular role-playing games and they will tell you that, regardless of content, the most immediate worry is that these games are so addictive, drawing in adults as well as children for hour on hour, day on day.

The British Psychological Society recently heard evidence that increasing numbers of people are not eating or sleeping properly as a result of immersion in games. There have been reports of marriages ended, obesity and even deaths (a Korean man died of an exhaustion-related heart attack after playing for 50 hours).

Why are they so addictive? It's a question that has been consistently ignored. The reason is that they are designed to be addictive.

Unlike a finite board game, they must be conquered level after endless level. They create infinite worlds that we can explore without getting sore feet. Online networking allows us to meet people with no accountability. Unlike a self-contained feature film they allow us to become someone else, and do whatever we want to do.

In other words, they represent a freedom we never get in real life, fulfiling our instinct for uninhibited and competitive behaviour, without any constraints from society. Grand Theft Auto is a prime example of this: even fans acknowledge that part of the thrill is being able to do whatever you like when you walk up to someone, from talk to them to murder them.

What this can add up to is not a chemical addiction, but what's known as a “process addiction”, a compulsion to follow a habit that provides immediate gratification through disinhibited behaviour, releasing pleasure-inducing dopamine in the brain.

Process addictions - sex and gambling addictions are other examples - are a means of continually anaesthetising ourselves from the pressures of real life, coping by escaping into another world. It's the very nature of games like Grand Theft Auto that they do this. That means by their very nature they are compulsive.

What we stand to lose are some of the hard-fought-for pleasures of real life: a real adventure, a real relationship. There's a good argument that when it comes to computer games, we should be worried about protecting ourselves from ourselves, and not just from violence.

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