of the obvious. Actually, as Gossop says, the question of availability is often treated as a secondary factor, less important than any predisposition to a so-called ‘disease’.
Gossop identifies different dimensions of availability. There’s physical availability, obviously, but also psychological availability (whether someone’s personality, background and beliefs increases their interest in using particular drugs), economic availability (whether the drugs are affordable) and social availability (whether the social context encourages use of the drugs). In the case of Vietnam, he points out, many soldiers found that all the boxes were ticked. Troops in Thailand, by contrast, could easily get hold of heroin – but their lives were not in danger, they were free to move among a friendly population and their peers were not using it. Less than one per cent of military personnel took the drug.18
Availability doesn’t offer a comprehensive explanation for addiction, but it reminds us that we cannot hope to understand why people engage in addictive activities – be it shooting up heroin in the jungle or gorging on muffins in Starbucks – unless we take account of what that activity means in its social setting.
No one who has watched The Wire, the magnificent television epic of life in drug-saturated districts of Baltimore, can seriously propose that it depicts a black population afflicted by chronic disease. The characters in the show who smoke heroin do so, basically, because they live in districts where everyone does. If I lived there, I’d be a smack addict. Since I’m an addict, perhaps that goes without saying. But I have a sneaking feeling that even my local vicar would be hooked on the stuff.
Gossop, who has advised the British government on drug policy, is unusual among addiction experts for the bluntness with which he dismisses the disease theory. He describes addiction as a ‘habit’. That may sound less scary than an irreversible disease, but it isn’t. In a society overflowing with abundance, the implications of a habit of addiction driven by availability are every bit as alarming as those of a disease that strikes only individuals with malfunctioning brains.
This isn’t to deny that some people are naturally more vulnerable to addiction than others. And we can’t ignore recent discoveries in neuroscience, which show how the brain’s natural reward systems are being hijacked by newly available substances and gadgets. In the next chapter, we’ll look at what the brain does and doesn’t tell us about addiction.
But I want to end this chapter by stressing, yet again, the inadequacies of the disease model. If the word ‘disease’ is at all useful in this context, it’s as a metaphor for addiction, not as a diagnosis. And I can think of another vivid metaphor that works just as well. Modern consumers are like soldiers drafted to Vietnam – disorientated, fearful and relentlessly tempted by fixes that promise to make reality more bearable. You don’t have to be ill to give in; just human.
WHAT THE BRAIN TELLS US (AND WHAT IT DOESN’T)
Imagine the embarrassment. You are a retired civil servant with Parkinson’s disease. You are industrious and introverted, like many sufferers from the condition. (We don’t know for sure why it often strikes people with this type of personality, but the correlation was noted as long ago as the 19th century.1) You’re a regular at your local pub, where you’re known as a modest, affable chap who orders half-pints rather than pints. Occasionally you while away 20 minutes by pushing a few coins into the slot machine, accepting your losses with a philosophical shrug.
Then something odd happens. Without warning, you develop an obsession with playing the machine. You stand in front of it from opening time until last orders, much to the bemusement of the other regulars. You know that the pub’s fruit machine is programmed to return only 80 per cent of the money you put into it, but one day you hit multiple jackpots that earn you £50. The thrill of this experience – and the possibility of it happening again – reinforces your new preoccupation. You are no longer thinking rationally.
Eventually the teasing from other patrons turns to alarm as they see you pouring away your pension. The pub landlord has ‘a quiet word’ and asks you to stop playing. You’re mortified and stop going to the pub – but, instead of finding another place to drink, you slip into your local betting shop, where the jackpots are bigger. Then a newspaper article about online gambling catches your eye and before long you are shutting yourself away in your study, steadily building up credit card bills as you accrue greater and greater losses. Your wife still doesn’t have a clue.
But your problems don’t end there. Somewhere along the line, much to your own surprise, you discover a taste for internet pornography. Under normal circumstances, porn would have no appeal – you’re 70 years old, after all. But even before you stumbled across these sites you had noticed that your sexual appetite had mysteriously reawakened.
This story sounds implausible, but something very much like it happened to several Parkinson’s patients recently. They developed gambling urges out of nowhere, and in certain cases these were accompanied by a revived sex drive. There were other permutations: patients experienced a revved-up sex drive without the gambling urges, or started binge eating. Some began shopping obsessively, perhaps combining it with other risk-taking activities. The common thread was the startling change in the behaviour of people who, until recently, had devoted most of their leisure time to tending their begonias.
But the culprit wasn’t the disease. It was the medication designed to reverse its symptoms. The medicine wasn’t supposed to produce those results, but the fact that it did so provides us with vital information about the strange, self-defeating behaviours that we call addictions.
These Parkinson’s patients had been given drugs that mimicked the action of dopamine. This is a neurotransmitter, or chemical messenger, that affects our experience of pleasure and also has the ability to map out new reward pathways in the brain – in other words, to rewire it.
That’s a trendy way of describing complex changes in the brain. This is arguably the most impenetrable subject human beings have ever tried to understand. Scientists who have devoted their careers to it admit that they have only pieced together a tiny section of the jigsaw. That’s frustrating – but bear with me, because what they have discovered has fascinating implications. Dopamine is an ancient mechanism: it’s found in lizards and every other animal along the evolutionary tree. It has been called the ‘pleasure chemical’ because it is released whenever we eat good food, enjoy sex or take pleasure-enhancing drugs.
Recently, scientists have refined their understanding of dopamine. They now think that it has more to do with desire than pleasure – or, to use the refreshingly simple terms that now loom large in scientific discussions of addiction, with wanting rather than liking.
In a series of experiments on the brains of rats, the psychologist Kent Berridge of the University of Michigan came to the conclusion that ‘wanting’ (desire) and ‘liking’ (pleasure) are separate urges controlled by different brain circuits in humans as well as animals. That is an important discovery that we need to keep at the back of our minds whenever we think about how and why we are behaving addictively.
Dopamine is involved in both brain circuits, but its main function is to stimulate wanting; liking is more affected by the opioid system, which contains endorphins, the brain’s natural morphine-like compounds.2 Of the two urges, wanting is more powerful. ‘The brain seems to be more stingy with mechanisms for pleasure than for desire,’ says Berridge.3
