Furious Seasons has alerted me to an interesting article in the Boston Globe about street dealing of the antipsychotic drug quetiapine – interesting because it reveals some of our prejudices about the neuroscience of recreational drug use.
One of the mantras of neuroscience is that drugs of abuse boost the dopamine system. This led to the somewhat bizarre headlines earlier this year that modafinil may be ‘addictive’ because it was found to increase dopamine function in the nucleus accumbens, a key part of the reward system.
The reason this was bizarre is because while there are many reports of people illicitly using the drug to avoid sleep and maintain focus, there are none about ‘modafinil addicts’. In fact, I couldn’t find a single case in the literature.
However, the ‘all drugs of abuse boost dopamine’ mantra trumped the fact that there aren’t any actual addicts to make people warn about its potential for addiction. And by people I don’t just mean the press, I mean the neuroscientists who carried out the research, including Nora Volkow, head of the US’s National Institute on Drug Abuse.
In fact, it reduces function at the same D2 dopamine receptors in exactly the same ‘reward circuits’ that are supposedly always stimulated by drugs of abuse.
In other words, it does exactly the opposite of what the received wisdom tell us, and yet, it is being widely abused to the point where people are getting gunned down over shady quetiapine deals.
As scientists one of our greatest vices is fitting the world into our theories, rather than fitting our theories to the world. For neuroscientists, this is especially tempting because society has come to the popular but false conclusion that brain-based explanations trump behavioural or psychological observations.
There is more to drug abuse and addiction than dopamine and our clich√©s about the ‘reward system’ are hampering our efforts to make sense of it all.