Snorting students underestimate effects of cocaine

XTC is out, coke is in. A worrying trend, according to psychologist and Veni winner Lorenza Colzato. "A lot of young people think that a line of cocaine now and then does no harm, but my research has shown that the opposite is true."

Colzato discovered by chance how popular cocaine is among recreational drug users. "Two years ago, I and a group of students were looking for test subjects for a study into the cognitive effects of XTC," she explains. "Those XTC users proved difficult to find. A lot of students and other young people with whom we came into contact apparently didn’t swallow but snorted."

European figures confirm that – after cannabis – cocaine is currently the most commonly used recreational drug. Colzato is no longer surprised by this. "Cocaine has become more accessible in recent years as a result of increased supply and a lower price. Because such celebrities as Lindsay Lohan and Kate Moss are addicted, young people think it is cool to use these drugs. Not in their rooms as an addict would do, but at parties. I also hear from students who took part in my research that coke is snorted at some student associations."

Harmless? A lot of young people think it is. "They underestimate the long-term effects of recreational cocaine use," warns Colzato. She showed that sniffing 1 to 4 grams of cocaine per month over a period of at least two years damages the brain’s response mechanism, even when the user is clean. "When driving, recreational users brake 25 milliseconds later when need to stop in an emergency. That may seem like a small difference, but on a motorway it can result in an accident."

Having been awarded a Veni subsidy, Colzato can now examine whether recreational cocaine usage has further damaging effects. She has developed a neurological model that she will be putting to the test. "It is well known that cocaine works on areas of the brain which regulate the control of our cognitive functions," she explains. The same areas of the brain also regulate other mental functions, such as cognitive flexibility. "I expect that these functions will also suffer as a result of cocaine usage."

Colzato will test this expectation by using computer experiments in the lab of the Faculty of Social and Behavioural Sciences. She will, for example, measure how much time test subjects take to switch between different computer tasks; a simple test of cognitive flexibility. By comparing recreational cocaine users with non-users, Colzato can determing whether cocaine usage indeed leads to impaired cognitive flexibility.

Colzato’s model does more than these predictions. It is much more specific than earlier comparable models. "I believe that cocaine works selectively on particular areas in the front part of the brain and that it has no effect on other adjacent areas. I expect that these adjacent areas can be disturbed by other substances, such as psychopharmaceutical drugs."

Colzato will not only be testing these expectations using response time experiments. With the newest brain scanning techniques she can also take a look under the skull of recreational cocaine users. For these experiments she is working closely with the Leiden Institute for Brain and Cognition. "I am curious whether I can discover differences in brain activity between users and non-users," Colzato says. "On the basis of my model, I expect to see differences in specific areas of the front part of the brain."

Just as in her earlier research, Colzato is now also applying the most up to date channels of communication to recruit test subjects: from an advert on the digital network Hyves, to a banner on the website of the BNN programme Spuiten & Slikken. The psychologist is concerned that many of her test subjects do not realise the adverse effects of their drug use. "They think: so what if I’m 25 milliseconds slower. What difference does it make? Yet they could cause an accident on the motorway. The most worrying aspect is that in all other respects these are very normal young people. They generally have no personality or psychological disturbances."

Colzato hopes that her research will serve as a warning. The Italian Veni winner has previously worked with addicted AIDS patients. She saw the destructive effects of these drugs at close hand. Subsequently she worked as a psychotherapist, and is now a researcher. The need to help other people has remained. "If people stop snorting cocaine as a result of my research, I will have achieved my aim."

(Source: Spuiten & Slikken: University of Leiden: October 2008)