A professor of psychiatry from Weill Cornell Medical College, Dr. Richard Friedman, published an article in theNew York Times (August 2010), in which he described the experience of one of his patients who had abused cocaine. In this article, Dr. Friedman describes how cocaine abuse altered his patient???s ability to derive pleasure from things in his life. The patient, like many other people that are drug abusers, liked the high he received from cocaine better than anything he ever experienced ??? even sex. In fact, this patient, again like many other drug abusers, would hardly eat or drink while on a drug binge. What was interesting in this patient???s behavior, however, was that this patient no longer experienced the ???high??? from cocaine use although he was unable to stop using the drug.
As Dr. Friedman points out, it is easy to understand, pharmacologically, how people fall into abusing drugs. These drugs hijack a ???natural reward pathway??? and results in the release of the neurotransmitter dopamine. Dopamine is thought to be central to desire and pleasure. However, over time the neurons in the brain appear to adapt and the dopamine system is altered. Other studies investigating methamphetamine abusers have noted that they have about 25 percent fewer dopamine transporters (transporters are proteins that ferry neurotransmitters in and out of neurons) in their brains than normal volunteers. This decrease in dopamine transporters was still present even after these patients were methamphetamine-free for at least 11 months.
It is unclear how long these alterations in the dopamine system may last. However, being less able to feel pleasure naturally leaves recovered adicts vulnerable to other factors corralated with relapse, such as being around people from when they were addicts.As Dr. Friedman states, his patient relapsed after bumping into a friend with whom he used to use drugs.Even though Dr. Friedman???s patient has been abstinent for some time after his relapse, he still has difficulty feeling pleasure.