You don't see this every day:
Jake at Pure Pedantry draws due attention to an incredible case report in the American Journal of Psychiatry showing that a lesion in a patient's brain cured the patient's drug addiction, apparently by knocking out the reward circuit that made the addiction pleasurable. (It also made the man badly depressed.)
A stroke that destroyed parts of a drug addict's globus pallidus (pale areas) left him depressed but ended his addiction. Neither drugs nor (alas) wine gave him pleasure any longer.
The article, unfortunately, is pay-per-view, but Jake's summary is compelling on its own. To whit:
A 34-year old long-time drug-user is taken to the ER after he starts acting freaky at a party. He has a bunch of methadone (an opiate like heroin) with him that he downs on the way in to avoid detection. He proceeds to OD.
There are areas of the brain called watershed regions. These are areas in the brain where the blood supply of the major arteries is at its sparsest -- at the overlapping edges of two arteries. When you overdose, you sometimes have strokes in these regions....
This gets us to the really interesting part. When the guy comes to, he has something called anhedonia. Anhedonia is one of the symptoms of depression. It is the inability to feel joy. More interestingly, he ALSO has lost his drug addiction.
After this overdose, Mr. A became acutely depressed .. [with] anhedonia, low energy, difficulties concentrating and remembering, feelings of hopelessness and guilt, poor self-esteem, social isolation, increased sleep, and a 20-lb weight gain over the ensuing year. He reported the disappearance of drug cravings and remained abstinent from all recreational drugs other than an occasional glass of wine with dinner. He reported that he no longer experienced pleasure from drinking alcohol. Four serial urine toxicology screens were negative over 6 months.
I thought I would point out this article because it is a very compelling case showing the parallels between lab science and medicine. Neurology is unfortunately often a science where you need cases like this to prove that we are not totally off base with how we think the brain works.
Quite incredible, and a delicious case study.