Addictive cravings still detectable after death

A protein known as FosB in the reward centre of the brain alters in chronically ill people suffering from an addictive disorder (e.g. heroin addiction): it is genetically modified, split off and shortened. This modification under the stimulus of the drug results in the protein being more stable and therefore remaining longer in this part of the brain than in its original form – even as much as several weeks after withdrawal of the drug.  This means that a craving for this stimulus persists. This addictive craving is stored in a sort of “memory” function and, surprisingly, can still be detected after death.

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