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A high-resolution M.R.I. study of methamphetamine addicts shows "a forest fire of brain damage," said Dr. Paul Thompson, an expert on brain mapping at the University of California, Los Angeles. "We expected some brain changes but didn't expect so much tissue to be destroyed."
This image, published in the June 30, 2004, issue of The Journal of Neuroscience, shows the brain's surface and deeper limbic system. Red areas show the greatest tissue loss. The limbic region, involved in drug craving, reward, mood, and emotion, lost 11 percent of its tissue. Addicts were depressed, anxious and unable to concentrate. The brain's center for making new memories, the hippocampus, lost 8 percent of its tissue, comparable to the brain deficits in early Alzheimer's. The methamphetamine addicts fared significantly worse on memory tests than healthy people the same age.
The study examined 22 people in their 30s who had used methamphetamine for 10 years, mostly by smoking it, and 21 controls matched for age.
Some recent research indicates that the brain will heal itself over time, at least to some extent.
http://www.amphetamines.com/braindamage.html