This
Is Your Brain on Meth: A '
By SANDRA BLAKESLEE
Published:
People who do not want to wait for old
age to shrink their brains and bring on memory loss now have a quicker
alternative - abuse methamphetamine for a decade or so and watch the brain
cells vanish into the night.
The first 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
The image, published in the June 30 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. "The cells are dead and
gone," Dr. Thompson said. 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 30's that had
used methamphetamine for 10 years, mostly by smoking it, and 21 controls
matched for age. On average, the addicts used an average of four grams a week and
said they had been high on 19 of the 30 days before the study began.
Methamphetamine is an addictive stimulant made in
clandestine laboratories nationwide. When taken by mouth, snorted, injected or
smoked, it produces intense pleasure by releasing the brain's reward chemical,
dopamine. With chronic use, the brains that overstimulate
dopamine and another brain chemical, serotonin, are permanently compromised.
The study held one other surprise, Dr. Thompson said:
white matter, composed of nerve fibers that connect different areas, was
severely inflamed, making the addicts' brains 10 percent larger than normal.
"This was shocking," he said. But there was one piece of good news:
the white matter was not dead. With abstinence, it might recover.