This Is Your Brain on Meth: A 'Forest Fire' of
By SANDRA BLAKESLEE New
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
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."
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
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 who 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.
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.