Taking drugs can literally reshape your brain. With new brain-imaging techniques, scientists are becoming able to tell just how that happens—and what happens when you stop taking the drugs. Researchers in California looked at the brains of people who had used methamphetamine but had subsequently stopped.

What the researchers wanted to know: How does the brain recover after the flow of methamphetamines stops?

What they did: The researchers used a technique called "magnetic resonance spectroscopy" to look at the subjects' brains. This technology lets them look for specific chemicals in the brain, including N-acetylaspartate (NAA), a substance which can give an idea of how much brain matter has been lost (people with Alzheimer's disease, for example, have low levels of NAA in certain regions of the brain). The researchers recruited 24 former methamphetamine users from treatment centers and matched them with 13 controls who hadn't used the drug. The former users had all been addicted to methamphetamine. Eight of them had been off the drug for one to six months; the rest had been off for one to five years.

What they found: The former methamphetamine addicts had lower levels of the compound NAA in the anterior cingulum cortex, a region of the brain involved in cognition and emotion, than the people who hadn't used the drug. However, measurements of some compounds suggested that the anterior cingulum cortex of people who had been off methamphetamine longer had recovered somewhat; for measurements of another compound, their brains weren't measurably different from the brains of the controls.

What the study means to you: Methamphetamine does indeed alter your brain, and some of that change seems to be permanent. But this research suggests that some losses can be recovered—so, yes, it is worth quitting.

Caveats: The researchers didn't look at the brains of the people who had used methamphetamine before they started using the drug, so it's possible that they had different brains to start with. Also, meth users often abuse multiple drugs, so the results may have been confused by the effects of several drugs.

Find out more: Read information about methamphetamine from the National Institute on Drug Abuse.

Check out USNews.com for an article on what methamphetamines do to the brain.

Read the article: Nordahl, T.E. et al. "Methamphetamine Users in Sustained Abstinence." Archives of General Psychiatry. April 2005, Vol. 62, pp. 444–452.

Article online: http://archpsyc.ama-assn.org