Discovery may help treat drug addicts
Researchers at the Pontifical Catholic University in Santiago say they identified a region of the brain, the insular cortex, that plays an important role in drug craving.
Tests on amphetamine-addicted laboratory rats showed that when the insular cortex was deactivated by injecting a drug that halted brain cell activity, the rats showed no signs of addiction.
When the insular cortex was reactivated, the rats again showed signs of craving amphetamines, according to the research to be published in Friday's edition of the journal Science.
"(This) indicates to us that this region of the brain processes information about the physiological states of the body and may guide behavior," said Fernando Torrealba, one of the researchers.
In a second experiment, Torrealba's team injected rats with lithium, a drug used to treat mental illness that has side effects including malaise and intestinal pain.
When the insular cortex was switched off, the rats showed no sign of malaise or pain. When it was switched on again, the rats lay on their bellies, showing signs of discomfort and sluggishness.
The scientists said there was still much to learn about the insular cortex and they did not know how people would respond if the cortex were deactivated, especially for a long period of time. The experiments on the rats lasted only about 20 minutes.
"One of the problems of course is that if the cortex processes information from the body, what happens to that information when we deactivate it long-term? Do we lose other desires? That's what we need to investigate now," Torrealba said at a news conference in Santiago.
© Reuters2007All rights reserved