Addicts Really Can't Quit
Study shows addiction may be a brain disorder
TUESDAY, July 17, 2001 (HealthDayNews) -- Certainly no one would choose to become a drug addict, but some people may lack the ability to realize that if they keep taking drugs, that's exactly what will happen, a new study finds.
Addiction may be a decision-making disorder, say researchers from the University of Iowa. And addicts may not be able to make the right choice because the part of their brain known as the ventromedial prefrontal cortex doesn't work properly.
"True addicts continue to use drugs in the face of rising consequences," says study author Dr. Antoine Bechara, assistant professor of neurology at the University of Iowa. "If the prefrontal cortex doesn't work properly, people lack the brakes [to prevent dangerous behavior]."
Bechara and his colleagues compared 41 addicts to 40 normal people and five people who had damaged prefrontal cortexes.
Damage to the prefrontal cortex results in what Bechara calls a "myopia for the future" in which people act for immediate rewards and are oblivious to the long-range consequences of their behavior. For example, a diabetic with damage to his prefrontal cortex might eat cheesecake every day because the reward from the food is immediate, and he can't grasp the future health consequences.
Each person in the study was asked to complete the Iowa Gambling Task, a test designed to assess decision-making skills.
Sixty-one percent of the addicts scored as poorly as the patients with prefrontal cortex damage. Only 32.5 percent of the control subjects scored low. The addict group performed worse overall than the control group did.
The researchers looked at the age, education, employment history, psychological status, IQ scores and other factors to find out why the addicts performed so poorly. The only factor consistently associated with poor performance for the addicts was the inability to hold a job. Staying employed was something the prefrontal cortex group had trouble doing as well.
Bechara says other studies that used PET scans to look at the brain have found damage to the prefrontal cortex in addicts. He says the damage probably starts as a developmental problem, which likely has a genetic basis. Then, taking drugs, especially those that are known to be toxic to the brain, can cause further damage.
"It's the chicken-and-the-egg question," says Dr. Petros Levounis, associate director of training at the Division of Alcohol and Drug Abuse at New York University Medical Center/Bellevue, in New York City. "Is it the drugs that are toxic somehow, and they damage those [parts of the brain], or is it those [parts of the brain] are damaged to begin with?"
Bechara says people need to realize that addiction may be a disease of the brain, just like Alzheimer's disease or Attention Deficit Disorder.
"People have no problem accepting memory and attention disorders, but they refuse to believe that you could have a decision-making disorder that would cause you to have no control over your own will," he says.
Not everyone with damage to the prefrontal cortex will become an addict, but Bechara says they are more susceptible if they start using drugs or alcohol. He suggests that the Iowa Gambling Task might be used to determine who is most at risk for addiction to drugs or alcohol.
Results of the study appeared in a recent issue of the journal Neuropsychologia.
What To Do
Levounis says cognitive psychotherapy probably would help patients with decision-making problems.
To read more about drug abuse in America, go to the U.S. Drug Enforcement Agency.
The U.S. Department of Education offer this booklet with ideas to keep kids off drugs.