Explore Rice

4/15/2005 12:07:00 AM

Study could change treatment of alcoholism

The brain waves and task performance of alcoholism patients are strikingly similar to those of people with structural damage to the brain's frontal lobe, a study by clinical and cognitive psychologists demonstrates. Both have difficulty with problem solving, abstract thinking and various memory tasks. Such findings may be critically important for therapists who treat alcohol-dependent patients, since traditional therapy requires skills that the patients initially may not have.

--------------------------------

Psychologists at Rice University and the National Institute of Mental Health and Neurosciences in India have been able to show that the brains of alcohol dependent patients seem to be malfunctioning in ways similar to the brain malfunctions of patients who have structural damage to the frontal lobe.

"Studies have shown that alcoholics have problems with executive functions – those that have to do with such cognitive tasks as working memory and abstract thinking," says Geoffrey Potts, a cognitive neuroscientist at Rice University and co-author of "Frontal Deficits in Alcoholism: An ERP Study," published in Brain and Cognition.

"The responses we got from subjects in our study indicate that alcohol dependent patients are more similar to people with frontal lesions than patients with subcortical damage both in their brain waves and in their task performance."

Potts notes that the frontal lobe of the brain is responsible for a different set of functions than those involving the subcortical area. The frontal lobe is the most advanced part of the brain and credited with such executive functions as attention, problem solving, memory, judgment, impulse control, and regulating social behavior. Subcortical areas, on the other hand, are involved in more primitive functions such as some aspects of emotions, certain motor functions, and the regulation of thirst, hunger and body temperature.

For therapists who work with alcohol dependent patients this study has implications for the treatments they may prescribe. In some cases, therapy requires certain cognitive skills such as abstract thinking, which alcohol dependent patients initially may be incapable of performing.

"In dealing with patients who have a known deficit, you first have to identify where they are having problems in case they need special help or training to overcome those deficits," Potts says.

"When designing treatment for alcohol dependent patients, for example, it would be important to know they may have working memory deficits as our study has shown."

Mary "Reeni" George, a postdoctoral fellow in Potts' lab and the primary author, Potts, and their colleagues tested four groups of subjects using a modified version of the Petrides and Milner Number Sequencing task. All of the subjects were recruited from the National Institute of Mental Health and Neurosciences in Bangalore, India. The alcohol dependent patients had an average drinking history of six years and were detoxified before taking part in the study. The subjects with lesions in the subcortical were stroke patients and those with frontal lobe lesions were either stroke patients or had recovered from tumor resections. The control group consisted of paid adult volunteers who had no prior history of substance use or neurological disorders.

Through electro-encephalograph (EEG) recordings, the researchers measured changes in the patients' brain waves before and during the number sequencing test. The study found that the ability to recall a sequence of numbers was much lower for frontal lesion patients and the alcohol dependent group than for the subcortical lesion group and for the control group with no brain damage. Additionally, both the alcohol dependent and frontal lobe patients had similarly abnormal brainwave activity, while the subcortical patients had brain activity more like the control participants.

Trained in cognitive neuroscience with additional clinical research training, Potts is also conducting research involving another part of the frontal lobe having to do with motivation, specifically how and why impulsive individuals are particularly sensitive to immediate reward.

A Phi Beta Kappa and magna cum laude graduate from the University of Oregon, where he earned his undergraduate, master's and Ph.D. degrees, Potts conducted research at Harvard's Medical School for four years before joining Rice's psychology department in 1998.

To learn more about this research, contact Potts at gpotts@rice.edu or B.J. Almond in the Office of News and Media Relations at balmond@rice.edu .

Research @Rice, 2005