- Alcohol is known to impair an individual's ability to control their behavior.
- Impaired behavioral control is known to be a factor in accidents, anti-social acts, and binge drinking.
- Psychologists from the areas of cognitive science and neuropsychology are jointly investigating the effects of alcohol on brain activity that is associated with behavioral control.
- Findings show that specific cognitive processes, certain individual characteristics, and some environmental conditions can all influence alcohol's effects on behavioral control.
"Drinkers can sometimes display foolish, inappropriate or harmful behavior that they would not exhibit when sober," said Muriel Vogel-Sprott, professor of psychology at the University of Waterloo and first author of the paper. "This is commonly attributed to the effects of alcohol, for example, explaining away the behavior by saying 'I couldn't stop myself' or 'I didn't mean it.'" Vogel-Sprott's paper was based on research presented at a symposium during the June 2000 Research Society on Alcoholism meeting in Denver. Researchers tested the effects of a moderate dose of alcohol (approximately two or three beers) on social drinkers' performance of a task. The objective was to assess specific cognitive processes that govern behavior.
"Some of the presentations showed that alcohol could diminish cognitive control of response inhibition," said Vogel-Sprott, "and that vulnerability to this disinhibition varied among individuals. In addition, there are some personal attributes - such as impulsivity, symptoms of attention deficit disorder, and the capacity to keep in mind the relevant information needed to guide behavior - that are related to poorer inhibition under alcohol. Yet other research used event-related functional magnetic resonance imaging (MRIs or brain scans) to identify those brain areas and networks that are activated when cognitive inhibitory tasks are performed. This work showed that both successful and unsuccessful inhibition of behavior is distinguishable by different brain activity and, furthermore, these effects are altered by alcohol."
Vogel-Sprott's own research examined intentional control of behavior, assessing the degree to which conscious (intentions) and unconscious (automatic) cognitive processes influence performance. She found that a moderate dose of alcohol selectively diminished intentional control when social drinkers' behavior had no environmental consequence. However, when performance under alcohol had some 'payoff' (for example, money or verbal approval), intentional control was well retained.
"Was the behavior due to alcohol," mused Vogel-Sprott, "or was it intentional? This question is controversial, particularly in the courts, where the intentionality of an alcohol-related offence can affect the sentence. The research presented in this symposium indicates that the answer is complex. On one hand, it appears that alcohol can impair cognitive processes controlling inhibition and intentional behavior. But, on the other hand, the intensity of impairment may also depend upon the characteristics of the drinker and the consequences of behavior in the drinking situation."
Mark T. Fillmore, assistant professor psychology at the University of Kentucky, was another of the presenters during the symposium. His research examined how a drug such as alcohol can disturb a person's ability to control behavior. His findings showed that alcohol-induced impairment of inhibitory control appears to have some commonalities with Attention Deficit Hyperactivity Disorder (ADHD).
"It seems that alcohol reduces the ability to stop some actions," he said. "This is important because we all have to sometimes stop what we are doing to reflect and plan more appropriate actions. Impulsive people, including those with ADHD, do not seem to be able to do this as well as others. Accordingly, impulsiveness can lead to a host of problems in school, work, and with peer relations. My work discovered that low to moderate doses of alcohol impair the ability to stop actions much in the same way that individuals with ADHD have difficulty stopping inappropriate actions, such as throwing a punch. Of course, the effects of alcohol are short-lived, lasting only about an hour or so. But these observations suggest that alcohol can produce a temporary mental state in some individuals that resembles impulsiveness, and perhaps, ADHD-like symptoms."
Fillmore's work also found that stimulant drugs can block the impairing effects of alcohol so that the ability to stop actions while under the influence of alcohol is improved. This is similar to findings that stimulant drugs (such as Ritalin) can increase the ability to stop behaviors in individuals with ADHD.
"The fact that both ADHD and acute doses of alcohol can impair the ability to withhold inappropriate behavior," he said, "raises the possibility that people with ADHD might suffer greater impairment from alcohol than those without ADHD. The major challenge for alcohol researchers has been to figure out why some people develop problems, while others do not. So the ability to identify a pre-existing trait (such as ADHD) among some individuals that contributes to alcohol problems is a very important development."
The varied yet interconnected research presented at the symposium demonstrates how scientists using research tools from cognitive science and neuropsychology are working together to study how alcohol impairs behavioral control. Their joint findings indicate that certain individual characteristics, as well as some environmental conditions, can influence alcohol's effects on behavioral control.
"We didn't find an easy answer," said Vogel-Sprott, "but we have a better 'big picture' understanding of how alcohol impairs behavior."
Co-authors of the Alcoholism: Clinical & Experimental Research paper included: Craig Easdon of the Rotman Research Institute; and Peter Finn and Alicia Justus of Indiana University. The research was funded by the National Institute on Alcohol Abuse and Alcoholism, the Alcoholic Beverage Medical Research Foundation, and the Natural Sciences and Engineering Research Council of Canada.