Using computed tomography (CT) and magnetic resonance imaging (MRI), researchers are finding direct effects of chronic drinking on the brain and liver, according to a recent National Institute on Alcohol Abuse and Alcoholism Alcohol Alert.
Imaging studies have revealed a consistent association between heavy drinking and physical brain damage, even in the absence of other usual symptoms of severe alcoholism -- chronic liver disease or alcohol-induced dementia.
Brain Shrinkage and Alcoholic BehaviorThe shrinkage observed seems to be more extensive in the cortex of the frontal lobe, which is believed to be the seat of higher intellectual functions. This shrinkage generally increases with age, at least in men.
Repeated imaging of a group of alcoholics who continued drinking over a 5-year period revealed progressive brain shrinkage that significantly exceeded normal age-related shrinkage. The rate of frontal cortex shrinkage correlates closely with the amount of alcohol consumed.
But this shrinkage has also been observed in deeper brain regions, including brain structures associated with memory, as well as in the cerebellum, which helps regulate coordination and balance.
Reversing the EffectsA key goal of imaging in alcoholism research is to detect changes in specific brain regions that can be correlated with alcohol-related behaviors. Imaging of the cerebellum has linked both shrinkage and decreased blood flow to impaired balance and gait. Such impairment may cause falls among older alcoholics.
Researchers do not agree on the effect this brain shrinkage has on memory loss and problem-solving skills. Some studies show no effect, while others have reported some loss in those skills, associated with alcohol-induced brain shrinkage. However, these effects are usually reversed with alcohol abstinence. Even quitting drinking for 3-4 weeks has shown to reverse the effects on memory loss and problem-solving skills.
"More recent advances in imaging techniques are allowing investigators to study alcohol dependence itself. Scientists are beginning to measure alcohols effects on mood, emotional states, craving, and cognition while simultaneously assessing metabolic, physiologic, and neurochemical function in the brain," said NIAAA Director Enoch Gordis, M.D. "These innovations in imaging technology will help not only the alcohol field, but also all fields of medicine where biology and behavior are so closely linked."