Alcohol
produces its most prominent effects by making significant changes in the brain’s normal chemical environment. In a person with alcoholism, some of these changes persist over time and lead to lasting, disruptive structural and behavioral problems. In a study published in April 2014 in the journal PLOS One, a team of researchers from Spain and Great Britain used several modern technologies to conduct a detailed investigation of how alcohol damages the brains of people affected by alcoholism. These researchers found that chronic exposure to excessive amounts of alcohol literally alters the structure of individual nerve cells in the brain.
Alcohol and the Brain
When consumed in amounts higher than the liver can safely eliminate, alcohol is poisonous to the function of major organs throughout the human body. In the brain, this poisonous effect manifests in the short run as symptoms of alcohol intoxication such as loss of normal muscle/body control, an inability to remember things or think clearly, visual distortions and speaking difficulties. Intoxicated people who drink heavily may also experience larger slips in their memory or full-on “blackouts,” which effectively erase entire chunks of time from recall. The National Institute on Alcohol Abuse and Alcoholism notes that a number of factors influence how much alcohol consumption alters the brain function of any given individual. These factors include that individual’s overall level of good health, frequency and amount of alcohol intake, history of alcohol exposure in the womb, lifetime drinking history, age at initial alcohol consumption, hereditary susceptibility to alcohol, alcohol-related family background and demographic indicators such as gender, age and educational status.
Alcoholism and Brain Damage
The persistent presence of excessive amounts of alcohol leads to a physical dependence on drinking by creating ongoing chemical changes in the brain’s pleasure center. This physical dependence is the defining characteristic of alcoholism. However, the chronic heavy drinking associated with alcoholism produces damaging changes in other parts of the brain as well. In particular, alcoholism typically leads to degraded function in the prefrontal cortex, an area of the brain responsible for the higher-level faculties that largely make human beings distinct as a species. Examples of the impacted faculties include rational thinking, the ability to make decisions, process emotions and control impulsive behaviors, plan for the future, form memories and make sense of new information and the ability to make accurate risk/reward assessments for any given situation. Even when alcoholics get help and stop drinking, much of the damage done to the brain can linger for extended amounts of time or remain as permanent deficits.
Exploring the Underlying Cause
In the study published in PLOS One, researchers from Spain’s University of the Basque Country and Basque Institute of Legal Medicine and Great Britain’s University of Nottingham used several modern investigative tools to examine the underlying causes for the prefrontal brain damage found in people affected by alcoholism. This examination was done postmortem on 20 people who had received an alcoholism diagnosis while still alive. For comparison’s sake, the researchers also made postmortem examinations of the brains of 20 people unaffected by alcoholism while still living. Specifically, they looked for changes in the structure of the individual brain cells in each person in both of these groups. After completing the comparisons between the two groups, the researchers concluded that people affected by alcoholism have clear signs of damaging changes in some of the key materials that form the brain’s nerve cells. These changes not only degrade the function of individual cells; they also interfere with the cells’ ability to communicate normally with each other and form the networked connections that give the prefrontal portion of the brain its general organization and everyday capacity. The researchers also looked at other areas of the brain in both the alcoholism-affected group and the non-alcoholism-affected group. They found evidence of similar alcohol-related brain damage in these areas, but this damage was not as uniform as that found in the prefrontal cortex. The researchers believe that this fact may indicate that different areas of the brain have unique risks associated with chronic, excessive alcohol exposure. The study’s authors are the first researchers to report such detailed information on how alcoholism damages the brain. They believe that their findings lay the groundwork for a further, multidisciplinary exploration of the root process through which alcohol produces its harmful brain effects. They also believe that their findings may ultimately help set the stage for the development of new, improved treatments that can restore some of the brain function lost in people affected by alcoholism.