Effects Of Alcohol On The Brain
Alcohol’s effect on the brain causes intoxication symptoms over the short-term, but with long-term, heavy alcohol use, a person may experience the following effects on brain functioning.
Alcohol can cause short-term memory impairment, as it may lead to blackouts, in which a person forgets events that happened while they were under the influence of alcohol. Unfortunately, alcohol can also cause lasting memory impairment. A study of people with alcohol use disorders found that these individuals had smaller brain volumes in the frontal lobes and the hippocampus. They also showed deficits in episodic memory, which is the ability to remember details of events.
Increased Risk Of Dementia
Because alcohol misuse damages the brain, people who drink excessively are more likely to develop dementia. In fact, research shows that heavy drinking changes the structure of the brain, leads to cognitive impairment, and increases the risk of all types of dementia.
Effects On The Teenage Brain
Unfortunately, the negative effects of alcohol on the brain are especially likely to affect teenagers. Teenagers who binge drink or meet the criteria for an alcohol use disorder, which is the clinical term for an alcohol addiction, show deficits in cognitive functioning, changes in brain structure, and differences in brain activity when compared to those who do not drink.
Worse Mental Health
People sometimes wonder, “How does alcohol affect your mental health?” The answer is that heavy alcohol use increases the risk of mental health problems like depression and anxiety. Alcohol is thought to affect a brain chemical called GABA, which inhibits the stress response in the brain and body. This means that people may use alcohol as a source of self-medication for stress and anxiety. Over time, alcohol changes the way that the brain produces and reacts to GABA, which actually makes mental health worse.
Alcohol-Related Brain Damage
Chronic alcohol misuse can result in severe brain damage, which can occur directly due to alcohol misuse, or as a result of poor health among individuals who are addicted to alcohol. For instance, poor nutrition is linked to thiamine deficiencies among individuals with alcohol use disorders.
Thiamine deficiency can lead to a severe brain condition called Wernicke-Korsakoff syndrome. This condition begins with a temporary condition called Wernicke’s encephalopathy, which causes coordination problems, nerve damage in the muscles that move the eyes, and confusion. Many people who experience Wernicke’s encephalopathy go on to develop Korsakoff’s psychosis, a chronic, highly debilitating brain disorder. This condition causes problems with learning and memory and can lead to coordination difficulties. Individuals who have Korsakoff’s psychosis may not remember the details of conversations or events that have occurred within the past hour.
Even young drinkers may develop early signs of alcohol-related brain damage and impairment. For example, young binge drinkers, aged 18 to 24, have been found to show impairment in various regions of the brain, including the frontal lobe, temporal lobe, and hippocampus. This means that heavy alcohol use, even among young adults, can affect memory, decision-making, and speech. If left untreated, binge drinking can lead to an alcohol use disorder, which over time can damage the brain further and lead to severe problems with brain functioning.
Stages of Alcohol Intoxication
Another part of understanding what happens to the brain when you drink alcohol is learning about the stages of alcohol intoxication. According to medical experts, alcohol intoxication occurs in seven potential stages.
After just one drink, the blood alcohol content (BAC) rises to as high as .05. You may not feel or appear intoxicated yet, but because of alcohol’s effects on the brain, your reaction time and judgment may be slightly impaired.
You may describe this stage of alcohol intoxication as “being tipsy.” At this stage, the BAC rises as high as .12, and a person begins to feel relaxed, happy, and confident, because alcohol is increasing levels of the feel-good brain chemical dopamine. Memory and decision-making capacities are becoming more impaired.
This next stage of alcohol intoxication affects various lobes of the brain, including the occipital lobe, temporal lobe, and frontal lobe. Because of these effects, a person may experience blurry vision, slurred speech, and difficulty with self-control. You may begin to experience nausea or vomiting during this stage.
With a BAC of 0.18 to 0.3, people become increasingly disoriented. An area of the brain called the cerebellum, which is responsible for movement, is impaired, which results in coordination problems. A person in this stage of intoxication may have trouble walking on their own, and they are at risk of blacking out.
At around a BAC of .25, a person will reach a state of alcohol-induced stupor. This means that their cognitive and physical functions are severely impaired.
This stage of alcohol intoxication, which occurs around a BAC of .35, places you at risk of death or lasting brain damage. When the BAC is this high, alcohol impairs breathing, circulation, and reflexes, leading to coma.
If alcohol consumption is heavy enough, the BAC will reach as high as over 0.45. In this state, death is possible, because a high BAC can lead to alcohol poisoning. The effects of alcohol on the brain may also be strong enough at this BAC level to shut down areas of the brain that control breathing and other vital functions.
How Does A Normal Brain Compare To A Brain Of Someone With Alcohol Use Disorder?
Research has shown that people with alcohol use disorders are likely to experience cognitive impairment, which means that brain functioning of those with alcohol use disorders is typically weakened when compared to a healthy brain. Studies also show that chronic alcohol misuse causes functional changes in brain regions associated with planning, problem-solving, and controlling impulses. The healthy brain is likely to perform better than an alcohol-damaged brain on these tasks. People with healthy brains also tend to show better functioning in areas that control memory and visual processing.