Consuming alcohol in large quantities can impair cognitive and motor abilities, such as decision-making, coordination and the ability to form new memories. The inability to form new memories while intoxicated is referred to as an alcohol-induced blackout, which involves temporary memory loss.

Long-term use of alcohol in excessive amounts can cause brain damage by directly or indirectly affecting other organ systems. Brain damage from chronic alcohol use can result in an inability to form new memories and an impaired ability to retrieve existing memories.

See Related: Benefits of Quitting Alcohol

Why Alcohol Causes Memory Loss

Memory loss can be caused by both acute and chronic alcohol use. Consuming a large amount of alcohol quickly can temporarily impair the storage of new memories. When new information is acquired from a person’s environment, it is temporarily stored in short-term memory, which has a limited capacity. This information may then be transferred to long-term memory, and it can remain there for a few days or many years. Alcohol intoxication disrupts the transfer from short-term memory to long-term memory, impairing the formation of new long-term memories.

The period where people have an inability to form new memories due to alcohol is called an alcohol-induced blackout. These blackouts represent a temporary memory loss, which may be partial or complete. A partial blackout is more common, and people are able to remember some information about the blackout period when reminded. A complete blackout, however, involves an inability to remember any information about events during the blackout.

Long-term, excessive intake of alcohol can result in permanent or long-term memory loss. Alcohol can cause memory loss directly by damaging brain regions that are involved in cognitive and motor function. Chronic alcohol intake can also indirectly disrupt cognitive function by affecting other organ systems. For example, thiamine (Vitamin B1) deficiency is often responsible for dementia in chronic alcohol users.

Thiamine is not synthesized by the body and must be obtained through food sources. The chemical synthesizes neurotransmitters and also plays a critical role in breaking down sugars in the brain. However, alcohol directly interferes with the body’s absorption and utilization of thiamine. A thiamine deficiency can lead to Wernicke-Korsakoff syndrome, causing an inability to form new memories, trouble retrieving old memories and an abnormal gait.

Chronic alcohol intake can also impact the liver, causing cirrhosis that later leads to hepatic encephalopathy. Hepatic encephalopathy can cause cognitive deficits with attention and memory and create other psychiatric problems, such as depression and anxiety. Chronic alcohol use can also cause cardiovascular issues, which may lead to brain hemorrhages or reduced blood flow. These conditions damage brain regions involved in cognitive function and cause memory loss.

Signs of Alcohol-Induced Memory Loss

Alcohol intake, even in small amounts, has a negative impact on cognitive functioning. The degree of memory impairment increases with the amount of alcohol intake. The more someone drinks, the more likely they are to have a blackout period. Although individuals are unable to remember events that occur during the blackout, their short-term memories remain intact. This allows them to engage in conversations, drive a vehicle or perform other complex activities.

Some of the effects of an alcohol-induced blackout include:

  • Inability to focus on a conversation or follow a train of thought
  • Inability to remember recent events
  • Inability to follow normal speech

Chronic alcohol use may (not always) result in a permanent inability to form new memories. Some of the symptoms of long-term memory loss due to chronic alcohol intake include:

  • Impaired ability to retrieve existing memories along with an inability to form new memories
  • Inability to recognize or identify objects despite intact sensory capabilities
  • Impaired motor coordination
  • Impairments in complex cognitive tasks involving planning and decision-making

Factors Contributing to Alcohol-Induced Memory Loss

Many factors can influence the extent of alcohol’s effects on an individual. Some of these factors include:

  • Amount and frequency of alcohol intake
  • Duration of alcohol intake and the person’s age when alcohol intake began
  • Age and gender of the person
  • Genetic background and history of alcohol misuse in the family
  • General health influenced by lifestyle choices

Alcohol Detox and Treatment

In addition to memory loss, prolonged use of alcohol in excessive amounts can lead to liver and cardiovascular problems. Long-term use of alcohol can also cause a physical dependence on alcohol that may be severe enough to result in an addiction.

Treatment for alcohol dependence involves detoxification followed by various forms of therapy to prevent relapse. Stopping alcohol use can lead to withdrawal symptoms that range in severity. Symptoms appear about 6–24 hours after discontinuation of alcohol use and may last between 2–10 days. These symptoms tend to peak between 36–72 hours and include:

  • Insomnia
  • Nausea
  • Vomiting
  • Diarrhea
  • Increased heart rate
  • Anxiety
  • Excessive sweating

More severe symptoms may include:

  • Seizures
  • Agitation
  • Hallucinations
  • Mental confusion (delirium tremens)
  • Fluctuations in blood pressure

Treatment at a medical detox can help people cope with withdrawal symptoms, which can be particularly severe in cases of severe alcohol dependence. Treatment for alcohol dependence involves medications like naltrexone, which reduces cravings, or disulfiram, which interferes with the effects of alcohol intake. Cognitive-behavioral therapy can help people identify thoughts that lead to alcohol use and teach them strategies to cope with these thoughts. Support groups such as 12-step programs are also effective when combined with medications and behavioral counseling.

Prevention of Alcohol-Induced Memory Loss

One of the key ways to reduce the risk of memory loss is to restrict the amount of alcohol intake. Low levels of alcohol consumption can have protective effects on the brain. In fact, it is associated with a reduced risk of cognitive decline when compared to abstinence or moderate to heavy use. The Office of Disease Prevention and Health Promotion recommends limiting alcohol use to two drinks per day for men and one for women.

The risk of alcohol-induced blackouts may be underestimated by social drinkers, but research shows that blackouts are fairly common in social drinkers. However, excessive alcohol intake alone is not enough to cause a blackout. Other factors must also be present for a blackout to occur, including:

  • Drinking on an empty stomach
  • Rapid alcohol intake

Ways to avoid a blackout include

  • Having a meal before drinking
  • Allowing sufficient time between
  • Limiting drinks with high alcohol content

If you or a loved one suffers from alcohol misuse or addiction, The Recovery Village Columbus can help. Contact us today to learn more about treatment plans that can work well for your situation.

Sources

Rehm, Jürgen; et al. “Alcohol use and dementia: a systematic scoping review.” Alzheimer’s Research & Therapy, January 2019. Accessed August 31, 2019.

National Institute on Alcohol Abuse and Alcoholism. “Alcohol’s Damaging Effects On The Brain.” October 2004. Accessed August 31, 2019.

Moriyama, Yasushi; et al. “Primary alcoholic dementia and alcohol�[…]lated dementia.” Psychogeriatrics, September 2006. Accessed August 31, 2019.

White, Aaron M. “What happened? Alcohol, memory blackouts, and the brain.” Alcohol Research & Health, 2003. Accessed August 31, 2019.

Health.gov. “Appendix 9. Alcohol.” (n.d.). Accessed September 6, 2019.

Medical Disclaimer

The Recovery Village aims to improve the quality of life for people struggling with a substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare provider.