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How Alcohol Affects the Brain

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Medically Reviewed By: Diana Vo, LMFT

November 28, 2023

Table of Contents

Alcohol can profoundly affect the complex structures of your brain, causing short-term and long-term damage. How alcohol affects the brain depends on many factors, including slurred speech, impulsive behavior, slowed reflexes, and more.

Consuming alcohol disrupts signaling between brain cells (neurons). This triggers these immediate side effects of intoxication:

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  • Slurred speech.
  • Impulsive behavior.
  • Slowed reflexes.
  • Impaired memory.

Sustained and heavy drinking causes the brain to adapt to those blocked signals by responding more intensely to chemical messengers in the brain known as neurotransmitters. After alcohol has exited your system, the brain keeps over-activating neurotransmitters, leading to painful and extremely uncomfortable withdrawal symptoms that can damage brain cells. Sudden alcohol withdrawal and binge drinking episodes can worsen this damage.

The long-term effects of alcohol on the brain as a result of chronic abuse include:

  • Psychological dependence on alcohol.
  • Addiction in the form of alcohol use disorder.
  • Chronic and aggravating brain disorders.

An awareness of how alcoholism affects the brain could help you to prevent the development of addiction and brain damage.

How Alcohol Affects the Brain

How does alcoholism affect the brain?

Alcohol intoxication can interfere with the equilibrium of neurotransmitters in the brain, bringing about short-term changes in the brain. In the event of chronic alcohol abuse, the brain adapts to compensate for the effects of alcohol, leading to functional and structural changes in some areas of the brain.

How does alcohol affect the brain and central nervous system, precisely?

Among the most disturbing long-term effects of alcohol abuse on the brain is the possibility of developing physiological dependence as well as physical dependence on alcohol. When this occurs, withdrawal symptoms – both physical and psychological will manifest if alcohol consumption is discontinued or significantly reduced. Additionally, you will experience powerful cravings for alcohol in its absence.

When dependence on alcohol develops, this heightens the risk of alcoholism, clinically diagnosed as alcohol use disorder. This chronic and relapsing brain condition is characterized by the compulsive consumption of alcohol in spite of significant negative outcomes for health, relationships, and overall functioning.

Some of the mental effects of alcohol abuse will fade when you quit drinking, but others may persist, potentially triggering long-term health complications.

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How Does Alcohol Affect the Brain?

Alcohol intoxication is the result of the immediate effects of alcohol on the CNS (central nervous system). These effects can dramatically vary depending on many variables, such as:

  • Amount of alcohol consumed.
  • How often you drink alcohol.
  • Your physical frame and weight.

Some symptoms of alcohol intoxication may present after just one or two drinks – mild physical and cognitive impairment, for instance. Heavy drinking and binge drinking can trigger potentially fatal alcohol overdose, also known as alcohol poisoning.

Alcohol affects the brain by influencing its information-processing and communication pathways. When you consume too much alcohol, this brings on adverse mental outcomes like:

  • Confusion.
  • Impaired decision-making.
  • Reduced motor coordination.

Your Brain on Alcohol

While the whole body absorbs alcohol, the primary effects are felt in the brain.

Alcohol intoxication is the presentation of these effects, and it unfolds over multiple stages:

  • Subliminal intoxication: When BAC (blood alcohol content) reaches 0.05, this is the initial stage of intoxication. Although you may not appear drunk, you may experience slight changes in reaction times, judgment, and behavior. This stage typically begins after consuming one standard drink.
  • Euphoria: When BAC falls between 0.03 and 0.12, your brain releases increased amounts of dopamine, a chemical associated with pleasure and positive mood. Your memory and reasoning may be compromised at this stage of intoxication. You are liable to feel confident and more relaxed.
  • Excitement: When BAC rises to 0.25, you are legally intoxicated. Psychological effects include a loss of motor skills and slower reaction times together with further impaired judgment and mood swings. Physical symptoms include vomiting and nausea.
  • Confusion: When BAC levels are between 0.18 and 0.3, this impacts the cerebellum, an area of the brain responsible for coordination. Blackouts may occur at this stage of intoxication, involving a temporary loss of consciousness.
  • Stupor: If your blood alcohol content reaches 0.25, this can cause signs of alcohol poisoning to manifest. All mental and sensory functions are drastically impaired by this point. Also, the risk for suffocation, losing consciousness, and injury increases substantially.
  • Coma: At a BAC level of 0.35, you run a strong risk of coma due to the way alcohol compromises motor responses, respiration, reflexes, and circulation. Going into an alcoholic coma can be life-threatening.
  • Death: BAC levels over 0.45 can cause fatal alcohol poisoning or complete failure of the brain.

Long Term Effects of Alcohol Abuse

Research indicates that those who exceed moderate drinking guidelines are at increased risk of the following long-term health complications:

  • Depression.
  • Anxiety.
  • Mood disturbances.
  • Disrupted sleep patterns.
  • Heart disease.
  • Liver disease.
  • Weakened immune system.
  • Cancer.

Chronic alcohol abuse is implicated in the development of brain disorders such as WKS (Wernicke–Korsakoff syndrome). According to research, 80% of those with alcohol use disorder have a vitamin B1 (thiamine) deficiency. WKS involves two separate conditions:

  1. Wernicke’s encephalopathy: A severe and short-lived brain condition characterized by impaired muscle coordination, mental confusion, and oculomotor disturbances – paralysis of nerves responsible for moving the eyes.
  2. Korsakoff’s psychosis: A debilitating, long-lasting brain condition that occurs in up to 90% of those with Wernicke’s encephalopathy. Persistent memory and learning problems are central to this condition.

All long-term abuse of alcohol is likely to trigger alcohol use disorder (the clinical descriptor for alcoholism or alcohol addiction).

Alcohol use disorder is diagnosed according to criteria in APA’s benchmark diagnostic tool, DSM-5-TR. A mental health professional or addiction specialist will ask you eleven questions based on your alcohol consumption over the previous year. Two or three positive responses indicate mild alcohol use disorder. If you respond positively to four or five diagnostic questions, this is classified as moderate alcohol use disorder. Severe alcohol use disorder involves the presentation of six or more criteria in a twelve-month period.

What can you do if you are diagnosed with this incurable and chronic brain disease? Fortunately, we can help you get back on track here at Renaissance Recovery Center.

Alcoholism Treatment at Renaissance Recovery

While alcoholism is a chronic and relapsing disease with no cure, most alcohol use disorders respond positively to treatment. We can help you engage with outpatient therapy for your addiction and any co-occurring mental health disorders at Renaissance Recovery.

For anyone who needs more support and structure in their recovery, we offer more intensive outpatient programs in the form of PHPs (partial hospitalization programs) and IOPs (intensive outpatient programs).

All our treatment programs are delivered by credentialed and experienced medical professionals and addiction specialists. Your treatment team will personalize a treatment plan drawing from these interventions:

When you complete your treatment program at Renaissance, you can shift down a less intensive form of therapy or transition directly back into sober living. Either way, you will be equipped with the coping mechanisms, relapse management strategies, and life skills you need to maintain your sobriety in the face of stressors and temptation.

Start building a robust foundation for your recovery from alcoholism at Renaissance Recovery Center. Call 866.330.9449 for immediate assistance.

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At Renaissance Recovery our goal is to provide evidence-based treatment to as many individuals as possible. Give us a call today to verify your insurance coverage or to learn more about paying for addiction treatment.

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Joseph Gilmore has been in the addiction industry for three years with experience working for facilities all across the country. Connect with Joe on LinkedIn.

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