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The Effects Of Drugs And Alcohol Abuse On The Brain

Joseph Sitarik, DO

Medically reviewed by

Joseph Sitarik, DO

February 28, 2019

It may be easy to see the effects of drugs or alcohol on the body, but the effects of substance abuse may go deeper than the surface. In fact, all substance abuse affects the brain. To understand the way drug or alcohol abuse affects the brain, it is necessary to understand how the brain works.

How The Brain Functions

It is helpful to visualize the brain as a center of communications—one that is constantly sending messages from one circuit to another. These messages are responsible for all functions in the body and brain, such as thoughts, feelings, and actions. Messages are sent by way of chemical signals (neurotransmitters), from one brain cell (neuron) to the next. Once a neurotransmitter crosses from one cell to the next, the message that neurotransmitter carries is successfully delivered.

How Do Substances Work In The Brain?

To start, the Genetic Science Learning Center states that, “drugs of abuse affect the brain much more dramatically than natural rewards, such as food or social interactions.” Substances essentially work to disrupt the brain’s natural communications’ system. As explained by the National Institute on Drug Abuse (NIDA), “some drugs, such as marijuana and heroin, can activate neurons because their chemical structure mimics that of a natural neurotransmitter.” However, mimicking is not the real thing, and substances cannot activate the brain’s neurons the way that its own chemicals do. Therefore, the messages which result from these transactions will be abnormal.

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Effects On The Brain

So what does a disruption in communication mean for the brain? In the short term, it often means a feeling of euphoria, the “high” many people who abuse substances will experience. Many substances will produce a surplus of dopamine, which makes a person feel pleasure. The brain generally produces a feeling of pleasure when a person experiences something which is rewarding, such as a pleasant smell, or seeing someone that person loves. Substance abuse allows for a much stronger, or faster, feeling of pleasure, or one of longer duration. Over time, this routine rewires the brain, making it want that intense pleasure all the time, or at least again and again.

Why can’t we just choose not to engage in substance abuse if we know what it does to the brain? The way drugs or alcohol affect the brain actually makes it very difficult to stop abuse. As NIDA warns, “Our brains are wired to ensure that we will repeat life-sustaining activities with pleasure or reward. Whenever this reward circuit is activated, the brain notes that something important is happening that needs to be remembered, and teaches us to do it again and again without thinking about it.”

How Substances Affect The Brain Long-Term

Beyond changing the order of functions in the messages which are sent, substances affect the brain long-term as well. The brain responds to the abundance of dopamine levels produced by substances by overcorrecting. In other words, as NIDA states, “the brain adjusts to the overwhelming surges in dopamine (and other neurotransmitters) by producing less dopamine or by reducing the number of receptors that can receive signals.” What eventually results is that the reward circuit of the brain of a person who abuses drugs or alcohol may not feel the impact of dopamine as strongly as it did before abuse. This in turn may minimize overall that person’s ability to feel pleasure.

Once a person’s pleasure in life is reduced, that person may lose interest in activities or obligations, may feel depressed, or may experience any number of adverse effects. What often happens, though, is that a person who has abused drugs or alcohol and experienced this change tends to seek out the missing feeling, the euphoric feeling first found with substance abuse.

The Adverse Effects On The Developing Brain

Addiction is particularly dangerous to the developing brain, such as for adolescents. According to the Science and Management of Addictions Foundation (SAMA), “interference with neurotransmitters can directly damage fragile developing neural connections.” SAMA also explains that the habits formed which cause a person to continually seek use of substances are especially harmful to younger people. This is largely because, “repeated action becomes habit and the habits of thought, perception, and reasoning developed in childhood and adolescence can stay with a person throughout his or her lifetime.”

Can You Reverse The Effects Of Substance Abuse?

Because substance abuse conditions the brain to desire continued use of substances, reversing this process is difficult. However, with the right treatment or therapy, recovery is highly possible. One important way a person can work to achieve recovery is through behavioral therapy, which teaches participants to build a lifestyle free from substance abuse. Of course, for the initial detoxification period, medication or inpatient care may be necessary, but abstinence is often key to long-term success. Essentially, it is imperative for those affected by substance abuse to teach their bodies to work against the brain’s learned notion that they need substances. Instead, people in recovery strive to avoid substance abuse, and focus on daily life activities which are devoid of the influences of drugs or alcohol.

How To Get Help With Treatment

Despite the dark facts, millions of people still struggle with substance abuse every day. If you are one of those people, you don’t have to face this battle alone. Treatment awaits you, with trained professionals willing to help you along the way. For more information about treatment, or to get in touch with resources, contact us at today.

Learn.Genetics - Drug Use Changes The Brain Over Time

National Institute On Drug Abuse - Drugs And The Brain

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