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This Is Your Brain on Drugs

How substance use disorder affects the brain, and what can be done about it.

Key points

  • The excessive use of alcohol and other substances can take the brain's reward center hostage.
  • The brain can take time to recover, and people can struggle with cravings and various brain deceptions during that time. 
  • Regular, vigorous exercise can help speed up the recovery time.

We now know that chronic substance use—of both alcohol and drugs—actually changes the chemistry and structure of the brain. That sounds serious, and it is, but there are some positives and some solutions as well, which I’ll get to in a minute. First, the science.

A rewards program gone wrong

There’s a section of the brain called the "reward center" that is comprised of two parts: the ventral tegumental area and the nucleus accumbens. In essence, this reward center keeps us alive. It controls our incentive to eat, sleep, fall in love, avoid danger, and all the things we need to do in order to prosper as humans.

The problem is, when a person starts abusing drugs or alcohol, these substances take the reward center hostage by altering its structure and chemistry. When that happens, you start thinking your survival depends on getting drugs or alcohol rather than food, sleep, sex, and so on. Unfortunately, these brain changes can happen quickly—sometimes in less than a month of chronic drug or alcohol use.

A little like a virus, the affected chemistry in the reward center then moves to other parts of the brain, namely the pre-cortex and cortex. Once there, judgment becomes impaired. This is when people using drugs or alcohol start thinking and doing things that run completely counter to their well-being.

And it’s why, at a certain point, they have such poor insight into their addiction. They don’t recognize that it’s destroying their lives.

The rebound starts when the drugs stop.

Back to the ongoing hostage situation with the brain’s reward center. When a person gets into rehab and/or stops using, that’s when hostage negotiation begins. It’s when your brain starts freeing itself from its captor (drugs and alcohol).

That said, the timeframe of the negotiation varies from person to person, depending on overall mental and physical health, living situation, trauma, age, gender, and so on.

A key point regarding age: Researchers have known for years that the human brain continues to develop up to age 25 or so. But it is particularly susceptible to drug- and alcohol-induced changes until around age 21. This means that addiction can be more serious and cause longer-term damage when it happens in young people compared to older adults.

The brain recovers—but it takes time.

As I mentioned, when a person starts his or her recovery, that’s when the toxins start leaving the brain and body. And it’s when the brain can start returning to normal. But this is a slow process, and meanwhile, the cravings and brain deceptions remain. In essence, the reward center is still saying, “Keep using; I need you to keep using, and you will be rewarded.”

That’s a big reason why the early days, weeks, and months of recovery are such a challenge. And it’s why it is especially important at this time, when relapse risk is highest, to stick with all aspects of your recovery. This may include AA, NA, or SMART meetings, inpatient or outpatient therapy, seeing a therapist, having a sponsor, getting help for any co-occurring conditions, such as depression or trauma, staying with your medication-assisted treatment (MAT), and so on.

New research: Exercise may hasten brain recovery.

The big question with all this is… how do you get the brain back to normal as quickly as possible, so cravings subside, and your brain is no longer telling you to use? Researchers believe it often takes around 18 months to return to normal brain function, but is there a way to shorten that timeframe?

Quite possibly, yes. It turns out that regular, vigorous exercise, such as running, fast walking, swimming, and cycling, may be able to speed things along.

In a recent study, researchers found that normal brain chemistry and structure returned significantly more quickly for those in recovery when they did 30 to 45 minutes of exercise three times a week, compared to a control group of non-exercisers. That’s great to know, especially when you include all the other physical and mental benefits that regular exercise brings.

Helping to end the misplaced stigma of addiction

Maybe the only good thing about SUD affecting the brain is this: It proves beyond a doubt that SUD is not a weakness of character, lack of willpower, or evidence that you’re a bad person because of your addiction. This scientific evidence has helped decrease the stigma that surrounds SUD, but we still have a ways to go on that front. Nevertheless, it’s progress.