Get in tune with your mental health and spread awareness by learning about the link between mental health and substance use and how it impacts you, your friends, loved ones, and the community.

If you’re an overall healthy person, you may wonder why people even try drugs in the first place. After all, since childhood, most of us have been told drugs are bad and to “just say no”.

The limbic system controls many parts of your life, but is probably most known for releasing dopamine or “the pleasure hormone”.

Whenever you do something you enjoy, such as eating chocolate, intimacy, or snuggling with a pet, the brain then releases a small “hit” of dopamine that makes you feel good.

When drugs or alcohol are consumed, it gives the reward circuit a higher hit of dopamine than a natural response would produce, which may feel amazing at first. If you keep doing this, the body gets used to higher doses of dopamine and eventually registers it as a normal[3].

Rather than feeling good from this heightened reward, an addict develops a “need” for the substance just to feel okay. The brain would need even more of it just to trigger any sense of pleasure. Can you see how that can easily become a problem?

While addiction harms the entire reward system, it’s especially detrimental to specific sections of the limbic system. Once you read more about them, you’ll see why it causes people to behave differently under the influence.

Even though humans have become more civilized, we’re still hardwired with primitive survival instincts. Maybe even more surprising, this deeply ingrained behavior is controlled by a miniscule part of the limbic system called the amygdala.

Imagine you’re driving on your usual route home from work, when the car in front of you suddenly slams the brakes. You act quickly and also slam your brakes. This is triggered by an acute stress response, more commonly called the fight, flight, freeze, or fawn response [4].

In this scenario, the body automatically chose “flight” to escape a rear-end collision.

Other amygdala functions include controlling your emotions and creating memories. So, the next time you drive on that same road where you almost crashed, the memory of the event may make you feel tense even if there are no other cars around for miles.

While it may be irrational when there’s no visible threat, this brain function helped humans survive this long. When drugs or alcohol enter the system, this can cause your amygdala to have a delayed reaction to potential threats, such as losing control of your vehicle.

All it takes is a one-second delay in reaction time can have fatal consequences. It’s not worth the risk of putting yourself and other people in danger.

In the cases where the fear is irrational, there’s another important part of the brain that -in a sense- combats fear responses with a more practical thought process.

This part of the brain controls your thought process, problem solving skills, manages your self-control, and helps bring you back to reality [3].

Say you have a job interview for your dream job in a couple of days.

You plan ahead of time by looking over some commonly asked questions for this position, print out a copy of your resume, and pick out your best outfit. Planning ahead for something you anticipate, like an interview, is just one function of the prefrontal cortex.

The big day comes, and you’re on your way to the interview. You may feel nervous or even afraid, thanks to the ol’ amygdala reminding you of the potential threat of rejection.

You could theoretically turn around, go home, and no show. You’d avoid the in-person discomfort of possible rejection, but that would also guarantee you don’t get the job. This is an example of reasoning, also operated by the prefrontal cortex.

The prefrontal cortex develops slower than the rest of the brain, fully mature around age 25, though some studies argue it could take even longer.

Regardless, that’s still quite a while from adolescence, which is a very confusing point in life where reasoning skills and impulse control would be beneficial.

Introducing mind-altering substances at a young age can slow or even harm a developing brain. Impulsive behavior, emotional outbursts, and lack of coordination are just a few consequences of drug or alcohol misuse and the side effects on the prefrontal cortex.