Dopamine: The Brain’s Pleasure Drug

When we think of drugs, we often think of the adverse effects that can be observed from the outside. Yellow teeth, saggy skin, hair loss are all common signs that someone is using drugs. But there is a lot that is happening that can’t be visibly observed.

Drug use changes your brain. From the very first time, to all subsequent uses, drugs are modifying the chemicals in your brain. But how do drugs actually do this?

Your brain has natural reward mechanisms. These mechanisms control the reward you feel in response to food, sex, or even just performing an activity you enjoy. The reward in your brain is a chemical called Dopamine. It is released from one brain cell to another during a pleasurable sensation to signal that you should feel pleasure.

Dopamine is released in greater amounts when affected by drug vs. natural reward.

When your brain releases dopamine, it binds to two different receptors in your brain. The first receptor, the D1 receptor causes the pleasurable sensation. The other receptor, the D2 receptor causes inhibition of aversive stimuli. It is when these two receptors are out of balance that addiction occurs.

The longer that a drug stays attached to the receptor can also control how addicting the substance is. For natural reinforces, dopamine is only released for a short amount of time, but for drugs, dopamine is released for long periods of time. This floods the dopamine receptors with molecules that they need to bind to. Thus, drugs cause a longer change in your brain than natural reinforcers do.

With subsequent use of drugs, your brain adjusts to produce more and larger receptors. Instead of binding to the pleasurable receptors, the drug binds to the D2 receptors and this causes the feeling of craving that follows.

The brain region dopamine is released in is called the nucleus accumbens. This region of the brain is responsible for cognitive processing of reward, punishment, and motivation. It is important to understand the role that the nucleus accumbens plays in addiction because it is in charge of the motivation to repeatedly take drugs.

Drugs change your brain. That is a very scary statement and one that shouldn’t be taken lightly. This is why it is important to tell people the serious consequences of using drugs before they begin using them. It’s easy to change our brain using drugs, but very very hard to change it back.

 

Image from National Institute on Drug Abuse

For more information on how specific drugs effect the brain click here

Information for this blog found in Cell