Some drugs are more addictive than others. Thanks to scientific brain imaging, it has been discovered the addictive drugs and other substances become addictive because they change the neurons in the brain, as well as the way they behave. Most commonly, drugs impact the areas of the brain that recognize pleasure.
Drug abuse affects the brain by altering a person’s memory, judgment, decision-making skills, and perception of pleasure. Drug abuse changes the way neurons function in the brain. Once this happens, a person begins to perceive the drug as a prime source of pleasure, which causes the person to engage in risky behaviors in order to obtain the drug.
As the drug takes its hold, things that once seemed enjoyable no longer create the same pleasurable feelings, while the brain begins to perceive the drug itself as a source of pleasure. Drug may also affect the areas of the brain responsible for judgment, decision-making, and memory. This is one reason why drug abusers may behave recklessly, and why they begin engaging in riskier and riskier behavior in order to obtain the drug.
The abuse of addictive substances activates the brain reward system. Frequently activating this system with drugs can lead to addiction.
The brain reward system is naturally activated when we take part in actions that are good for us. It is part of our natural ability to adapt and survive. Whenever something activates this system, the brain assumes something necessary to survive is happening. The brain then rewards that behavior by creating feelings of pleasure.
Drinking water when we are thirsty, for example, activates the reward system, so we repeat this behavior. Addictive substances hijack this system, causing feelings of pleasure for actions that are actually harmful. Unfortunately, addictive substances have a far stronger effect on the brain reward system.