Science of Addiction

Drugs and alcohol stimulate the release of a chemical called dopamine (pronounced dough pah meen)—the brain’s “reward system” that stimulates feelings of pleasure.

Unnaturally high levels of dopamine can lead to chemical imbalances in the brain. These imbalances can cause a person to lose control over how much pleasure is needed. This loss of control can lead to craving for drugs or alcohol.

The limbic system of the brain—part of the body’s Central Nervous System—plays a role in fundamental human urges such as eating, sleeping, and sexual pleasure.

The limbic system (“limbic” is a Latin word that means “border”) is connected to the neocortex (the part of the brain responsible for judgment and conscious control of behavior) as well as to parts of the brain that regulate basic body functions (such as heart rate and temperature).

The limbic system is very sensitive to excessive dopamine release associated with drug and alcohol dependence. In fact, substance dependence can temporarily or permanently change the function of the limbic brain until eventually, it starts to override the judgment of the neocortex. The limbic brain urges an individual to use alcohol or drugs by causing the intense feeling that these substances are necessary for survival.

The scientific discovery of addiction’s physical effect on brain function was a breakthrough in helping people understand that dependence on drugs or alcohol is not simply a “behavior problem.” (Similarly, another scientific breakthrough helped people understand that dependence on cigarettes is not simply a behavior problem, but a physical craving for the drug nicotine as well.)

This understanding of brain function helped people realize that recovery from addiction requires medical treatments that focus on relieving symptoms and restoring the natural balance and functions within the Central Nervous System.

Science of Addiction

Changing the brain’s “reward system”

Drug and alcohol addiction affects the “limbic brain”

Breakthrough in understanding addiction