Addiction and the Human Brain

As a board-certified addiction medicine physician, Dr. Kathleen Whaley has cared for patients in both New York and Indiana. Dr. Kathleen Whaley currently works at Conifer Park in Rochester, New York, where she draws on an in-depth understanding of neurological addiction processes.

At its core, addiction is a change in the brain's reward system. The human brain naturally reinforces behaviors that feel good, largely through the release of neurotransmitters like dopamine. Addictive substances activate the same processes, despite the fact that the substances themselves are harmful to the body.

Dependence occurs because those same substances overstimulate the brain's reward system. They increase the feelings of pleasure associated with taking the drug, which causes the person to repeat the behavior to excess. The person's brain begins to prioritize use of the drug above other, healthier alternatives. Furthermore, the brain learns to associate certain situations and stimuli with the pleasure of the drug. Those cravings further intensify the person's need to use the substance.

In time, these floods of pleasure-causing chemicals inhibit the brain's ability to produce normal levels of neurotransmitters. Without the drug, the person feels listless, depressed, and unable to enjoy other activities. Normal use of the drug becomes baseline and the person needs more of it to feel “high"; the increased use further damages the brain and body.