How does addiction work?

Kelly Traver
Internal Medicine

Deep in the brain, there are areas called the nucleus accumbens and ventral tegmental areas, also known as "pleasure centers." You get a pleasurable sensation from the release of dopamine when these areas are activated. Some people have a much more intense reaction to a given stimulus than others by generating more dopamine. Dopamine feels good and captures your attention, but too high a level can cause hallucinations or distorted thinking, and when high levels of dopamine are released on a repeated basis, larger and larger amounts are needed to have the same effect because receptors on the nerve cell membrane become less and less responsive. This phenomenon is known as tolerance. After a while, not only does it take higher levels of dopamine to have the same effect, even normal levels of dopamine don't feel as if they are enough anymore. Because normal levels feel low, all the brain can think about is how to get the dopamine into a range that will feel normal again. Some drugs, such as methamphetamine, trigger this physiology quite quickly. People often become addicted to this drug after one or two exposures. Other drugs differ in their ability to cause addiction, and people also differ in how easily they can become addicted.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.