"Addiction is the repetitive, compulsive use of a substance that occurs despite negative consequences to the user" (Kuhn… et all, 1998). Addictive drugs will activate circuits in the brain that usually respond to 'normal' pleasures such as food. Developing an addiction to drugs depends on many factors in the life of the user like, family history, personality, mental health and life experiences. The actual drug taking is maintained by factors including changes in the brain as well as the deep desire to experience pleasure from the drug and avoid the discomforts of withdrawal (Kuhn… et all, 1998).
Both psychological and physical dependence occurs in people who are addicted to drugs. Addiction is so powerful because it mobilizes basic brain functions that are necessary for survival. These neural circuits exist in all people. The neural circuit causes people to enjoy life sustaining activities. When a person experiences pleasure, he/ she is likely to repeat this activity. This neural circuit is often known as the reward pathway. When this pathway is destroyed a person loses interest or motivation in pleasurable life sustaining activities. Addictive drugs act as activators of the pleasure pathway in the brain. Stimulants like opiates, alcohol and nicotine may act as a substitute for natural pleasures like food (Kuhn… et all, 1998).
Addiction is considered a brain disease because it changes these structures in the brain as well as how it works. It does this by disrupting the normal, healthy functioning of the brain. Although harmful, addiction is both preventable and treatable. Drugs target the reward system or "pleasure pathway" by increasing the release of dopamine. An excess of dopamine produces a "high" that makes the user feel good. This feeling often leads to repetitive behavior. The reward pathway is responsible for making sure that you repeat a behavior whenever possible by connecting to regions of the brain that control memory and behavior. The reward pathway also signals the brains motor center and strengthens the "wiring" to help you achieve the reward, i.e. repeat the pleasurable experience. Over time the brain begins to adjust so that it can no longer experience pleasure in natural ways, it needs the drug in order to feel good. The lack of being able to feel natural pleasure is often what makes it so hard for an addict to give it up (Scholastic, 2009).