Final answer:
The primary organ affected by addiction is the brain. Drug addiction involves changes in the brain's chemistry, particularly the dopamine system. Rehabilitation from addiction generally requires psychotherapy and may include the use of other psychoactive substances in the treatment process.
Step-by-step explanation:
The primary organ affected by addiction is the brain. This impact occurs because psychoactive drugs generally produce their effects by affecting brain chemistry. Substances such as psychoactive drugs can alter mood, perceptions, thinking, and behavior. When these drugs are used, they can act as either agonists, enhancing the activity of neurotransmitters, or as antagonists, decreasing their activity. One key neurotransmitter involved in addiction is dopamine, which is closely associated with the reward system in the brain.
Drug addiction can be described as the compulsive use of a substance despite the negative consequences it may entail. Over time, the addicted individual's brain can change, as suggested by imagery such as PET scans showing dopamine binding in normal versus addicted individuals. The scans highlight that addicted individuals have fewer dopamine receptors available, thereby potentially disrupting the sense of pleasure and contributing to the addiction.
Addiction can lead to dependence, which can be either physical or psychological. Dependence develops when stopping the drug causes withdrawal symptoms. The process of rehabilitation typically requires psychotherapy and may sometimes include the use of alternative psychoactive drugs to manage withdrawal and aid in recovery.