Kiran Mayee K
Addiction is a disorder of the brain's reward system which arises through transcriptional and epigenetic mechanisms and arises over time from chronically high levels of coverage to an addictive stimulus (e.g., morphine, cocaine, sexual intercourse, gambling, etc.). Most drugs affect the brain's "reward circuit" by inundating it with the chemical messenger dopamine. This reward system controls the body's capability to feel pleasure and motivates a person to repeat behaviors needed to thrive, such as eating and spending time with loved ones. This overstimulation of the reward circuit causes the extremely pleasurable "high" that can lead people to take a drug again and again.
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