Most of the drugs that people abuse have their effect on the limbic system of the brain. The limbic system is located deep within the brain near the top of the brain stem. The limbic system produces the feelings of pleasure, pain, anger, and fear which characterize our emotions. All drugs of addiction work on our emotions. If a certain drug makes us feel very good, we tend to want to take that drug again and again. It is because of this temporary good feeling that we become psychologically addicted to a drug.
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