Addiction is defined as "being abnormally dependent on something that is psychologically or physically habit-forming" (dictionary.com). There are many different types of addiction. Drug, alcohol, nicotine and caffeine addiction are just a few types. It is important to examine addiction and describe the problems it causes in all aspects of a person's life.
The signs of addiction are obvious. Addiction starts with drug abuse, when a person makes the choice to use drugs, but addiction is not just "a lot of drug use." Recent scientific research shows that not only do "drugs interfere with normal brain functioning creating powerful feelings of pleasure, but they also have long-term effects on brain metabolism and activity." (Henderson 15). At a certain point, changes occur in the brain that can turn drug abuse into addiction, a relapsing illness. Those addicted to drugs suffer from compulsive drug and usage and cannot stop by themselves. Treatment is necessary to end this addiction (http://www.nida.nih.gov/Infofax/understand.html). Another sign is the compulsive use of drugs or alcohol regardless of negative consequences.
Addiction can be caused by numerous factors. People can be genetically predisposed, which means that a person's genetic makeup could cause it. It also can be caused by psychological and .
social problems. Uncontrolled stress can be a major factor as well. It also just may be that the substance is highly addictive and alters the brain's biochemical structure (Bender 45). The substances do this using the brain's reward system, also known as the mesolimbic reward system. The mesolimbic reward system raises the body's dopamine level, which gives off the feeling of pleasure (Bender 46). Addicitve substances hijack this reward system and flood the brain with dopamine. This causes the addict to crave the substance rather than being involved in normal daily activities because they don't feel the same amount of pleasure any more (Bender 46).