Marijuana, although illegal on the federal level, has been legalized in 18 states and the District of Columbia for medical use and also for personal use by anyone over 21 in Washington and in Colorado. According to a 2013 survey conducted by Scientific America, 48% of Americans admit to using marijuana. As public opinion about marijuana changes, the need to understand the effects and consequences associated with its use is vital. What are the effects on the brain and the rest of the body? Does it matter when you start using marijuana? Furthermore, what effect does marijuana use have on a person's life, including school, work, family and friends? According to the National Institute on Drug Abuse, marijuana makes users feel euphoric by acting on the brain's reward system. Euphoria is caused by the release of dopamine in the user's system. Other effects may include heightened sensory perception (e.g., brighter colors), laughter, altered perception of time, and increased appetite. Marijuana also inhibits the formation of new memories and causes deterioration of coordination and balance. These reactions are caused by binding of receptors in the cerebellum and basal ganglia. The effect is similar to disorders normally associated with alcohol consumption. Habitual users may also develop acute psychosis, a fundamental disorder of the mind (as in schizophrenia) characterized by faulty or lost contact with reality, especially as evidenced by delusions, hallucinations, and disorganized speech and behavior (Merriam-Webster Dictionary). According to a Duke University study conducted by clinical psychologist Madeline Meier, the IQ level of marijuana users also decreases over time “people who have started...... middle of paper......sKhamsi, R. ( 2013, May 31) How safe is recreational marijuana. American scientist. Retrieved from http://www.scientificamerican.com/article.cfm?id=how-safe-recreational-marijuanaRogeberg, O. (2013). Correlations between cannabis use and IQ change in the Dunedin cohort are consistent with confounding by socioeconomic status. Proceedings of the National Academy of Sciences of the United States of America, 110(11), 4251-4254. Doi: 10.1073/pnas.1215678110Wenk, G. (n.d.). Retrieved from http://www.psychologytoday.com/blog/your-brain-food/201106/does-it-matter-when-you-start-smoking-marijuana Macleod, J., Oakes, R., Copello, A. , Crome, I., Egger, M., Hickman, M., & ... Smith, G. (2004). Psychological and social consequences of cannabis and other illicit drug use by young people: a systematic review of longitudinal studies in the general population. Hand,363(9421), 1579-1588.