As we have seen in previous weeks, the human brain is an extraordinarily complex and fine-tuned communications network containing billions of specialized cells (neurons) that give origin to our thoughts, emotions, perceptions and drives. Often, a drug is taken the first time by choice to feel pleasure or to relieve depression or stress. But this notion of choice is short-lived. Repeated drug use disrupts well-balanced systems in the human brain in ways that persist, eventually replacing a person’s normal needs and desires with a one-track mission to seek and use drugs. At this point, normal desires and motives will have a hard time competing with the desire to take a drug.
Go to the website http://www.pbs.org/wnet/closetohome/science/html/animations.html, click Normal Neurotransmission (Dopamine), read the text, then click “Add Cocaine”. Do the same for Alcohol and Opiates. Then trace the neural pathway in the brain for two of the substances (cocaine, alcohol, opiates, etc.) and discuss how these drugs influence normal synaptic transmission. Compare the actions of cocaine, alcohol, and opiates. How are they alike? How do they differ