PSC 101 Lecture Notes - Lecture 5: Excessive Daytime Sleepiness, Digital Negative, Sleep Paralysis
Document Summary
Lead to loss of hedonic response (drug use may no longer be pleasurable), motivation to use drugs can remain high due to hyperactivity of dopamine. Potentially years after drug use has stopped. Pain relievers such as vicodin/oxycontin are abused to obtain euphoric high. Long term use causes opioid receptors to become less sensitive to both endogenous. The loss of opioid receptor activity also increases responses of dopamine neurons to cues associated with drug use. Chronic drug use can: loss of opioid signaling systems. Moral model = little empirical support (snap out of it!) Disease model = some individuals are more susceptible to drug abuse than others due to genetic or environmental factors. Physical dependence = drug use occurs to avoid withdrawal symptoms (chills, pain, dysphoria/bad mood) Positive reward model = drug use is driven by reinforcement. Changes in receptor expression thought to conribute to decreased effect of natural rewards. Chrnoic cannabis use = differences were reversible with abstinence (28 days)
