181) University students who are heavy users of marijuana show evidence of __________. A) long-term memory loss B) cognitive impairments C) serious medical illnesses D) depression 182) Research using animals has found some disturbing similarities between marijuana and such drugs as __________. A) cocaine B) inhalants C) nicotine D) LSD 183) For most adolescents, alcohol is used primarily to ________. A) be accepted by their peers B) prove they are adults C) get “high†D) avoid social anxiety 184) There appears to be a common pathway in the brain involving the neurotransmitter ________ that may explain the pleasure-inducing effects of many drugs. A) cortisol B) dopamine C) acetylcholine D) norepinephrine 185) Researchers suspect that drugs such as nicotine, alcohol, heroin, cocaine, and even marijuana produce pleasurable effects by increasing the levels of the neurotransmitter dopamine—the brain’s___________ agent. A) activation B) reward C) memory D) emotional 186) When the body becomes habituated to opiates, it ceases production of ________. A) testosterone B) endorphins C) prostaglandins D) norepinephrine 187) People who have close relatives who are dependent on alcohol are about ________ times more likely than others to become alcoholics themselves. A) one to two B) two to three C) three to four D) four to five 188) Twin studies have found ________. A) no significant correlation for rates of alcoholism in male monozygotic or dizygotic twins B) a greater concordance rate of alcoholism for male monozygotic twins than for dizygotic twins C) a greater concordance rate of alcoholism for dizygotic twins than for male monozygotic twins D) an equal concordance rate of alcoholism for male monozygotic and dizygotic twins 189) Twin studies have found that in regards to inheriting a risk for alcoholism, there is ________. A) no evidence of genetic factors involved in either males or females B) evidence of a stronger genetic component for males than for females C) evidence of a stronger genetic component for females than for males D) evidence of an equally strong genetic component for males and females 190) Research identifying a specific gene in the transmission of a vulnerability to alcoholism has led to speculation that the gene may disrupt the activity of ________ receptors in the brain. A) dopamine B) serotonin C) endorphin D) thyroxin