Hockenbury Discovering Psychology 5th txtbk

174 CHAPTER 4 Consciousness and Its Variationsstimulant-induced psychosisSchizophrenia-like symptoms that can occuras the result of prolonged amphetamine orcocaine use; also called amphetamineinducedpsychosis or cocaine-inducedpsychosis.psychedelic drugs(sy-kuh-DEL-ick) A category of psychoactivedrugs that create sensory and perceptualdistortions, alter mood, and affect thinking.mescaline(MESS-kuh-lin) A psychedelic drug derivedfrom the peyote cactus.LSDA synthetic psychedelic drug.How quickly cocaine’s psychological effects occur, and how long they last,depends on whether cocaine is snorted, swallowed, smoked, or injected. Crackcocaine, a more concentrated form of cocaine, is smoked. (The name crack refers tothe sound of the cocaine crystals popping and cracking when smoked.) Whensmoked or injected, cocaine reaches the brain in seconds and its effects peak inabout 5 minutes. When snorted, the nasal membranes absorb cocaine more slowly,with peak blood levels occurring some 30 to 60 minutes later.Chronic cocaine use produces a wide range of psychological disorders. Of particularnote, the prolonged use of amphetamines or cocaine can result in stimulantinducedpsychosis, also called amphetamine-induced psychosis or cocaine-induced psychosis.Schizophrenia-like symptoms develop, including auditory hallucinations ofvoices and bizarrely paranoid ideas. In response to imagined threats, the psychotic personcan become highly aggressive and dangerous.Psychedelic DrugsMescaline, LSD, and MarijuanaThe term psychedelic drug was coined in the 1950s to describe a group of drugsthat create profound perceptual distortions, alter mood, and affect thinking. Psychedelicliterally means “mind manifesting.”Peyote-Inspired Visions The Huichol Indiansof Mexico have used peyote in religious ceremoniesfor hundreds of years. Huichol yarnpaintings, like the one shown here, often depictimagery and scenes inspired by traditionalpeyote visions. These visions resemble thegeometric shapes and radiating patterns ofhallucinations induced by psychedelic drugs.Today, peyote continues to be used as asacrament in the religious ceremonies of theNative American Church, a religion withmore than 300,000 members (Swan & BigBow, 1995). According to one study, the useof peyote as a sacrament in the context ofchurch ritual was not associated with eitherpsychological or cognitive problems inNavajo members of the Native AmericanChurch (Halpern & others, 2005).Mescaline and LSDNaturally occurring psychedelic drugs have been used for thousands of years.Mescaline, which is derived from the peyote cactus, has been used for centuries inthe religious ceremonies of Mexican Indians. Another psychedelic drug, called psilocybin,is derived from Psilocybe mushrooms, which are sometimes referred to as“magic mushrooms” or “shrooms.” Psilocybin has been used since 500 B.C. in religiousrites in Mexico and Central America.In contrast to these naturally occurring psychedelics, LSD (lysergic aciddiethylamide) is a powerful psychedelic drug that was first synthesized in the late1930s. LSD is far more potent than mescaline or psilocybin. Just 25 micrograms, orone-millionth of an ounce, of LSD can produce profound psychological effects withrelatively few physiological changes.LSD and psilocybin are very similar chemically to the neurotransmitter serotonin,which is involved in regulating moods and sensations (see Chapter 2). LSD andpsilocybin mimic serotonin in the brain, stimulating serotonin receptor sites in thesomatosensory cortex (González-Maeso & others, 2007).The effects of a psychedelic experience vary greatly, depending on an individual’spersonality, current emotional state, surroundings, and the other people present.A “bad trip” can produce extreme anxiety,panic, and even psychotic episodes.Tolerance to psychedelic drugs may occurafter heavy use. However, even heavyusers of LSD do not develop physical dependence,nor do they experience withdrawalsymptoms if the drug is nottaken.Adverse reactions to LSD includeflashbacks (recurrences of the drug’s effects),depression, long-term psychologicalinstability, and prolonged psychoticreactions (Smith & Seymour, 1994). Ina psychologically unstable or susceptibleperson, even a single dose of LSD canprecipitate a psychotic reaction.