Slide 1ToleranceWithdrawalDependenceDependence on a substance (or activity?)DepressantsEffects of Alcohol UseBarbituratesOpiates (Narcotics) Highly Addictive DepressantsStimulantsCaffeineNicotineCocaineMethamphetamineEcstasy/MDMA (MethyleneDioxyMethAmphetamine)HallucinogensSlide 17Slide 18Altering Consciousness DrugsPsychoactive drugs are chemicals introduced into the body which alter perceptions, mood, and other elements of An addiction is compulsively craving and using a drug, despite negative consequences.Diminished psychoactive effects after repeated use. Tolerance feeds addiction because users take increasing amounts of a drug to get the desired effect.ToleranceWithdrawalAfter the benefits of a substance wear off, drug users may experience withdrawal (painful symptoms of the body readjusting to the absence of the drug).Withdrawal worsens addiction because users want to resume taking the drug to end withdrawal symptomsDependence In physical dependence,the body has been altered in ways that create cravings for the drug (e.g. to end withdrawal symptoms). In psychological dependence,a person’s resources for coping with daily life wither as a drug becomes “needed” to relax, socialize, or sleep.Dependence on a substance (or activity?)Tolerance: the need to use more to receive the desired effectWithdrawal: the distress experienced when the “high” subsidesUsing more than intendedPersistent, failed attempts to regulate useMuch time spent preoccupied with the substance, obtaining it, and recoveringImportant activities reduced because of useContinued use despite aversive consequencesDepressantsExamples:alcoholbarbituratesopiatesChemicals that reduce neural activity (especially CNS) and other body functions.Effects of Alcohol UseImpact on functioning Slow neural processing,reduced sympathetic nervous system activity, and slower thought and physical reactionReduced memory formation,caused by disrupted REM sleep and reduced synapse formationImpaired self-control,impaired judgment, self-monitoring, and inhibition; increased accidents and aggressionChronic Use: Brain damageBarbiturates Barbiturates are tranquilizers– drugs that depress central nervous system activity.Examples: Nembutal, Seconal, AmytalEffects: reducing anxiety and inducing sleep Problems: reducing memory, judgment, and concentration; can lead to death if combined with alcoholOpiates (Narcotics) Highly Addictive DepressantsOpiates depress nervous system activity; this reduces anxiety, and especially reduces pain.High doses of opiates produce euphoria Opiates work at receptor sites for the body’s natural pain reducers (endorphins) Opiates are chemicals such as morphine and heroin that are made from the opium poppy.StimulantsExamples of stimulants:CaffeineNicotineAmphetamines, MethamphetamineCocaineEcstasySome physical effects of stimulants: dilated pupils, increased breathing and heart rate, increased blood sugar, decreased appetiteDrugs which intensify neural activity and bodily functionsCaffeineAdds energy  disrupts sleep for 3-4 hourscan lead to withdrawal symptoms if used daily:headachesirritabilityfatiguedifficulty concentratingdepressionNicotineReleases neurotransmittersEpinephrine & Norepinephrinediminish appetite and boosts alertness and mental efficiencyDopamine & Opioids calm anxiety and reduce sensitivity to painThe main effect of nicotine use is ADDICTIONCocaineCocaine blocks reuptake (and thus increases levels at the synapse of:Dopamine (feels rewardind)Seratonin (lifts mood)Norepinephrine (provides energy)Effect on consciousness: Euphoria!!! At least for 45 minutes…What happens next?Euphoria crashes into a state worse than before taking the drug, with agitation, depression, and pain.Users develop tolerance; over time, withdrawal symptoms of cocaine use get worse, and users take more just to feel normal.Cycles of overdose and withdrawal can sometimes bring convulsions, violence, heart attack, and death.MethamphetamineMethamphetamine triggers the sustained release of dopamine, sometimes leading to eight hours of euphoria and energy.What happens next: irritability, insomnia, seizures, hypertension, violence, depression“Meth” addiction can become all-consuming. The brain on meth may lose ability to maintain normal levels of dopamine, perhaps permanently.Ecstasy/MDMA(MethyleneDioxyMethAmphetamine)Ecstasy is a synthetic stimulant that Effects on consciousness: euphoria, CNS stimulation, hallucinations, and artificial feeling of social connectedness and intimacyWhat Happens Next?In the short run, Make it past that, and you might have:damaged serotonin-producing neurons, causing permanently depressed mooddisrupted sleep and circadian rhythmimpaired memory and slowed thinkingsuppressed immune systemHallucinogensLSD (lysergic acid diethylamide) LSD and similar drugs interfere with Drugs that alter sensation and perception and often causes hallucinationsMarijuana/THC (delta-9-TetraHydroCannabinol)Marijuana binds with brain Effect on consciousness:amplifies sensations disinhibits impulseseuphoric moodlack of ability to sense satietyMarijuana/THC: What Happens Next?Impaired motor coordination, perceptual ability, and reaction timeTHC accumulates in the body, increasing the effects of next useOver time, the brain shrinks in areas processing memory and emotion Controversies in Drug and Addiction ResearchThough many adverse effects, some drugs have been found Coffee (in moderation) has been linked to better memory, and decreased risk of cancer and diabetes Nicotine boosts learning and memory performance, and has been linked to decreased risk of Alzheimer’s and Parkinson'sSome researchers have claimed that the cause of addiction may not be In rat research, when rats have been continuously exposed to “addictive” drugs, when placed in an isolated environment, they choose drugged water over regular water. When placed in stimulating environment, they don’t When given choices between low doses of drugs and money, adults will choose money over