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drugs

drugs. Controversy, danger, tradition. Controversy and confusion. Uneasy boundary between legal and illegal, beneficial and harmful Many legal drugs injure in high amounts Many are addictive Many illegal drugs have medical uses Gateway drugs?

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drugs

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  1. drugs Controversy, danger, tradition

  2. Controversy and confusion • Uneasy boundary between legal and illegal, beneficial and harmful • Many legal drugs injure in high amounts • Many are addictive • Many illegal drugs have medical uses • Gateway drugs? • Misinformation – often causes people to ignore real risks

  3. background • Humans use, and abuse, a wide variety of drugs which exert widely ranging effects • Genetics play a role in our differing sensitivities to drugs • Also, behavioral tendencies like impulsivity, novelty-seeking, hyperactivity, and variations in tolerance of stress, are important

  4. Focus on the brain • The release of dopamineand the pleasure which follows, tells us what we like • This nudges us into eating, drinking, and other beneficial behaviors • Years of research has revealed that ingesting many drugs also causes dopamine to be released, hi-jacking this natural reward system - to our peril

  5. Underlying neurology • The dopamine circuit begins in the ventral tegmental area (found at the top of the brain stem)which synthesizes dopamine which it passes to the • Nucleus accumbens which then connects through its axons to areas of the frontal lobes • Continued use of some drugs (opiates) causes neurons to shrink or otherwise work less effectively, forcing the user to rely on the drug for pleasure

  6. but there is more • Two other key brain structures are also involved • The amygdala adds an emotional overtone to the desire for this manipulation of the reward circuit • Even more importantly, the hippocampus makes sure that we remember the fun times associated with the drug, and the surroundings which accompany it

  7. perspectives • Many drugs decrease our ability to experience pleasure normally • We then need them to make-up for what they have taken from us • But these changes to our natural reward system can also be effected by other things such as gambling, video games, even sweets

  8. alcohol • World-wide and ancient use • Part of many of our customs and traditions • At the most basic level, simply a class of molecules • We are concerned with ethanol – the type which people drink

  9. Alcohol – the depressant that makes us act out • While we typically link drinking alcohol with wild, reckless behavior, it is actually a depressant • That’s because it, especially in high amounts, lessens our inhibitions by turning off our frontal lobes, increasing impulsivity/risk- taking behavior • Excessive use leads to physical damage

  10. tranquilizers • Another type of depressant • Help us relax, fall asleep and decrease muscle tension • Barbituratesformerly commonly prescribed, now out of favor – addiction and other risks • Benzodiazepines, such as valium, now hold sway – less addictive

  11. bennies • Great danger mixing them with alcohol • Both stimulate production of the neurotransmitter GABA, which can inhibit the function of the medulla disrupting our breathing and heartbeat – a truly fatal mix • Another aspect of these drugs is their use as “date rape” drugs – very inconspicuous • Flunitrazepam/Rohypnol, or “roofies” • Induce euphoria, lack of inhibitions, amnesia

  12. narcotics • Produce drowsiness, insensitivity to pain and indifference to events • Most commonly opiates • Natural substances derived from the opium poppy • Also synthetic compounds with similar chemical structures - methadone

  13. Opiates - why they wreak such havoc • Give users a warm, happy, contented feeling • Heroin, morphine, methadone (synthetic) • Virtually eliminate pain and anxiety but at the cost of apathy and fast addiction • When the unnatural production of dopamine ceases the body cries out for it • If denied, chemical withdrawal begins

  14. Withdrawal from opiates • During withdrawal all of the pleasant effects of the drug are reversed • While before there was contentment now there is anxiety, before happiness now pain • Worse yet, we need more - tolerance • Need for a “fix” causes desperate actions • theft, burglary, prostitution, shattered lives, criminal prosecution

  15. Long term effects • Longitudinal studies paint a very bleak picture • Of 581 users followed from 1962, nearly half were dead by 1997 • Survivors self-medicated, including cigarettes (67%) • They also faced many health problems, including hypertension, liver and lung ills, etc.

  16. stimulants • Drugs which boost energy, alertness, activity and pleasant feelings • Caffeine perhaps the most widely used drug? – 90%! • Delivered through coffee, chocolate, soda, energy drinks, tea • Can lead to dependency – headaches and drowsiness if denied

  17. cocaine • The drug of choice in the 80’s and beyond • Derived from the leaves of the coca plant • Creates a euphoric sense of happiness and increased activity • Considered a stimulant because it turns off inhibitors, leading to an increase in behaviors • But its use decreases over-all brain activity

  18. More cocaine • Very powerful, with many effects • Works by preventing a terminal button’s synaptic vesicles from reabsorbing dopamine (reuptake) thus increasing its effects • Also, kicks up norepinephrine and serotonin levels • Works as an anesthetic ( as does lidocaine and Novocain)by stopping action potentials

  19. Cocaine and addiction • Usually taken in powder form with euphoria coming on within minutes and lasting for up to an hour • If smoked through free basing, its effects emerge even faster • The faster the pleasure, the quicker the addiction

  20. Crack – addiction squared • Crack cocaine, first developed in the mid- 80’s, provides even quicker, virtually instantaneous, pleasure • Addictive after only a few uses • Very expensive, readily addictive and quick to lose its effects • It takes over lives, ruining careers and families

  21. Long term • While coke-triggered heart attacks and strokes strike occasionally, its residual damage is harder to assess • Many who started to use it in the 80’s are now well into their 50’s and the number of addicts over 50 is set to explode, perhaps to over 4 million • Effects are often worsened by overall neglect

  22. marijuana • CONTROVERSY • Intensifies sensory experiences, induces euphoria, distorts time perception, also can lead to feelings of anxiety • Formally known as Cannabis sativa • Main psychoactive chemical is called THC • Cultivated for at least 3000 years

  23. The neurochemistry of marijuana • Mimics a neurotransmitter called anandamide • They attach to receptors which affect short term memory (on the hippocampus) which can make it difficult to remember events and learn • Also they impact our muscle coordination by altering the normal functions of the cerebellum

  24. Medical benefits • Research shows that marijuana aids some medical conditions: Chemotherapy problems – decreases vomiting, nausea, and anxiety Aids-related wasting – improves appetite Pain and muscle spasms – decreases these plus depression Glaucoma – decreases pressure on eye

  25. Why pot? • It is so easy to administer • Puff by puff, the user can simply stop when acceptable levels have been reached • Low toxicity • Plus, its effects last no longer than 2 – 3 hours and no chance of overdose • But, since it is fat soluble, it can be detected for 28-30 days after ingestion

  26. The debate • Life threatening? • Harmless? • Probably neither. • A gateway drug? (millions spent) very few move on to cocaine or heroin most used tobacco and alcohol first if marijuana disappeared would cocaine and heroin?

  27. withdrawal • Is pot addictive? tolerance doesn’t seem to develop nothing compared to opiates, alcohol, or nicotine very little proof of any residual effects 99% discontinue use without any withdrawal effects

  28. Other risks • Evidence is building of a relationship between early pot use and the development of psychosis • Use before the age of 15 can make vulnerable teens much more likely to eventually develop serious mental illness • Genetic predispositions activated by environmental conditions

  29. A real danger? • Amotivational syndrome • Putting off important things till tomorrow because you got high today • Coupled with well established barriers to learning, pot smoking can cause people to waste a lot of time and money • Fact of fiction?

  30. Long term • A 2003 study stated that even among regular users there is no proof of irreversible cognitive damage • Uncertain as to long range pulmonary disease and cancers though pot does contain carcinogens

  31. hallucinogens • Drugs which induce sensory distortions • Can come from plants – mushrooms (psilocybin) or cactus (peyote) • Also produced synthetically – LSD • Famous for amazing intensification of sensations and experiences – from dream-like states to transcendent mystical events

  32. Mescaline and psilocybin • Mescaline, better known as peyote, isderived from a Chihuahan cactus found in Texas and Mexico • It has been used medicinally and sacramentally for thousands of years • US government allows its use in Native American religions • Initial focus of Carlos Castenada’s “quest”

  33. More peyote • Users consume it in buttons • Many initially experience nausea which is followed by feelings of physical energy (small doses) or visionary experiences which they view as a spiritual and physical blessing • A recent study of regular Native American users found no harmful cognitive or psychological effects, and some gains!

  34. Magic mushrooms • Psilocybin, an active chemical compound in hundreds of mushrooms that causes hallucinogenic experiences • Used world-wide especially by the Aztecs • Can be smoked or simply eaten • Castenada, and many others, sampled • Most common natural hallucinogenic

  35. lsd • Officially lysergic acid diethylamide • Accidentally discovered by a Swiss chemist, Albert Hoffman, in 1943 • Somehow ingesting it, he experienced an amazing shift in consciousness • “An uninterrupted stream of fantastic images of extraordinary vividness and plasticity” passed before his eyes “ accompanied by an intense kaleidoscopic play of colors”

  36. Further “research” • Hoffman went on to try LSD on many more occasions • These experiences were invariably pleasant except once, when tired, he mixed it with amphetamines and experienced history’s first “bad trip” • Recently turned 100, he still considers LSD “medicine for the soul”

  37. Then things got weird • The word slowly spread until in the early 60’s it reached Timothy Leary, a maverick Harvard psychologist with extensive work with psilocybin • Leary experimented with his graduate students and raved about LSD’s effects reporting profound mystical and spiritual experiences • “Turn on. Tune in. Drop out.” • “The most dangerous man in America.”?

  38. The serotonin connection • LSD attaches to receptors usually used by serotonin • It apparently stimulates the receptors in strange ways • Change our typical perceptual filtering? • Bad trips largely arise from the setting • In secure environments, very unlikely • Some suffer flashbacks, but still rare

  39. ecstasy • Also known as MDA or MDMA • Synthetic compounds which resemble neurotransmitters and stimulate serotonin receptors • Users report heightened intimacy and insight into relationships • Many negative effects – confusion, anxiety • Evidence points towards damage to axons devoted to serotonin

  40. Crystal meth • Also known as methamphetamine • Causes extensive production of dopamine • Ingestion leads to an almost instant tingly rush of sexiness, confidence and alertness • But eventually, dopamine receptors are depleted and users feel unable to experience pleasure without more and more

  41. A hurricane of shattered bodies and lives • Addiction often follows with devastated families, lost jobs, ruined health, crime, etc • Horrible physical aftermath – premature aging, skin sores, ruined teeth, wasting • Burns victims overwhelm rural counties $$ • But for the Bush administration pot is still enemy #1 – Local governments disagree

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