Topic 5: Consciousness PDF

Topic 5: Consciousness Encounters ~ 20% of college students endorsed belief that aliens communicate with us through dreams ~ 10% of people claim to have experienced or met an alien Some individuals even report alien abductions — why? Sleep paralysis Wake up or going into/coming o...

Topic 5: Consciousness Encounters ~ 20% of college students endorsed belief that aliens communicate with us through dreams ~ 10% of people claim to have experienced or met an alien Some individuals even report alien abductions — why? Sleep paralysis Wake up or going into/coming out of REM Feeling of being conscious but unable to move anxiety/terror, feeling of menacing presence Intruder/Vestibular-Motor/Chest pressure hallucinations Culture plays a role Culture & sleep paralysis (top-down influences on experience) Consciousness Our subjective experience of the world, our bodies, and our mental perspectives (waking consciousness) Altered states of consciousness: sleep paralysis, locked-in syndrome, out-of-body, near-death, mystical experiences, hypnosis, meditation, psychoactive drugs What is sleep? Low physical activity and reduced sense of awareness Associated with secretion of many hormones including: Melatonin Follicle stimulating hormone Luteinizing hormone Growth hormone Stages of sleep 5 stages of sleep in 90-minute cycles Stages 1 to 4 NREM No eye movements, fewer dreams Stage 5 REM sleep Vivid dreams and quick eye movements Sleep stages: overview Light sleep Deep sleep Heart rate decrease Brain erupts with powerful brain Body temp drops waves Electric brain wave activity slows Body is recharged Immune & cardiovascular benefits Memory consolidation Hypnagogic state: pre-sleep consciousness Hypnagogic imagery Visual Somatic Auditory Myoclonic/hypnic jerk Stage 1: Transition Transition from wakefulness and sleep Lasts only a few minutes Brain waves slow down Dreams like photos Stage 2: Falling asleep Further slowing of brain waves Sleep spindles and K-complexes As much as 65% of total sleep Stage 3 and 4: Deep sleep Delta waves 1st stage of deep sleep Crucial to feel rested Growth hormone production Children spend more time in NREM3/4 (efficient sleepers) than elderly Suppressed by alcohol  Stage 5: REM Sleep Rapid eye movement sleep Brain waves similar to wakefulness Paradoxical sleep — brain is very Antonia (cannot move) active, body is not Eye & inner ear movements REM rebound Probably essential WHY DO WE SLEEP? Sleep is adaptive Sleep is essential! (evolutionary perspective) Necessary for growth & brain Restore resources development Predatory risks BUT we are vulnerable during sleep BUT … we don’t really know why! Sleep is restorative! Sleep restores & replenishes us Memory consolidation, learning, cognitive function Slow-wave sleep Sleep needs People sleep approx. 7-8 hours a night Wide variability in sleep needs Sleep requirements vary over a lifetime Less sleep as we age  Sleep deprivation & mental health Sleep deprived people feel increased stress Tendency to overreact emotionally Lack of emotional regulation – has a biological basis React to neutral images as if they were emotional (amygdala activation, not connecting to frontal cortex) Peter Tripp: an extreme case of sleep deprivation Staged a “wakeathon” Broadcasted from Times Square for 200 hours Slurred speech, incoherent comments, visual hallucination – paranoia, delusion Family and friends reported personality changes Died at 73 of a stroke Sleep deprivation amongst post-secondary students Sleep hygiene: Regular sleep-wake schedule Quiet sleep environment Avoiding caffeine after lunch Avoiding stimulating activities before bed Don’t stay in bed if you’re not tired Don’t use your bed as an all-purpose area  Biological rhythm that occurs over 24 hours Regulated by suprachiasmatic nucleus (SCN) or biological clock of the Circadian hypothalamus Sleep-wake cycle, one of our main rhythm circadian rhythms is linked to our environment’s natural light-dark cycle Body temp, hormone production & blood pressure follow circadian rhythms THE SUPRACHIASMATIC NUCLEUS (SCN) SCN: brain’s clock mechanism. Sets itself with light information received through projections from the retina, allowing it to Figure 4.3 synchronize with the outside world. Melatonin & sleep regulation Sleep-wake cycle is also regulated by other factors Melatonin release stimulated by darkness, inhibited by daylight Makes us sleepy Released by the pineal gland  Disruptions of normal sleep Jet lag – symptoms resulting from mismatch b/w our internal circadian cycles and our env’t (fatigue, sluggishness, irritability) Rotating shift work – work schedule that changes from early to late on a daily/weekly basis difficult to maintain normal circadian rhythm Exhaustion, agitation, sleep problems, depression & anxiety Bright light can be used to realign biological clock with external env’t! Shift work ages the brain, dulls intellect Shift work aged the brain by more than 6 years Substantial decline in brain function associated with shift work Lower score for memory, speed of processing information and overall brain power Reversible! ~ 5 years to recover Safety consequences for the individual? For society? Marquie at al., 2014 Daylight savings time & car accidents  Dreams What is the function & meaning of dreams? Why do we dream? According to Freud: Dreams as unconscious wish fulfillment Latent vs. manifest content (what we really want vs. the story line we get) BUT… what about bad dreams? Sex dreams only 10%  Symbol versus interpretation According to Freud… what do you think these ‘symbols’ represented? Why do we dream? According to evolution… Dreams-for-survival theory Many dreams are stressful! Dreams represent concerns about our daily life, consistent with everyday living Information that is critical for our daily survival is reconsidered and reprocessed – so we can process information 24/7 Kurdish vs. Finnish children study – Kurdish children had more intense & frequent threatening dream events Why do we dream? According to neuroscience… Activation-synthesis theory Dreams are a way to make sense of random brain activity while sleeping Scenario isn’t random – clue to dreamer’s fears, emotions, concerns Motivational & emotional centres (e.g., limbic system) active during REM – less activation of PFC Sleep disorders: Insomnia Difficulty falling or staying asleep for at least 3 nights a week, for at least 1 month 9-20% of ppl experience insomnia Higher likelihood of insomnia amongst students (~25%): ADHD (3.48 times higher risk) Depression Employment Treatment: psychotherapy and/or hypnotic (e.g., Lunesta, Ambien) Concern about tolerance & side effects Paradoxical insomnia: I’m awake… or am I? Sleep-state misperception Sleep disorder where people believe they are sleep deprived despite having a normal sleep cycle Experience distress, anxiety & fatigue Cause is unclear – brain activity indicative of arousal during sleep Irrational beliefs & excessive worry Sleep disorders: night terrors & sleep apnea Night terrors: sudden waking episodes characterized by screaming, sweating and confusion – followed by return to deep sleep Most common in children (3-8), harmless Sleep apnea: blockage of the airway during sleep SIDS Sleep disorders: Narcolepsy Rapid and unexpected onset of sleep Directly into REM sleep Cataplexy Affects humans and animals Associated with lack of orexin Other sleep disorders REM behaviour disorder: Not paralyzed during & can act out dreams Somnambulism: Walking while fully asleep Vague consciousness of world around them Stage 3 sleep Perfectly safe to wake! Sleep deprivation & technology National sleep foundation poll (2014): Children with mobile device in room: 7.4 hours sleep per night Children without mobile device in room: 8.3 hours How is technology related to sleep loss? 1) person awakens intermittently 2) light exposure Psychoactive drugs Highs & lows of consciousness Psychoactive drugs % of Cdns who reported using Substances that contain drugs in past year (2019) chemicals similar to those 90 found naturally in brain that 80 altering biochemistry 70 (neurotransmission) 60 Influence emotions, 50 perceptions, behaviours – can 40 create dependence 30 20 Caffeine (stimulant), nicotine 10 (stimulant), alcohol 0 Alcohol Cannabis Cigarettes Illegal drug (depressant) & THC (stim & dep) Psychoactive Drugs Affect the nervous system in different ways Some alter limbic system Some alter neurotransmission Recap agonist, antagonist, reuptake Addiction & dependence Biologically based addiction Body becomes so accustomed to functioning in the presence of a drug it cannot function in its absence Psychologically based addiction People believe they need the drug to respond to the stresses of daily living Tolerance means more needed to achieve effect Physical dependence is related to withdrawal whereas psychological dependence is related to cravings Stimulants Drugs that have an arousal effect on CNS – rise in blood pressure, heart rate, and muscular tension Caffeine: increase in attentiveness, decrease in reaction time – improvement in mood (adenosine) Nicotine: activates neural mechanisms similar to cocaine Enhances norepinephrine & acetylcholine, promotes dopamine activates SNS Stimulants Amphetamines Strong stimulants like Dexedrine & Benzedrine (speed) Small doses – sense of energy, talkativeness, heightened confidence, increase concentration, This composite MRI brain scan illustrates that deficits in grey matter (indicated in red) reduced fatigue, mood ”high” in long-term methamphetamine abusers are particularly pronounced in an area around Prolonged use – paranoia, the corpus callosum. The volume of grey matter is more than 10% reduction in sexual desire –Large lower in users than non-users. doses can result in convulsion & death Amphetamines & ADHD E.g., Adderall,Vyvanse ADHD associated with lower levels of dopamine, seek stimulation Drugs like Adderall increase levels of dopamine, serotonin, & norepinephrine No ADHD à euphoria, increased wakefulness, better ability to cope with stress Cocaine Small doses produce feelings of profound psychological well- being, awake and energetic, increased confidence, less hunger/sleepy Larger doses: anger, violence, irritability, etc. Fidgeting (dopamine) “Highs” due to dopamine (blocks reabsorption) – floods the brain Depressants Downers” Slow down CNS – neurons fire more slowly Typically increase GABA activity Small doses: temporary feelings of intoxication along with euphoria & joy Large doses: speech becomes slurred, muscle control becomes disjointed, making motion difficult Heavy users may lose consciousness entirely  Alcohol Most commonly used depressant Stimulating at low doses (via dopamine),, euphoric, depressant effects kick in with higher doses Lowers inhibition, “social lubricant” , impairs judgment Magnifies emotions Females experience effects more heavily (same weight, higher BAC) Balanced-placebo design What we expect to happen plays a role in social behaviour Disentangle physiological effects from influence of expectation Placebo drinkers behaviour similar to alcohol drinkers Expectations more important than physiological in influences social behaviours (e.g., aggression)  Your brain on alcohol blurred vision (occipital), slurred speech and hearing (temporal), lack of control (frontal), may need help behaviour and judgement slightly walking or standing, blackouts coma risk, compromised altered, not obvious (hippocampus not working well) respiration and circulation 0.03 – 0.12 0.25 0.45 0.01 – 0.05 0.09 – 0.25 0.35 brain releases dopamine, euphoric, alcohol poisoning, senses severely relaxed, confident “tipsy” impaired alcohol poisoning may cause death A visit to the virtual bar… Depressants Barbituates prescribes to induce sleep or reduce stress (produce sense of relaxation) Psychologically & physically addictive With alcohol: relaxes muscles of the diaphragm to such an extent that user stops breathing (deadly) Benzodiazepines prescribed to treat anxiety & panic Highly addictive Excessive use can lead to tolerance (also memory impairment) Deadly with alcohol Quaaludes Methaqualone (brand name Quaaludes) CNS depressant – sedative & hypnotic (increases GABA) Popular in 1970s – taken so commonly as a recreational drug that it has been banned for 30 years Bill Cosby Narcotics Drugs that increase relaxation & relieve pain and anxiety Highly addictive E.g., heroine & morphine – derived from poppy seed pods Medical to abuse pipeline Opioids: poppy-seed derivates Morphine, heroin, codeine, oxycodone, hydrocodone, fentanyl CNS depressant – drowsiness, drift in & out of consciousness (nod off), binds to opioid receptors – dopamine agonist Euphoria & relaxation, blur boundaries between wakefulness & dream-like consciousness Reduced pain awareness (blocks pain messages) Depress respiration Tolerance à less responsive opioid receptors/decrease # of receptors Hallucinogens (psychedelics) Capable of producing hallucinations or changes in perception LSD, psilocybin, ayahuasca, marijuana, ecstasy, salvia (was legal until 2016!) Interest in therapeutic value Mystical experiences Treatment-resistant challenges MDMA & LSD MDMA & lysergic acid diethylamine (LSD, acid) – work primarily on serotonin, alter perception Ecstasy: users report peacefulness & calm, increased empathy & connection, relaxed but energetic LSD produces vivid hallucinations (can be wondrous or terrifying) Alteration in sensory perception & This drawing, made by someone taking LSD, suggests the effects of hallucinogens on thinking. distortions in time  Marijuana - THC (tetrahydrocannabinol) Effects are a mix of excitatory, depressive, and mildly hallucinatory Trigger spontaneous, unrelated ideas, distorted perceptions of time & place, increased sensitivity to sounds, tastes, and colours – erratic verbal behaviour Memory impairment, “spaced out” Cannabinoid receptors abundant in hippocampus – impairs memory consolidation Marijuana Prolonged cannabis use: Impaired cognitive function (reversible) Reduced dopaminergic function Cannabis-induced psychosis Hallucinations, delusions, disorganized thinking, paranoia (like schizophrenia) Kristen Gilliland holds a picture of Risks: high THC content, frequency of use, age her son, Anders, who died from an of first use, family history of mental health accidental overdose after being Not well understood but linked to dopamine diagnosed schizophrenia brought on release by cannabis-induced psychosis. Can last a few hours to long-term (cannabis- induced psychotic disorder)