Brain State and Consciousness PDF
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This document provides information on brain states and consciousness, including the history of consciousness, elements of consciousness, forms of consciousness, cognitive neuroscience, sleep stages, age trends in sleep, sleep deprivation, sleep disorders, and the effects of drugs. It also covers circadian rhythms, disruptions to circadian rhythms, and issues like insomnia and sleep apnea.
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Brain State and Consciousness History of Consciousness - William James - Psychology began as a science of consciousness - Strualist; Introspection - Functionalist: stream of consciousness After 1960 Consciousness reentered psychology The Elements of Consciousness Awareness of - External ev...
Brain State and Consciousness History of Consciousness - William James - Psychology began as a science of consciousness - Strualist; Introspection - Functionalist: stream of consciousness After 1960 Consciousness reentered psychology The Elements of Consciousness Awareness of - External events - Internal sensation - Self as a unique being experiencing these events - Thoughts about the experience Forms of consciousness Consciousness; awareness of ourselves and our environment Some occur some are Some are spontaneously physiologically psychologically induced induced daydreaming hallucinations Sensory deprivation Drowsiness Orgasm Hypnosis dreaming food or oxygen mediation starvation Cognitive Neuroscience Emerges from the interaction of individual brain events like a chord Selective Attention - Inadttentional blindness = Failure to see visible objects when attention is directed elsewhere - Change blindness = failure to notice a change How much sleep do we need Significant biological funtion Most sleep > 175,000 hours in lifetime 70 million Americans: chronic sleep loss or sleep deprivation Current recommendations: 8 or more hours of sleep Facts about sleep: college students Most sleep deprived population - 7 hours sleep - 73% sleep problems 20-30% insomnia in past 3 months Sleep deprivation: lower GPA >30% report daytime sleepiness 69% feeling tired or having no energy Circadian Rhythms and Sleep - 24 hour biological cycle in everything humans to animals - Blood pressure, hormonal directions and body temperature - Includes sleep and wakefulness - Light triggers the suprachiasmatic nucleus to decrease melatonin from the pineal gland (morning) and increase (evening) it at night fall Disruptions to circadian rhythm - Sleeping at unusual time - Taking transcontinental flight = readjustment depends on directions flown Working night shifts - Reduced productivity - Accident proneness - Poor social relations - Reduced mental health Awake & Alert - Beta Waves: Low Amplitude, fast, irregular An Awaker person involved in a conservation Awake but relaxed stage - Alpha waves have large amplitude and slow and regular Eyes closed, but awake meditating Sleep stages every 90 minutes we pass through 5 cycles Sleep stages NREM 1-2 Brief and transitional Theta waves high amplitude slow and regular wave called - Breathing and heart rate slows, body temperature & muscle tension declines - Early light sleep - NREM1 = Hallucinations experienced Breif bursts of higher frequency brain waves Sleep stages 3-4 slow wave sleep Delta Waves; Large amplitude and low frequency - Breathing, heart rate, muscle tension, body temp continue to decline - Deepest sleep brain activity slows Stage 5 REM Sleep Beta Waves - Vivid dreaming - Irregular breathing pulse rate, muscle tone extremely relaxed (almost paralyzed); genital arousal - Deep sleep marked by rapid eye movements Age Trends in sleep Infants - 50% in infants vs 20% in adults in REM sleep Adults - REM sleep is constant - Slow wave sleep decrease - Stage 1 sleep increase - Average sleep time decreases How Sleep deprivation affects us - Brain = Decrease ability to focus, pay attention, memory, increased depression - Immune system = decreased production of immune, increase of viral infections flu - Heart = increased high blood pressure - Stomach = Increase in hunger and decrease hunger supression - Fat cells = increased production greater risk of obesity - Joints= increased infkammation and arthitis - Muscles = reduced strength, low reaction time and motor learning Why do we need REM and Slow-wave sleep - Is adaptive - Conserve energy - Reduce predator risk - Restores bodily resources - Consolidates memory - Failitates neurogenesis- forms new neurons - Increase creativity Sleep Disorder Insomina - Most common 30-35% of adults - More common in women - Chronic problem in getting adequate sleep - Diffucly in falling asleep, remaining asleep and persistent early-morning awakening Health problem - Impaired cognitive function - Increased risk for accidents - Decreased productivity - Depression - anxiety Causes - Excessive anxiety and tension - Other health problems Treatment - OTC sleeps aids - Benzodiazepene sedatives (Lunesta and Ambien) - Relaxation procedures - Melatonin supplements (NOT FDA regulated results are mixed) Sleep Apnea - Frequent reflexive gasing for air that disrupts sleep - Loud snoring: Irrtabilty: High blood pressure - Higher in men, postmenopausal women, older and obese adults Causes - Obesity - Smoking Treatments - Lifestyle changes (weight loss) - Drug therapy - Use of sleep apnea masks that open airway to improve airflow Night Terrors - Common in 3-8 years olds - Abrupt awakening from Non-REM sleep - Intense autonomic arousal and panic feelings - Increase in heart rate - Piercing cry, bolt upright and stare into space Treatment - Temporary problem Sleep Walking - Person arises and wanders about while remaining asleep - 3 hours of sleep during slow-wave sleep - Last 30 secs- 30 mins Causes - Unknown; maybe a genetic predisposition Narcolepsy - Gradual or sudden attacks of sleepiness (< 5 min) during the day - Occasional cataplexy - Muscle weakness while asleep - Sleep Paralysis - inability to move while falling asleep or waking up - Hypnagogic hallucinations - dreamlike experiences: trouble distinguishing from reality at the onset of sleep Treatments - Stimulates Some Natural sleep aids - Excerise - Avoid caffines - Relax before bedtime - Sleep on a regular basis - Hide the time - Tell yourself that tempoary sleep loss causes no great harm - Focus your mind on nonarousing, engaging thoughts like TV programs, song lyrics and vaction travel If all else fails settle for less sleep, either go to bed later or wake up earlier Dreams Content - Mundane - Familiar situations with friends, family members, colleagues - First person perspective Most common - Being chased - Sexual experiences - Falling - School studying - Arriving too late Why do we dream theories Freud Preserve Lacks scientific wish-fullfillmen sleep and evidence t provide a psychic safety value Information Help sort out Why do we dream processing our day events about the past or and things that we never consolidate experienced our memories Physiological Regular brain Does not explain Function stimulation why we experience from REM meaningful dreams sleep help develop and perverse neural pathways Neural REM causes Individual brain is Activation neural activity weaving the stories which evoke random visual Which tells us memories something about the which makes dreamer our brains weaves into stories Freud Preserve Lacks scientific wish-fullfillmen sleep and evidence t provide a psychic safety value Cognitive Content doesnt propose an development reflects adapative function dreamers level of our dreams of cognitive development, which makes Dreams stimulate our lives including worst case secnario Meditation Family of practices that train attention to heighten awareness and bring mental processes under voluntary control Lowers stress, anxiety, depression enhanced immune system, reduces drug abuses; controls blood pressure, improves cardiovascular health Drugs and Consciousness Psychoactive Drugs - Chemical substances that modify mental, emotional or behavioral functioning - 3 major classes Depressants Reduce arousal or stimulation by reducing neurotransmission Ex narcotics, sedatives, alcohol and tranquilizers Stimulants Temporarily improve mental or physical functioning Ex caffeine, nicotine and cocaine Hallucinogens Subjective alterations in perception, thought, mood and consciousness Ex LSD Dependence and Addiction Continued use of a psychoactive drug produces tolerance with repeated exposure to a drug the drug effect lessons thus, it takes greater quantities to get the desired effect Tolerance The need to take higher doses of a drug to achieve the desired effect because of the progressively reduced reaction to a specific drug dose Withdraw and Dependance - Withdrawal = Upon stopping the use of a drug (after addiction), users may experience the undesirable effects of withdrawal - Physical dependance = a person must continue to take the drug to avoid withdrawal - Psychological dependence = a person must continue to take the drug to satisfy intense mental and emotional craving for the drug Narcotics or Opiates Derived from Opium and capable of relieving pain Examples heroin, morphine, oxycodone - More than 300,000 americans abused heroin in the past year (nida.nih.gov) Mechanism of action - Bind to opioid receptors (pain perception and reward) Desired effects - Euphoria - Pain relief - Anxiety reduction Sedatives Decrease CNS activation and behavioral activity Ex barbiturates and non- barbiturates Desired effects - Induce sleep - Reduce anxiety Alcohol Variety of beverages containing ethyl alcohol Ex beers, wines, distilled liquors Desired effects - Relaxed euphoria - disinhibition Serious effect - Disrupt memory - Blackout’ - Reduces self awareness D on’t Underestimate Drunk Experiences Stimulants Drugs that increase CNS activation and behavioral activity - Caffeine nicotine, cocaine and amphetamines (meth) - Cocaine naturally grown - amphetamines synthesized in lab Mechanism of action Interferes with reuptake at dopamine and norepinephrine synapses Desired effects - Europhia - Alertness Hallucinogens Powerful effects on mental and emotional functioning marked by sensory and perceptual distortions Ex LSD, mescaline and cannabis Desired effects - Euphoria - Increased sensory awareness - Distorted sense of time Cannabis Hemp plant from which marijuana, hashish and THC are derived EX marijuana mixture of dried leaves, stems, flowers and seeds Desired effects - Mild relaxed euphoria - Increased sensory awareness Drug overdose - Many overdoses involve lethal combinations of CNS depressant Human Development Prenatal development 1. Germinal - 2 weeks - Zygote undergoes rapid cell division - Cells migrate to an implant on the uterine forming a placenta - Placenta Oxygen and nutrients from the bloodstream to fetus and bodily from fetus to mother 2. Embryonic = 2 weeks to 2 months - Embryo (1 in) - Vital organs (Heart, brain, spine) begin to form - Sensitive to structural defects and other complications - Most miscarriages occur at this time 3. Fetal = 2 months to Birth - Fetus - Skeletal, muscular systems mature - Organs grow and begin to function - Final 3 months - Brain cells multiply - Respiratory and digestive systems mature Environmental Factors Maternal Drug Use - Teratogens - external agents (drugs or virus) that can harm embryo or fetus - All recreational drugs (narcotics, sedatives cocaine) are harmful - Babies born with addiction to narcotics - Increased risk of early mortality due to birth defects and respiratory difficulties - Birth complications cognitive deficits - Alcohol consumption Fetal alcohol syndrome - collection of congenital problems associated with excessive alcohol use during pregnancy Caffeine - Crosses placenta - Higher amounts slightly increase risk of miscarriages, preterm births and low birth weight - 1-2 cups is not harmful Smoking during pregnancy - Fetal blood flow is reduced - Increased complications involving miscarriages, stillbirth, placental, abnormalities, growth retardation, preterm, low birth weight - Slower than average cognitive development, attention deficits, hyperactivity and conduct problems Maternal Nutrition and Emotions - Balanced diet - High in folate, vitamins, calcium, iron, sodium and zinc - Anxiety and depression can increase behavioral problems - Emotional responses to stress can disrupt hormonal balances necessary for optimal fetal development Infancy and childhood Physical development Brain cells are sculpted by heredity and experience - Birth = neuronal growth spurt - 3-6 months= rapid frontal lobe growth: continued growth into adolescence and beyond - Early childhood: critical period for some skills (language and vision) - Throughout life: learning changes brain tissues Motor development Motor skills - Develop as nervous system and muscles mature - Are primarily universal in sequence but not in timing - Are guided by genes and influenced by environment - Involve the same sequence throughout the world Walking In the U.S 25% walk by 11 months, 50% walk by 12 months. 90% walk by 15 months Novice walkers - Fell 32 times in average hour - Took 1500 steps per hour - Traveled three times distances as crawlers - Saw whole room Motor development = progression of muscular coordination required for physical activity - Cephalocaudal trend = Head to foot direction - Proximodistal trend = center outward direction It depends partly on physical growth and partly on maturation Maturation = development of that reflects gradual unfolding of one’s genetic blueprint Personality development Piaget theory - Understanding reasoning behind children’s wrong answers on intelligence tests - Interaction with the environment and First Sensorimotor stage (Birth to nearly 2 years) - Children coordinate sensory input with motor actions - Develop object permanence (4-8 months) - Awareness that things continue to exist even when not perceived Second Preoperational stage (2-7 years) - Centration- tend to focus on one feature of a problem ignoring the rest - Failure of conservation- awareness that physical quantities remain the same in spite of changes to shape and appearance - Egocentrism/curse of knowledge = cannot share another point of view Three Concrete Operational ( 7 to 11 years) - Think logically about concrete events - Begin to understand change in form before change in quantity and become able to understand simple math and conservation Four Formal Operational (12 throughout adulthood) - No longer limited to concrete reasoning behind on actual experience - Able to think abstractly Attachment close emotional bonds of affection that develop between infants and their caregivers 2-3 months old infants laugh and smile more interacting with their mother 6-8 months infants show a preference for mother and are resistant to strangers Strangers' anxiety = emotional distress are seen in infants when separated from people whom they formed an attachment Theories of attachment = Harlow - Infant monkeys raised with substitute mothers (terry cloth or wire) - Half fed by cloth mother and other half wire mother - Tested attachment by exposing monkey to fearful stimulus - Frightened monkeys clung to cloth mothers that provided contact comfort but have never fed them - Supported an evolutionary theory of attachment - Infants emit unlearned behaviors (smiling cooing) that trigger parental love and comfort Social development Attachment pattern - Strange situations procedure = infants are exposed to a series of eight separation and reunion episodes to assess attachment quality - Secure (60%): Play comfortably with mothers become upset when she leaves and calms down and seeks comfort when she returns - Anxious ambivalent attachment: Anxious in presence of mother protest when she leaves but not comforted when she returns - Avoidant/Insecure: seek little contact with mother and not distressed when she leaves Dependent on maternal sensitivity and children’s temperament - Mothers who are more responsive to children’s needs develop more secure attachment - Temperamentally difficult children develop slower secure attachment to mothers Effects of it quality of child's development - Infant are more resilient, secure and sociable - Preschool children: display more persistence, curiosity, leadership - Middle childhood: positive moods and healthier strategies for coping with stress - More advanced cognitive development Deprivation of attachment - 250 children had lower intelligence score and double the 20 percent of anxiety symptoms because of the romanian dictator assassinated Adolescence Puberty - sexual functions reach maturity - Primary sex characteristics develop - Female menarche - Male sperm production - Secondary sex characteristics develop - Synaptic pruning of unused neurons - Frontal lobe continues to develop Moral Reasoning Lawrence Kohlberg Devised a stage theory of moral development based on subjects Preconventional, Conventional, Postconventional Pre-law Law Post Law Preconventional = acts are considered wrong or right based on whether or not they are punished by them Conventional = Children sees rules as necessary for maintaining social order Postconventional = Personal code of ethics acceptance of rules are less rigid Adulthood Distinct new transitional life stage (18-25 years) - Not yet assuming adult responsibilities and independency - Feeling of being “in between” - May involve living with and still being with emotionally dependant on parents - Found mostly on contemporary Western culture - Delaying marriage and parenthood until late 20’s and early 30’s - Staying in school for long periods of time Early adulthood Muscular strength, reaction time, sensory keenes and cardiac output peak in mid twenties Middle adulthood - Physical vigor linked to health and exercise than age - Gradual decline in fertility - Female: menopause - Men: gradual decline in sperm count, testosterone, erection and ejaculation speed Late adulthood - Life expectancy worldwide increased from 46.5 to 70 years old - Visual sharpness, distance perception and stamina diminish - Pupils shrink and become less transparent - Immune system weakens and susceptibility to life threatening disease increase - Neural processing lag occurs; brain regions related to memory begins to atrophy; speech slows Neurocognitive disorders (NCD) and alzheimer's disease - Acquired (not lifelong) disorders;cognitive deficits Often related to alzheimer's disease, brain injury or disease or substance abuse - Erosion of mental abilities not typical of normal aging Alzheimer’s disease - Neural Plaques, often with an onset after age 80 - Progressive decline in memory and other cognitive abilities Neurocognitive disorders and Alzheimer's disease Step 1 Early adulthood Intimacy vs isolation Stage 2 Middle Adulthood Generativity versus self-absorption Stage 3 late adulthood Integrity versus despair Grief is severe Unconfirmed beliefs