Chapter 5 - Consciousness Flashcards
Define: Consciousness
Our subjective experience of the world, our bodies, and our mental perspectives
Define: Circadian rhythm
Sleep/wakefulness cycle that follows “around a day”
Other biological activities that follow 24-hour cycle
Body temp; blood pressure; hormone levels
Body temps at what times?
36.1C at 4-5am; 37 at 4-8pm (“Wake up cold”)
Alertness decreases between what times?
2-5pm and 2-7am
Define: Ultradian rhythm and give examples
Occurs several times per day (hunger; urination)
Define: Infradian rhythm and give examples
Exceeds 24-hr pattern (menstruation)
Define: Suprachiasmic Nucleus (SCN)
Known as the biological clock
20000 nerves in hypothalamus
How much sleep do we need?
7-10h per day
Newborns need how much sleep?
> 16h per day
Four things sleep is critical for
- Immune system
- Memory consolidation
- Neuronal development
- Neuronal connectivity
Six effects of sleep deprivation
- Depression
- Difficulty learning
- Slowed reaction time
- Hallucinations
- Health problems (heart, BP, immune system, diabetes)
- Weight gain
Dr. Carney of Ryerson?
Found links between lack of sleep and obesity
Ways to improve sleep
- Pay attention to eat/drink (caffeine, alcohol)
- Limit naps
- Physical exercise
- Managing stress
- Pre-bed routine
- Focus on breathing
- Cool room
- Notepad to write down running thoughts
Sleep in predators vs prey
Predators sleep more than prey. Prey who can hide well sleep more.
Sleep in small vs large animals
Small body mass sleep more
Three hypotheses for why we sleep
- Repairing/restoring: repair wear and tear; neuronal development and increasing connections; immune system
- Survival value: Stopped early humans from going out during low light and at risk from predators
- Brains need REM sleep
Stages of sleep (non-REM)
Stage 1: Light sleep; theta waves; transition between sleep and waking; myoclonic jerks
Stage 2: Up to 65% of total night’s sleep; sleep spindles & K-complexes
Stage 3&4: Deep sleep; ~25% of sleep (40% in children); delta waves
Define: Sleep Spindles
Intense bursts of electrical activity; 12-14 per second (during stage 2)
Define: K-complexes
Sharply rising and falling waves (during stage 2)
Define: REM sleep
-Rapid Eye Movement; 20-25% total; “paradoxical” or “active” sleep
Physical markers of REM
Increased HR; darting closed eyes; paralysis; midde ear muscular activity (MEMA); surge in epinephrine and adrenaline
When does REM happen?
- At about 90 in into sleep cycle
- After 2 or 3 cycles, no more stage 4
- First REM is 10-15 min but gets progressively longer
- % REM stays same with age but quality and quantity changes (links to brain maturation)
Necessity of REM?
- Deprivation causes irritability, attention lapses, difficulty concentrating; death in rats
- Importance might be REM’s role in dreaming (80% awakened during REM reported dreaming)
Define: REM rebound
- Lost REM tends to be made up the next night
- May cause more nightmares
Freudian view of dreams
- “Wish fulfillment”
- Allow us to act on our wishes and desires
- Manifest content (actual details of dream) VS Latent content (true hidden meaning)
- BUT mostly rejected:
- Negative content is more common
- Sexual dreams are relatively rare
- Most dreams are straightforward, everyday
Define: Activation-Synthesis Hypothesis of Dreaming
- Surges of acetylcholine activate neurons on pons which turns on REM (triggering dreams)
- Meanwhile serotonin and norepinephrine shut down thereby decreasing attention cognitive reasoning.
- Forebrain attempts to make sense of the random patterns of activity
Damage to what part of brain can eliminate dreaming?
Forebrain, especially parietal lobe; even when pons is intact
Define: Neurocognitive Perspective on Dreaming
- Dreams are meaningful product of our cognitive capacities
- Dreams are fairly consistent over time so neurotransmitters and random neural impulses don’t tell the whole story
- Evidence from journal logs shows that dream contents are relevant to everyday issues
General consensus on Sleep & Dreaming:
-Acetylcholine triggers REM + Forebrain plays an important role
Dreams perform what higher functions?
PLIRP/ RIP LP
- Processing emotional exp
- Learning new strategies
- Integrating
- Reorganizing and consolidating
- Practice responses
Define: Insomnia
- Difficulty falling, staying asleep; restless, poor sleep
- Causes distress and daytime impairment
- Treat: change sleep environment and routine
Define: Narcolepsy
- Rapid and unexpected onset of sleep
- Sudden attacks of REM (10-20 min)
- Excessive daytime sleepiness
Define: Sleep apnea
- Periods when breathing stops and person is awakened to breathe
- Snoring and Excessive daytime sleepiness
- Being overweight
- Treat: CPAP (Continuous Positive Airway Pressure) machine
Define: Parasomnias
- Category of sleep disorders that happen during sleep or between stages
- Abnormal behaviour, movements, perception, etc
Define: Nightmare
- “Bad dream”
- Occurs toward morning, in REM
- Causes: sleep deprivation; drugs; stress
Define: Night Terror
- Mostly in children
- Awakening in extreme state of panic
- NREM sleep (esp. 3&4)
Define: Sleepwalking
- “Somnombulism”
- Mostly in children
- Rises and wanders during sleep
- NREM sleep (esp. 3&4)
Define: Psychoactive Drug
-A substance that affects behaviour and mental process through alteration of conscious awareness
Symptoms of Addiction to drug:
- Intense urge
- Having to take regularly
- Making sure to have steady supply
- Not meeting obligations
- Continuing use despite health, legal, financial, social problems
- Risky behaviour to obtain
- Failing attempts to stop
- Withdrawal symptoms
Define: Stimulant; and give examples
- Increase activity of CNS
- “Uppers”: increase BP, resp., and HR
- Caffeine; Nicotine; Cocaine; Methamphetamine; Adderal; Ritalin; Concerta; “Bath Salts”
How does nicotine work?
- Activates receptors sensitive to Acetylcholine, leading to relaxation and alertness
- Builds tolerance in hours
How does cocaine work?
- Blocks reuptake of Dopamine; stimulates reward or pleasure centres
- Drug of choice for animals addicted to multiple drugs
- Intense up and down
How do amphetamines work?
- Blocks reuptake of AND releases Dopamine in synaptic cleft
- “Superhuman” feelings; crawling sensations’ tooth decay
Define: Depressants; and give examples
- Slow down CNS activity
- Alcohol, Barbituates, Tranquilizers
How does alcohol work?
- Interacts with GABA and Glutamate neurotransmitters
- Affects the cerebellum, memory formation, impulse control
- Correlates with declines in IQ
- Causes alcohol hallucinations (auditory and paranoid)
What are some tranquilizers, and their consequences?
- Benzodiazepines (Valium, Xanax)
- Ketamine
- Excess use=temporary or permanent memory impairment
Define: Opiates and give examples
- Reduce pain, produce euphoria, calming effect, impaired concentration, constipation
- Releases dopamine; tolerance builds quickly
- Known as narcotics
- Opium, heroin, morphine, codeine, Oxycontin, Vicodin, Fentanyl
Define: Hallucinogens/Psychedelics and give examples
- Affect perception and distort reality
- Marijuana, LSD, MDMA
Discuss marijuana (components, effects)
- Tetrahydocannabinol: Pain reliever; anti-nausea; appetite stim; sleep aid
- Cannabidiol (CBD): Anti-inflammatory; anti-epileptic; anti-anxiety; anti-nausea
- Dry mouth; red eyes; impairs attention, coordination; memory, reaction time; sensitivity to sound and colour
- Chronic, early, and heavy use: associated with amotivational syndrome and impaired cognitive function
Marijuana onset, max effect, duration; inhaled and oral
- Inhaled: >15min; >15 min; 3-4 h
- Oral: 30-90min; 2-3 h; 4-8 h
Discuss LSD
- Lysergic acid diethylamide
- Kaleidoscope colours, mystical experiences
- Mimics and interferes with serotonin at synapse
Discuss MDMA
- Has both stimulant and hallucinogenic properties
- Releases serotonin
Define: Agonist
-Psychoactive drugs that increase neurotransmitter receptor site activity
Two drugs that are agonists and how they work
- THC has similar properties to Anandamine (involved with pain, depression, appetite, memory)
- Opiates act like Endorphins (euphoria, no pain, all good)
Two drugs that release neurotransmitters and/or block reuptake
- Cocaine blocks reuptake
- Amphetamines increase dopamine and block reuptake
Define: Nucleus Accumbens
-In limbic region; influenced by dopamine to play role in reward and reinforcement
Define: Physical dependence
-Caused by tolerance built as body’s natural protective mechanism
Define: Tolerance
-Reduction in effect of drug; need to consume more to have same effect
Define: Psychological dependence; how to treat
- Craving or urge for pleasurable effects
- Harder to combat than physical dependence
- Replace old behaviour with new one
Define: Withdrawal symptoms
- Both physical and psychological
- Usually exact opposite of effects of drug
- After ~2-3
- Delirium: disorientation, confusion, terrifying hallucinations
- Vomiting, sweating, etc
