PSYC 200 Lecture Notes - Lecture 5: Hypnic Jerk, Sleep Spindle, Sleep Deprivation
14 Jun 2018
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PSYC 200 Chapter 5: State of Consciousness
States of Consciousness – The many Faces of Awareness
• Consciousness: All the sensations, perceptions, memories, and feelings you are aware of
in any instant
o Waking Consciousness: Normal, clear, organized, alert awareness
o Altered State of Consciousness (ASC): Awareness that is distinctly different in
quality or pattern from waking consciousness
The Need for Sleep
: Innate, biological rhythm
• Sleep Deprivation: Sleep loss; being deprived of needed amounts of sleep
• Sleep-Deprivation Psychosis: Confusion, disorientation, delusions, and hallucinations
that occur because of sleep loss (& can die)
• Unsure why sleep is so necessary
Game: scale/questionnaire to see how sleepy you are
Sleep Patterns
• Sleep Patterns: Daily rhythms of sleep and waking
• Short Sleeper: A person averaging 5 hours of sleep or less per night.
• Long Sleeper: A person who averages nine hours of sleep or more per night.
Measuring Sleep Changes
• Electroencephalograph (EEG): Device designed to detect, amplify, and record electrical
activity in the brain
• Beta Waves: Small fast waves associated with being AWAKE and alert
• Alpha Waves: Large, slow waves associated with relaxation and FALLING ASLEEP.
Stages of Sleep – NREM (identified by brain patterns/changes in behaviour)
• Stage 1: Small, irregular waves produced in light sleep (people may or may not say they
were asleep). Muscle relax which may trigger reflex muscle contraction called hypnic
jerk (some alpha waves)
• Stage 2: Getting to deeper sleep; sleep spindle (sharp spike/ distinctive bursts of brain-
wave activity) appear
• Stage 3: Getting into deeper sleep; Delta waves appear - very large and slow
• Stage 4: People reach deep sleep (deepest level of
normal sleep). Brain waves are almost (ONLY) pure Delta waves
2 Basic Kinds of Sleep
• Rapid Eye Movements (REM): Associated with DREAMING
o Also known as Paradoxical Sleep
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find more resources at oneclass.com
▪ Body is very still/paralyzed (except eyes), BUT brain is ACTIVE – scan on
brain appears as if awake
o Lack of muscle paralysis during REM sleep is called REM Behavioural Disorder
• Non-REM (NREM) Sleep: Occurs during stages 1, 2, 3, and 4; no rapid eye movement
occurs.
o Seems to help us recover from daily fatigue
o Dreaming occurs, just less exciting → less likely to remember
• Video: Oneirology – study of dreaming
o Difficult to study b/c subjective, we forget 95% of our dreams
o REM - Chemicals blocked (ex. norepinephrine, serotonin) → usles do’t oe
o Lucid dreaming – can make conscious decisions
o Dreams are epiphenomenon – accidental result of stuff going on in conscious
brain
▪ Others think dreams propose us for threats (simulate anxiety)
Insomnia
• Insomnia: Difficulty in getting to sleep/staying asleep
• In 1992, 20% Canadian adults reported frequent problems getting to sleep
• Number rose to 25% by 1998 (Stats Can)
• Sleeping pills exacerbate insomnia; cause decrease in REM and Stage 4 sleep and may
cause dependency → detrimental
Types & Causes of Insomnia
• Temporary Insomnia: Brief period of sleeplessness caused by worry, stress, and
excitement.
o Avoid fighting it – Ex. read a book util you’e stugglig to stay aake.
• Chronic Insomnia: Exists if sleeping troubles last for more 3+ weeks.
o Adopt regular schedule; Ex. go to bed at the same time each night
• Drug-Dependency Insomnia: Sleeplessness that follows withdrawal from sleeping pills
Sleepwalking and Sleeptalking
• Sleepwalking (Somnambulism): occurs in NREM sleep during Stages 3 and 4
• Sleeptalking: Speaking while asleep; occurs in NREM sleep during Stages 3 and 4
find more resources at oneclass.com
find more resources at oneclass.com
Sleepwalking – An Unusual Example
• Young Canadian man drove 23 km to in-las’ house, killed mother-in-law, viciously beat
up father-in-law and injured self in scuffle.
• Man subjected to intense medical and psychological examination.
• Defense argued attacks were not premeditated and occurred during episode of
nocturnal somnambulism, in state of unawareness.
• Verdict of not guilty upheld by Supreme Court
Sleep Apnea
: Repeated interruption of breathing during sleep.
• Breathing stops for periods of 20 seconds to two minutes.
• Apnea victims complain of hypersomnia (excessive daytime sleepiness).
o Hard to diagnose w/o study b/c only complaint is fatigue
• Causes: 2 types → 1. brain stops sending signals to diaphragm; 2. blockage of upper air
passages.
• Treatment: Weightloss, Mask to unblock upper air passage (CPAT machine)
Other Sleep Problems (in DSM)
• Hypersomnia: Excessive daytime sleepiness
• Narcolepsy: Sleep disorder that causes a person to suddenly slip directly into REM sleep
(lose control of body/paralysis)
• Video: Narcoleptic Poodle – triggered by emotions
Adolescent Sleep Epidemic
• Adolescent average sleep need:
o 9.2 hours
• Ages 13 to 19:
o 75% report a bedtime later than 11:00pm on school nights
• 2006 National Sleep Foundation (NSF) poll:
o Only 1/5 adolescents get an optimal 9hrs of sleep on school nights
• 2011 NSF poll:
o 7% of adolescents report sleeping <6hrs on weeknights
• Typical sleep pattern:
o Late bedtimes and early wake up time on weekdays
o Sleep in on the weekends, stay up late Sunday night,
but get up early on Monday morning
• 47.5% adolescent report being tired once per week
What causes adolescent sleep problems?
A. Extrinsic factors:
• Activities, employment, academic demands
o In drama till 10pm
find more resources at oneclass.com
find more resources at oneclass.com
