Sleep.ppt

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Variations

in

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What is consciousness?



_{Awareness of ourselves and our}

environment.

– _{Count the passes}_and_{change blindness}_,_again

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So… why study consciousness?



_{Our consciousness is always changing for}

various reasons



_{How and why does conscious vary?}

– _{Biological rhythms}_{Biological rhythms} – Sleep and dreams_{Sleep and dreams} – Hypnosis_Hypnosis

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States of

Consciousness:

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Key Questions: Sleep



_{How do biological rhythms shape our}

consciousness and daily functioning?



_{Why do psychologists study sleep?}



_{What are the stages of sleep that we go}

through every night?



_{Why do we sleep? What happens if we do}

not get enough sleep?

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The National Sleep IQ Test

1. During sleep, your brain rests.

2. You cannot learn to function normally with one or two fewer hours of sleep than you need.

3. Boredom makes you feel sleepy, even if you have had enough sleep.

4. Resting in bed with your eyes closed cannot satisfy your body’s need for sleep.

5. Snoring is not harmful as long as it doesn’t disturb others or wake you up.

6. Everyone dreams nightly.

7. The older you get, the fewer hours of sleep you need. 8. Most people don’t know when they are sleepy.

9. Raising the volume of your radio will help you stay awake while driving.

10.Sleep disorders are mainly due to worry or psychological problems.

11.The human body never adjusts to night shift work.

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

_{Variations in}

consciousness are

shaped by

biological

rhythms

– Controlled by “biological _{Controlled by “biological} clocks” (internal chemical clocks” (internal chemical units that control regular units that control regular cycles in the body)

cycles in the body)

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

_{Types of cycles/rhythms}

– Circadian Rhythm_{Circadian Rhythm} –24-hour –24-hour cycles of varying alertness cycles of varying alertness

(sleep), body temperature, and (sleep), body temperature, and

growth growth

 Disruptions: jet lag and shift _{Disruptions: jet lag and shift}

rotations

 What about naps?_{What about}

– _{Ninety-minute cycles:}_{Ninety-minute cycles:}_{We go}_{We go} through various stages of sleep through various stages of sleep

in 90-minute cycles. in 90-minute cycles.

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Sleep: A State of

Consciousness

 Sleep and wakefulness _{Sleep and wakefulness} are influenced by our are influenced by our

circadian rhythms circadian rhythms

 Sleepers experience _{Sleepers experience}

considerable mental and considerable mental and

physical activity physical activity

throughout the night throughout the night

 About every 90 minutes _{About every 90 minutes} we pass through a cycle we pass through a cycle

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The Stages of Sleep

 Stages 1-4 = Non-REM Sleep (NREM) _{Stages 1-4 = Non-REM Sleep (NREM)}– No rapid – No rapid eye movement

eye movement

 Stages 1-2: Early light sleep; theta waves. _{Stages 1-2: Early light sleep; theta waves.}

– A person daydreaming also shows theta activity._{A person daydreaming also shows theta activity.} – Hypnic jerks and sleep spindles_{Hypnic jerks and sleep spindles}

– Lasts 10-30 minutes_{Lasts 10-30 minutes}

 Stages 3-4: Deep sleep starts_{Stages 3-4:}

– heart rate & blood pressure decline – some non-vivid dreams

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The Stages of Sleep



_{Stage 5: REM Sleep}

_{Rapid eye movement,}

occurs during dreaming



_{Characteristics}

– _{occurs every 90 minutes (on avg) in humans}_{occurs every 90 minutes (on avg) in humans} – increases in length as night progresses_{increases in length as night progresses}

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Sleep Deprivation



_{What is the purpose of sleep?}

– Recuperation, remembering, growing_{Recuperation, remembering, growing}



_{What happens if we don’t}

sleep?

– Fatigue _Fatigue

– Impaired concentration._{Impaired concentration.} – Emotional irritability._{Emotional irritability.}

– Depressed immune system._{Depressed immune system.} – Hallucinations and paranoia_{Hallucinations and paranoia}

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Sleep Deprivation



_{Study of}

_{sleep deprivation}

in college students

(Pilcher & (Pilcher & Walters, 1997)

Walters, 1997)

– Participants complete cognitive _{Participants complete cognitive} test after either 8 hours of sleep test after either 8 hours of sleep

or 24 hour sleep deprivation or 24 hour sleep deprivation

– All subjects asked to rate their _{All subjects asked to rate their} effort, concentration, and

effort, concentration, and

estimated performance on the estimated performance on the

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Sleep Deprivation



_{Results of college student}

study:

– Sleep deprived subjects _{Sleep deprived subjects}

performed worse than those who performed worse than those who

received 8 hours sleep received 8 hours sleep

– Although sleep deprived subjects _{Although sleep deprived subjects} performed

performed worseworse on the task, they on the task, they rated their own effort,

rated their own effort,

concentration, and performance concentration, and performance

higher

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 23% of individuals have fallen asleep while driving _{23% of individuals have fallen asleep while driving}

 59% of train engineers have fallen asleep on duty_{59% of train engineers have fallen asleep on duty}

 Airline pilots fall asleep in the cockpit (while flying) an _{Airline pilots fall asleep in the cockpit (while flying) an}

average of 32 times per month (1986 study)

 Nuclear disasters at Three Mile Island & Chernobyl, Crash _{Nuclear disasters at Three Mile Island & Chernobyl, Crash}

of Exxon Valdez all blamed on part in lack of sleep

 Estimation - accidents due to sleep deprivation cost the _{Estimation - accidents due to sleep deprivation cost the}

U.S. economy:

– $56 billion per year_{$56 billion per year}

– 52 million work days per year_{52 million work days per year}

– 24,000 deaths per year _{24,000 deaths per year} (Coren, 1996) (Coren, 1996)

Sleep Deprivation (Continued)

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Sleep Disorders

 Narcolepsy – disease marked by sudden – disease marked by sudden and irresistible onsets of sleep during

and irresistible onsets of sleep during normal waking periods

normal waking periods

– wakefulness to REM sleep for about 10-20 _{wakefulness to REM sleep for about 10-20}

minutes

– cause unknown_{cause unknown}

 Sleep apnea_{Sleep apnea} – frequent, temporary halt of – frequent, temporary halt of breathing for 15-60 seconds while sleeping breathing for 15-60 seconds while sleeping

– prevalent in 5% men 40-60 yrs old_{prevalent in 5% men 40-60 yrs old}

– _{CNS ceases to function, causing diaphragm to}_{CNS ceases to function, causing diaphragm to}

stop moving or loss of muscle tone in tongue

and throat

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Sleep Disorders



Insomnia

_Insomnia

:

– difficulty falling asleep, remaining asleep and persistent _{difficulty falling asleep, remaining asleep and persistent}

early-morning wakening

 Prevalence:_Prevalence:

– 15% adults report severe insomnia_{15% adults report severe insomnia} – 15% adults report mild/occasional_{15% adults report mild/occasional} – Increases with age_{Increases with age}

“

“Sleep-state-misperception”: Sleep-state-misperception”:

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Insomnia (Continued)



_{Causes of Insomnia:}

– Anxiety_Anxiety – Tension_Tension – Stress_Stress

– Depression_Depression

– drugs (cocaine)_{drugs (cocaine)}



_Treatments:

– _{Sedative pills}_{Sedative pills}

 _Problems:_Problems: overdose, dependency, de-sensitization, carry-_{overdose, dependency, de-sensitization,} carry-over effects

over effects

– Sleep restrictions_{Sleep restrictions}

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Sleep Disorders (Continued)

 Somnambulism (Sleep Walking) _{Somnambulism (Sleep Walking)} - -

person arises and wanders while asleep person arises and wanders while asleep

– tends to occur in first 2 hours of sleep_{tends to occur in first 2 hours of sleep} – causes unknown_{causes unknown}

– Not_Not related to emotional or psychological related to emotional or psychological problems

problems

– Occurs mostly in children, peak at 11-12 yrs_{Occurs mostly in children, peak at 11-12 yrs} – It _ItISIS safe to awaken people gently from safe to awaken people gently from

sleepwalking

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Sleep Disorders (Continued)

 Nightmares_Nightmares – anxiety-arousing dreams, – anxiety-arousing dreams, lead to awakening from REM sleep

lead to awakening from REM sleep

– correlation between stress and nightmares_{correlation between stress and nightmares} – prevalent in 10% adults_{prevalent in 10% adults}

– persistent nightmares in children may _{persistent nightmares in children may}

– reflect emotional disturbance_{reflect emotional disturbance}

 Night terrors _{Night terrors}– abrupt awakenings from Non-REM – abrupt awakenings from Non-REM sleep accompanied by intense arousal and panic sleep accompanied by intense arousal and panic

- most common in children 3-8_{most common in children 3-8}

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Dreams

What We Dream

And

Why We Dream

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Why

do we dream?

1.

1. Wish FulfillmentWish Fulfillment:: Sigmund Freud suggested Sigmund Freud suggested the dreams provide a psychic safety valve to the dreams provide a psychic safety valve to

discharge unacceptable feelings. The dream’s discharge unacceptable feelings. The dream’s

manifest (apparent) content may also have manifest (apparent) content may also have

symbolic meanings (latent content) that signify symbolic meanings (latent content) that signify

our unacceptable feelings. our unacceptable feelings.

2.

2. Information Processing:Information Processing: Dreams may help sift, Dreams may help sift, sort, and fix day’s experiences in our

sort, and fix day’s experiences in our memories.

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Why do we dream?

3.

3. Activation-Synthesis TheoryActivation-Synthesis Theory:: Suggests that in Suggests that in

the brain engages in a lot of neural activity that is the brain engages in a lot of neural activity that is

random. Dreams make sense of this activity. random. Dreams make sense of this activity.

All dream researchers believe we need REM sleep. When deprived of REM sleep, and then allowed to sleep,

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What

do we Dream?

1.

1. Negative Emotional Content:Negative Emotional Content: Eight out of 10 Eight out of 10 dreams have negative emotional content.

dreams have negative emotional content. 2.

2. Failure Dreams:Failure Dreams: People commonly dream People commonly dream about failure, being attacked, pursued,

about failure, being attacked, pursued, rejected or struck with misfortune.

rejected or struck with misfortune. 3.

3. Sexual Dreams:Sexual Dreams: Contrary to our thinking Contrary to our thinking

sexual dreams are sparse. Sexual dreams in sexual dreams are sparse. Sexual dreams in