States of Consciousness:Waking and Sleeping Rhythms

Intro PsychModule 15

Apr 28, 2010Class #39

Working definition…

• Consciousness– Is an awareness of the environment

and of one’s own mental processes

Sleep and Dreams

• Lets look at this particular altered state of consciousness…

Biological Rhythms

• Circadian Rhythms– Our bodies are synchronized with the 24-

hour cycle of day and night through this biological clock

• Can be disrupted by things such as:– Jet lag – Radically altering your sleeping schedule

from weekdays to weekends• As college students often do

– Just as it begins to reset itself to the weekend sleep schedule, a new school week begins and may result in “Sunday night insomnia” and “Monday morning blues”

Sleep Cycles

• Stages of sleep are distinguished by attaching electrodes to a person’s scalp and recording brain waves from an EEG (electroencephalograph) – EEG measures patterns of activity in

the brain

Sleep Cycles

• “Pre-sleep”– When you just get into bed and close

your eyes the EEG picks up slow alpha waves of your awake but relaxed state

Stage 1• Very light sleep • Breathing rate slows• Brain waves display theta waves (these are

slower and more irregular)• Only lasts about two to five minutes• You may experience fantastic images which

are similar to hallucinations– For example, you may have a sensation of falling at

which moment your body may suddenly jerk, or of floating weightlessly, or you may have a vivid visual image

• Myoclonic Jerk – short convulsion of the body which may be brought on when your brain noticing your heart rate and breathing rate decreasing more rapidly than normal sends out a burst of electrical activity to your muscles

Stage 2

• For the next 20 minutes we relax more deeply…– Although, we can still be awakened

without too much difficulty during this stage, you are now clearly asleep

– Brain activity is characterized by sleep spindles•These are periodic bursts of rapid,

rhythmic brain activity

Stage 3• Very short phase – just a few minutes • Gets us ready for deep sleep • Large delta waves are emitted

Stage 4• Deep sleep for about 30 minutes• Tough to be awakened during this stage• Curiously, it is during this stage in which

people talk or walk and young children wet their beds

• Other curious things – we may be undisturbed by the roar of a loud vehicle but if we hear the cry from a baby in the next room we can be awakened

Back down the ladder…

• About an hour after we fall asleep another strange phenomenon occurs…

• Rather than continuing in deep slumber, we go back down the sleep ladder– We return to stage 3, then to stage 2

and then we enter the most intriguing sleep phase of all…Rapid Eye Movement sleep

REM sleep…• For about 10:00, brain activity

resembles Stage 1 but unlike Stage 1:• HR increases• Breathing becomes more rapid and

irregular• People rarely snore during REM sleep• Genitals show signs of arousal

– Erection in males– Vaginal lubrication is possible in women

• Every 30 seconds or so your eyes dart around in a momentary burst of activity under your closed lids

EEGs During the Stages of Sleep EEGs During the Stages of Sleep

Webb, Wilse B., Sleep: An Experimental Approach, 1968, p.15. Reprinted by permission of Prentice-Hall, Upper Saddle River, New Jersey.

Its called the “paradoxical sleep”…

• REM is often referred to as paradoxical because the increased eye movements, HR, respiration, and genital activity suggest arousal – yet the muscles are deeply relaxed and the sleeper is not easily awakened

Its our dream stage as well…• Some of brain activity during sleep is

experienced as dreams– Mostly occurs during REM sleep– Despite senselessness, dreams often

contains some logic

• Very emotional and storylike• Not like the fleeting images of stage 1• Daytime activities seem to have minor

influence on dream content

Why the Rapid Eye Movements?

• Researchers aren’t sure

As the night wears on…• The sleep cycle repeats itself

about every 90:00 with deep stage 4 sleep becoming briefer and then eventually disappearing and REM sleep getting progressively longer

More REM sleep as the night wears on…More REM sleep as the night wears on…

Adapted from A Primer of Sleep and Dreaming by Rosalind Cartwright. © 1978 by Addison-Wesley. Reprinted by permission of the author.

REM functions…

• Extended sleeplessness leads to fatigue, irritability, and inattention…

• Some believe non-REM sleep helps restore body and brain for the next day’s activities.

• Functions of REM sleep?– May improve functioning of neurons that

use norepinephrine– May be a time for developing, checking, and

expanding the brain’s nerve connections

Sleep Deprivation

• Problems:– Chronically fatigued– Diminished immunity to disease– Slight hand tremor– Irritability– Occasional moments of inattention or

misperceptions on monotonous tasks • Example: Cross-country driving

– Note: on highly motivated tasks, sleep deprivation has little effect

Effects were more severe for this guy…

• In 1959, a New York disc jockey, Peter Tripp, attempted a publicity stunt by staying awake for 201 hours

• After three days, he began to hallucinate and turned paranoid

• It was almost as though his sleep-deprivation was allowing dream images to break into his waking consciousness

Randy Gardner (1965)• 17 tear-old who

made it into Guinness Book of World Records by staying awake for 11 days

• During the final night, he beat one of the researchers 100 straight times in a pinball game

Gardner today…”no more all-nighters”

This guy finally broke the record in 2007

Tony Wright, a 42-year-old horticulturalist

Do we need sleep?• The answer is yes!

– Although, our bodies can be trained to do with gradually less sleep

– Although, Gardner felt nauseous at times, had difficulty reading, and suffered temporary memory lapses, he had no long-term emotional or physical side-effects but eventually we need it to cope with stressors, etc.

• Measurements have been taken, however, that indicate there are some chemical changes during sleep deprivation – so yes, our body does need sleep!

Sleep (REM) rebound???

• Dement (1999)– We keep track of a sort sleep debt and

then eventually rebound– Our brain keeps an accurate account of

sleep for at least two weeks

• REM Rebound– Part of this rebound involves REM sleep– If deprived of this, we immediately go

right back to this stage

Maybe we shouldn’t sleep so much…

• Kripke (2002)– This six-year study

of more than one million adults ages 30 to 102 has shown that people who get only 6 to 7 hours a night have a lower death rate than individuals who sleep 8 hours or more

Graphs indicate that under 4.5 is not good either…

Lucid Dreaming Lucid Dreaming

• Awareness that a dream is a dream while it is happening

• Laberge (1985) – Feels that although we are not usually

explicitly aware of the fact that we are dreaming while we are dreaming, at times a remarkable exception occurs, and we become conscious enough to realize that we are dreaming

Lucid Dreaming

• Snyder & Gackenbach (1988)– Lucid dreaming is normally a rare experience– Though most people report having had a

lucid dream at least once in their lives, only about 20% of the population reports having lucid dreams once a month or more

LaBerge (1980; 1985)– Reported that if subjects deliberately

attempted to feel the bedcovers they know they are sleeping in or try to hear the ticking of the clock they know is beside their bed, they fail to feel or hear anything except what they find in their dream worlds

Can we control our dreams???• Apparently, with practice we can

achieve lucidity and have some degree of control over the course of the dream– For example, one woman mentioned

that when she can decide in her dream to face up to a frightening figure or try to avoid the danger

Abnormalities of Sleep

• Insomnia• Narcolepsy• Sleep Apnea• Night Terrors• Hypersomnia• Sleepwalking

Insomnia• Most common sleep disorder

– 15% of adults complain of this• Difficulty falling asleep• Waking up frequently• Waking up too early• Unrefreshing sleep• One feels daytime fatigue due to trouble

falling asleep or staying asleep– Note: Not defined by the number of hours of

sleep a person gets

Causes of Insomnia• Advanced age

– Occurs more frequently after the age of 60

• Gender– Females

• A history of depression– Main reason

How its treated…

• Over-the counter sleep medications– Not recommended

• Prescription sleeping pills– Controversial

• Behavioral techniques– Relaxation therapy

• Warm milk– Worth a try? – can’t hurt

Narcolepsy• Sudden attacks of extreme sleepiness usually

in the middle of the day• The person collapses directly into a brief

period of REM sleep – with its accompanying loss of muscular tension

• Cataplexis– The loss of muscle tone without loss of

consciousness– Are frequently prompted by laughter,

embarrassment, anger and even sexual intercourse may trigger an episode

• Sleep Paralysis• Estimated 100,000 or more in U.S. suffer from

this

Risks and Causes

• Risks– Motor vehicle accidents– Dangerous machinery, etc.

• Cause– Unknown but in seems to run in

families•Dement (1972)

–Narcoleptic Dogs

Sleep Apnea

• Cessation of breathing for a short period of time while sleeping

• An airless minute or so• The decreased oxygen in the blood

arouses the sleeper to snort in air for a few seconds

• The process is repeated hundreds of times during a night’s sleep

Sleep Apnea

• Often not aware of there problem • Can lead to insomnia• At highest risk are obese or

middle-aged men• They just can’t seem to find a

sleeping position that allows them to breath easily

Sleep Apnea

• Continuous Positive Airway Pressure– Most common treatment is a mask

worn over the nose while sleeping

Night Terrors

• Mysterious sleep disturbances that preschoolers and older children are occasionally subject to

• They are usually subjected to these horrific dream images one to four hours after falling asleep – during stage 3 or stage 4 sleep– Can last from 10-40 minutes– Child may bolt out of bed, run wildly about

house with eyes open, screaming, etc.– He is not awake and usually not aware of your

presence– No recollection in the morning

• About 5% of children will have at least one episode

Night Terrors• Don’t try to intervene unless

he/she is in danger• Let them scream in out

• Note: Nightmares occur during REM sleep and are often remembered

Hypersomnia• Excessive sleepiness

– They sleep a lot but its unrefreshing no matter how long

• Typical case– 8-9 hours during the week and then 18-22

per day on the weekends to “catch up on lost sleep”

• Risk Factors– Obesity– Female– Depression

• Causes – Unknown but some have linked it to head

traumas, viral infections, or mood disorders

Sleepwalking

• Usually affects children between the ages of 6-12 before they enter puberty although it can occur in adults as well

• Children will usually go to bed in a normal manner but arise during their second or third hour of sleep

• Occurs in non-REM sleep• They remember nothing• Their eyes are partially or fully open and they

void things, listen when spoken to, respond to commands (Johnny -- return to your bed!)

• Episodes last about 15-30 minutes• Don’t shake them but gently guiding them is

okay