View
236
Download
1
Category
Tags:
Preview:
Citation preview
SleepSleep
“… if you’re sleeping are you dreaming, if you’re dreaming are you dreaming of me? …”
-Blue October
“… if you’re sleeping are you dreaming, if you’re dreaming are you dreaming of me? …”
-Blue October
SleepingSleeping
Average individuals spend 1/3 of their lives asleep
Sleep is at the lowest level of the hierarchy of consciousness
Sleep allows for near immediate return to the highest level of consciousness through presentation of appropriate stimulus
Average individuals spend 1/3 of their lives asleep
Sleep is at the lowest level of the hierarchy of consciousness
Sleep allows for near immediate return to the highest level of consciousness through presentation of appropriate stimulus
Historical DevelopmentHistorical Development
Little scientific inquiry until late 1800s
1870-1890: Two scientists separately found importance of rostral midbrain legions in lethargy syndromes
Little scientific inquiry until late 1800s
1870-1890: Two scientists separately found importance of rostral midbrain legions in lethargy syndromes
Historical DevelopmentHistorical DevelopmentEncephalitus Lethargica: Commonly
called sleeping sickness, is a degenerative viral inflammation in the brainWorldwide epidemic from 1916-1926Search for pathological basis led to
conclusions of two sleeping centers in the brain:A Waking Center: Turns off sleep when stimulated
(posterior hypothalamus and mesencephalic tegmentum)
A Sleep Center: Turns on sleep when activated (in the basal forebrain structures)
Encephalitus Lethargica: Commonly called sleeping sickness, is a degenerative viral inflammation in the brainWorldwide epidemic from 1916-1926Search for pathological basis led to
conclusions of two sleeping centers in the brain:A Waking Center: Turns off sleep when stimulated
(posterior hypothalamus and mesencephalic tegmentum)
A Sleep Center: Turns on sleep when activated (in the basal forebrain structures)
Historical DevelopmentHistorical Development
1930’s brought about clinical use of EEGs and different sleep brain wave patterns were labeled
1950’s: Generally accepted that regions for both sleeping and waking existed in the pons and medulla, and that sensory input to the brain was not a necessary condition for organisms to demonstrate signs of wakefulness
1930’s brought about clinical use of EEGs and different sleep brain wave patterns were labeled
1950’s: Generally accepted that regions for both sleeping and waking existed in the pons and medulla, and that sensory input to the brain was not a necessary condition for organisms to demonstrate signs of wakefulness
Brain WavesBrain Waves
Differ in Amplitude (height of wave) and Frequency (rate of occurrence)
Desynchronization: patterns of electrical activity in a typical EEG reading. aIrregular low amplitude activity with no particular pattern
Synchronization: EEG produces distinct regular patterns of brain waves of approximately the same amplitude with a regular frequency
Differ in Amplitude (height of wave) and Frequency (rate of occurrence)
Desynchronization: patterns of electrical activity in a typical EEG reading. aIrregular low amplitude activity with no particular pattern
Synchronization: EEG produces distinct regular patterns of brain waves of approximately the same amplitude with a regular frequency
Brain WavesBrain Waves
Beta (14-30 Hz): Parietal and Frontal cortical regions, characteristic of wakefulness
Alpha (8-13 Hz): Individuals who are awake but in a quiet resting state with eyes shut
Theta (4-7 Hz): Commonly seen in children under 10 as well as adults under conditions as simulated diving, chemical intoxication, sleep and meditation
Delta (.5-4 Hz): Deep sleeping adults as well as children
Beta (14-30 Hz): Parietal and Frontal cortical regions, characteristic of wakefulness
Alpha (8-13 Hz): Individuals who are awake but in a quiet resting state with eyes shut
Theta (4-7 Hz): Commonly seen in children under 10 as well as adults under conditions as simulated diving, chemical intoxication, sleep and meditation
Delta (.5-4 Hz): Deep sleeping adults as well as children
How to Study Sleep:How to Study Sleep:
First night effect: the first night spent in a sleep laboratory usually produces abnormal brain waves - unreliable data!
First night effect: the first night spent in a sleep laboratory usually produces abnormal brain waves - unreliable data!
Sleep StagesSleep Stages
Stage 1:Body begins to show signs of relaxation,
muscle tonus diminishes, heart rate slows, and breathing becomes deeper and more regular
Brain wave activity is desynchronous, 12-17 Hz is most prominent frequency
Not difficult to arouse a person in stage 1 sleep
Only happens as you are first falling asleep
Stage 1:Body begins to show signs of relaxation,
muscle tonus diminishes, heart rate slows, and breathing becomes deeper and more regular
Brain wave activity is desynchronous, 12-17 Hz is most prominent frequency
Not difficult to arouse a person in stage 1 sleep
Only happens as you are first falling asleep
Sleep StagesSleep Stages
Stage 2:Sleep Spindles: Sinusoidal wave with
frequency 12-14 Hz. Associated with loss of perceptual awareness and occur in transition between stage 1 and stage 2
K-Complex: Biphasic wave form beginning with an initial, sharp negative wave followed by positive components
Stage 2:Sleep Spindles: Sinusoidal wave with
frequency 12-14 Hz. Associated with loss of perceptual awareness and occur in transition between stage 1 and stage 2
K-Complex: Biphasic wave form beginning with an initial, sharp negative wave followed by positive components
Sleep StagesSleep Stages
Stage 3:Muscle Tonus, heart rate, blood pressure ad
body temperature all show signs of decreasing
Takes relatively large stimulus to awaken someone
Onset and termination defined by percentage of delta wave activity
Consists of the times when 20-50% of EEGs are delta wave
Stage 3:Muscle Tonus, heart rate, blood pressure ad
body temperature all show signs of decreasing
Takes relatively large stimulus to awaken someone
Onset and termination defined by percentage of delta wave activity
Consists of the times when 20-50% of EEGs are delta wave
Sleep StagesSleep Stages
Stage 4Begins when over 50% of EEG activity
is delta wavesVery deep stage of sleep and
extremely difficult to awakenIf allowed to sleep interrupted, will go
from stage 4 to stage 3 to stage 2Night terrors occur during this stage
of sleep
Stage 4Begins when over 50% of EEG activity
is delta wavesVery deep stage of sleep and
extremely difficult to awakenIf allowed to sleep interrupted, will go
from stage 4 to stage 3 to stage 2Night terrors occur during this stage
of sleep
Sleep StagesSleep Stages
REM SleepOccurs ever 30-90 minutes
throughotu the night, sleeping subjets go from stage 2 to REM
Low voltage, mixed frequncies, punctated by occastional bursts of alpha activity
Eyes dart back and forth behind closed eyelids about 50-60 times per minute (gives REM its name)
REM SleepOccurs ever 30-90 minutes
throughotu the night, sleeping subjets go from stage 2 to REM
Low voltage, mixed frequncies, punctated by occastional bursts of alpha activity
Eyes dart back and forth behind closed eyelids about 50-60 times per minute (gives REM its name)
Sleep StagesSleep Stages
REM SleepRespiration and pulse rates increase and
become irregular, blood pressure increasesMale subjects often experience erectionsThis is when dreaming occurs (though it can
sometimes occur in NREM sleep, just unlikely they will be remembered)
Greater right hemispheric involvement in REM sleep while greater left hemispheric activation in NREM sleep
REM SleepRespiration and pulse rates increase and
become irregular, blood pressure increasesMale subjects often experience erectionsThis is when dreaming occurs (though it can
sometimes occur in NREM sleep, just unlikely they will be remembered)
Greater right hemispheric involvement in REM sleep while greater left hemispheric activation in NREM sleep
Age Related ChangesAge Related Changes
Age related changes contribute to the excessive daytime sleepiness observed in the elderly
Total time spent in stage 4 and REM decreases with age
Lack of flexibility in sleep patterns as people age
Age related changes contribute to the excessive daytime sleepiness observed in the elderly
Total time spent in stage 4 and REM decreases with age
Lack of flexibility in sleep patterns as people age
HypnopediaHypnopedia
Hypnopedia: The possibility of learning during sleepNo study has been able to show
convincingly an ability to learn complex verbal material during sleep
Learning such material when awake appears to be facilitated slightly as compared with the rate that similar (but new) material is learned
Hypnopedia: The possibility of learning during sleepNo study has been able to show
convincingly an ability to learn complex verbal material during sleep
Learning such material when awake appears to be facilitated slightly as compared with the rate that similar (but new) material is learned
Other things in the book:Other things in the book:
Sleep deprivation Sleeping Disorders Theories of Sleep: Answers to why do we
sleep? When do we dream and what is it about? Theories on Dreaming (Freud etc) Day dreaming Sexual fantasies
Sleep deprivation Sleeping Disorders Theories of Sleep: Answers to why do we
sleep? When do we dream and what is it about? Theories on Dreaming (Freud etc) Day dreaming Sexual fantasies
Recommended