L18 Sleep (Imported from Quizlet)

Change in behaviour, change in brain activity, structural changes, gene expression

What happens during sleep?

Non-REM, REM

Sleep consists of cycles of ____-_____ and ____ sleep

Rapid eye movement

What does REM stand for?

Reduced motor activity, reduced response to stimulation, stereotypic postures (eyes closed in humans), relatively easy reversibility

Sleep defined behaviourally as ...?

Electrical recordings

Physiological activity can be conveniently measured using __________ __________

Muscle

Which movements is measured using electromyography?

Eye

Which movements is measured using electro-oculography?

Brain

Which activity is measured using electroencephalography?

Synchronous, electrical, neurones, brain

Electroencephalogram measured the _________, __________ activity from large populations of ________ in the _______

Cellular, ionic movements

What creates an electric field that is then measured by electrodes placed on the surface of the scalp in electroencephalography?

An electrical amplifier (they are tiny electrical fields) and to a monitor

What are the electrodes placed on the scalp to detect electrical fields linked to?

Invasive, temporal, spatial

Electroencephalography is non-_______, easy to administer, data is easily gathered, has high _________ resolution (milliseconds) and low _______ resolution

Cortical activity

Electrical fields follow an inverse square law so only _________ __________ detectable

Many types of brain waves

What does this image show?

4

How many stages are there in non-REM sleep?

Not much action potential firing between neurones

Neuronal activity is low in non-REM sleep, what does this mean?

Lowest

Is metabolic rate and brain temperature at their lowest or highest during non-REM sleep?

Decreased sympathetic nervous system outflow

Heart rate and blood pressure decline during non-REM sleep, what does this mean?

Parasympathetic

In the stages of non-REM sleep there is an increase in _______________ nervous system

Muscle, reflexes

_________ tone and _______ are intact during non-REM sleep

Drowsiness

What is the first stage of non-REM sleep?

Awakened easily

Eyes move slowly and muscle activity slows

During this stage, many people experience sudden muscle contractions preceded by a sensation of falling

What are the properties of stage 1 of non-REM sleep?

Several minutes

Transition from wakefulness to onset of sleep lasts how long?

Low, sinusoidal

Awake people show ____ voltage EEG activity (10-30μV@16-25Hz)

As they relax - _____________ (alpha) activity 20-40μV@Hz

Eyes show slow, rolling movements

Describe what is happening in EOG

During Stage 1 and all non-REM - some muscular activity

Describe what is happening in EMG

Low-voltage, frequencies

EEG characterised by ____-_________ activity if mixed ____________ (mostly theta waves)

Light sleep

What is stage 2 of sleep?

Eye movement stops and brain waves become slower with only an occasional burst of rapid brain waves

The body begins to prepare for deep sleep

Body temperature drops, heart rate slows

Describe the properties of Stage 2 of non-REM sleep

Sinusoidal, sleep spindles, biphasic, K complexes

Stage 2 of non-REM sleep is characterised by bursts of ____________ waves called '_______ ___________' (12-14Hz) and ___________ waves called _ ________

Episodically, low

K complexes occur ___________ against background of continuing ___-voltage EEG activity

Deep sleep

What is stage 3 of non-REM sleep?

Extremely slow delta waves are interspersed with smaller, faster waves

Describe the properties of Stage 3 of non-REM sleep

Sleepwalking, night terrors, talking during one's sleep and bedwetting 'parasomnia'

What occurs during the transitions between non-REM and REM sleep?

High amplitude, slow delta waves (0.5-2Hz)

Describe the EEG of Stage 3 of non-REM sleep

Very deep sleep

What is Stage 4 of non-REM sleep?

Brain produces delta waves almost exclusively

Disorientation for several minutes following arousal from stage 4

Describe the properties of Stage 4 of non-REM sleep

Slow, increases

______ wave activity _________ and dominates the EEG record

Slow wave sleep

Stages 3 and 4 in humans called ______ ______ _________

Stages of non-REM sleep compared

Rapid eye movement (REM) sleep

What is Stage 5 of sleep?

Wakefulness

In Stage 5, what does EEG mimic?

Birds

REM is also found where?

Closed eyes move rapidly from side to side (perhaps related to the intense dream and brain activity)

What happens during Stage 5?

Stage 1/awake, low, frequency

EEG during human REM is similar to ________ _/______ -> ____ voltage mixed ____________

REM-neuronal firing very like in wakefulness

Stage 5 is paradoxical, what does this mean?

Rise, increased, greater

During REM sleep, brain temperature and metabolic rate ______, this is consistent with ___________ neural activity in some areas - _________ than in waking

Skeletal

During REM sleep, all _________ muscles are atonic

Flaccid and paralysed

What is atonic?

Muscles controlling movements of eye, middle ear ossicles and diaphragm (so you can breathe and hear any impending danger)

During REM sleep, which muscles remain active?

Cyclically

REM and non-REM sleep alternate __________

Non-REM sleep pattern

70-80, 8-10

After __-___ minutes sleep returns to stages 3 or even 2 before entering the first REM phase of the night which lasts _-__ minutes

90-110

Time from first stage to the end of REM = __-___ minutes

Decrease, increases

Repeated four or five times during the night - during each repetition, stages 3 and 4 __________ in duration and REM __________

5

In young adults, only _% of sleep time spent in Stage 1

50-60

In young adults, largest amount of sleep time is spent in Stage 2 - __-__% in Stage 2

15-20

In young adults, Stages 3 and 4 only constitute __-__%

20-25

In young adults, REM phases constitute only __-__%

Diffuse modulatory neurotransmission system

NE and 5-HT neurons in the brains stem

Diffuse modulatory system controls rhythmic behaviour in the Thalamus

Inhibition of motor neurons

Regulation of sleep

Sleep and coma

Lesions in the brain stem can cause ...?

Precedes, causes

Activation of neurons in the brain stem __________ awakening - stimulation of brain stem ________ awakening

Depolarising

What kind of effect is there in wakefulness?

Decrease

In the non-REM stage, there is a __________ of firing in the brain stem

Spindles

In non-REM stage, what result from correlated activity in the thalamus?

Activity in the thalamus

In non-REM stage, delta rhythms result from what?

Awake

REM stage has fairly similar firing in an ______ state (but not early sensory systems)

Frontal lobe, raphe nuclei, locus coeruleus

In REM stage, there is no activity in the _________ _____ and no activity in ______ _______ and _____ ___________

Motor neurons

In REM stage, there is inhibition of what?

Strange imagery - brain not fully functioning

Exercises synapses when no external activity

'Memory consolidation'

'Circuit testing'

What are the theories of dreaming?

Circadian rhythm, 24

Sleep and wakefulness follow ___________ __________ with periodicity of about ___ hours

Endogenous, environmental

Circadian rhythms are ____________ and persist without ________________ cues

External timing cues

Circadian rhythms are modulated by what?

External timing cues that adapt the rhythm to the environment

What are 'Zeitgebers'?

Sensory stimulation

Circadian clocks require _________ _____________ but works without them as well

Suprachiasmatic nucleus, anterior hypothalamus

Major internal clock is ___________________ _______ of ___________ _______________

The circadian rhythm of sleep

Lesioning of the suprachiasmatic tract dampens down what?

Timing of sleep, sleep itself

Suprachiasmatic nucleus regulates _________ ___ ______ - it is not responsible for _______ __________

Intrinsically photosensitive ganglion cells

What provides input to the suprachiasmatic nucleus?

Lesioning of the suprachiasmatic tract dampens down what?