Psych 211 Sleep And Arousal

Front 1

sleep is...

Back 1

a behaviour which we spend 1/3 of our lives doing

Front 2

EEG, EMG, EOG

Back 2

EEG: Electrodes are attached to the subjects scalp to record electrical activity of the brain.
EMG: Electrodes are also attached to the subjects chin to record muscle activity
EOG: Electrodes placed around the eyes monitor eye movements

Front 3

stages of non rem sleep

Back 3

Stage 1:transition between awake and sleep: theta waves
Stage 2: after ten min, irregular EEG, theta, sleep spindles, k complexes
Stages 3 and 4: high amplitude delta waves (occur more often in stage 4) Where there is a descending phase there is a period of inhibition in cortical neurons

Front 4

sleep spindles; k complexes

Back 4

- Sleep spindles are short bursts of waves (12-14 Hz) which occur between 2-5 times a minute during sleep stages 1-4.

- Older people show more K complexes. K complexes are sudden, sharp waveforms. They are found during stage 2 only. They occur spontaneously at approximately 1 per minute and can be triggered by unexpected noise!

Front 5

REM sleep

Back 5

- 90 min after sleep, lasts 20-30 min
- activity desynchronized, theta and beta activity
- muscles paralyzed
- metabolic rate increased
- if you wake someone up in REM they are alert and can tell you their dream
- aka paradoxal sleep

Front 6

slow wave sleep

Back 6

Stages 3-4 are referred to as slow-wave sleep because of slow, high amplitude delta waves.

- At stage 4 you’re usually in deep sleep. Can’t be awakened by noise. Cerebral blood flow and oxygen consumption decrease.

Front 7

Describe mental activity during sleep

Back 7

- people who report their dreams are 'conscious' during sleep
- there is high blood flow to the visual association cortex
- There is low blood flow to the primary visual cortex (because the retina is not receiving any light) and the prefrontal cortex (which makes dreams temporally disorganised).

Front 8

What is a reason why we sleep?

Back 8

The brain must restore itself from the effects of oxidative stress. ----> free radicals are trying to find another electron and this causes stress. exercise/activity causes free radicals!

Front 9

Yolked- control procedure

Back 9

both animals receive the same amount of treatment at the ‘same’ time. Both rats received equal amounts of exercise but only one animal was sleep deprived (the experimental rat).

Front 10

REM sleep functions

Back 10

- facilitates learning
- growth (70% of baby sleep is REM)
- consolidates memories

Front 11

Insomnia; causes (5)

Back 11

- characterized by persistent difficulty falling asleep or staying asleep
- causes: - Psychoactive drugs or stimulants (e.g. caffeine, amphetamine, cocaine, herbs).
- Hormonal shifts (e.g. preceding menstruation and during menopause).
- Psychological problems (e.g. fear, stress, anxiety)
- Changes in circadian rhythms (e.g. Shift work, jet lag
- Abuse of sleeping medications produce drug dependent insomnia

Front 12

Sleep Apnea

Back 12

Sleep apnea is insomnia caused by the inability to sleep and breath at the same time.
-the level of carbon dioxide in the blood stimulates chemoreceptors which wake the person up gasping

Front 13

Narcolepsy symptoms (3)

Back 13

- ‘Sleep attack’ is an overwhelming urge to sleep. (usually in boring monotonous situation)
- 'Sleep paralysis' is caused by REM sleep that intrudes during waking hours. The person is unable to move just before the onset of sleep and upon waking in the morning. May show hypnagogic hallucinations.
- 'Cataplexy 'is when a person suddenly wilts and falls down. It is precipitated by strong emotional reactions or sudden physical effort (e.g. laughter, anger, excitability).

Front 14

Narcolepsy causes facts

Back 14

- genetic
- caused by destruction of orexin neurons
- caused by a mutation of a gene that produces a receptor for the peptide neurotransmitter Orexin B
- Patients with narcolepsy are born with hypocretinergic/ Orexinergic neurons but the immune system attacks these neurons usually during adolescence.

Front 15

REM sleep Behaviour disorder; treated with what

Back 15

do not exibit paralysis during REM so act out dreams, eat a lot, have hallucinations
- treated with clonazepam (a benzodiazepine tranquillizer)

Front 16

Problems with slow wave sleep

Back 16

Bedwetting, sleepwalking (NOT acting out dream), night terrors

Front 17

Which 5 neurotrans play a role in arousal?

Back 17

ACh, Norepinephrine, serotonin, histamine, Orexin (hypocretin)

Front 18

Where are ACh neurons located? if we electrically stimulate___ it stimulates release of ACh in cerebral cortex

Back 18

Dorsal pons, basil forebrain, medial septum;
dorsal pons region

Front 19

ACh release in ___,___ and ___ is associated with animals level of arousal

Back 19

striatum, hippocampus and frontal cortex

Front 20

NE (norepinephrine ) neurons are located where?

Back 20

Locus Coeruleus (LC), show an increase i firing when alert and decline when asleep
- LC neurons related to Vigilance- continuous attention!

Front 21

5-HT neurons are found where? stimulation of this area causes...

Back 21

raphe nuclei- reticular formation of medulla pons and midbrain;
locomotion and cortical arousal

Front 22

What happens to 5-HT neuron activity when responding to new stimuli?

Back 22

it decreases temporarily (orienting response)

Front 23

Histaminergic neurons are located___ and project to___. Histamine levels are ___ during waking and ___ during sleep

Back 23

-in the tuberomammillary nucleus (TMN) of the hypothalamus; basil forebrain which influences ACh release
- high; low- if you have low histamine levels you will sleep!

Front 24

Hypocretin/ Orexin neurons are located ____ and terminate in ____. High levels are produced when? it also plays a role in____

Back 24

-lateral hypothalamus; areas involved in arousal
- wakefulness and REM
- motor activity

Front 25

Preoptic area

Back 25

(hypothalamus)
- involved in sleep - destruction of this area causes insomia in rats adn electrical stimulation cases drowsiness/sleep

Front 26

Ventrolateral Preoptic Area (3)

Back 26

-in preoptic area, lesions of it suppress sleep.
-Neuron acticity here increases during sleep (especially if they havent slept for a while before)
- contains GABA secreting neurons which send axons to TMN, Raphe, and LC

Front 27

Describe the flip flop

Back 27

- The VLPA receives inhibitory inputs from the same regions it inhibits.
- Reciprocal inhibition characterises a flip-flop circuit which assumes an ON or OFF state.
- In the ON state, the arousal system (wake-promoting region) is active and the sleep-promoting region in the VLPA is inhibited (animal is awake). ! In the OFF state, the sleep-promoting region in the VLPA is active and wake-promoting regions of the arousal system is inhibited (animal is asleep).
- Neurons in both regions cannot be active at the same time.

- Hypocretinergic neurons stabilise the flip-flop by promoting wakefulness and inhibiting sleep otherwise we would fall asleep during waking hours (i.e. keeps flip-flop in the ON state).

Front 28

PGO waves

Back 28

REM is preceded by PGO waves (pons, geniculate, and occipital) - short eectrial bursts only measured in animals
- originate in pons and go to LGN and occipital cortex

Front 29

ACh role in REM sleep; ACh neurons responsible for REM are found in____ (2)

Back 29

- ACh agonists facilitate REM and are high during REM and Waking
- pedunculopontine nucleus (PPT) and the laterodorsal segmental nucleus (LDT).

Front 30

Peribrachial area

Back 30

contains pedunculopontine nucleus (PPT) and the laterodorsal segmental nucleus (LDT); lesions of it reduce REM sleep

Front 31

Desynchronous activity

Back 31

seen in REM- many dif neurons firing - brain very excited

Front 32

Sublaterodorsal Nucleus (SLD)

Back 32

contains REM-ON neurons - stimulating it elicits REM sleep j

Front 33

Ventrolateral Periaqueductal Gray matter (vlPAG)

Back 33

contains REM-OFF neurons; stimulating it supresses REM

Front 34

Zeigebers

Back 34

any outside thing that synchronizes bodies internal time keeping system- LIGHT

Front 35

circadian rhythm; controlled by what

Back 35

- The daily change in behaviour that follows a cycle of approximately 24 hours
- controlled by SCN

Front 36

If you keep rats in complete darkness, a breif period of light will...

Back 36

reset internal clock

Front 37

Suprachiasmatic Nucleus (SCN); receives projections from

Back 37

internal biological clock in rats located here
lesions of it disrupts circadian rhythms and sleep cycle but does not disrupt total amount of sleep
; retina

Front 38

Alpha activity; Beta Activity: Theta Activity: Delta Activity

Back 38

1)smooth, 8-12 Hz- relaxation
2) irregular 13-30 Hz- arousal
3) slow wave 3.5-7.5 Hz
4) regular, synchronical, less than 4 Hz during deepest slow wave (mostly stage 4= over 50% delta)

Front 39

Up state

Back 39

period of excitation during a slow oscillation during slow wave sleep- neurons in neocortex briefly fire at high rate

Front 40

Hypnagogic Hallucination

Back 40

symptom of narcolepsy- vivid dreams that occur just before person falls asleep accompanied by paralysis

Front 41

orexin 's 2 receptors

Back 41

A and B (b is responsible narcolepsy if mutation occurs)

Front 42

Sleep- related eating disorder; treated/ provoked with what?

Back 42

person leaves bed and eats, usually without memory of it- usually treated with dopaminergenic agonists, and can be provoked by benzodiazepine

Front 43

What animals show REM sleep?

Back 43

only warm-blooded vertebrates

Front 44

Rebound Phenomenon

Back 44

increase in REM sleep after a period of REM sleep deprevation

Front 45

REm sleep is associated with _____ Slow wave with____

Back 45

REM sleep is associated with consolidation of NONDECLARATIVE / IMPLICIT memories and slow wave sleep associated with EXPLICIT/ ECLARITIVE memories

Front 46

Adenosine

Back 46

neuromodulator that is released by neurons engaging in high levels of metabolic activity - may play role in initiation of sleep as it builds up during wakefullness and is destroyed during sleep

Front 47

Locus Coeruleus is located where?

Back 47

pons near rostral end of forth ventricle (vigilance and arousal)

Front 48

Where is tuberomammillary nucleus located?

Back 48

ventral posterioe hypothalamus, rostral to mammilary bodies

Front 49

Sleep is controlled by which three types of factors/ cycles?

Back 49

homeostatic (get tired, sleep longer if sleep deprived), allostatic (interrupts homostaitvc in a dangerous situation) and circadian (time of day) factors

Front 50

What role do orexinergenic neurons play in flip flop?

Back 50

Stabilize it

Front 51

Hunger-related signals....

Back 51

activate orexin neurons

Front 52

Malanopsin; transmit info to...

Back 52

photopigment present in ganglion cells in retina whose axons transmit info to SCN, thalamus, and olivary pretectal nuclei. Without is we wouldnt have regular sleep patterns

Front 53

Advanced sleep Phase

Back 53

a 4-hour advance in rhythms of sleep and temp cycles, caused by mutation of gene (per 2) involved in rhythms of neurons n SCN

Front 54

Delayed Sleep Phase Syndrome

Back 54

a 4-hour delay in rhythms of sleep and temp cycles, caused by mutation of gene (per 3) involved in rhythms of neurons n SCN

Front 55

Melatonin

Back 55

* hormone secreted during night by pineal body plays role in circadian and seasonal rhythms
* melatonin acting on SCN receptors can affect sensitivity of the SCN neurons to zeitgebers and can itself alter circadian rythms
- reduces jet lag and shift work sleep issues

Front 56

During REM sleep, why do muscles become paralyzed and there is an decrease in muscle tone (2)

Back 56

Increased activity in GABAergic neurons in the pontine reticular formation and increased activity of descending
inhibitory neurons that synapse on alpha motor neurons in the spinal cord.