Test 3: Sleep Flashcards
(69 cards)
1
Q
Sleep is a _____ and _____
A
behavior and altered state of consciousness
2
Q
What are the two theories of sleep?
A
- Adaptive response
- Restorative response
3
Q
What does the adaptive response theory of sleep say?
A
- Sleep is a useful bx inherited from our ancestors
- Keeps us out of harm’s way
- Many animals only obtain food during part of the day-night cycle
4
Q
What does the restorative response theory of sleep say?
A
Sleep accomplishes some sort of restoration from the effects of wear and tear that occur during wakefulness
- Brain activity is reduced during SWS (delta activity)
- Persons awakened from SWS appear groggy and confused
- Sleep seems to help the brain function normally
5
Q
What are the stages of sleep and how long is spent in each of them?
A
Stage 1 (transition between wake and sleep): 5%
Stage 2: 45%
Slow wave sleep:
- Stage 3: 12%
- Stage 4: 13%
Rapid Eye Movements (aka paradoxical sleep) 25%
6
Q
Electroencephalogram (EEG)
A
- An electrical brain potential
- Electrode placed on scalp
- Summed postsynaptic activity of cerebral neurons
7
Q
Electromyogram (EMG)
A
- An electrical potential from muscles recorded from an electrode placed on a muscle
- Electrode placed on chin
8
Q
Electro-oculogram (EOG)
A
- An electrical potential from the eyes
- Electrode placed on the skin around the eyes
- Detects eye movement
9
Q
Alpha Brain activity
A
- Regular, smooth electrical activity
- Medium frequency waves, 8-12 Hz
- Associated with state of relaxation
10
Q
Beta Brain activity
A
- Irregular electrical activity
- Low-amplitutde waves of 13-30 Hz
- Associated with arousal
11
Q
Theta Brain activity
A
- 5-8 Hz
- Associated with drowsiness (Stage 1)
12
Q
Delta Activity
A
- Regular, synchronous activity
- 1-4 Hz
- Occurs during SWS
13
Q
How do we know if an animal sleeps?
A
Must show periods of inactivity with raised arousal thresholds and must show sleep debt when deprived, leading to rebound sleep when deprivation is ended
14
Q
Can you tell how much total or REM sleep an animal gets by its order?
A
No! Each is individualistic.
- “Each of these groups show a wide and overlapping range of total and REM sleep amounts”
- Genetic inheritance
15
Q
Which one sleeps more: big animals or small animals?
A
Small animals. Especially for herbivores
16
Q
Mammals have ________ amount of REM at birth and _______ with age.
A
Maximal, decrease
17
Q
Animals that are born _______ have greater elevation in REM at birth.
A
immature
18
Q
Animals that are born immature continue to __________________.
A
have increased REM
19
Q
What is unihemispheric sleep and why do cetaceans (marine mammals) do it? Does it involve REM sleep?
A
- One side of the brain sleeps at a time.
- Allows continued breathing in water
- No evidence for REM
- If one hemisphere is prevented from sleeping, that hemisphere will have a rebound
20
Q
Prolonged sleep deprivation (2-3 weeks) in rats results in ____.
A
Death
21
Q
What are side effects of sleep deprivation in rats?
A
- Loose ability to regulate body temp
- Look sick
- Stop grooming
- Eat more
- Loose weight
- May disrupt immune system
22
Q
Surprisingly, exceptional wakefulness of newborn whales and dolphins have no ______ on their development.
A
Ill-effect
23
Q
In humans, how much of total lost slepp is recovered? Which stages are recovered first?
A
- 1/3 to 1/2 total lost sleep is recovered.
- SWS (stages 3&4) are recovered 1st, followed by REM
- Little recovery of stage 2
- Sleep quality is regained but not quantity
24
Q
Are there long term, direct consequences of sleep deprivation in adults?
A
No
25
What is the longest sleep deprivation in adults?
- 264 hours
- 17 year old boy, wanted world record
- Slept 15 hours, 10 hours next night, under 9 the next
26
Differences between REM sleeps in people resting in bed for 6 weeks and those who did not?
No difference in slow wave or REM sleep
27
Do immobile quadriplegics get different sleep than uninjured people?
Slightly less slow wave sleep
28
How does temperature affect sleep?
- Exercise while hot and humid leads to increase in SWS
- Control for temp, no change in sleep
- Rise in temp of brain; head warmed with hairdryer increased slow wave sleep
29
Mental activity utilizes ____ _____. _______ activity is most intense in that region
Frontal lobes. Delta.
30
Participants taken out for a stimulating day had more or less slow wave sleep than control?
More
31
When stimulating a participant's hand while asleep, was there more or less delta activity in the somatosensory cortex?
More
32
At what stages do dreams occur?
SWS and REM sleep
33
REM seep is accompanied by ___ levels of blood flow in the visual association cortex but ____ levels in the inferior frontal cortex.
High. Low.
34
REM eye movements resemble those made when a person _________.
Scans a visual image
35
Nightmares can occur during ___.
Stage 4 of SWS
36
Does the body regulate sleep via blood-borne chemicals?
Unlikely bc:
- Siamese twins share circulatory system, but sleep independently
- unihemispheric sleep; both sides of brain in same circulatory system
37
Acetylcholine: location and function
Pons (LDT and PPT) and basal forebrain (BF)
| Activation of ACh neurons produces Bx activation and cortical desynchrony
38
Norepinephrine: location and function
NE neurons in locus coeruleus (dorsal pons) show high activity during wakefulness, low activity during sleep (zero during REM sleep)
39
Serotonin: location and function
Stimulaiton of raphe nuclei (in reticular formation) induces arousal whereas 5-HT antagonists reduce cortical arousal
40
Histamine: location and function
Hist neurons in TMN (in hypothalamus) project to cortex.
| Antihistamines cause drowsiness
41
Orexin (Hypocretin): location and function
- neurons in the lateral hypothalamus project to other arousal areas (LC, raphe TMN, LDT/PPT, BF)
- Incrases during active wake and REM
- Decreases during quiet wake and SWS
- Orexin plays a role in motor activity
- Narcolepsy resutls from degeneration of orexin neurons
42
What is narcolepsy?
Sleep appears at odd times. Sleep attack: irresistible urge to sleep during the day. Lasts 2-5 minutes and person wakes feeling refreshed
43
What is cataplexy?
REM paralysis occurs, but the person is still conscious. Usually precipitated by strong emotional reaction.
44
Why does narcolepsy occur?
Reduced CSF levels of orexin (immune system attacks orexin neurons) or mutation of the orexin B (hypocretin 2) receptor
45
How is narcolepsy treated?
Modafinil (Provigil)-activates orexin neurons
46
A person with narcolepsy is more likely to have a birthday in ______ and less likely in _______.
March, September
47
What is an area that is important in the control of sleep?
Ventrolateral preoptic area (VLPO)
48
Lesions of the VLPO lead to ___.
Total insomnia, leading to death.
Could also be less NREM sleep and more wake. REM-about the same.
49
Electrical stimulation of the VLPO in cats induces signs of _______.
Drowsiness
50
How does the VLPO promote sleep?
- VLPO neurons contain GABA
- Projects to arousal areas (LC, raphe, TMN, LDT/PPT)
- Arousal areas project to VLPO (LC, raphe, TMN) and is inhibited by HIST, 5-HT, & NE
51
What is the "flip-flop" switch?
- VLPO is active-->inhibits wake promoting areas
- Wake promoting areas active--> inhibit VLPO
- Orexin may stabilize the switch
52
Adenosine ______ in the BF during wake and _____ decreases during sleep.
Increases. Decreases
53
Adenosine agonist _____ ACh neurons and _______ sleep
Inhibits. Increases
54
The ______ is important for the control of REM sleep
Pons
55
What is the first predictor of REM sleep?
PGO (pons, geniculate, occipital) waves
56
_____ neurons in the peribrachial pons (LDT/PPT) modulate REM sleep.
ACh.
ACh agonist increases REM sleep
LDT/PPT Lesions reduce REM sleep
57
ACh neurons project to the ______ (control of corical arousal), to the ____ (arousal and desyncrony), and to the ____ (rapid eye movements)
thalamus, basal forebrain, tectum
58
Ach neurons project via ________ cells within medulla to the spinal cord
Magnocellular
Release glycine to induce REM motor paralysis or atonia
59
What is REM sleep behavior disorder? (cause and symptoms)
- Neurodegenerative disorder often associated with Parkinson's disease and multiple system atrophy
- Can be caused by brain damage to the brain stem
- Person fails to show paralysis during REM sleep. Acts out dreams.
- Different from sleep walking (somnambulism)
60
When do sleep walking, bedwetting, and night terrors occur?
SWS, especially stage 4
61
Know REM sleep summary
Know REM sleep summary
62
When are 5-HT and NE lowest?
Low during sleep and lowest during REM sleep
63
What is insomnia? What are some causes?
Difficulty in getting to sleep or remaining asleep
Causes:
-Situational
-Drug-induced
-Sleep apnea: person stops breathing and is awakened when blood levels of carbon dioxide stimulate breathing
64
Drug treatments for short term insomnia
Antihistamines-block wake promoting histamine
Non-benzodiazpine hypotics-GABA agonists (Ambien, Sonata, Lunesta)
Melatonin Receptor Stimulator-Rozerem
Benzodiazepines (mainly paraxomnias)-GABA agonists (Restoril, Valium, Librium)
Alcohol-GABA agonist
65
Psychological and Behavioral Tx for Insomnia
- Stimulus control therapy
- Sleep restriction therapy
- Relaxation training
- Cognitive therapy
- Sleep hygiene educaiton
- CBT
66
Drug treatments for excessive daytime sleepiness
- Caffiene-blocks AD receptors
- Amphetamines-DA/NE agonist
- Non-amphetamine stimuants-Unknown mechanism of action. DA or orexin agonist?
67
Drug treatments for narcolepsy
- Amphetamines and non-amphetamines
- GHB-GABA and GHB agnonist. Can be used as date rape drug
- Antidepressants-monoamine reuptake inhibitors
68
Obstructive Sleep Apnea
Throat closes during sleep, breathing temporarily ceases, followed by microarousal and reestablishment of airway.
Treatment: medications, surgery, or CPAP
69
Sleep Hygiene
```
Listen to your body clock
Use your bed only to sleep
Get up and go to bed at the same time
Exercise in the morning and in the early afternoon
• Don’t exercise in the evening
Stop looking at that clock
Avoid alcohol, caffeine, and nicotine
Naps
• Not after 4 pm and not more than 30-45 minutes
Keep the bedroom dark, quiet, and cool
Eat a light snack
Don’t worry too much
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