Sleep And Dreams Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is the circadian Rhythm?

A

Changes in humans hormone levels, body temperature and heart, respiration and metabolic rate over a 24hr cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does the circadian sleep-waking rhythm determine? and what is it regulated by in humans?

A

The circadian sleep-waking rhythm determines our alertness and activity levels during the day and night. In humans it is regulated by:

  1. The endogenous (internal) pacemakers of the
    - suprachiasmatic nucleus (SCN)
    - Pineal gland
  2. External resetters (zeitgeber)
    - light, which is detected at the retina and can influence
    - sound
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The SCN

A
  • The suprachiasmatic nucleus (SCN) is in the hypothalamus of the brain
  • it lies at the point where the 2 optic nerves extending from each eye meet (in a shallow impression called the optic chiasm).
  • therefore the SCN is highly influenced by the imput of light
  • the SCN sends messages to the pineal gland to regulate its melatonin production
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The pineal gland

A
  • the pineal gland is situated in the centre of the brain and is approximately the size of a pea.
  • when darkness falls, the SCN informs the pineal gland
  • the pineal gland secretes the hormone melatonin which is the body’s natural sleeping drug
  • relating to the zeitgeber of light, this is because light regulates the production of melatonin which is produced between 9pm and 7.30am which causes us to feel drowsy and sleepy.
  • melatonin in turn affects the production of seratonin
  • seratonin then concentrates in the raphe nuclei (sited near the pons).
  • the raphe nuclei secretes a substance that affects the reticular activating system (RAS) to induce light sleep
  • evidence comes from a study by jouvet (1976) who found that lesions on the raphe nuclei causes severe insomnia in cats
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What controls melatonin production and where is melatonin produced?

A

-the SCN controls melatonin production but melatonin is produced from the pineal gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is melatonin and why is it special?

A

Melatonin is a hormone and is special because it’s secretion is dictated by light and is secreted into the bloodstream when it starts to get dark

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the two primary functions of melatonin?

A
  • to help control your circadian rhythm

- regulate certain reproductive hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What affect does melatonin production have on a person?

A

Melatonin makes a person feel drowsy, and eventually fall asleep.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What stops the release of melatonin?

A

Light exposures stops the release of melatonin, and in turn, this helps control your circadian rhythm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

When do melatonin levels peak?

A
  • Melatonin levels peak in the middle of the night and then decrease towards daytime
  • melatonin secretion is low during the daylight hours and high during dark periods
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is another chemical that affects sleep?

A

Adenosine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How does adenosine work?

A
  • adenosine is created over the course of the day, as a natural byproduct of using up our internal energy stores.
  • Adenosine builds up in our neurons during the day, which causes us to gradually feel more tired as the day goes on.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What happens when we sleep- Adenosine

A

When we sleep, this buildup is cleared and the levels of adenosine in the body rapidly declines and the adenosine in cells gets replaced by energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Key research study- Czeisler et al 1990

A

Exposure to bright light and darkness during night work

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Czeisler et al 1990- Aim

A
  1. To discover whether exposure to exceptionally bright light - a zeitgeber- in the night shift workplace and then total darkness for daytime sleep reset the circadian rhythm
  2. To help find a way to help night shift workers cope better with changing shift patterns
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Czeisler et al 1990- Method

A

Lab experiment which attempted to increase ecological validity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Czeisler et al 1990- Participants

A

8 men, 22-29 yrs old, all healthy. None had done previous night work, none took alcohol or caffeine during study.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Czeisler et al 1990- procedure

A

A 2 week study:
Week 1- no night shift but participants had body temperatures and salivary content of melatonin measured at different times of day and night
Week 2- participants reported to the lab with their usual work load at 9pm and finished work at 5am

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Czeisler et al 1990- IV1

A

Participants worked in rooms lit by bright lights ( at the intensity of natural sunlight) and given clear sleep instruction- to remain in the dark from 9am to 5pm in bedrooms in which light was excluded (they were given blackout blinds for their bedrooms)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Czeisler et al 1990- IV2

A

Participants worked the night shift in rooms lit by ordinary lights and given no instructions for sleep after work (during the day) all participants had meals provided for them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Czeisler et al 1990- DV

A

Measurements to track participants circadian rhythm:

  • temperature
  • saliva, to measure content of cortisol and melatonin concentration
  • Urinary excretion rate
  • score in alertness test
  • score in mental maths test
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Czeisler et al 1990- Results

A
  1. The experiment group slept 2 hours more each day than the control group
  2. After 6 days, the experimental condition found their circadian rhythm ha completely flipped to suit night shift. But those of the control group showed little or no change. This was shown because melatonin, cortisol concentration and urinary excretion rate synchronised with the night work schedule so that these were similar to their previous daily circadian rhythm in the experimental group but remained the same as the week 1 measurements of the control groups.
  3. Scores in the alertness and mental maths tests in the experimental group were higher that the control group from midnight to 8am
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Czeisler et al 1990- conclusions

A
  1. Human circadian rhythm can be adapted to shift work if treated with very bright light at night and darkness during the day.
  2. This research provides evidence that use of very bright lights can reset body rhythms within 3 days- body temperature and hormone production is reset as very bright light mimics the effect of daylight. Bright lights entrain all rhythms not just the sleep-wake cycle
  3. Night shift workers should have very bright light to work in
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the two main types of sleep?

A
  • non REM sleep

- REM sleep

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Stages of Non-REM sleep

A

There are 4 stages of slow wave non-REM sleep
Stage 1 approx duration (10mins)
-heart rate slows, muscles relax and you can still be worken easily
-hallucinations occasionally occur
Stage 2 approx duration (15mins)
-deeper sleep but still can be woken easily
-EEG patterns have larger and slower waves with bursts of fast spiking activity (called sleep spindles)
Stage 3 approx duration (20mins)
-deep sleep unresponsive to external stimuli, heart rate, blood pressure and body temperature drop
-EEG shows large slow delta waves
Stage 4 approx duration (45mins)
-very difficult to wake
-EEG shows only large slow delta waves
-sleepwalking can occur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

EEG

A

EEG (electroencephalograph) was introduced in the 1930s to allow psychologists to understand more about sleep

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Stages of REM sleep

A

There is just one stage of REM approx duration (25mins)

  • EEG activity shifts into a fast desynchronised pattern similar to being awake
  • the individual is hard to wake
  • muscles relax completely, leaving the person paralysed
  • heart rate and respiration increase
  • rapid eye movements of the eye occur
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How many times are the stages of sleep cycled around per night and how long does a sleep cycle last?

A

The stages of sleep are cycled through around 5 times per night. Each sleep cycle lasts approximately 90mins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Dement and Kleitman 1957- Aim and 3 aims

A

To provide an objective study of rapid eye movement in relation to the experience of dreaming

  1. Does dreaming take place during R.E.M?
  2. Are participants aware of length of dreams 5 or 15mins?
  3. Does eye movement direction relate to dream content
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Dement and Kleitman 1957- Participants

A

7 adult males and 2 females which were all volunteers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Dement and Kleitman 1957- research method

A

Laboratory experiment using observation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Dement and Kleitman 1957- procedure

A
  • subjects slept individually in a quiet dark laboratory room after a normal day’s activity
  • alcohol and caffeine were avoided during the days
  • electrodes were connected on scalp to measure brain waves and near the eyes to register rapid eye movement
  • subjects were awoken at various time during the night by a loud doorbell noise, and immediately reported into a recording device: whether they had been dreaming
  • dreaming was only counted if a fairly detailed and coherent dream was reported
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Dement and Kleitman 1957- study 1

A

Subjects were woken by a bell REM and non-REM eye movement was recorded and Ps reports were compared to see if they had been dreaming

34
Q

Dement and Kleitman 1957- study 2

A

Subjects were awoken either 5 or 15 minutes after REM sleep began and were asked to estimate the duration of their dream

35
Q

Dement and Kleitman 1957- study 3

A

Subjects were woken when eye movement had occurred and eye direction was recorded - they were asked exactly what they had just dreamt

36
Q

Dement and Kleitman 1957- Results- Study 1

A

Significantly more dreams were reported in REM awakenings (80%) than non-REM sleep awakenings (9%)

37
Q

Dement and Kleitman 1957- Results - study 2

A

5 min period: in 75% of the awakenings participants were correct in matching the duration of their dream to the length of time they had shown in REM sleep
15 min period: in 63% of the awakenings participants were correct in matching the duration of their dream to the length of time they had shown REM sleep

38
Q

Dement and Kleitman 1957- Results - Study 3

A

Patterns of REMs and the content of dreams showed a relationship.
Vertical REM- was associated with dreams of looking up and down at cliff faces, ladders and basketball nets
Horizontal REM- was associated with dreams of two people throwing tomatoes at each other

39
Q

Dement and Kleitman 1957- Evaluation

A

-dreams are recalled easier in REM than non-REM sleep, perhaps dreams occur in deeper sleep but are more difficult to recall from it
-the study used a limited sample, mostly men, therefore showed a lack of generalisability
-lacked ecological validity as not in own home
+this was the first scientific (objective data collected) research into dreaming- before this the only research on dreams had been to ask participants about their experience of dreaming (subjective data)
+the research provides support for the idea that dreams can be studied in an objective way. This then opened up the subject for further research (eg sleep stages) and theories of sleep

40
Q

Oswalds restoration theory of sleep 1966- sleep restores the…

A

Brain and the body

  • NREM sleep restores and repairs physical damage that has happened through the day eg bruises, cuts, damaged tissues, bones, muscles by restoring depleted energy and reserves hormones
  • REM sleep replenishes and renews brain chemicals. Protein synthesis takes place during sleep which encourages brain cell growth. Chemicals such as adenosine are cleared from the brain
41
Q

Oswalds restoration theory of sleep 1966- Evidence

A
  • sleep deprivation
  • changes in sleep patterns over lifespan
  • sleep patterns following brain injury
  • sleep patterns and illness
  • sleep patterns after major periods of exercise
42
Q

Sleep deprivation

A

Studies of sleep deprivation show brain function deteriorates with sleep deprivation

43
Q

Changes in sleep pattern over lifespan

A

Babies spend 18 hrs every 24hrs asleep and half of this is REM. By the age of 5 this has fallen to about 8 hours sleep and only 2 in REM which then remains the same for the rest of life. Since the first 5 yrs are very important for brain development where a great deal of protein synthesis is necessary for cell growth it makes sense that a younger child would require far more REM sleep than an adult if REM is important for brain processes

44
Q

Sleep patterns following brain injury

A

People recovering from brain injury, ECT and drug withdrawal tend to spend more time in REM during recovery. The suggests that REM sleep is important for proper brain functioning

45
Q

Sleep patterns and illness

A

Total sleep time increases during periods of illness - sleep is therefore required for improved immune functioning. Therefore, NREM sleep restores biological processes that have been deteriorated

46
Q

Sleep patterns after major periods of exercise

A

A number of pieces of research have shown that excessive exercise increase the amount of time spent in NREM

47
Q

The effect of dream deprivation (REM sleep)- Dement (1960) - Aim
Research supporting the restoration theory

A

To observe the effects of REM sleep deprivation in the laboratory

48
Q

The effect of sleep deprivation- Dement (1960) - Procedure

A

Dement observed 8 men during sleep in a sleep laboratory for 4-7 days consecutively. Participants were woken whenever eye movements indicated REM sleep. After each awakening, participants were kept awake for a few minutes and then returned to sleep

49
Q

The effect of sleep deprivation- Dement (1960) - Results

A

First night average number of REM sleep awakenings was 12 times. Last night average number of REM sleep awakenings was 26 times

50
Q

The effect of sleep deprivation- Dement (1960) - Conclusion

A

There are behaviour changes after REM sleep deprivation - including irritability, increased anxiety, reduced concentration and mild personality changes. As REM sleep deprivation increased, the participants all increased their attempts to enter or achieve some REM sleep. A control condition showed that it was not sleep deprivation in general but specifically REM sleep deprivation

51
Q

Caffeine and sleep

A
  • adenosine binds to adenosine receptors
  • this binding causes drowsiness by slowing down nerve cell activity in the brain
  • to a nerve cell, caffeine looks like adenosine: caffeine binds to the adenosine receptor
  • however caffeine doenst slow down the cells activity like adenosine would
  • as a result the cell can no longer identify adenosine because caffeine is taking up all the receptors that adenosine would normally bind to
  • instead of slowing down because of the adenosine effect, the nerve cells speed up
52
Q

Light and sleep

A
  • artificial light from lightbulbs or screens acts as a zeitgeber, inhibiting the SCN from releasing melatonin when we want to sleep
  • the light from low energy lightbulbs and from phone or computer screens contains a large proportion of blue wavelengths, which have a stronger effect on melatonin than other wavelengths of lights
53
Q

Drake et al 2013- caffeine and sleep- Participants

A

12 adults healthy men and woman, all were normal sleepers who in their regular lives were moderate consumers of caffeine. Participants kept their normal sleep routines

54
Q

Drake et al 2013- caffeine and sleep- method

A

Lab experiment

55
Q

Drake et al 2013- caffeine and sleep- procedure + IV1 IV2 IV3 IV4

A

-Researchers tracked sleep by having participants keep sleep diaries and by using an at-home sleep app.
-participants were placed into three groups and given doses of caffeine in pill form at different times:
IV1- caffeine pill at bedtime
IV2- caffeine pill three hrs before bedtime
IV3- caffeine pill 6 hrs before bedtime
IV4- No caffeine

56
Q

Drake et al 2013- caffeine and sleep- results- mean total sleep

A
  1. caffeine at bedtime - 6.3 hours
  2. Caffeine 3 hrs before bedtime - 6.4 hours
  3. Caffeine 6 hrs before bedtime- 6.5 hours
  4. No caffeine during day- 7.7 hours
57
Q

Drake et al 2013- caffeine and sleep-results- sleep efficiency in %

A
  1. caffeine at bedtime - 82%
  2. Caffeine 3 hrs before bedtime - 82%
  3. Caffeine 6 hrs before bedtime- 82%
  4. No caffeine during day- 91%
58
Q

Drake et al 2013- caffeine and sleep-results- mean time taken to fall asleep

A
  1. caffeine at bedtime - 43mins
  2. Caffeine 3 hrs before bedtime - 37mins
  3. Caffeine 6 hrs before bedtime- 33mims
  4. No caffeine during day- 20mins
59
Q

Drake et al 2013- caffeine and sleep- conclusions

A
  • stick to a 2pm cut off for caffeine

- Taper caffeine as the day progresses

60
Q

The effect of blue light on sleep- Wiseman (2014)- method

A

A questionnaire

61
Q

The effect of blue light on sleep- Wiseman (2014)- procedure

A

A survey into the UK’s sleeping patterns. The survey asked about computer, tablet, smartphones and flat-screen television usage before bed.
It also asked respondents whether they used these devices in the two hours before going to bed

62
Q

The effect of blue light on sleep- Wiseman (2014)- results

A
  • Nearly 6 in 10 adults in Britain- more than 28 million people- are sleep deprived and get 6 hours or less each night.
  • 80% of respondents routinely use these devices in the 2 hours before bed. Among 18-24 yr olds this figure increases to 91%
63
Q

The effect of blue light on sleep- Wiseman (2014)- conclusions

A

Although any type of light stops you feeling sleepy, Research has shown that light towards blue light end of the spectrum is especially effective at keeping you awake because it suppresses the production of the sleep inducing hormone melatonin. Unfortunately, computer screens, tablets, smart phones, flat screen televisions, and LED lighting all emit large amounts of blue light, and so it’s important to avoid them before bedtime.

64
Q

The effect of blue light on sleep- Wiseman (2014)- implications

A
  • limit exposure to blue light in the few hours before going to bed
  • if you must use your smartphone, tablet or computer late in the evening, try turning down the brightness, ensuring that the device is at least 12 inches from your eyes, and using an app that dims the lighting on your screen at night
  • amber-tinted glasses that block blue light are highly effective at improving sleep quality and mood
65
Q

The impact of light from computer monitors on melatonin levels - Figuerio et al (2011)- participants

A

21 students from New York, all participants had normal vision.
They were divided randomly into three groups- 3 conditions of the IV

66
Q

The impact of light from computer monitors on melatonin levels - Figuerio et al (2011)- procedure + IV1 IV2 IV3 DV

A

-All used the same make of iPad in their own home one evening to read, play games, and watch movies from 11pm to 1pm
-each tablet was set to full brightness
IV1: these participants wore blue light goggles (these contained LED bulbs to blue enhance light exposure)
IV2: these participants wore orange-tinted goggles
IV3: these participants did not wear goggles
DV: Melatonin concentration measured in the saliva of the participants collected at 1.00am

67
Q

The impact of light from computer monitors on melatonin levels - Figuerio et al (2011)- results

A

After a two hour exposure there was suppression of melatonin levels in the saliva of participants in the clear goggle condition and the no goggle condition. But less suppression in the orange goggle condition.

Mean melatonin concentration at 1am for each condition

Melatonin concentration pg/ml with blue light goggles- 13

Melatonin concentration pg/ml with orange goggles- 31

Melatonin concentration pg/ml with no goggles - 17

68
Q

The impact of light from computer monitors on melatonin levels - Figuerio et al (2011)- conclusions

A
  • ‘manufacturers can use our model to determine how their products could affect the populations circadian rhythms, said Figuerio’
  • ‘we recommend dimming these devices at night as much as possible in order to minimise melatonin suppression, and limiting the amount of time spent using these devices prior to bedtime’
69
Q

Crick and Mitchison: Reorganisation theory of dreaming (1986)
What did crick and Mitchison propose?

A

Crick and Mitchison proposed that we have two types of information collected through the day which are stored in our memories

  1. Adaptive memories
  2. Parasitic memories
70
Q

Crick and Mitchison: Reorganisation theory of dreaming (1986)- adaptive memories

A
  • Adaptive memories are useful to us.
  • adaptive memories are the pieces of information we need to use.
  • for example where you saw your sister hide her huge bar of toblerone
71
Q

Crick and Mitchison: Reorganisation theory of dreaming (1986)- parasitic memories

A
  • parasitic memories are useless pieces of information we pick up during the day for example the colour of the shoes my mother in law was wearing
  • during REM, when we are dreaming, the brain is ‘off line’ (it’s not being used to process the moment to moment information needed while awake) and so uses this time to throw out all these parasitic - unwanted - memories from the day
  • dreams are a mechanism for unlearning unnecessary associations. Dreams with a pathological or harmful nature such as obsessions and delusions expel unwanted thoughts which If not got rid of could lead to obsessive or paranoid behaviour
  • we dream to forget - by discarding dreams, the dreamer becomes refreshed by making the adaptive - important - memories accessible
  • removing parasitic memories allows compact storage in our brains neutral networks without the danger of memory overlap caused by unwanted associations in the brain. This allows humans to have a smaller brain which processes information efficiently in selectively storing adaptive memories
  • REM allows smaller brains in mammals that dream than those that do not
72
Q

Crick and Mitchison: Reorganisation theory of dreaming (1986) - Evaluation

A

The following evidence supports it:
-the spiny anteater echidna and dolphins all have a very large forebrain relative to body sized they do not have REM sleep. This would explain this excessively large cortex because it does not lose unwanted memories during REM sleep so needs the capacity to store both adaptive and non adaptive memories
-Goertez (1997) The brain takes in +- 100 billion bits of information during a lifetime but is only able to store 100 thousand bits at any one time therefore there must be a process to discard irrelevant information
-there is evidence for a negative correlation between body size and total sleep - heavier animals need less sleep - and heavier animals have bigger brains.
——this theory supports the idea that information processing happens during sleep, specifically during REM sleep

73
Q

Crick and Mitchison: Reorganisation theory of dreaming (1986)- strengths and weaknesses

A

Strengths

  • explains why we have dreams in REM, why dreams are visual and why we forget our dreams.
  • Many useful applications
  • sleep deprivation studies support the reorganisation theory

Weaknesses

  • only explains functions of REM not, non REM.
  • How do we know what memories we should unlearn?
  • based o computer models of memory, not the real thing
  • lacks research on humans, dolphins research cannot be generalised to humans
  • conflicting with other researchers that increasingly agree sleep strengthens and consolidates memory
  • We remember some of our dreams that the theory doesn’t explain or account for
  • does not explain why dreams have a narrative
74
Q

Freud’s psychodynamic dream theory

A
  • Freud viewed dreams as wish fulfilment.
  • Freud suggested that our unconscious mind sometimes displays images in our dreams.
  • expressing these thoughts in manifest content protects us from distress because dreams represent unfulfilled wishes.
  • These wishes are disguised in dreams using defence mechanism such as symbolism and displacement which protect us from our true desires.
  • dreams demonstrate the aspects of (ID) thinking, which is illogical and lacking reality.
  • By analysing the manifest content dreams the hidden (ID) impulses or Latent content can be discovered.
  • A psychotherapist is able to help a client to decode the symbolism of the dream content. For example one of Freud’s clients was Anna O. Anna dreamt of killing a little white dog. Freud thought the dog was a displacement image for her sister-in-law who she hated. The dog was a defence mechanism to protect Anna from the terrifying reality that she wanted her sister-in-law dead.
  • the process of a therapist and client transforming manifest content into latent content is called dream work.
75
Q

Components to Czeisler et al study

A
  • aim 2x
  • method
  • participants
  • procedure
  • iv1
  • iv2
  • dv
  • results 3x
  • conclusion 3x
76
Q

Components of dement and kleitman study

A
  • aim + 3x
  • method
  • participants
  • procedure
  • study 1,2 and 3
  • results 1,2 and 3
  • evaluation
77
Q

The effect of alcohol on sleep- Ebrahim et al (2013)- Method

A

Meta analysis

78
Q

The effect of alcohol on sleep- Ebrahim et al (2013)- participants and IV1, IV2, DV, DV

A

A review of 27 studies (meta analysis) using over 2000 healthy volunteers studied in a sleep lab in 2 conditions:
IV1- after consuming no alcohol
IV2- consuming no alcohol
Dv- Time taken to fall asleep
DV- % of time spent in REM during whole night sleep

79
Q

alcohol and sleep- Ebrahim et al (2013)- results- with and without alcohol

A

With alcohol
Mean time to fall asleep- 4 mins
Mean percentage of REM sleep/night- 14%

Without alcohol
Mean time to fall asleep- 12 mins
Mean percentage of REM sleep/night- 23%

80
Q

Alcohol and sleep- effects of normal sleep- Ebrahim et al (2013)- conclusion

A

-alcohol does allow healthy people to fall asleep faster, although people who have consumed alcohol spend less time in REM sleep

81
Q

Alcohol and sleep explained

A