Week 3

Question 1

What is sleep?

Answer 1

An altered state of consciousness characterised by:
Immobility
Reduced responsiveness
Fast reversibility to the awake state
Recurrence (fairly reliable on a 24hr cycle)

Question 2

What is a hypnogram?

Answer 2

Used to show the pattern of a night of sleep

Question 3

What does a typical hypnogram trace look like?

Answer 3

Start awake, progress to light sleep (N1) then deeper sleep brain slowing down (N2) then into deep sleep (N3) (hard to wake someone from deep sleep) then drift between N2 and REM

Question 4

What is REM sleep?

Answer 4

Rapid eye movement
Brain more active but muscles still immobile
Most likely to dream during this stage

Question 5

What is meant by sleep latency?

Answer 5

Period between trying to fall asleep and actually falling asleep

Question 6

What is meant by sleep duration?

Answer 6

How long in total one sleeps for

Question 7

What is meant by sleep disturbance?

Answer 7

How much time is spent awake during the night

Question 8

What is meant by sleep efficiency?

Answer 8

The proportion of time spent in bed that is actually asleep

Question 9

What is meant by sleep perceived quality?

Answer 9

Someone’s perception (subjective) of how they slept

Question 10

What is meant by sleep daytime dysfunction?

Answer 10

How sleepy someone feels the next day

Question 11

How can recall questionnaires be used to measure sleep?

Answer 11

Retrospective self-reported summary of sleep parameters (e.g. Pittsburg sleep quality index)

Question 12

How can a diary be used to measure sleep?

Answer 12

Prospective daily self reported measures/record of sleep parameters

Question 13

How can polysomnography be used to measure sleep?

Answer 13

Physiological measurements (e.g. Brain waves, eye/muscle activity, heart rhythm)

Question 14

How can actigraphy be used to measure sleep?

Answer 14

Wrist worn sensor of gross motor activity

Question 15

What are the characteristics of sleep hygiene?

Answer 15

Regular hours
Restful sleep environment 
Ensure comfortable bed 
Exercise regularly 
Consume less caffeine 
Don't over indulge on food/alcohol
Don't smoke 
Try to relax before bed

Question 16

What did a cross sectional survey of sleep of 1506 people in the US show?

Answer 16

Less active people have greater frequency of negative states e.g. disturbance/latency

Exercise associated with better sleep

Question 17

What are possible confounders of sleep quality?

Answer 17

Health status - someone healthy more likely to both sleep and exercise better

Lifestyle - people who exercise more are likely to have other healthy lifestyle factors

Stress - high stress often related to poor sleep and a feeling of not having time to exercise

Daylight - people who exercise more may get more outside time - impact of controlling sleep cycle

Question 18

What did meta analysis show about the effects of exercise on sleep?

Answer 18

Acute exercise has beneficial impacts on many objective indices of sleep, however these effects are small

Ceiling effect though - most likely done on already healthy sleepers so not much room for improvement so only small effects

Question 19

What is suggested about night time exercise and sleep?

Answer 19

Increased HR during first few hours of sleep then steadies

Didn’t actually impact sleep efficiency, same as control

Question 20

What is the circadian rhythm?

Answer 20

Internal biological clock

Controls appetite, sleep, body temperature and more

Question 21

What are the sleep chronotypes?

Answer 21

Refers to individual sleep cycle propensity
Dictated by circadian rhythm
Morning chronotype - advanced sleep cycle (larks)
Evening chronotype - delayed sleep cycle (owls)
Intermediate chronotype - flexible

Question 22

What is the DSM-V for insomnia?

Answer 22

Difficulty initiating or maintaining sleep or suffering from non restorative sleep for 3 or more days a week for at least 1 month.

Causing distress e.g. sleepiness, poor concentration, low mood or impaired social, occupational or other functioning.

Question 23

What are the personal and societal costs of insomnia?

Answer 23

Lower quality of life 
Lower productivity 
Higher absenteeism 
Accident rates 
Healthcare costs

Question 24

What were the results of the walking trial on 41 adults with chronic insomnia?

Answer 24

Home based walking - 30 min 5d/w - 67% reduction in insomnia symptoms

Exercise also led to a reduction in depression/anxiety