U4AOS1A - Demand for Sleep Flashcards
(73 cards)
1
Q
How is consciousness defined?
A
-
Awareness of the world around us and ourselves, including thoughts and feelings
- Internal or external
-
Varies along a continuum of awareness
- Total awareness (sustained attention)
- Complete lack of awareness (unconscious in deep coma or vegetative state)
2
Q
What are the contents of consciousness?
A
- What we are aware of at any given moment
3
Q
What is normal waking consciousness?
A
- Being awake and aware of…
- The external worlds
- Perception and thoughts
- Remaining aware of personal identity
- Percieving the world as real
- Maintaining a sense of time and place
- Most people spend around 2/3 of their day in this state
4
Q
What is an altered state of consciousness (ASC)?
A
- Any state of consciousness that is significantly different from NWC or any waking state in terms of level of awareness and experience
- Mental processing of internal and external stimulus shows distinguishable, measureable changes in areas such as…
- Content limitations - Information we choose to attend to and how much we can take in
- Self-control
- Inhibition
- Self-awareness
- Emotional awareness
- Perceptions of time, place and one’s surroundings
-
Types
- Naturally Occurring
- Induced
5
Q
Describe the types of ASC’s
A
-
Naturally Occurring
- In the course of our everyday activities without the need for aid or external influence
- E.g sleep, dreaming, daydreaming, cycles of wakefulness and drowsiness, fatigue
-
Induced
- Brought on through some sort of aid
- Intentional - meditation, hypnosis, alcohol ingestion, certain medication or drugs
- Unintentional - accident, disease or disorder
- Types are not mutually exclusive and a naturally occurring ASC like sleep can also be induced through tranquilisers and sleeping pills
6
Q
Define psychological construct
A
- An agreed upon concept that is ‘constructed’ to describe specific ‘psychological’ activity, or a pattern of activity that is believed to occur or exist but cannot be directly observed/measured
- Primarily based on research evidence
- Measured indirectly using
- Information provided by the individual
- Behaviour that is demonstrated
- Physiological changes that can be measured (such as recording brain activity)
7
Q
What is a hypnogram?
A
- A graph that represents the time period of each stage of sleep, and the transitions between these
- 1 1/2 hour cycles consist of NREM and REM
8
Q
Define sleep
A
- A regular and naturally occurring altered state of consciousness (ASC) that involves a loss of awareness and disengagement with internal and external stimuli
- Necessary for restoration and rejuvenation
- Full duration of sleep - Sleep episode
- Fundamental human need alongside nutrition and physical exercise (3 pillars of good health)
9
Q
What is REM?
A
-
Rapid eye movement sleep
- High levels of brain activity
- Low levels of physical activity
- Heart rate fast and irregular
- Blood pressure rises
-
Breathing is shallower, faster and irregular compared to NREM
- Sleeper looks relaxed
-
Occasional twitching in small muscles
- Most skeletal muscles are limp
- Appear paralysed
- Dreaming has narrative
-
Arousal threshold is variable
- May be like that of N2 or N3
10
Q
Why is REM sometimes referred to as paradoxical sleep?
A
- Contradictions in…
- Active brain in an apparently paralysed body
- Internally, brain and body are active; externally body appears calm and inactive/relaxed
11
Q
Is REM considered deep or light sleep?
A
- Depends on criteria
- Wakefulness - Light
- Lack of muscle activity - Deep
12
Q
What is NREM?
A
- Non-rapid eye movement sleep
- Type of sleep characterised by…
- Lack of rapid eye movement
- Has 3 stages with increasingly deeper sleep (N1, N2, N3)
13
Q
Describe Stage 1 of NREM sleep
A
- When sleep begins
- Relatively light sleep
-
Physiological
- Lower level of bodily arousal
- Decrease in heart rate, breathing, body temperature and muscle tension
- Slow, rolling eye movements
- Hypnic jerks (involuntary muscle twitches), similar to a spasm
- Can easily be awakened by a gentle nudge or sound
- Low arousal threshold
Arousal Threshold - How much it takes to wake up (similar to pain)
14
Q
Describe Stage 2 of NREM sleep
A
- Period of light/moderate sleep - Gradually becomes deeper
- First stage where you are completely asleep
- Continued slowing of heart rate, breathing, muscle activity and body movements
- Body temperature continues to fall
- Eye movements slow
- Brain waves slow further
-
Less easily disturbed compared to N1 and requires more stimuli
- But can still be easily aroused
15
Q
Describe Stage 3 of NREM sleep
A
- Deep sleep
- Heart rate and breathing slow to their lowest levels
- Muscles completely relaxed - Barely move
- Delta waves are predominant
-
Highest arousal threshold
- Difficult to awaken someone
- Harder than in any other stage
- If awoken (especially adruptly), they feel groggy and can take a few minutes to adjust - Referred to as ‘sleep inertia’
- May disappear as sleep progresses
16
Q
What are similarities between REM and NREM sleep?
A
- Naturally occurring
- Reduced awareness
17
Q
Distinguish between REM and NREM sleep (8)
A
- REM - Fast, jerky eye movement, NREM - Slow minimal eye movement
- REM - Beta brain waves (small), NREM - Delta
- REM - Paralysis, NREM - Movement is possible
- REM - Heart rate increases, NREM - Heart rate decreases
- REM - Dreaming, NREM - Generally no dreaming
- REM - Duration increases, NREM - Decreases
- REM - 20% of sleep, NREM - 80%
- REM - Replenishes mind, NREM - Replenishes body
18
Q
What is within each sleep episode?
A
-
Sleep cycles between rapid eye movement (REM) sleep and non-rapid eye movement (NREM)
- Each sleep cycle lasts around 90 minutes (ultradian)
- NREM periods tend to decrease as the night progresses, REM periods increase
19
Q
Distinguish between a sleep episode and sleep cycle
A
-
Sleep Cycle
- Sleep phase comprising NREM sleep and REM sleep
- Occurs within a sleep episode (and is normally repeated a number of times, depending on the duration of the sleep)
-
Sleep Episode
- Sleep event
- Starts with sleep onset and ending with a final awakening
- Comprises one or more sleep cycles (but not necessarily complete cycles)
20
Q
State how sleep cycles and episodes can be voluntary and involuntary
A
- Voluntary - Intentionally induced by medication
- Involuntary - Tiredness or fatigue
- Both cannot be prevented and can be interrupted
- Voluntary - Alarm Clock
- Involuntary - Arousal due to biological need for urination
21
Q
What are 4 types of brain waves?
Fish and Chips are good BATD (battered)
A
-
Beta
- Associated with alertness and intensive mental activity during NWC
- Also present when dreaming during a period of rapid eye movement sleep
-
Alpha
- Appears when you are awake and alert but mentally and physically relaxed and internally focused
-
Theta
- Most commonly produced when you are very drowsy - E.g falling asleep or just before waking
- Can also be produced when awake and engaged in creative activities
-
Delta
- Mostly associated with deep, dreamless sleep or unconsciousness
22
Q
State the frequency and amplitude of the 4 main brainwaves
A
-
Beta
- F - High
- A - Low
-
Alpha
- F - Med-High
- A - Low-Med
-
Theta
- F - Low-Med
- A - Med-High
-
Delta
- F - Low
- A - High
B x D, A x T Matching opposites
23
Q
What are psychological indicators that can be used to measure consciousness?
A
- Perceptual and cognitive distortions
- Emotional awareness
- Self control
- Time orientation
- Considered subjective - Based on or influenced by personal feelings, tastes or opinions
24
Q
What are physiological indicators that can be used to measure consciousness?
A
- Heart rate
- Body temperature
- Galvanic skin response
- Eye movement (EOG)
- Muscle movement (EMG)
- Brainwaves (EEG)
- Considered objective - Not influenced by personal feelings or opinions in considering or representing facts
25
What physiological measures can be used to determine consciousness?
## Footnote
x3 DARE
* **Electroencephalograph (EEG)** - Detects, amplifies and records electrical activity in the **brain**
* Only EEG has beta, alpha, theta and delta brain waves
* **Electromyograph (EMG)** - Detects, amplifies and records the electrical activity of the **body's muscles**
* **Electro-oculograph (EOG)**- Detects, amplifies and records electrical activity of the **muscles surrounding the eyes**
* Collect **quantitative, objective** data
* Ensure to always state **ELECTRICAL** activity
## Footnote
Must use full definition in responses referencing techniques
26
What is an advantage of using physiological measures to determine consciousness?
* **Precise observations and measurements** can be made during sleep **without actually waking the person**
27
What are limitations of an EEG?
* **Poorly measures** neural activity that occurs below the **outer layer** of the brain
* **Does not provide detailed information** about what **particular structure** is releasing output
* **Lengthy time** to **attach electrodes** to scalp
28
How do you interpret an electroencephalography (EEG)?
* **Amplitude** - How high/intense
* **Frequency** - How often
* How many **action potentials**
29
What activity would each objective means of measuring consciousness show during REM and NREM sleep?
* **EEG**
* REM - Beta-like BW
* NREM - Theta-Delta BW
* **EMG**
* REM - Paralysis, no movement
* NREM - Slow movement
* **EOG**
* REM - High activity
* NREM - Slow, rolling
30
What psychological measures can be used to determine consciousness?
## Footnote
DISCLAIMER - Presents both qualitative and quantitative
* **Sleep Diaries**
* Record containing **self-reported descriptions** from an indivdual about their **sleeping periods**
* Includes an **estimated time spent sleeping**
* Has **judgments** they might have about the **quality and nature of their sleep**
* **Video Monitoring**
* The use of camera and audio technologies to **record an individual as they sleep**
* **Both objective and subjective**
31
What is a sleep lab?
* A place where **people with and without a sleep problem or disorder can be studied for research purposes**
* Individuals **with a sleep problem may also be observed, diagnosed and treated**
* **Artificial** environment
32
What are limitations of a sleep laboratory?
* **Artificial** environment → Data may be inauthentic
* EEG, EOG & EMG may bring **discomfort**
* Individual may be **self conscious** due to monitoring
* Sleep may be **intentionally interrupted** by researchers for the purposes of studying sleep patterns
33
What are the uses of a sleep diary?
* Provides **insights** that **can only be gained from the individual** themself
34
What are the advantages of a sleep diary?
* Can't obtain the specific data in any other way
* Non-intrusive
* Cost-Effective
* Does not require specialised equipment
35
What are the disadvantages of a sleep diary?
* Extremely **subjective**
* Individuals may be **ashamed to be completely honest**
* Requires compliance
36
What are the uses of video monitoring?
* Able to see things like...
* Sleepwalking
* If someone gets up a lot during their sleep
* If they toss and turn more than usual
37
What are the advantages of video monitoring?
* In their own home, not a sleep lab - **Natural** and **non-obtrusive**
* Can be a valuable tool for **children** who have **trouble verbalising their experience**
* Too young to complete a sleep diary
* More valid to measure **sleep quantity**
* Useful in **uncovering sleep disturbances** the individual may not rememeber (sleep walking)
38
What is a disadvantage of video monitoring?
* Don't know reasoning behind behaviour
39
Define biological rhythms
* **Repeated natural biological processes** that are **regulated by internal mechanisms**
* Cyclical
* Two types
* Circadian
* Ultradian
40
Define biological clock
* **Innate timing mechanism** that **regulates** the cycle of a **biological rhythm**
* Functioning is **genetically determined** and occurs at the cellular level
* **Level of melatonin indicates state** of body clock
* **SCN** is a notable example
41
Define circadian rhythms
* **Biological processes** that occur as part of a **cycle that lasts 24 hours**
* **Coordinate timing** of **activity of body systems**
* Allow for **optimised functioning** at **certain time** points
* Relate to **presence of light and dark**
42
Define *endo*genous
* Orginating **within an organism**
43
Define *exo*genous
* Originating **outside an organism**
44
What are criteria that can be used to classify a biological rhythm as a circadian rhythm?
* **Duration of 24 hours**
* **Repeats** every 24 hours
* **Persists** in the **absence of external cues** (endogenous)
* Can **adjust** to **match new external cues** (entrainable)
* Controlled/regulated by a **biological clock**
45
Define ultradian rhythms
* **Biological processes** that are **repeated** within **cycles that last less than 24 hours** - Sleep cycle is a type (90 minutes of REM and NREM)
* Other examples include...
* Digestion
* Heart rate
* Appetite
* Arousal
46
Distinguish between circadian and ultradian rhythms
* Circadian are **24 hours**
* Ultradian are **less than 24 hours**
47
Define sleep-wake cycle
* **24-hour cycle** that is made up of **time spent sleeping and time spent awake and alert**
* Type of **circadian** rhythm (with **ultradian rhythm occuring within**)
* Determined by **internal body clock** located in the **hypothalamus**
* Also regulates our level of body temperature and hormone secretions
48
Define melatonin
* **Hormone** released by the **pineal gland** to **induce sleep** as part of the **sleep-wake cycle**
* Typically at **night time**
* **Low levels of light**
* Helps to **sync internal events to external cues**
* Therefore **regulates circadian rhythm** and **syncs sleep-wake cycle to night and day**
* Amount of **light** influences **how much** is released
* **Artificial light** can **inhibit the release** (smartphones, tablets and other electronic devices)
49
How is melatonin released?
* **Lack of light** is **detected by the eye**
* Stimulates **suprachiasmatic nucleus** (SCN)
* The **SCN signals the pineal gland in the hypothalamus to release melatonin**
## Footnote
🔗 - Serotonin involved in making melatonin
50
What is the suprachiasmatic nucleus?
* **Double nucleated structure in hypothalamus** that **regulates** an individual's **sleep-wake patterns**
* Regulates by sending **neuronal messages** to the **pineal gland** to **secrete more/less melatonin**
* When **light** is detected **from the eyes**, the SCN also...
* Increases **body temperature**
* Releases **cortisol** to promote alertness and other arousal activities
* **Master biological clock**
* Influenced by **zietgebers**
## Footnote
Zietgebers - External cues
51
What would happen if the SCN was intentionally destroyed?
* **Circadian rhythms** and cyclical behaviours are likely to become **completely disorganised** or **dysfunctional**
52
What is the pineal gland?
* A gland in the brain **responsible** for the **production and release of melatonin**
53
Explain from a biological perspective why digital media use for a prolonged period before sleeping can affect sleep onset
* Artificial lighting can **mimic natural lighting**
* SCN uses **lighting as an external cue** to **signal** to the **pineal gland to inhibit the release of melatonin**
* Therefore in the **presence of a device** the **natural time for melatonin to be released is delayed**
* Causes **sleep onset to occur later**
54
Define sleep onset
* **Transition period** from being **awake** to being **asleep**
* **Length of time** to transition is **sleep latency**
55
What is the restoration theory?
* Theory that explains **why** we have the need to sleep
* Underpinned by the belief the sleep is needed for the **body to replenish its resources**
56
Do newborns have a different NREM to REM ratio? Why?
* Instead of 80/20, they have **50/50**
* This is because it **boosts brain growth and development**
* Important because they have **rapid brain development**
* Changes to 80/20 around 3 years of age
57
What are 4 reasons that adolescents have inadequate amounts of sleep?
* Poor sleep habits
* Hormonal changes
* Exposure to blue light
* Busy schedules
58
How can sleep debt accrue over time?
* If the body **continues to get poor quality or insufficient amounts** of sleep
* As sleep debt builds, **body and brain functioning begin to deteriorate**
59
Can you get rid of sleep debt?
* Yes
* Through **one night of uninterrupted sleep**
60
What are six prominent changes to sleep that appear as we age?
* From birth onward **total gradually decreases**
* Time spent in **REM decreases during the first 2 years** and remains **stable until old age**
* **N3 decreases**, **replaced** mostly by **N2**
* **Circadian phase delay in adolescence** (prefer going to **sleep later**)
* **After adolescence**, shift in circadian phase - **Sleep earlier**
* **Awakenings** in sleep **increase from adulthood to old age**
61
Why might an infant only have one or two cycles in a sleep episode?
* Their circadian rhythms are **not** yet **fully developed/ synchronised** with the **day-night cycle**
62
What is a biological reason that adolescents tend to get less sleep than they need?
* There is a biologically driven change in their sleep-wake cycle that **delays sleep onset for 1-2 hours**
63
Do sleep needs decline with age?
## Footnote
In order words, do sleep requirements decline with age?
* No
* Remains **constant through adulthood**
* Misconception due to the fact that as adults get older...
* They tend to have a **harder time falling asleep**
* Sleep **lightly**
* **Wake up more often**
* Spend **less time in deep, refreshing sleep**
* Have a **higher chance of developing a sleep disorder** (sleep apnea, insomnia)
64
Describe the distinguishing features of an **infant's** sleep
* Total **16 hours in first month**
* **Fragmented** due to feeding and nuturing
* Reduces to **12-13 hours by age 2**
* **50% REM reducing to 25% at around age 2**
* **Sleep onset initially REM**
* Normalises at around 2 or 3 months with maturation (circadian rhythm)
* **12 months** - Majority of sleep as a **single episode in the evening**
* Daytime napping common☺
65
Describe the distinguishing features of a **child's** sleep
* Sleeps **less than infants and more than adolescents**
* Approximately **11 hours**
* **Proportion of REM** sleep continues to **decrease**
* About half NREM is N3/N4
* Decreases markedly from about age 10
* Daytime napping decreases (especially at school age)
66
Describe the distinguishing features of an **adolescent's** sleep
* Total sleep **continues to decrease**
* Approximately **9 hours**
* Tendency to have **less than required** amount of total sleep
* Sleep-wake cycle shift **delays sleep onset by 1-2 hours**
* **Proportion of REM continues to decrease**
* **Mid-adolescence** sleep episode **begins to resemble young adults**
* N3/N4 progressively declines
* N2 increases
67
Describe the distinguishing features of an **adult's** sleep
* Total sleep time is averaged at about **8 hours per night**
* **NREM 75-80%; REM 20-25%**
* **Gradual decline** in...
* **Total** sleep time
* Time spent in **NREM and REM**
* **N3/N4** with **eventual loss**
* **Increase** in **sleep latency** and **awakenings**
68
Describe the distinguishing features of an **elderly person's** sleep
* **Decreases** through old age to **about 6 hours**
* NREM and REM continue to decrease
* **Little to none of N3**
* Tendencies of...
* More **fragmented sleep**/ night **awakenings**
* Becoming **sleepier in the early evening**
* **Waking earlier** compared to younger adults
* **Sleep disorders** more common
69
At what age does the proportion of REM sleep stabilise?
* **6** years old
* **REM takes up 20%**
* Remains **stable** over the rest of the life span
70
Explain the importance of light in regulating the circadian rhythm
* **Without external cues** the **circadian rhythm runs slightly longer than 24 hours**
* Exposure to **regular light** through the **consistent day-night cycle** helps to **reset a person's circadian rhythm to exactly 24 hours**
* Makes the **internal rhythm in line with the external environment**
71
When does sleep onset begin at NREM?
* By **3 months** it changes from beginning at REM to beginning at NREM
* This is because **at birth** the **circadian rhythm**...
* Has **yet to fully develop**
* Has **not synced with external cues** (zietgebers) of light/dark cycle
72
What is the purpose of light/moderate sleep?
* About **half of a total sleep episode** is spent in **N2** (NREM)
* Evolutionary purpose for **safety**
* Allows us to **wake** in **response to potential threats**
73
Compare the sleep-wake cycle of an adolescent to an adult
* Adolescents have their **sleep onset delayed by 1-2 hours**
* Goes to bed later than an adult
* Adolescents **need more sleep** than an adult
* **Wake up later** than an adult
