U4AOS1B - Changes to Sleep & Involvement in Mental Health Flashcards
What is a sleep disturbance?
- Any disruption to an individual’s normal sleep-wake cycle
- E.g Problems w/ sleep onset, waking from sleep
- Can be temporary, occasional or persistent
Define sleep deprivation
- Inadequate quantity and/or quality of sleep
- Can be partial or full
What is partial sleep deprivation?
- Having some sleep in a 24-hour period
- If persists for a long time, sleep debt may build
- Not getting enough to meet your needs in either…
- Quantity
- Quality
What is sleep debt?
- Accumulated amount of sleep loss from insufficient sleep
- E.g 40 minutes less than required for 4 days = 160 minutes of sleep debt
Show sleep debt in a formula
- Optimal sleep quantity per night - Total sleep quantity per night = Sleep Debt
How can sleep quality be measured objectively?
- Amount of awakenings experienced within a sleep episode
What is full sleep deprivation?
- Going without sleep for at least a 24-hour period
- One night or several in a row
State physiological effects of being sleep deprived
- Fatigue
- Trembling hands
- Drooping eyelids + Staring and inability to focus the eyes
- Slurred speech
- Lack of energy
- ⬆️ Pain Sensitivity
- Headaches
State psychological effects of being sleep deprived
ABC
-
Affective → Emotions
- Mood changes
- ★ Heightened anxiety
- ★ Depression
- Irritability/ Short temper
- Lack of Motivation
-
Behavioural → Actions & Controlling them
- ★ Slower reaction times
- Clumsiness
- ★ Risk-taking behaviours
- Changes to eating habits
- Sleep inertia
- Microsleeps
-
Cognitive → Mental processes
- ★ Lack of Concentration & Attention
- Impaired memory → Trouble with encoding, not retrieval
- Illogical/ irrational thoughts → ★ Poor decision making
- Trouble with simple, monotonous tasks → Complex not clearly impacted
Complex tasks are still impacted - Just not as noticably
Distinguish between the effects of partial (chronic) and full (acute) sleep deprivation
Differences and Similarities
- Partial
- Prolonged period of less than required sleep
- Chronic (Long Term) Symptoms
- Diabetes
- Stroke
- Heart diseases
- Depression
- Lowered immunity
- Full
- Acute (immediate) symptoms of hallucinations
- Similarities
- Cognitive, behavioural and affective
- Effects are reversible → Good habits + Sleep returns
- Both have severe effects
When partially sleep deprived, why is it more difficult to complete simple tasks in comparison to complex ones?
- In a normal situation simple tasks already do not require a lot of attention
- Use of divided attention → Doing tasks simultaneously
- When partially sleep deprived, attention is impaired
- Causing the already small amount of attention to be depleted further
- Complex tasks are still affected, but it is not as noticable
- This is because we often pay full attention to those tasks
- Meaning that the impaired attention caused by sleep deprivation is not as prominent
What is the difference between cognitive and behavioural effects?
- Cognitive - Mental processes
- Behavioural - Observable actions and behaviours
What is sleep inertia?
- Temporary, degressive period of reduced alertness and performance impairment (reaction time & cognition)
- Occurs immediately after awakening
- Groggy, partly awake and disoriented
Is an individual experiencing sleep inertia considered awake?
- It is a sleep-wake transition
- Individual is considered waking, partly awake or awake until it fully dissipates and the person reaches full alertness
What does being fully sleep deprived entail?
- More severe symptoms
- Physical and psychological effects are detrimental → Can potentially lead to death
-
Few days without sleep
- Sleep deprivation psychosis → Depersonalisation (loss of personal identity) & difficulty coping
- Hallucinations → Only some will experience, exclusive to full SD
-
Long-term effects
- Unlikely to experience any - Evident in Randy Gardner staying up for 12 days, able to recover after sleeping in for a few days
Briefly summarise an experiment in relation to cognitive effects of full SD
(D & R)
- Dawson and Reid
- 40 participants - Within subjects with counterbalancing
- 1 → Kept awake for 28 hours and assessed on cognition & concentration every 30 minutes
- 2 → Consume alcohol until 0.10% BAC is reached “
- Hypothesised that 24 hours without sleep will produce the same effects as 0.10% BAC
- Limited because it does not consider mood (may affect results)
Don’t think this will be assessed but it is helpful to know a practical example of sleep deprivation and BAC being compared
What are microsleeps?
- When sleep deprived body still wants to sleep
- Short sharp bursts of sleep → 3-15 seconds
- Individual appears to be awake (blank expression) and may be unaware that they have slept
- EEG patterns resemble N1/N2
- Associated with risk-taking behaviour → Pedestrian behaviour
What role does adenosine have in sleep?
Not required knowledge → Curiousity purposes!
- During day-time body breaks down energy sources
- Adenosine is one of the by-products
- As it builds up, it increases the urge to sleep → Sleep Pressure
- If not cleared away along with other waste products, it begins to overload the brain causing sleep deprivation
What does the glymphatic system do?
Not required knowledge → Curiousity purposes!
- More active during sleep
- Responsible for cleaning up the waste products made by using energy sources in the brain
- Uses cerebrospinal fluid to flush away
What happens if REM sleep is missed?
-
REM rebound may occur
- Bodies need to catch up in REM sleep in particular
- Typical proportion of REM to NREM may shift
- Dream intensity tends to increase
How do 17 hours of sleeplessness compare to BAC?
- Has same effects as 0.05% BAC
How do 24 hours of sleeplessness compare to BAC?
- Has same effects as 0.10% BAC
What affective effects do sleep deprivation and BAC have in common?
- Alter someone’s usual emotional state → More restless and irritable
- Impaired emotional regulation → Reactions enhanced
- Moodiness
What cognitive effects do sleep deprivation and BAC have in common?
- Decreased concentration & attention
- Impaired reasoning & complex thought
What are circadian rhythm sleep disorders?
- Group of sleep disorders involving sleep disturbance primarily due to a mismatch between an individuals’ sleep-wake pattern and the pattern that is desired
Must write mismatch to ‘desired pattern’
How can a sleep disturbance become a sleep disorder?
- Persistent and regularly disrupts sleep → Lead to distress
What is DSPS?
- Delayed sleep phase syndrome
- Internal circardian rhythm delayed 2+ hours despite having external cues (night → dark)
- Sleep and wake up later
-
Causes
- Lifestyle
- Poor habits
- Shift work
- Jetlag
- Adolescence → Hormones
Specify later/ delay in definition
What is sleep onset insomnia?
- Difficulty falling asleep despite having adequate time and opportunity to do so
- If attempt is made to go to sleep earlier, they may spend time awake tossing and turning because body clock has adjusted to later times
- Cause anxious or stressful thoughts → Worsen insomnia
- Unable to wake at desired/ necessary time spontaneously
- Need assistance of alarm or another external stimulus
- Feel sleepy for long period
Commonly experienced by people with DSPS
- Insomnia treated with CBT
Why is DSPS more common in adolescence?
- During adolescence melatonin release is delayed for up to 2 hours
- Lifestyle factors
- Homework
- After school activities/ extracurriculars
- Exposure to blue light
- Made worse by early school start times
Affects both females and males equally
State 2 biological reasons why adolescents may develop DSPS
- Biological delay in release of melatonin as a result of being an adolescent
- Use of blue light → Alter functioning of biological clock - Delay melatonin further
What is ASPD?
- Advanced sleep phase disorder
- Internal circadian rhythm signals sleepiness earlier than conventional times
- Sleep and wake earlier
-
Causes
- Lifestyle
- Genetics
- Shift work
- Jetlag
- Old age
Specify earlier in definition
What are symptoms of ASPD?
- Mismatch between sleep-wake cycle and environmental day-night cycle
- Compelling evening sleepiness
- Excessive daytime sleepiness
- Early morning insomnia after waking
Don’t use misalignment…
Why is shift work important to consider in relation to sleep?
- Not a sleep disorder but a cause of irregular sleeping
- Characterised by work conducted outside of regular waking hours → E.g Overnight
- Can be undertaken at varying times and can change regularly → Cause sleep-wake cycle to adjust frequently
- Should be scheduled to move forward in time from previous shifts (as circadian rhythm is 25 hours)
-
Symptoms
- Sleep-onset insomnia
- Sleepiness when needing to be awake and alert
Required to be awake when body wants to sleep + vice versa
How does shift work affect sleep timing, quantity and quality?
- Timing
- Scheduled outside normal/habitual sleep hours → Change in sleep onset time
- Quantity and Quality
- Changes too quick in the roster (especially if a consecutive shift is earlier than the previous - ‘backward in time’) will impact the cycle
- Need to adjust to schedule instead of being aligned to day-night cycle & other external cues
What does a ‘shift-friendly’ roster look like in relation to sleep?
-
Fixed Schedule
- Same shifts on a regular, ongoing basis → Ideally day
-
Rotating Schedule
- Change shifts after longer periods
- Successive periods are at a later time (aligned with 25 hour sleep-wake cycle)
NOTE - Rotating Schedules are more likely than Fixed to be harmful
→ When inconsistent and going ‘backwards in time’
What sleep-related challenge can a shift worker experience? How can this be combatted?
- Needing to sleep when it is still light outside
- Misalignment with day-night cycle due to assigned shifts
- Can be resolved through usage of block-out blinds and/or an eyemask when needing to sleep
How are circadian rhythm disorders treated?
-
Bright Light Therapy (BLT)
- Adjust circadian rhythm to a desired schedule by exposure to high-intensity light source
- Reduces release of melatonin → Enhances neurotransmission
- Reset → 15 minutes-2 hour exposure in the morning (DSPS), early evening (ASPD) or right before a shift (shift work) to stimulate wakefulness when it is needed and to cause sleepiness at a later time
- Can be used in addition to anti-depressants
What are the conditions needed for bright light therapy to be effective?
- Light must be at the right intensity
- Intensity needs to be built up over time to avoid headaches
- Used at the right time
- Used for the right amount of time
- Safe exposure → Person should not look directly at the light
What is seasonal affective disorder?
Not really required knowledge
- Type of depression caused by the change in seasons
- Not enough light in winter, manic in spring due to excessive light
- Prevalent in people who live in countries with short days → People have very low exposure to natural light during waking hours
What are zeitgebers?
- External time cues that help synchronise our internal body clock with the natural environment
- Strongest…
- Light (main)
- Temperature
- Eating and drinking patterns
- Exercise and socialisation
In questions that ask if _ is a zeitgeber, define zeitgeber
What is entrainment?
- SCN adjusting or resetting the sleep-wake cycle to match the environmental day-night cycle through the influence of a zietgeber
What are effects that light can have as a zeitgeber?
Helpful Vs Harmful
- Includes daylight - natural, and bluelight - natural or artificial → Biggest Impact
- Allow SCN to reset every 24 hours
-
Helpful
- Improves mood
- Memory
- Alertness
-
Harmful
- Impact sleep cycle
- Lead to eye strain
- Variables of… influence effects of light
- Intensity
- Type of light
- Time of exposure
- Length of exposure
What effects can different timings of daylight exposure have on the sleep-wake cycle?
- Morning and Early afternoon
- Advances
- Sleep and wake earlier
- Late afternoon and Early evening
- Delays
- Sleep and wake later
Does not have to be direct exposure
Describe the relevance of blue light in relation to the sleep-wake cycle
- Helpful in staying alert by suppressing melatonin during the day, but unhelpful at night → Prevents sleeping
- Low intensity blue light from devices in the evening = Same effects as more sun bluelight
- Reduces/ delays natural melatonin production
- Effects are more severe if active E.g texting & gaming
- Even with a ‘night-mode’ on, stimulation from devices can still affect sleep
Does closing your eyes block enough light for the SCN to use it as a cue?
- No
- Eyelids cannot block sufficient light to suppress melatonin and prevent a sleep phase shift
- Circadian rhythm can be affected even with very low levels of indoor light and closed eyes → Skin is very thin!
- Can be combated through wearing an eye mask → May improve sleep quality
What are effects that temperature can have as a zeitgeber?
- Body temperature cools when we sleep
- Studies suggest → Sleeping in a cooler (but not cold) room assists the body in getting to its ideal temperature for optimal sleep
- Around 18 degrees, varies within individuals
-
Core body temperature can be decreased at bedtime if you take a warm bath or shower prior to (but not immediately before) sleeping
- Body temperature will decrease after leaving bath/shower to adapt to cooler environment
- Promotes shorter sleep onset → Relaxation
- Longer initial sleep cycles
- More N3
Zeitgeber is not body temperature but room temperature → External cue
What are the effects eating and drinking patterns can have as a zeitgeber?
- Entire eating and drinking pattern needs to be aligned with desired sleep-wake cycle
- Has to be maintained in a stable way
- Erratic patterns with variable meal and snack times have detrimental effects on the sleep-wake cycle
- Food can be disruptive just before sleep
- Harder to fall asleep with a full stomach → Ready to digest during the day but not at night
- Harmful to sleep feeling hungry → Poorer sleep quality and quantity
- Thus a consistent pattern must be maintained
What are the effects of caffeine, alcohol, sugary and spicy foods as zeitgebers?
-
Caffeine
- Stimulate CNS ⬆️🫀, ⬇️😴 (melatonin)
- Body takes 4-6 hours to break down
-
Alcohol
- Induce drowsiness + Assist sleep onset
- However can shorten overall sleep duration and quality (2nd half) → Awakenings, nightmares, diuretic (wake to use bathroom)
-
Sugary Foods
- Negative impact on sleep quality and quantity
-
Spicy Foods
- Increase body temperature → Delay/ impair sleep
- Stimulate and increase metabolic processes → More difficult to fall asleep
What is sleep hygiene?
- Practices and habits that promote an individual’s sleep patterns
What does good sleep hygiene look like?
- Regular sleeping schedule
- Associating bed & bedroom w/ sleep
-
Avoiding stimulation before bed
- Blue light & activity with devices
- If cannot sleep then get up
- No napping during normal waking period
-
Avoiding stimulants
- Caffeine
-
Exercise for at least 20 minutes
- But not too close to bedtime
-
Eating in alignment with day-night
- Breakfast - Lunch - Dinner
- Comfortable sleeping environment
- Adequate exposure to natural light throughout day
How can sleep hygiene and zeitgebers worsen ASPD?
- Sleep hygiene → Practices during wakefulness that impact ability to fall asleep @ desirable time
- Zeitgebers → Environmental cues that affect SWC
- Large meals early in the morning (SH) + Darkness & lack of meals in late afternoon and early evening (Z) ★ Trigger early onset of sleep
How are sleep and wellbeing related?
- Better sleep ⬆️ Mental Wellbeing
- Low quality/quantity of sleep ⬇️ Mental Wellbeing
- Concentration problems
- Impulse control issues
- Depression
- Anxiety
- Aggression
How quickly and how well do people usually recover from the effects of partial sleep deprivation?
- Depends on the amount of sleep debt accrued
-
Occassionally/ short-term basis
- Minor and temporary
- Quickly recover when sleep debt is repaid → One night of good sleep
-
Successive nights of inadequate sleep
- Sleep debt accummulates and effects multiply → Will take longer to recover
