Chapter 7 (Changes To Sleep-Wake Cycle) Flashcards
sleep deprivation
- not getting enough sleep for a person of your age
partial: less than required amount of sleep with 24 hr
causes of partial sleep deprivation
- lifestyles factors
- sleep apnoea
- not going into deeper NREM
- medication
impacts of partial sleep deprivation - affective
- changes in emotional state and functioning
- tends to lead to quicker and more intense emotional response
e.g: emotional outbursts, less empathy, more aggressive
impacts of partial sleep deprivation - behavioural
- changes in action and way we function
e.g: physical changes, increased risk taking, reduced motor and hand-eye coordination, eating more, experience microsleep
impacts of partial sleep deprivation - cognitive
- refers to changing in thinking processes
e.g: lapses in attention, poor decision making, impaired learning, irrational thinking, difficulty completing automatic processes
sleep deprivation v B.A.C
- 17hrs wakefulness is compared to B.A.C of 0.05 - partial deprivation
- 24 hrs wakefulness is compared to B.A.C of 0.1 - full deprivation
- usually results in negative mood, increased B.A.C can either lead to positive or negative moods
circadian rhythm sleep disorders
- group of sleep disorders involving a mismatch between the actual and desired sleep wake pattern
- results in less sleep
delayed sleep phase syndrome
- delay in sleep onset resulting in going to sleep later and wake up later
- onset of sleep may be delayed by 2-3 hrs
- is the most common circadian rhythm
SYMPTOMS - sleep-onset insomnia - a person with DSPS cannot easily change their sleep pattern
- most common in adolescents (7-16%)
- result in on going partial sleep deprivation
possible causes of DSPS in adolescents
internal biological: due to puberty there is a hormone induced shift of the body clock with melatonin not being released until 1-2 hrs later than childhood
internal psychological: rumination (repeatedly worrying)
external: social factors (work, study, social commitments)
different rhythms
circadian rhythm - 24hr cycle
ultradian rhythm - less than 24hrs
advanced sleep phase syndrome
- early sleep onset resulting in going to sleep earlier and waking up earlier
- onset of sleep may be advanced by 2-3 hrs
- most common circadian phase disorder
SYMPTOMS - extreme tiredness in evening, early sleep onset, awakening early, tired during day, reduction in melatonin - a person with ASPS cannot easily change their sleep pattern
- common in older people, 1% of population
shift work
- involves employment outside normal 9-5 work day which disrupts natural circadian rhythm and sleep wake cycle
- people are forced to be awake when they are meant to sleep
IMPACTS - sleepiness at work, sleep deprivation, insomnia, mood swings
MINIMISE IMPACTS - shift friendly roster, bright light conditions, low light conditions
bright light therapy
- involves exposure in intense but safe amounts of light at regular patterns to shift individuals sleep wake cycles to desired schedule
- emits strong artificial light
- exposure to bright light earlier in the day
- exposure to minimal light before bed
- opposite approach for ASPS
sleep hygiene
- establish regular sleep onset and wake schedule
- minimise exposure to light before bed
- maximise light in the morning
- avoid napping
- avoid stimulants
zeitgebers
- environment time cues that provide signals to the brain (SCN) to regulate the body’s circadian rhythm
- helps promote sleepiness and wakefulness at appropriate times
- light is the strongest zeitgebers
- used by SCN to adjust circadian rhythm to 24hr day
daylight and bluelight
- exposure to sunlight helps ensure we are awake during the day and asleep at night
- blue light refers to light on the visible light spectrum with short waves lengths
- sun is the main source of bluelight
- is emitted through devices
- when this happens before bed the body gets conflicting information, some saying it’s time for bed while the bluelight is delaying the release of melatonin
temperature
EXTERNAL - air temperature, the ideal air temp fro sleep is around 16 degrees
INTERNAL - normal body temp is 37 degrees which can vary be 1 degree throughout 24 hrs
- bodys core temp follows a 24hr circadian rhythm in line with the sun
- drop in body temp starts around 2 hrs before sleep, coinciding with melatonin release
eating and drinking patterns
- sleep wake patterns can be influenced by what and when you eat and drink
- circadian rhythm prepares the body fro digestion of food during the day
TIPS - - maintain relatively stable eating and drinking pattern
- avoid food 3-4 hrs before bed
- avoid caffeine in the evening
- alcohol can lead to the onset of sleep but typically impairs sleep quality
