4: KKDP 9 Changes to the Sleep Cycle Flashcards
Circadian phase disorder:
A group of sleep disorders involving sleep disruption that is primarily due to a mismatch between an individual’s sleep-wake patterns and the pattern that is desired or required by the external environment.
Circadian Phase Disorder caused by (1):
Intrinsic factors (caused by the body) - Medical conditions and age related sleep wake shifts
Circadian Phase Disorder caused by (2):
Extrinsic factors (caused by the environment) - Shift work or travel changes
Circadian phase disorder symptoms:
- Difficulty falling asleep
- Waking frequently through the night
- Tiredness during the day
- Untreated can lead to sleep deprivation
First Circadian Disorder:
Sleep Wake Cycle Shift in Adolescents
Sleep-Wake Cycle Shift:
A period of high sleep disturbance for adolescents
Adolescents optimal sleep:
9 hours on average
Biological reason:
Delayed release (1-2 hours) of Melatonin and cortisol compared to when they were children. Thus wakefulness is also delayed.
Psychological reasons:
Adolescents like to exert their own independence, and it is common opinion early sleepers are ‘childish’
Social reasons:
Increased demands on time for socialising and school. School wakes up adolescents before they can get optimal sleep.
Effects:
- Insufficient sleep
- Sleep debt
- Lethargy/Fatigue
- Difficulties managing behaviours
Shift Work:
Involves work outside the period of a normal waking day.
Problem with shift work:
It disrupts the normal sleep-wake cycle, as it conflicts with our natural body clock, forcing people to be awake when they should be sleeping.
Symptoms of Shift Work:
- Difficulty falling asleep during the day
- Insomnia, chronic sleep deprivation and excessive sleepiness
Effects of Shift Work on the Sleep Wake Cycle:
- Distorted Sleep Timing
- Poor sleep quantity and quality
- Sleep deprivation
Jet Lag:
Shifting to a new time zone results in a mismatch between our internal circadian biological clock and the external environment.
Jet Lag occurs:
Because travel is quick, and our sleep-cycle remains aligned to the environmental time cues of the home time because there has been insufficient time to adjust to the time cues.
Why is travelling east worst?
Travelling in an easterly direction does not follow the sun, thus it is opposite to the environmental day-night cycle, so there is a greater mismatch between the circadian sleep-wake cycle of the external environment.
Effects of Jetlag:
- Difficulties initiating or maintaining sleep
- Excessive sleepiness
- Feelings of ‘malaise’; ‘not feeling right’
Minimising Jet Lag 1:
Start adjusting to the new time zone before you leave
Minimising Jet Lag 2:
Avoid stimulants such as coffee
Minimising Jet Lag 3:
Don’t sleep during the day
