1. Sleep-wake cycle VCE PSYCHOLOGY UNIT 4 Presented by Kristy Kendall
Study design dot points:
changes to a person’s sleep-wake cycle and susceptibility to experiencing a circadian phase disorder, including sleep-wake shifts in adolescence, shift work and jet lag
the interventions to treat sleep disorders including cognitive behavioural therapy (with reference to insomnia) and bright light therapy (with reference to circadian phase disorders).

2. Image used under license from Shutterstock

3. Sleep-wake cycle

4. Owl or lark? Sleep quiz activity
Source: Pixabay

5. Sleep-wake cycle
Our bodies are tuned into a 24 hour sleep- wake cycle which is a regular circadian rhythm.
It is determined by an internal body clock located in the hypothalamus.
This clock also regulates our level of arousal, metabolism, body temperature and hormone secretions.

6. Circadian phase disorders
Sleep disruption due to alteration of the internal circadian rhythm.
Can be characterised by an inability to fall asleep or to remain asleep
Caused by a variety of reasons including:
lifestyle factors
genetics
shift work
jetlag
adolescence, etc..
Can result in:
insomnia
impairment in social and occupational functioning.
Source: Pixabay

7. Factors that effect the sleep-wake cycle
Lifestyle
Factors that effect the sleep-wake cycle
Shiftwork
Stressful or low stress job
Active or inactive lifestyle
Diet and health (stimulants)
Good sleepers are more likely to have a more regular sleep routine than poor sleepers.
Source:

8. Factors that effect the sleep-wake cycle
Genetics
Factors that effect the sleep-wake cycle
Studies found identical twins have more similar sleep patterns then fraternal twins.
Studies also suggest females tend to need more sleep than males.
Source: identical&page=1&position=0

9. Factors that effect the sleep-wake cycle
Jetlag
Factors that effect the sleep-wake cycle
Change of time zones
West is best…gaining and losing time
No attribution required:
Image purchased from:
Source: Shutterstock

10. Ways to help reduce jetlag
Factors that effect the sleep-wake cycle
Video source:

11. Factors that effect the sleep-wake cycle
Adolescence
Factors that effect the sleep-wake cycle
During adolescence the sleep/wake pattern shifts towards the evening (phase delay).
Also known as delayed sleep onset.
Particularly dangerous because adolescents need far more sleep than an adults
Why does delayed sleep onset occur?
Melatonin is a hormone that helps to induce sleep. During adolescence the release of this hormone is delayed for up to 2 hours.
Melatonin release is controlled by circadian rhythms but can also be effected by light.
It is also thought social factors can impact (e.g. homework demands, after school activities, internet).
No image attribution required

12. Impact of delayed sleep onset
Can create a vicious cycle…
This can lead to circadian phase disorder which causes extreme difficulty falling asleep and sleepiness when waking in the morning.

13. Treatment of circadian phase disorders
Light therapy can be used to re-set the body’s internal clock.
During light therapy your eyes are exposed to intense but safe amounts of light for a specific and regular length of time as artificial light may be used to affect the body clock in the same way that sunlight does.
Source: Pixabayz

14. 25 hour cycle?

15. Multiple choice activity
The sleep-wake cycle shift during adolescence is typically caused by A. depression and the sleep debt. B. delayed release of the hormone adrenaline. C. delayed release of the hormone melatonin. D. overproduction of the hormone melatonin.
(VCAA 2013 Exam Q19)

16. Multiple choice - response
The sleep-wake cycle shift during adolescence is typically caused by A. depression and the sleep debt. B. delayed release of the hormone adrenaline. C. delayed release of the hormone melatonin. D. overproduction of the hormone melatonin.
(VCAA 2013 Exam Q19)

17. Fast five: Question 1
What sort of rhythm is our sleep wake cycle on?

18. Question 1 (Response) What sort of rhythm is our sleep wake cycle on?
Answer:
Circadian

19. Fast five: Question 2
A shift from one country to another can result in negative effects known as _____________.

20. Question 2 (Response)
A shift from one country to another can result in negative effects known as _____________.
Answer:
Jetlag

21. Fast five: Question 3
T/F: Genetics can play a role in circadian phase disorders.

22. Question 3 (Response)
T/F: Genetics can play a role in circadian phase disorders.
Answer:
True

23. Fast five: Question 4
A delayed release of which hormone can cause delayed sleep onset in adolescence?

24. Question 4 (Response)
A delayed release of which hormone can cause delayed sleep onset in adolescence?
Answer:
Melatonin

25. Fast five: Question 5
A great way to reset the internal body clock is thought to be through ___________ therapy.

26. Question 5 (Response)
A great way to reset the internal body clock is thought to be through ___________ therapy.
Answer:
Light

27. Sleep-wake cycle VCE PSYCHOLOGY UNIT 4 Study design dot points:
changes to a person’s sleep-wake cycle and susceptibility to experiencing a circadian phase disorder, including sleep-wake shifts in adolescence, shift work and jet lag
the interventions to treat sleep disorders including cognitive behavioural therapy (with reference to insomnia) and bright light therapy (with reference to circadian phase disorders).

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