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).

3. Image used under license from Shutterstock

4. Sleep-wake cycle

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

6. 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.

7. Circadian phase disorders
Circadian phase disorders = shifts in our sleep–wake cycles. Cicadian rhythm disrupted
Circadian phase disorders result in disturbed sleep and consequential daytime sleepiness and, therefore, negatively affect a range of personal, work, school, social and safety aspects of life.
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

8. Factors that effect the sleep-wake cycle
Adolescence
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
In teenagers, the release of sleep–wake hormones such as melatonin at night (inducing sleepiness) and cortisol in the day (encouraging alertness) is often delayed
for up to 2 hours.
This means that the average bedtime of 9.30–10.30 p.m. is pushed back later and most teens report not being tired at this time.
A sleep time of p.m. and a wake time of 7.00 a.m. – perhaps typical of the school week – will leave a teenager at least one hour short of the optimal amount of sleep.
Over the period of one week, this adds up to a sleep debt of at least 5 hours. If this happens, teenagers can become chronically sleep deprived.
No image attribution required

9. 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, a myriad of electronic devices, social networking sites, television and playing sport late at night keep our brains stimulated and prevent sleep.

10. 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:

11. Shift work
Shift work disorders are probably the most problematic in terms of circadian phase disorders.
While the disruption to adolescent sleep patterns is largely due to internal
(biological, endogenous) factors, night shift disruptions are mainly caused by external (environmental, zeitgener) factors.
Working at night conflicts with our natural bodyclock, forcing people to be awake when they should be sleeping.
If the shift worker’s body clock cannot adjust, sleep is interrupted, which can result in chronic sleep deprivation, leading to excessive sleepiness, insomnia, or a host of other serious issues as already discussed.

12. 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

13. Factors that effect the sleep-wake cycle
Jetlag
jet lag occurs when travelling across time zones.
Our sleep–wake cycle is disrupted and we can find it difficult to adjust and function at our best in the new time zone.
This is particularly true when we travel in an easterly direction.
With a natural body clock of just over 24 hours, we find it easier to stay up (delay sleep) than to sleep earlier (advance sleep).
West is best…gaining in easier than losing time
No attribution required:
Image purchased from:
Source: Shutterstock

14. EG
If we hop on a plane in Melbourne at 4.00 p.m. (1.00 p.m. Perth time), we should arrive in Perth around 5.05 p.m. (8.05 p.m. Melbourne time)
We are likely to adjust to this new time zone quickly, as staying awake for longer is easier than going to bed earlier.
In other words, this change is more compatible with our natural circadian rhythm.
Going home is a different story! Leaving Perth at 4.00 p.m. (6.00 p.m. Melbourne
non-daylight savings time) lands you in Melbourne around 9.35 p.m. (7.35 p.m. Perth time).
The likelihood of being able to fall asleep quickly is reduced. We may experience some jet lag and take a bit longer to adjust.

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

16. 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.

17. 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.
Light therapy is administered in the morning to those who still want to sleep
bright light therapy in done in the evening in an attempt to delay sleep.
The bright light therapy signals to the brain’s suprachiasmatic nucleus that it is daylight, effectively acting as a zeitgener. This will cease the release of melatonin from the pineal gland.
Source: Pixabayz

18. 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)

19. 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)

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

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

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

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

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

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

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

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

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

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

30. Dysomnias and parasomnias
VCE PSYCHOLOGY UNIT 4
Dysomnias and parasomnias
Presented by Kristy Kendall
Study design dot point:
the distinction between dysomnias (including narcolepsy and sleep-onset insomnia) and parasomnias (including sleep apnoea and sleep walking) with reference to the effects on a person’s sleep-wake cycle
the interventions to treat sleep disorders including cognitive behavioural therapy (with reference to insomnia) and bright light therapy (with reference to circadian phase disorders).

31. Image used under license from Shutterstock

32. Sleep disorders
The term sleep disorder refers to any problem that disrupts the normal NREM – REM sleep cycle, including the onset of sleep.
If sleep phenomena such as dreams and walking and talking during sleep recur and disrupt sleep, then this is also considered to be a sleep disorder.
Dysomnias – a problem getting to sleep or staying asleep, or excessive sleepiness.
Parasomnias – Parasomnias are sleep disorders characterised by abnormal behaviours during sleep. There are many different types of parasomnias, some still being classified, including nightmares, sleep walking, sleep aggressions, sleep-related eating orders and the cessation of breathing during sleep.
Some parasomnias occur during REM sleep, others in NREM and others in the sleep–wake transitions

33. Dysomnia: Insomnia
Insomnia is a problem which involves continually getting insufficient sleep.
There are different types of insomnia that people may experience including:
> sleep-onset insomnia: trouble falling asleep at the beginning of the night
> sleep-maintaining insomnia: difficulty maintaining sleep
> early morning awakening insomnia: trouble with waking up too early and not being able to go back to sleep.
A failure to fall asleep within 30 minutes after intended time.
Awakening for more than 30 minutes during the night.
A consistently reduced amount of total sleep.
A complaint of poor sleep.
Feeling tired during the day.

34. Causes of insomnia Psychological causes of insomnia
Typical causes of short term insomnia are emotional or social disturbances including relationship problems, the death or serious illness of someone close, upcoming important events or major lifestyle changes.
Physiological causes of insomnia
 These may include medical problems, severe or persistent pain or excessive use of alcohol or other drugs that disrupt the sleep cycle.

35. Treating insomnia
Any of the techniques discussed regarding healthy sleep habits
Sleeping tablets
Cognitive behavioural therapy (CBT), CBT-I, shorthand for cognitive behavioural therapy to treat insomnia
substituting unwanted thoughts and behaviours with more desirable ones.
substituting thoughts, behaviours and habits that inhibit sleep
and replace with those that promote sleep
It assumes that our behaviors and cognitions (thoughts and
feelings) regarding sleep influence each other strongly.
It recognizes that we can get into a nasty cycle where poor
sleep behaviors lead to negative thoughts and emotions
about sleep, which then influence the poor sleep behaviors
further.

36. CBT for insomnia
Includes the use of meditation, relaxation and visual imagery
Effective in 70-80% of cases
Treats underlying cause behind insomnia
The duration of therapy time can be a disadvantage
Image used under license from Shutterstock

37. Dysomnia - Narcolepsy
Narcolepsy is a sleep disorder in which people experience sudden, excessive and uncontrollable onsets of daytime sleeping where they go from being awake straight into a period of REM sleep.
It does not matter how long the person slept the night before, the sleep attacks still occur.
It is often accompanied by:
cataplexy: characterized by a complete loss of muscle tone which causes the individual to collapse. This is consistent with the loss of muscle tone that we experience in REM sleep
vivid and frightening dreams
short period of paralysis after waking up
When people with narcolepsy go to sleep at night, their night sleep begins with REM sleep, rather than going through the traditional NREM stages prior to the first REM sleep
They often sleep around the same amount as the average person, but still experience extreme sleepiness during the day.
Narcolepsy, usually starts to appear in adolescence/early adulthood and may get worse.

38. Causes & treatments of narcolepsy
Most people with narcolepsy have low levels of the chemical hypocretin (a neuropeptide also known as orexin)that regulates sleep and wakefulness
Visual representation of hypocretin
You can treat narcolepsy through stimulants

39. Parasomnia – Sleep apnoea
Sleep Apnoea is a temporary suspension of breathing for short periods during sleep.
These periods can last from 30 seconds to two minutes and usually terminate with a loud snore, body jerk, arm fling or by sitting upright.
Can be caused by physical blockage , with the airways failing to open
Sleep apnoea is linked to chronic snoring
Image used under license from Wikipedia

40. Causes & treatments of sleep apnoea
Sleep apnoea has many and varied causes:
relaxation of muscles at the back of the neck that obstructs breathing
fatty tissue around the neck
failure of the breathing centres of the brain
Treatments:
Continuous Positive Airway Pressure (CPAP) This is a breathing mask is commonly used. It fits over the person’s mouth and nose and provides a continuous flow of air to keep their airways open. This stops the likelihood of the airway becoming blocked and therefore breathing from ceasing
oral appliances
Surgery (uvulopalatopharyngoplasty)
Weight loss
Trimmed uvula and soft palate
Tonsils removed
Image used under license from Wikipedia

41. Parasomnia: Sleep walking
Sleepwalking (somnambulism) involves walking whilst asleep and sometimes conducting routine activities.
Most commonly observed in children but can also occur in adults (usually at times of high stress).
Occurs in stage 3 or four of NREM sleep and can go on for up to half an hour (Usually between 5 and 15 minutes)
Watch this clip from the feature film Sleepwalk With Me
See Wikipedia page for more details on the film:
Image used under license from Freepik
Video source:

42. Comparing dysomnias with parasomnias