The Science of Sleep

Question 1

Circadian Rhythm

Answer 1

• Cyclical changes that occur on a roughly 24-hour basis in many biological processes
• Regulated by the Suprachiasmatic Nucleus (SCN)

Question 2

Suprachiasmatic Nucleus (SCN)

Answer 2

• Located in the hypothalamus
• Brain’s “Biological clock”
• Pineal gland releases a hormone called melatonin

Question 3

How much sleep do we need?

Answer 3

An average person requires 7-10 hours per night

Question 4

Amount of sleep needed depends on….

Answer 4

• Age
• Health
• Quality of Sleep
• Genetics
• Species

Question 5

Sleep deprivation can result in…

Answer 5

• Difficulties learning
• Poor attention
• Lethargy

Question 6

Sleep deprivation is associated with various adverse health outcomes…

Answer 6

• Weight gain
• Diabetes
• Heart problems
• Weakened immune systems

Question 7

Stages of Sleep

Answer 7

• Awake and Alert
• Calm Wakefulness
• Stage 1
• Stage 2
• Stage 3 & 4
• Stage 5 (REM sleep)

Question 8

Awake and Alert

Answer 8

• Beta waves ( approx. > 13 waves per second )

Question 9

Calm wakefulness

Answer 9

• Alpha waves ( approx. 8-12 waves per second )

Question 10

Stage 1

Answer 10

• Theta waves ( 4-7 waves per second )
• Myoclonic jerks
• Hypnagogic imagery

Question 11

Stage 2

Answer 11

• Sleep Spindles: Short burst of neural activity
• K-Complexes: A large waveform that occurs intermittently

Question 12

Stages 3 & 4

Answer 12

• Delta waves (1-2 waves per second)
• Stage 3 < 50% of waves are delta
• Stage 4 > 50% of waves are delta
• “Deep sleep” is required for feeling well rested
• Time spent in deep sleep declines with age

Question 13

Stage 5 (REM sleep):

Answer 13

• Rapid eye movement (REM): Darting of the eyes underneath closed eyelids during sleep
• Stage of sleep during which the brain is most active and during which vivid dreams occur most often. Rebounds when REM sleep is lost

Question 14

Non-REM sleep (NREM)

Answer 14

Stages 1-4 of the sleep cycle during which rapid eye movements (REM) do not occur and dreaming is less frequent and vivid

Question 15

Insomnia

Answer 15

• Difficulty falling and STAYING asleep.
  ~ Regularly takes more than 30 minutes to fall asleep
  ~ Waking up too early in the morning
  ~ Waking up during the night and having trouble returning to sleep
  ~ Factors such as age, drug use, exercise, mental status, and bedtime routines may contribute to insomnia

Question 16

Behavioural Treatment for Insomnia

Answer 16

• Make sure to have a consistent wake cycle
• Go to bed ONLY when you are (feel) tired and ready to sleep ~~ if you are in bed and not sleeping get out of bed
• Only use your bed for sleeping purposes
• Regularly exercise
• Avoid alcohol and caffeine in the evening

Question 17

Pharmacological Treatment for Insomnia

Answer 17

• Can be addictive
• Has adverse side effects
• May lead to rebound insomnia

Question 18

Narcolepsy

Answer 18

• A sleep disorder characterized by an irregular control of sleep-wake cycles

Question 19

Symptoms of Narcolepsy

Answer 19

• “Sleep attacks”
• Cataplexy
• Sleep Paralysis
• Hypnagogic (sleep onset) and Hypnopompic (sleep offset) hallucinations
• Disturbed nighttime sleep

Question 20

Causes and Treatment for Narcolepsy

Answer 20

CAUSES: Insufficient hypocretin producing neurons in the hypothalamus
TREATMENT: Stimulants and behavioural strategies

Question 21

(Obstructive) Sleep Apnea

Answer 21

Disorder caused by a blockage of the airway during sleep. Results in a daytime fatigue

Question 22

Sleep Apnea

Answer 22

Creates: Night sweats, weight gain, hearing loss, irregular heartbeat and raises the risk of death
Treatment: Weight loss, CPAP air mask

Question 23

Night Terrors

Answer 23

• A sudden waking episode which is characterized by screaming, perspiring and confusion which is followed by a return to deep sleep
• Lasts a few minutes
• Happens in stage 3&4
• Harmless
• Treatment: Get old

Question 24

Sleep Walking

Answer 24

• Somnabulism
• Walking while fully asleep
• Occurs during deep sleep phase
• Usually harmless
• Person is unaware that they have done it
• Occurs more often in children
• Perfectly fine to wake up a sleep walker

Question 25

Dreams

Answer 25

• Many people dream, but not many can recall
• 0.38% of people have been found to NEVER dream

Question 26

Dreams: Cross-Cultural Similarities

Answer 26

• Typically more negative than positive
• Ratio of make to female characters in a dream
  ~ 1:1 for women
  ~2:1 for men
• Dream content is more continuous with past or present pre-occupations of the dreamer

Question 27

Dreams - Freud

Answer 27

• Dreams reflect “wish-fulfillment” of unconscious desires
  ~ Prevents unconscious urges from ruining sleep.
• These primitive unconscious urges/desires are expressed within the dream and require “interpretation”

Question 28

Manifest Content

Answer 28

The raw facts and details about the dream

Question 29

Latent Content

Answer 29

The underlying meaning about details within the dream

Question 31

Dreams: Activation Synthesis Theory