Sleep Brain

Question 1

Process S vs process c

Answer 1

S= sleep homeostasis
C= circadian system

Question 2

Sleep plasticity

Answer 2

We fill sleep debt with sleep intensity (more stage2 and 3) not necessarily more hours

Question 3

sleep architecture of N1,2,3

Answer 3

wake
REM - eye movement, low muscles tone, theta to beta, memory and learning
Stage 1 - eyes roll, alpha to theta
Stage 2 - sleep spindles
Stage 3 +4 - delta, recovery, growth

Question 4

REM is

Answer 4

Rapid eye movement

Question 5

depth of sleep increases when deprived

what chemical?

Answer 5

adenosine to cells
builds up across wakefulness, decreaes during sleep
- adenosine receptors increase somnolence (sleepiness)

Question 6

Circadian system

melatonin

Answer 6

suprechaismatic nucleus - master body clock in the anterior hypothalamus
- melanopsin photo receptors sensitive to blue light
- melatonin = hormone promotes sleep

Question 7

Melatonin

Answer 7

• low when awake, back up post-lunch dip
• sunlight decreases melatonin
• alertness aligns with body core temperature

Question 8

when body temp cools:

Answer 8

• sleepiness
• bigger distance between process S and C = urge to sleep

Question 9

Process S and C in lifespan

Answer 9

• change as you develop
• Wake up asleep Onset (time awake) increases as you age
• sleep latency = time taken to fall asleep
• slight decrease in amount of sleep
• less deep sleep as you age

delayed sleep pushes cycle and melatonin

Question 10

measuring sleep

Answer 10

• polysomnography
• using EEG, eye movement, muscle tone
• EKG heart rate,

these can be expensive, first night effect machinery
not for insomnia

Question 11

Measuring circadian rhythm

Answer 11

• melatonin:
• salivary dim light melatonin onset
• plasma - blood sample
• urinary collection

core body temp rhythm:
- rectal temp
- ingetible pills

Question 12

Measure sleep with

Answer 12

• actigraphy (objective) - wristband, records weeks
• sleep diary + questionnaires (subjective) biases tho
• wearables - widely available

Question 13

Sleep disorders:

Answer 13

• insomnia
• delayed sleep-wake phase disorder
• narcolepsy, cataplexy

Question 14

Insomnia

Answer 14

• 10% common
  = difficulty sleeping + maintaining
• at least 1 symptom (fatigue, irritable, reduced energy, sleep concern)
• unhelpful - laying awake, too long in bed
• treatment with CBT, sleep restriction therapy

Question 15

Insomnia
Spielman’s model
(3 Ps)

Answer 15

• predisposing - gender, age, genetic
• precipitating - event eg job, stress
• perpetuating - thoughts, beliefs

Question 16

Delayed sleep-wake phase disorder is

Answer 16

• delay 2+ hour of sleep desired/required
• difficulty falling asleep, clock time
• slower circadian oscillator
• TREATMENT - light therapy

Question 17

Narcoplexy =

cataplexy

Answer 17

sleep attack - 5/30mins
- entering REM sleep
- cataplexy = loss of muscle tone
- DUE TO orexin/hypocretin - neuropeptide in hypothalamus
- patients have slow degeneration of them

treat with amphetamines, nodafinil

Question 18

REM sleep behaviour disorder

Answer 18

• behaviour and noises during sleep
• DUE TO neurodegenetation of brainstem, prevents paralysis during REM
• treat with anti-axiolytics, but sedated

Question 19

Inadequate sleep affects…

Answer 19

• physical heath
• psychosocial
• risky behaviour
• school

Question 20

Fatal familial insomnia

Answer 20

• inability to sleep developed after midlife
• PRNP gene defect - protein accumulates in brain
• 1-2 million ppl