Sleep

Question 1

Why do we need sleep? (5)

Answer 1

• Maintenance of brain and restoration of tissues
• Ontogenetic development of brain
• Key learning/memory processes
• Energetically favourable (sensory systems aren’t useful in dark)
• Dreaming

Question 2

What sleep stage and frequency is associated w/
- Light sleep
- NREM2
- Deep/Slow wave sleep
- Dream stage

Answer 2

Light:
- NREM1, low frequency alpha and theta waves

NREM2:
- Low frequency theta w/ sleep spindles and k-complexes

Deep:
- NREM 3/4, low frequency delta and some spindles

Dream:
- High freq beta waves (like awake), atonia (no movement)

Question 3

Sleep disturbances common in what % of older adults
What sleep stages decrease w/ age (2) + other changes in sleep (3)

Answer 3

50%
- NREM3 and REM decreases
- Greater sleep latency, more arousal periods, less overall sleep

Question 4

Insomnia
- Acute vs chronic time period
- Primary vs Secondary/comorbid

Answer 4

Difficulty falling asleep or staying asleep
- Can be acute or chronic (>3-6 months) and may have recurring bouts
- Primary rare (10% of cases); secondary common (90% of cases), tends to be comorbid w/ depression and anxiety

Question 5

Subjective vs objective analysis of sleep
- Subjective’s benefits (4) and cons (2)
- Objective’s techniques (2) and major variables (3)

Answer 5

Subjective: Survey patients about sleep patterns using questionnaires; usually done first and tells doctor what to look for
- Athens insomnia scale (looks at type of problem and severity to figure out treatment), Pittsburgh sleep quality index, insomnia severity index, sleep diaries
- Cheap/quick/accessible, first and necessary step in addressing sleep problem, all studies include subjective analysis, info about attitudes and beliefs can help identify other problems
- Doesn’t address physio function and relies on honest/accurate reports by patient

Objective: Observing neurological and physio activity during sleep; expensive and not done unless necessary/know what to look for already
- Polysomnography (includes EEG, EMG, EOG, breathing monitors, etc); Actigraphy (measures sleep-wake times on wrist and verifies sleep diary)
- Sleep onset latency (time taken to fall asleep), time spent awake/number of awakenings, total sleep time/time in each stage

Question 6

Treating sleep disorders:
- Sleep hygiene
- Pharmacotherapy
- Cognitive-behavioural treatment interventions (CBT-I)

Answer 6

Sleep hygiene:
- First step in treating sleep problem, educates ppl on good sleep practices
- Correlated w/ fewer sleep problems in University

Pharmacotherapy:
- Benzodiazepines most often used short-term, but non-benzodiazepines (lunesta, ambien, sonata) getting more popular bcuz less toxic despite being less effective
- Melatonin also useful for hormone regulating sleep-wake cycles

CBT-I:
- Get patient to change cognitive relationship with sleeping and adopt new sleep-related cognitions
- Ideal for long-term

Question 7

MBSR vs drugs effect on
- Sleep onset latency
- Awakenings after sleep onset
- Sleep efficiency

Answer 7

MBSR reduces latency and awakenings and increases efficiency
- Similar to drugs but weaker effects

Question 8

Drugs vs CBT effect on sleep latency and efficiency
MBSR vs MBTI vs simple self monitoring effect on total wake time, pre-sleep arousal and ISI score
Studies’ results on CBT effect length and relapse

Answer 8

CBT showed pronged changes in latency and efficiency and no tolerance effects
—
MBTI had lower wake time, arousal, and ISU score
- MBSR still better than normal self-monitoring but better to be paired w/ CBT
—
Effects last up to 10+ years after termination of treatment
Better reaction to relapses than hypnotic drugs (benzodiazepines)

Question 9

Mindfulness has greatest effect on what aspect of sleep + smaller effect on what
Meta-analysis shows that mindfulness is better that ___ but not ___

Answer 9

Perceived sleep quality
Total wake time
—
Better than active controls (relaxation)
But not evidence-based treatments (drugs)

Question 10

Why may meditation be useful in treating insomnia?

Answer 10

Reduces hyperarousal, which is activation of sympathetic nervous system and HPA axis (cortisol)
- Cortisol increase assoc w/ waking respinse
- Meditation can lower stress and rebalance cortisol lvls, change cognition (reduce pre-sleep worries, negative cognitions), encourage acceptance (thus reducing rumination)

Question 11

Controversy of meditation and sleep studies (3)
- Britton et al. study

Why might meditation disrupt sleep? (2)

Answer 11

• Field now in universal agreement about how it effects sleep
• Old studies show weak effects (starting to become more positive opinions recently)
• Britton study shows long term meditation is associated with less time in deep sleep, more time in light sleep, and higher arousal levels despite increased self reported sleep quality and improved mood
  
  • Possibly shows decreased sleep need instead
    —
    1) May disrupt default mode network
• Affected by meditation but involved in sympathetic arousal and sleep
  2) Britton’s study used sample in remission from depression (population may be producing diff results than healthy pop)