Week 3 Lecture - Insomnia and mental health Flashcards
features of actigraph - what are they and what do they measure?
- Gives sleep outcomes
- Wearable device
- Measures things like duration of sleep, sleep onset latency etc
optimal sleep duration
7-9hours
normal sleep onset latency
15mins
features of the attogram/photometry - what do the different colours mean
- Black lines are movement (proprietary algorithm)
- Blue is sleep period
- Yellow is Light sensory so light intensity (essential in sleep regulation - can assist us in sleeping or inhibit sleeping, indicates whether we are asleep during a certain period)
- Green is the period of uncertainty (trying to measure sleep onset latency)
what is polysomnography (PSG) and what does it record?
- Electrodes on head/face (usually)
- Records electrical activity of brain
o Converted and interpreted
features of polyomnograph
amplitude and frequency to stage sleep
- The more asleep you are, the higher the amplitude and lower frequency
stages of sleep
N1 = drowsy
N2 = light sleep
N3 = deep sleep
R = REM sleep
how many sleep cycles per night
4-5
what is light sleep good for?
memory consolidation
what is deep sleep good for?
deep repair mode, growth hormone released in this period
what is REM sleep?
dream stage, closest to being awake, lots of brain areas active
when does most deep sleep occur?
during first part of night (before 2am)
when does most REM sleep occur?
towards end of sleep
how does the polysomnogram score sleep?
in 30s blocks
what happens to eyes during REM sleep
eyes move and roll during sleep
process behind REM sleep
Physiological process that paralyzes the body from neck down to stop us re-enacting dreams (EMG electrodes on body therefore have no activity)
how do we measure depth of sleep
auditory arousal threshold
auditory arousal threshold
the minimum amount of noise required to arouse someone from a given stage of sleep
stages of sleep and noise
- Deeper stages require more noise (and more energy)
o Important for fire alarms etc
what does a hypnogram show?
sleep cycles
what can anxiety do to sleep onset latency
may cause it to be longer
what can depression do to sleep cycle?
may cause people to wake up in middle of night and not go back to sleep
how many processes control sleep?
3
3 processes controlling sleep
- Homeostatic processes (physiological balance)
- Circadian processes (biological clock)
- Psychological processes (learning, cognitive arousal, automaticity)
what homeostatic process controls sleep?
sleep homeostasis: sleep pressure