1. What is sleep? Flashcards
(40 cards)
Sleep is defined as a n____ recurring, r____ state of p____ disengagement, reduced c____ and relative i____
A naturally recurring, reversible state of perceptual disengagement, reduced consciousness and relative immobility.
The propensity of sleep is pattered by h____ and c____ factors
Homeostatic and circadian factors
Sleep is a non-____ biological state required for the ____ of life - our need for sleep parallels those for ____, ____ and ____
negotiable
maintenance
air
food
water
What are some things that sleep impacts?
1. M____, c____ and l____
2. Aspects of our e____ and how we r____ them
3. W____ clearance from the b____
4. N____ metabolism
5. I____ responses
- memory, cognition, learning
- Emotions, regulate
- Waste, brain
- Nutrient
- Immune
What is fatal familial insomnia?
A rare inherited disease that results in severe insomnia and eventually death
How long does each sleep cycle last?
Around 90 minutes
How many sleep cycles do you typically have over the course of a sleep period?
5-6 sleep cycles
What are the two broad sleep stages?
- NREM
- N1
- N2
- N3/4 - REM
- Rapid Eye Movement
When is her proportion of NREM and REM typically higher?
NREM higher at start of sleep period
REM higher towards end of sleep period
Sleep architecture is often graphically represented in a what?
Hypnogram
Where do the following attach?
1. Electroencephalogram (EEG)
2. Electromyogram (EMG)
3. Electro-oculogram (EOG)
- records electrical brain potentials from the scalp
- electrodes attached to chin to monitor muscles activity
- attached around eyes to monitor eye movements
What is on the x axis in PSG data?
Time is across x-axis
each mini square = 1 second
What is meant by frequency?
How many cycles of a waveform you see every second
What activity happens when someone is awake and attentive?
Beta activity (13-30Hz)
What activity happens when eyes are closed and starting to get drowsy?
Alpha activity (8-12Hz) - associated with state of relaxation
What do we see in N1 (transition to sleep)
Slow rolling eye ,movements
Looks like drowsiness but start to see more theta waves (4-8Hz)
What are three subtypes of hypnogogic hallucinations in stage N1?
Tetris effect
Auditory
Falling sensation
When does N2 happen?
After about 10 mins
What are K-complex delta waves in N2?
Special kind of delta wave
Sudden sharp waveforms unique to N2
Represent inhibitory mechanism to prevent awakening
How much of sleep does N2 make up?
Around 50% of total sleep
What are the two things characteristic of stage N2?
Sleep spindles
K-complexes
What other name is N3 known as?
Slow-wave sleep
What is N3 characterised by?
low frequency, high amplitude EEG activity known as delta waves
When will your body prioritise N3?
After you have been sleep deprived to compensate for the loss