1. Sleep, Sleep disorders, Biological rhythms
Biomedical Technology II (Honors)

2. Sleep Natural part of life REQUIRED FUNCTION
Spend about 1/3 of life asleep
REQUIRED FUNCTION

3. Sleep
Research unable to identify function of sleep, though its necessity has been repeatedly proven
Rats deprived of sleep will die within 2-3 weeks, similar timeframe to starvation
Sleep is a dynamic process
What does this mean?

4. Biology of sleep
Characteristic physiological changes in the organs of the body
How can sleep be measured?
Electroencephalogram (EEG)
Electrooculogram (EOG)
Electromyogram (EMG)

6. Biology of sleep
The use of these measures has helped us identify two basic stages of sleep: Non-rapid eye movement (NREM) and Rapid eye movement (REM)

7. NREM
4 stages based on amplitude and frequency of brain wave (EEG) activity
In general, EEG pattern of NREM is slower and more regular than when awake
As sleep gets deeper, the brain waves get slower and have greater amplitude

8. REM EEG during REM sleep shows fast and desynchronized activity
Similar to EEG from awakeness
Characterized by bursts of rapid eye movement
Eye movement is not constant, but instead consists of a darting back and forth/up and down
Movement is synchronous between eyes as when awake
Dreaming is believed to occur during this stage, however the why still remains unanswered

10. Sleep
Cyclic process; people experience repeated cycles of NREM and REM sleep, beginning with REM
Cycle lasts about min; repeated 4-6 times per night
As the night progresses, deep NREM decreases and REM increases