Stage 1
Stage one lasts:
five minutes
What percentage of sleep time does stage 2 take up?
around 45% to 50% (more than any other stage)
What state is stage 4 similar to?
A coma or brain death, you don't dream or feel pain in this stage
What does REM stand for?
Rapid eye movement
As we fall asleep our mind stays _____
Active
The initial transformation happens _____
Quickly
What indicates that stage 2 has begun?
electric bursts called spindles
Are delta waves present more in stage 4 or stage 3?
stage 4, they are present for more than half the time
REM lasts:
5-20 minutes, doubling each cycle
New what are consolidated while we sleep?
What does EEG stand for?
Electroencephalogram
What can the strength of nightly spindles predict?
general intelligence
How long does your body stay in stage 4?
Only 30 minutes
What mental state do some sleep scientists believe a person is at during REM?
How perky (cheerful) we're feeling at any moment depends on the interaction of what two processes?
"Sleep pressure" and our "circadian rhythm"
Stage one is also called the ______ end of sleep
shallow
What is a key benefit that we get from this stage?
The brain makes connections we won't when awake and overall memory can be better after a night of sleep because of connections made in stage 2
What happens if one doesn't get stage 3 and 4 sleep?
stage 3 is when growth hormones are produced the most, they are needed all throughout life, if stage 3 is not achieved these hormones will not be produced
stage 4 is when the body repairs and regrows tissues, builds bone and muscle, and strengthens the immune system, you are in a much weaker state and will show symptoms of being sleep deprived after missing even one night of deep sleep (both stage 3 and 4)
What cellular process peaks during REM?
Protein synthesis.
Sleep is essential for maintaining what three necessities for your body?
immune system, body temperature, and blood pressure.