Unit 9: Sleep and Dreaming Flashcards
How many cycles are in a typical night of sleep?
5 cycles
How long does each cycle last in your sleep?
90 minutes
What is REM sleep?
rapid eye movements
part of the sleep cycle with rapid eye movements caused by eyes moving a lot behind the eyelids when dreaming occurs.
Describe stage 1 of the sleep cycle
light sleep
- can be easily woken up
- muscles less active
- eye movements slow
- sudden twitching
- alpha and theta brainwaves
Describe stage 2 of the sleep cycle
late night stage
- brainwaves slower
- mainly theta waves
- eye movements stop
- bursts of brain activity (spindles)
- temperature and heart rate drop
Describe stage 3 of the sleep cycle
deep sleep
- slow delta brainwaves
- some faster waves
- between light and deep sleep
this is when nightmares and sleep walking occur
Describe stage 4 of the sleep cycle
deep sleep
- almost all slow delta waves
- hard to wake you up
- no eye movements
- woken very disoriented
What are some features that occur during REM sleep?
flickering eyelids, irregular breathing, muscle paralysis, heart rate + blood pressure rise
Describe the stages of the sleep cycle
first you go through stages 1-4, this is known as the NREM sleep
after that you have REM sleep which is where you dream
How many hours on average do people dream per night?
2 hours
What is sensory blockade?
when in REM sleep all incoming sensory information is blocked
What is movement inhibition?
when in REM sleep movement is prevented as muscles are paralysed, The pons send a signal to the spinal chord to shut off neurons which prevents us from moving.
How many hours of sleep do adults need?
7-8 hours
How many hours of sleep do teenagers need?
9 hours
What is sleep deprivation?
not having enough sleep, which can affect physical functioning and brain functioning
