Ultradian rhythms Flashcards
How ma distinct stages of sleep are there and how long does each cycle last?
4 stages, each cycle lasting 90 minutes
how can the stage of sleep be investigated?
using an EEG
what is stage one?
light sleep, where a person is easily woken and hs alpha brain waves
what is stage 2?
deeper sleep, brain waves slow down and gain amplitude becoming beta waves
what is stage 3?
slow-wave sleep, difficult to wake someone, sow brain waves with large amplitudes, delta brain waves
what is REM sleep?
the body is paralysed but brain activity speeds up to resemble an awake brain, highly correlated with dreaming
on average how many sleep/wake cycles does someone have?
4/5
what is the cycle stages?
1,2,3,2,rem,1
describe Dement and Kleitman’s study
- monitor the sleep pattern on 9 adults in sleep lab using an EEG and EOG
- controlled th effect of caffeine and alcohol
- woken by bell randomly and asked if they were dreaming and if so, what about
what were Demet and Kleitman’s findings?
- Dreaming happens in REM sleep
- we have 90 min sleep cycles
what were the strengths of Dement and Kleitman’s findings?
- standardised procedure
- 61 nights of data
- replications found similar findings
what is the application of this research?
used to identify sleep disorders
