Special Environments

• The sleep stages are REM & non-REM sleep. they are determined by EEG, EOG & EMG activity. In 90 minute cycles, stages 1-4 NREM sleep & REM sleep occur.
• In wakefulness, EEG activity is low amplitude high frequency. In sleep, EEG activity is high amplitude low frequency.
• Tiredness is determined by the circadian rhythm, super chiasmatic nucleus and sleep promoting factors E.g. adenosine which quietens the reticular formation to promote sleep