Dement + Kleitman

• Investigated the ultradian rhythm
• Used an EEG machine
• Allowed researchers to determine 4 major phases or stages of sleep
• The 4 stages had distinct EEG readings and lowered bodily functions such as heart rate, muscle tension and body temperature
• Person becomes increasingly harder to wake at each stage of sleep cycle
• REM lasts 10-15 minutes
• Paradoxical sleep is when the person is most deeply asleep but the EEG readings are very similar to the person being awake
• Dement + Kleitman Procedure

  • lab experiment
  • participants reported to the lab just before their normal bedtime
  • asked to not consume alcohol or coffee during the day
  • electrodes attached near the eyes
  • at various times in the night a bell rang and had to state if they were dreaming
• Dement and Kleitman Sample

  • 7 males
  • 2 females
  • 5 studied intensively