Dement and Kleitman (2)
M&P: The nine participants were seven adult males and two adult females. Five were studied intensively, while only a small amount of data was collected on the other four just to back up the findings of the main five. The participants were studied under controlled laboratory conditions, whereby they reported to the laboratory just before their usual bedtime. They had been asked to eat normally but to avoid caffeine or alcohol on the day of the study. The participants went to bed in a quiet, dark room. An electroencephalograph (EEG) was used to amplify and record the signals of electrodes which were attached to the participants face and scalp. Two or more electrodes were attached near to the participants’ eyes to record electrical changes caused by eye movement. Two or three further electrodes were attached to the scalp to record brain activity which indicated the participants’ depth of sleep.
Testing Hypothesis 1: (there will be a significant association between REM sleep and dreaming): At various times during the night (both during REM and N-REM sleep) the participants were awakened to test their dream recall. The participants were woken up by a loud doorbell ringing close to their bed. The participant then had to speak into a tape recorder near the bed. They were instructed to first state whether or not they had been dreaming and then, if they could, to report the content of the dream.