Dement & Kleitman

What were the THREE hypotheses?

• there will be a significant association between REM sleep & dreaming

• there will be a significant positive correlation between the estimate of duration of dreams and the length of eye movement

• there will be a significant association between the pattern of the eye movent & context of dream

Describe the sample used in the study:

7 males and 2 females

5 were intensely studied (the other 4 were used as data confirmation)

What was the experimental design used?

They used a laboratory experiment as well as observation.

ONE limitation of this sample:

It is ethnocentric as they were all american participants.

However, in the physiological approach a small sample is not important as the assumption is that we are biologically the same.

ONE strength of this sample:

As it is a small sample you are able to study them more in depth, increasing the reliability of the results.

Outline the procedure.

• Subjects reported to the lab before bed time
• They had been asked to abstain from caffeine and alcohol but had been advised to eat normally.
• 2 electrodes were placed near the eyes
• There were another 3 placed around the head to measure brain activity
• Woken by a bell at various times in the night to assess dream recall
• They recorded their own dream with a hand held tape recorder

The waking times were as follows:

2 were woken at random, 1 was woken 3x in REM sleep and 3x in Non-REM sleep, 1 woken at the whim of the experimenter and 1 was woken at random but told that it was during REM.

What was the macheine called that measured brain waves?

EOG- Electroculogram

What was the macheine called that measured eye movement?

EEG- Electroencephalogram

Outline the results.

• Significantly more dreams were reported in REM sleep than Non-REM sleep
• When dreams had failed to be recalled it was usually early on in the night
• When subjects reporrted dreams from Non-REM sleep it was within 8 minutes of a REM sleep period
• There is an average gap of 90 minutes between REM cycles
• Duration of REM is 3-50 minutes

TWO strengths and TWO weaknesses

Strenghts:

• They had high control eg. location, sleeping time, woken by a bell. Which means that there is high reliability found in the precise measurements of REM and non REM by EEG readings. They also showed objectivity.
• It was useful in the sense that it helps us to understand sleep and dreams and disorders such as night terrors, giveing us a strategy of perhaps waking them before they reach REM sleep.

Weaknesses:

• It is reductionist, dreaming is reduced to just brain activity and eye movement
• There was low ecological validity; slept in the lab, woken from sleep by a bell, having to record dreams etc.

What did the eye movements mean?

Vertical Movements> up and down movements in a dream such as operating a hoist.

Horizontal Movements> sideways movements in a dream such as watching tennis.

Both> talking to people that you are close to eg. Family and friends

Very little/No movement> staring at fixed objects