Dement and Kleitman (1957) Dreaming and REM Study

A set of Question-and-Answer flashcards covering the Dement and Kleitman (1957) dream study, including aims, methods, key findings, dream-content associations, and evaluation.

What were the three aims of Dement and Kleitman's 1957 study on eye movements and dream activity?

1) To test whether more dreaming occurs during REM sleep than non-REM sleep; 2) To test whether there is a positive correlation between the objective length of REM sleep and the subjective duration of reported dreaming; 3) To examine whether the pattern of rapid eye movements relates to the content of the dream.

How many participants were involved and what was their gender distribution?

9 participants: 7 males and 2 females.

What monitoring equipment was used to record sleep in the study?

Polysomnography (PSG) with EEG and EOG, plus electrodes to record muscle tension, heart rate, respiration, and brain activity.

How were dreams reported to minimize bias?

Dream reports were recorded into a device rather than spoken directly to researchers.

How were participants awakened during the study?

Participants were awakened during REM or non-REM sleep (deliberately or randomly), and some were awakened 5 or 15 minutes after REM began to judge dream duration.

How was the length of a dream measured?

By the number of words in the dream narrative, then correlated with the duration of REM sleep prior to awakening.

What were the four eye movement patterns used to trigger awakenings?

Mainly vertical, mainly horizontal, both vertical and horizontal, and very little or no eye movement.

What was found about the frequency of dreaming in REM versus non-REM sleep?

More dreams were reported in REM sleep than in non-REM sleep.

When dreams were recalled from non-REM sleep, when did they most often occur relative to REM?

Most often close to the end of REM periods.

What correlation was found between dream narrative length and REM duration?

A significant positive correlation: longer dream narratives were associated with longer REM sleep.

What was the relationship between REM eye-movement patterns and dream content?

There was a very strong association between patterns of eye movements and the content of dream reports.

What dream content was associated with vertical REM periods?

Dreams of looking up and down at cliff faces, ladders, and basketball nets.

What dream content was associated with mainly horizontal REM periods?

A dream of two people throwing tomatoes at each other.

What dream content was associated with vertical and horizontal REM periods?

Dreams of looking at close objects.

What dream content was associated with very little or no REM periods?

Dreams of looking at distant objects.

What was a major limitation regarding generalisability of the study?

Small sample size with more men; results cannot generalise to women or children.

What issue related to ecological validity did the study have?

lab-based with low ecological validity; field studies could increase ecological validity.

What ethical issue did waking participants raise according to the evaluation?

Waking people from sleep is considered unethical by the British Psychological Society (BPS).

What positive contribution did the study provide regarding dreaming research?

Provided evidence that dreams can be studied objectively and opened avenues for researching how environmental stimuli affect dreaming.

How was control over extraneous variables described in the study?

High control in a laboratory setting; participants avoided caffeine and alcohol to ensure these didn’t affect the dependent variable.