Dermet and Kleitman's study of REM sleep

• what did dermet and kleitman look to investigate?

  investigate the link between dreams and stages of sleep.
• The researchers were intrested in...?

  ...the function of REM sleep and whether eye movements during movements during REM were connected to dreaming.

  in other words - they wanted to figure out 'what is the purpose of REM sleep and why do we dream during it?'
• how many people were involved in the study?

  9 adults (7 male, 2 female)
• what were they told to avoid for the study?

  they were told to avoid caffeine and alcohol during the day.
• where did they sleep?

  the participants slept in the sleep labratory and were woken up several times by the researchers during the night.
• what were they asked?

  they were asked if they had been dreaming, and if so, what their dreams had been about and how long it had lasted.
• An EEG was used to record the signals of electrodes which were attached to the participates face and scalp.

  5 main participants spent between 6-17 nights in the lab.

  Approximately 50-77 times awakenings.
• Findings (dreaming) - what did they establish?

  established that dreams can be measured objectively.
• Dermet and Kleitman found that participants were much more likely to say if they had been dreaming if woken during REM sleep, doing so on almost 80% of wakings, compared to around 9% if woken during nREM sleep.

  They also said their dream had been shorter if woken up 5 minutes after the start of REM phase, compared to being woken 15 minutes after it started. (dreaming)
• Eye movement did appear to be linked to what participants were dreaming about. A participant who had been making left to right movement of the eyes reported a dream about people throwing tomatoes at each other. Another participant making up and down eye movements reported dreaming about a ladder.
• Evaluation - strengths

  +a lab experiment with cafefully controlled variables (number of participants, length of time dreaming).

  +evidence that dreams can be researched objectively (i.e. using a scientific method!).
• Evaluation - weaknesses (1)

  +the study lacks ecological validity. The situation in which the participants had to sleep was unusual and could have affected their sleep patterns.

  +the nature of the method of waking participants may have affected their ability to recall their dreams.

  +participant effect may have been the problem i.e. wanting to please the researchers. They may have made up a dream/lied about caffeine consumption etc.
• Evaluation - weaknesses

  +A further problem with the study was the small sample size which included only 2 females, potentially biasing the results towards the dream patterns of men rather than women.
• Evaluation - weaknesses

  +Subsequent studies have not supported Dermet and Kleitman's findings that there is a relationship between eye movements and what the person is dreaming about, as evidenced by people blind from birth showing signs of REM.
• Evaluation - weaknesses

  +Some subsequent studies have found that there are large differences between individuals in their reports of dreaming during REM.