Dement and Kleitman Flashcards
What are the main assumptions of the biological approach?
- Behaviours, cognitions and emotions can be explained in terms of the working of the brain and the effect of hormones, genetics and evolution.
What was the psychology investigated in Dement and Kleitman’s study?
- The association between dreams and the stages of sleep.
- To see whether dreams occurred during REM or nREM.
State the aims of the study of Dement and Kleitman’s study. (4)
1- To see if dream recall occurs during REM or non-REM sleep.
2- To see if there is a link between the estimate of dream length and length of REM period.
3- To see if the pattern of eye movements is related to dream content.
4- To see if there is a positive correlation between the length of REM and the number of words given in a dream narrative.
State the apparatus used in Dement and Kleitman’s study.
- EEG –> electrodes attached to the scalp to detect and record electrical activity in never and muscle cells to measure brain waves, frequency and amplitude.
- EMG –> used to detect and measure muscle movements.
- EOG –> electrodes placed around the eyes to detect eye movements during sleep.
State the research method used in Dement and Kleitman’s study.
Laboratory experiment in a sleep lab at the university of Chicago.
State the experimental design in Dement and Kleitman’s study.
Repeated measures design.
State the variables of aim 1 in Dement and Kleitman’s study.
IV : Whether woken up in REM or nREM.
DV : Whether participant could recall dream or not.
State the variables of aim 2 in Dement and Kleitman’s study.
IV : Whether woken up 5 or 15 minutes after the onset of REM.
DV : Perception of whether they had been dreaming for 5 or 15 minutes.
State the variables of aim 3 in Dement and Kleitman’s study.
IV : Eye movement pattern before waking
- mainly vertical
- mainly horizontal
- both vertical and horizontal movements
- little to no movements
DV : description of the dream
State the variables of aim 4 in Dement and Kleitman’s study.
Co-variable 1: The numbers of minutes spent in REM sleep
Co-variable 2: The number of words in the corresponding dream narrative recording.
State the controls of Dement and Kleitman’s study.
- Eat normally but no caffeine or alcohol.
- Arrive at normal bedtime.
- Slept in dark, quiet room with EEG electrodes attached to scalp in a ponytail to allow head movements.
- Woken up by a doorbell.
What was the sampling technique used for Dement and Kleitman’s study?
Volunteer sampling.
State the sample of Dement and Kleitman’s study.
- 7 males and 2 females
- 5 studied in detail and 4 were used to confirm results.
State the procedure for aim 1 in Dement and Kleitman’s study. (3)
- Participants were either woken up during REM or nREM sleep but weren’t told which.
- The participant stated whether or not they were having a dream and if they were then dream content was described into a recorder.
- Occasionally the experimenter would enter the room when participant finished to ask further questions.
State the procedure for aims 2&4 in Dement and Kleitman’s study. (3)
- Participants were woken up after either 5 or 15 minutes of REM sleep.
- Participant guessed which duration they had been dreaming for.
- Number of words in dream narrative was counted.
State the procedure for aim 3 in Dement and Kleitman’s study. (2)
- Direction of eye movement was detected using EEG electrodes around the eye.
- Participants were woken after a single eye movement pattern lasted for more than one minute and asked to report their dream.
State the overall findings of Dement and Kleitman’s study. (4)
- Dement and Kleitman found that REM sleep never occurred immediately after the onset of sleep but occurred at regular intervals during the night.
- Frequency of REM periods was constant for each participant but length varied between them.
- Duration of REM ranged from 3-50 minutes.
- REM periods were longer later into the night.
Results for aim 1 in Dement and Kleitman’s study. (2)
- Dream recall occurred mainly in REM sleep.
- Participants had a high incidence dream recall following REM awakening.
Results for aim 2 in Dement and Kleitman’s study. (4)
- All participants had been able to determine whether they were dreaming for 5 or 15 minutes. (83%)
- One participant was only able to guess correctly 63% of the time, tended to underestimate his dream lengths.
- 88% of participants guessed the 5 minutes correctly.
- 78% of participants guessed the 15 minutes correctly.
Results for aim 3 in Dement and Kleitman’s study.
- Eye movement patterns were related to dream content.
Describe dreams with vertical eye movement. (3)
- Involved climbing up a series of ladders and looking down as he climbed.
- Shooting a basketball at net.
- Standing at the bottom go a tall cliff operating a lifting machine (hoist) and looking up at climbers at various levels.
Describe dreams with horizontal eye movement.
Two people throwing tomatoes at each other.
Describe dreams with no eye movement.
Staring at a distant object.
Describe dreams with mixed eye movements.
Looking at close objects or people, or fighting with someone.
State the results for aim 4 in Dement and Kleitman’s study.
Moderate positive correlation between duration of REM and number of words in dream narrative.
State the conclusions of Dement and Kleitman’s study. (4)
- Dreaming occurred during periods of REM sleep in distinct episodes through the night.
- Dream recall is likely to happen because dreams are being recalled from the previous REM phase.
- Measurement of eye movements and brain waves has shown that dreams progress in real time.
- Eye movements are not purely random but are related to dream content.
