Dement and Kleitman

State how Dement and Kleitman chose whether to wake a participant after 5 minutes or after 15 minutes of REM sleep. [1]

State how Dement and Kleitman chose whether to wake a participant after 5 minutes or after 15 minutes of REM sleep. [1]

at random

Outline one conclusion from Dement and Kleitman about the relationship between eye movements and dreaming. [2]

-Eye movements appear to correspond to dream content
-Eye movements occur in "real time" in dreams, not at random

Outline one quantitative result from the 'dream-duration estimates' in Dement. You must use data in your answer. [2 marks]

-On 88% of trials (45/51) the participants estimated 5 mins correctly
-On 78% of trials (47/60) the participants estimated 15 mins correctly
-Ps were more accurate at predicting after 5 minutes compared to 15 minutes.

Outline one qualitative result from the dream content reports in Dement study. [2]

-One P reported a dream of standing at the bottom of a cliff (1 mark) and looking at climbers (2 marks)
-One P reported a dream of standing at the bottom of a cliff (1 mark) operating a hoist (2 marks)
-One P reported climbing up a ladder (1 mark) and looking up and down as he climbed (2 marks)
-One P reported watching two people throw tomatoes at each other (2 marks)
-One P reported shooting a basketball then looking down to get the next one (2 marks)

Describe the dream-duration estimates for the participant DN whose responses did not follow the same pattern as others. [2]

1 mark per:
-DN was equally likely to get the 15 minute estimation right or wrong
-He got estimation of 15 minutes correct 50% of the time/5 times
-He got estimation of 5 minutes correct 80% of the time/8 times
-He often underestimated how long the dream lasted

Outline one strength of the Dement and Kleitman study. [2]

-Procedures were standardised, including a doorbell sound which woke up all participants immediately and prevented Ps from forgetting their dreams, increasing the reliability.
-Participants were told not to drink coffee or alcohol to avoid extraneous variables and increased internal validity.
-Conducted in a laboratory, which allowed researchers greater control over extraneous variables, increasing internal validity.

Participants were woken at two different time intervals during REM sleep and asked to estimate their dream-duration. One of the time intervals was five minutes. State the other time interval. [1]

15 minutes

Name the apparatus used to measure brain activity in this study. [1 mark]

Electroencephalogram

Outline one dream reported by a participant that had horizontal eye movements. [2]

-Watching two people throwing tomatoes at each other
-Driving a car and at an intersection a car sped from left
-Driving a car and looking ahead then a man appeared on left/stood on pavement

Outline what is meant by the ethical guideline of 'valid consent'. [2]

-This is when a participant is given enough information before a study begins (informed)
-so they can decide whether they would like to participate or not (consent)
-They should not be coerced or compelled to participate

Outline why Steve is correct that this study (Dement) is ethical, using evidence in your answer. [4]

-Confidentiality was maintained in this study (1 mark outline);
-The results only used initials to identify participants (1 mark evidence)
-They were not deceived as they knew that their sleep/dreams were getting monitored (1 mark evidence);
-The participants were not forced to tell their dream narratives so it can be argued that privacy was given (1 mark evidence)
-EEGs do not pose any risk to people so physical protection was adhered to in the study (1 mark)

Outline the debate about individual and situational explanations in psychology, using an example from the study by Dement and Kleitman. [4]

Individual

Define: We behave a certain way because of our personality

Ex: Participants had different success at estimating dream duration

Situational

Define: We behave a certain way because of environmental influence

Ex: Sleeping in a laboratory may have caused Ps to have strange dreams

Explain what psychologists have learned about sleep and dreams using two results from the study by Dement and Kleitman. Do not refer to the debate about the individual and situational explanations in your answer.

-People tend to dream more in REM sleep than they do in NREM sleep.
-Ps woken from REM reported dreams 80% of the time, compared to only 7% in nREM.
-Direction of eye movement in REM relates to dream content so it is not random.
-Vertical movement was linked to playing basketball whilst horizontal movement was linked to throwing tomatoes.

Suggest two real-world applications based on the study by Dement and Kleitman (sleep and dreams). [4]

It can help people with sleep related disorders (1 mark: what). Patients can be attached to an EEG monitor to see if brain waves whilst sleeping are typical or not (1 mark: how).

It can be used in therapy involving dream analysis (1 mark: what). Patients can be woken up in REM sleep (via a device that detects REM sleep) and asked to recall the content of their dream immediately (1 mark: how).

It can be used to promote better quality sleep (1 mark: what). People can use their watch / sleep app to measure/track sleep/REM time to see if sleep is good or needs 'improving' (1 mark: how).

Describe the psychology that is being investigated in the study by Dement and Kleitman. [5]

-Rapid Eye Movement / REM sleep is a phase of sleep where a person is paralysed
-REM/nREM cycles and sleep stages are part of people's ultradian rhythms
-Their eyes flicker and they can breathe but all other muscles are paralysed
-Non Rapid Eye Movement / nREM sleep are the other stages of sleep and they differ in brain activity
-Dreaming is a subjective experience of imagery while we are asleep
-Electroencephalograms (EEGs) measure brain wave activity
-They are used to measure the amplitude and frequency of brain waves.

Describe the procedure of the Dement and Kleitman from when the participant arrived at the laboratory until the participant fell asleep for the first time. [4]

-They were instructed to eat normally but abstain from alcohol and coffee.
-EEG electrodes were attached to the participants' head to measure brain waves and near their eyes to measure eye movements.
-They electrode wires were gathered into a "ponytail" to make sleeping easier.
-Participants went to sleep in a dark, quiet room.

Outline how dream recall was recorded during the Dement and Kleitman study. [2]

-Participants were awoken by a loud doorbell and asked if they had been dreaming.
-They were asked speak into a recording device (located near the bed) and a narrative of what happened in the dream.
-Sometimes researchers would enter the room to ask follow-up questions about their dreams.

Outline all three aims of the Dement and Kleitman study.

-To investigate if eye movement patterns were related to dream content
-To investigate if there is a difference in dream recall between REM and nREM sleep
-To investigate if there was a (positive) correlation between estimates of dream duration and length of REM sleep

In the study by Dement and Kleitman (sleep and dreams), the procedure that the researchers first used to measure participants' estimations of REM sleep duration was unsuccessful and had to be revised.
(a) Describe how the researchers first attempted to measure participants' estimations of REM sleep duration. [2]
(b) Describe the revised procedure used to measure participants' estimations of REM sleep duration. [2]

(a) Participants were woken at different increments and asked to estimate how long they had been dreaming, rather than being given a fixed choice.
(b) Researchers began waking participants up after 5 or 15 minutes of REM sleep and giving them a fixed choice.

Name two things that participants were asked to do (or not to do) prior to the Dement and Kleitman study. [2]

Do:
-arrive a little before their normal bedtime
-eat normally
Don't:
-drink alcohol
-drink caffeine

Outline one quantitative result from the Dement and Kleitman study.
[2]

-Participants were more likely to recall a dream in REM (1 mark) compared to nREM sleep (1 mark)
-On 88% of trials the participants were accurate at estimating 5 minutes dream duration (1 mark) compared to 78% of trials for 15 minutes (1 mark)
-Participants were more likely to correctly identify 5 minutes of REM (1 mark) compared to 15 minutes of REM (1 mark)

In which stage of sleep did participants recall most of their dreams? [1]

REM

An EEG (electroencephalogram) was used in this study. What does an EEG measure? [1]

Brain waves or brain activity

Evaluate the study by Dement and Kleitman (sleep and dreams) in terms of two strengths.

Strengths

-The quantitative data gathered by the EEG and the standardised procedure for all Ps increased the reliability of the results.

-Because the experiment was conducted in a laboratory, researchers were able to use advanced tools (like the EEG) and maintain a high level of control over variables (like the waking process). This also leads to a high degree of internal validity.

-The study makes use of clear and definitive quantitative data to prove its first aim - that dream recall was much higher in REM compared to NREM sleep. The researchers were also able to gain immediate qualitative data through interviewing the participants about their dreams.

Explain why the relationship between REM duration and dream narrative was a correlation, not an experiment. [4]

To be an experiment, a researcher must manipulate one of the variables. In this case, REM periods were allowed to continue naturally, then compared to the length of the dream narrative participants produced.

How was the variable of dreaming operationalised in the Dement and Kleitman study? [1 mark]

A recollection that included content, not just an impression of dreaming.

Evaluate the generalisability of the Dement and Kleitman study. [2]

-The inclusion of both genders increases the generalisability,
-but the small sample size (9 total, 5 active) limits it.

Describe one result about dream recall from REM awakenings in the first half of the night compared to the second half of the night. [2]

There were more dreams recalled in the second half compared to the first half for the entire sample

Describe what is meant by REM sleep. [4]

It is Rapid Eye Movement sleep
Our body is paralysed
More likely to recall dreams
Increases in length every (sleep) cycle;
Brain activity/waves most similar to when awake
Occurs at regular intervals during the night
Usually every 90 minutes
Average length 20 minutes;
It is the last stage of the sleep cycle

Evaluate the study by Dement and Kleitman (sleep and dreams) in terms of two weaknesses.

-Generalisability: The sample size was small (only 5 studied in depth), so the results may not be generalisable to the larger public.

-Ecological validity: Sleeping in a laboratory was likely quite unnatural, and Ps were asked to abstain from alcohol or caffeine before bed. This reduced the mundane realism of the task and may have caused Ps to sleep/dream differently than they normally would. This may reduce the ecological validity of the results.

-Ethics: One participant (WD) was deceived by the researchers, who told him he would only be woken from REM sleep. If Ps sleep was disturbed or lower in quality, it may cause physical harm. Ps may have felt pressured to reveal dreams that they would have preferred to keep private, as they reported them immediately upon waking.

Participants arrived at the laboratory before their usual bedtime. Outline the procedure from AFTER a participant arrived at the laboratory until the end of the study. [4]

(Two or more) electrodes were attached near to the eyes of the participant.
(Two/three) electrodes were attached to the scalp.
They went to bed in a quiet/dark room.
All electrode lead wires were attached to top of head. This was in a single cord/ponytail.
The EEG ran continuously all night.
At various times during the night the participants were woken by a bell
And asked to recall dreams / estimate time in REM.

Outline one conclusion from this study in relation to eye movement during REM sleep. [2]

Eye movements during REM tend to fit with what the dreamer is looking at suggesting eye movements are not 'random' at all.