Dement and Kleitman (Sleep and Dreams) AICE Psychology Review

Aim

determine the relationship between eye movements and dreams.

Hypothesis 1

There will be a significant association between REM and dreaming

Hypothesis 2

There will be a significant positive correlation between the duration of dreams and duration of eye movement.

Hypothesis 3

There will be a significant relationship between eye movement patterns and dream content

Sleep Drive

A major drive aroused by the physiological requirements for sleep.

Alpha Rhythm

A state in which brain waves show a dominant frequency of about 9 to 13 waves per second, usually when the person is relaxed, with eyes closed.

Sleep Stages

The changes in the brain waves indicating light to deep sleep

Myoclonic jerk

a sudden spasm in body caused by a tiny burst of brain activity

Rapid Eye Movement (REM)

Stage of sleep in which our eyes move rapidly under the lids, which is associated with vivid, visual dreams. (20% of sleep is REM)

Non-Rapid Eye Movement (nREM)

Stage of sleep (1-4) in which our eyes are still. It is also called quiescent (quite) sleep. This is not associated with dreaming.

REM is also known as…..

paradoxical sleep

Stages of sleep: Awake/Relaxed

Alpha Waves

Stage I

pulse slows, relax, breathing uneven, waves irregular, drifting * Beta waves = small irregular waves

Stage II

Eyes roll (10min. Later) / strange images and thoughts/ / *sleep spindles= fast, irregular / k complexes= large and slow (alpha waves)

STG III

(30 minutes later) muscles relax, blood pressure decreases, breathing becomes even- harder to wake *Theta waves = deeper sleep

STG IV

•Delta Sleep/ Dreamless oblivion/ stay here about 20 min. at a time before you drift upward towards a lighter sleep. * Delta waves = slow, regular waves

Electroencephalograph (EEG)

Machine used to detect and record electrical activity in nerve and muscle cells when many are active at the same time. It uses macroelectrodes, which are large electrodes stuck to the skin or scalp

Frequency

Number of events per fixed period of time, e.g. the number of eye movements per minute (approximately 60/minute in REM sleep) or the number of brain waves (cycles) per second or Hertz (Hz), e.g. 13-30 Hz for beta waves.

Amplitude

"Height" of waves, e.g. on an EEG (including voltage).

Internal Validity

How well an experiment controls for confounding variables.

If an experiment has internal validity,

the researcher is confident that it is only the IV that is affecting

the DV and no confounding variables are having an impact on the results.

Main ways of measuring sleep

1) EEG- Measures gross brain wave activity (large scale)

Electric (electro)….in head (encephala)……writing (gram)

2)EMG- Measures electrical activity of muscles

3)EOG- Measures eye movement

electroculargraph

Location

Lab experiment(dark room)

Extraneous Variables:

Consumption of caffeine or alcohol (tried to control for), consumption of foods/beverages that impact dream content, experiences that may impact sleep patterns, noises outside that would disrupt sleep (extraneous noise-situational variable), comfort level (mundane realism)

Equipment:

EEG (the means of collecting data and verifying the results)

Population

•Seven adult males, 2 adult females (5 studied intensively, 4 had data gathered minimally with the main intent of confirming the results on the first 5.)

Experimental Design

•Repeated measure (Repeated measures design is a research design that involves multiple measures of the same variable taken on the same or matched subjects either under different conditions or over two or more time periods. )

Procedure

Gave informed consent

Subjects report to lab before bed time

2 electrodes attached to eyes in order to test muscle activity

2-3 to skull to test brain activity, put into bed.

Hypothesis 1 Procedure

awoken with doorbell during various stages of REM and NREM sleep in order to record dreams into recorder. First stated if they were dreaming and second was the content (those incoherent (mumbling or incomplete sentences) was not considered to be a remembered dream.

Schedule for Hypothesis 1

•2 awoken at random, 1 awoken 3 times in REM and 3 in NREM and continued pattern, 1 awoken randomly but told he would only be awoken during REM (told to counterbalance to alleviate demand characteristics), 1 on a whim.

Hypothesis 1 IV

Rapid eye movements

Hypothesis 1 DV

whether or not dreaming

Results for H1

Results show that REM sleep is associated with dreaming, and NREM sleep is associated with periods of non-dreaming sleep .

H2 IV

5 or 15 mins of eye movement

H2 DV

DV= how long the person thinks they are dreaming.

H2 Procedure

•Participants are woken up 5 or 15 minutes into REM

•Participants were asked how long they thought the dream was (5 or 15 minutes - structured question)

Results for H2

•Results revealed that all but one of the participants were able to choose the correct dream duration fairly accurately

•Participant (DN) could only recall latter part of the dream and so underestimated its length. He consistently underestimated dream duration, often choosing 5 min instead of 15. (refer to Table 2)

•Using REM periods over a range of durations, narratives from 152 dreams were collected. However, 26 of these could not be used as they were too poorly recorded for accurate transcription.

•Even though this was affected by how expressive the participant was, a significant positive correlation was found to be ranging from .4 to .71 for each participant

•Findings show that we dream relatively in real time

H3 IV

pattern of eye movement

H3 DV

Actual Dream content

H3 Procedure

•Participants were awoken as soon as 1 of 4 patterns persisted for at least a minute:

•(a)vertical eye movements

•

• (b) horizontal eye movements

•

• (c) both vertical and horizontal eye movements

•

• (d) no movement

•

•Describe the dream content

H3 Results

•Results: Periods of pure vertical or horizontal patterns were rare.

•35 awakenings from the 9 subjects Only one instance of pure horizontal (dream content was people throwing tomatoes) movement was recorded and three instances of pure vertical (dream content was climbing a ladder, throwing basketballs at a net, standing at the bottom of a cliff & looking up)

•On 10 occasions subjects were awakened after a period of little/no eye movement

•Definite relationship between dream content and eye movement

•In the 21 awakenings after a mixture of movements, subjects were always looking at things close to them (people & things) (No recall of distant or vertical activity)

Reductionism

•Reductionism- the practice of analyzing and describing a complex phenomenon in terms of a simpler reason.

General Results

•REM occurred to each participant each night.

•Low voltage of EEG -- accompanied REM

•High voltage of EEG -- in between REM cycles.(nREM)

•Negative correlation (opposite relationship) between voltage and movement patterns (eye activity)

•REM never occurred at the beginning of a sleep cycle.

•

•AVERAGE SLEEP TIME WAS: 6 hours (and 3 minutes)

•Range 4h20m-7h50m

•

•Dream recall during non-REM can be assumed because the memory of the dream persisted for an unusually long time.

•REM periods that were not terminated by awakening varied 3 - 50 minutes, ( average of 20 minutes)

• Duration of non-termination lasted longer as night continued

•Intervals = regular … patterns= unique

•Mean period time phase between entire group - 92 min. (90 minute cycle generally)

Conclusions

•DREAMS are more likely to occur during REM sleep

Eco Validity

•low due to lab environment and electrodes utilized. Furthermore, the extent of a participant's dependence on coffee/alcohol may affect sleeping patterns or dreams.

Extraneous/confounding variables

•prohibition of caffeine and alcohol may have changed comfort and patterns of sleep as well as dreams

Researcher/experimenter variable

•occasionally entered room to further question subjects, could cause anxiety in subjects or other emotional factors/responses….could affect further sleep patterns or dreams

Situational Variable

environment/lab may have caused change in sleep patterns

Demand characteristics

•Demand characteristics were generally alleviated by participants recording responses - could have been when researcher entered for questioning

Ethical Considerations

•Artificial setting may have inhibited restful sleep.

•Lack of 100% transparency.

•Subject WD was mislead (deception)/ can't give informed consent

•Restricted something they may normally consume. (Alcohol and caffeine)

•Having them strapped to electrodes may have caused discomfort.

•Could cause residual trauma or evoke previous emotional distress.

•(Being watched while sleeping in a strange room)

Short and Long-term implications

•Could potentially assist in learning more about how abnormal sleep patterns and dreams affect a person physically, mentally and emotionally during a day/life

•-could allow us to understand the importance of sleep and sleep/dream patterns (i.e the implications of abnormal sleep patterns)

Generalizability

Only 5 people were studied "in detail" and four more used to confirm the findings.

Could make it difficult to generalize beyond the sample of people because of the sample size is small.