The Relation of Eye Movements During Sleep to Dream Activity

JOURNAL OF EXPERIMENTAL PSYCHOLOGY, VOL. 53, NO. 5, 1957

AUTHOR DETAILS

  • William Dement ¹ and Nathaniel Kleitman ²

  • Affiliation: Department of Physiology, University of Chicago

INTRODUCTION

  • The study focuses on the relationship between dream activity and physiological variables during sleep.

  • Purpose: Establish a reliable method to determine the occurrence of dreaming by correlating it with measurable physiological phenomena.

  • Key findings from Aserinsky and Kleitman:

    • High incidence of dream recall during periods of rapid eye movements (REM) and low recall during other sleep periods.

    • Confirmed in various subjects, including both normal and schizophrenic individuals.

    • These REM periods appeared regularly throughout sleep cycles as indicated by EEG readings.

OBJECTIVES OF THE STUDY

  1. Elicit Dream Recall: Test if dream recall correlates with rapid eye movements.

  2. Duration Comparison: Examine the relationship between the subjective duration estimates of dreams and actual REM durations.

  3. Pattern Analysis: Investigate if eye movement patterns correspond to dream content (visual experiences vs. random motor discharges).

METHOD

PARTICIPANTS

  • Nine subjects: Five studied intensively and four minimally to confirm initial results.

  • Gender breakdown: Five adult males and two adult females.

PROCEDURES

  • Subjects arrived at the laboratory before bedtime, instructed to avoid alcohol and caffeine.

  • Electrodes attached to:

    • Near the eyes, to measure corneoretinal potentials during eye movements.

    • Scalp, to record brain wave patterns (EEG) for depth of sleep.

  • Experiment conducted in a dark room with minimal distractions; all electrical equipment was designed to prevent entanglement.

  • Continuous recording of EEG patterns during sleep.

DATA COLLECTION

  • Multiple awakenings throughout the night to test dream recall.

  • Summary of experiment data (Table 1 includes number of nights, average nightly awakenings, and sleeping times).

    • E.g., Subject DN averaged 8.3 nights and 7.50 awakenings per night.

RESULTS

OCCURRENCE OF EYE MOVEMENTS

  • All subjects exhibited rapid eye movements (REM) during sleep.

  • EEG patterns during REM showed low-voltage, fast wave activity; NREM periods showed high-voltage slow wave patterns.

  • No REM observed at the onset of sleep, but a pattern similar to those occurring in REM appeared later in the night.

  • Mean duration of REM periods: ranged from 3 to 50 minutes, averaging around 20 minutes, increasing as the night progressed.

FREQUENCY OF REM PERIODS

  • Regular intervals noted among individuals.

    • E.g., Subject DM averaged 70 minutes between REM periods.

  • Group average: One REM period every 92 minutes.

  • The impact of awakenings on REM was minimal regarding the onset timing of subsequent REM periods post-awakening.

DREAM RECALL ASSOCIATION

  • Awakenings were conducted using a standardized stimulus, an audible doorbell.

  • Subjects reported whether they dreamt and described dreams if they could.

  • Table 2 summarizes instances of dream recall following REM and NREM awakenings.

    • High recall recorded during REM awakenings compared to very low recall during NREM awakenings.

IMPACT OF AWAKENING TIMING

  • Notably, the recall incidence dropped drastically following NREM awakenings post-REM (e.g., Only 5 out of 17 recalled dreams after NREM, within 8 minutes of a REM period ended).

  • Subjects exhibited a better recall from REM period awakenings, especially when NREM awakenings were performed at sleep stages that showed greater likelihood for dreams.

SUBJECTIVE DREAM DURATION ESTIMATES

  • Initially, subjects found estimating dream duration too challenging.

    • Later tests included awakening after fixed 5 or 15 minutes of REM to improve accuracy in recalls.

  • Recall duration estimates showed subjects' ability to choose correct durations with notable precision, aside from deviations by DN.

EYE MOVEMENTS AND DREAM CONTENT

  • Hypothesis: Eye movements reflect visual imagery of dreams; attempted to match eye movement patterns with dream content.

  • Four predominant eye movement patterns were examined:

    1. Vertical movements

    2. Horizontal movements

    3. Both types of movements

    4. No movement at all.

  • Specific example dreams were detailed for patterns related specifically to actions experienced in dreams (e.g., climbing vs. watching).

DISCUSSION

  • Findings affirm that REM periods correlate with conscious dreaming activity.

  • Noted that relinquishing reliance solely on subjective recall enhances the objectivity of dream studies.

  • Critical to note irregularities and variations in individual sleep patterns, which underscore unique dreaming experiences.

  • Emphasized the potential to investigate the impact of envirnoments and psychological states on dreams through REM monitoring.

SUMMARY

  • High incidence of dream recall correlated with REM phases measured during continuous sleep across subjects.

  • Subjective timing of dream durations aligns closely with actual REM durations, emphasizing the connection between dream activity and physiological indicators.

  • Variations in eye movement patterns suggest a connection between visual engagement in dreams and underlying REM activity.

REFERENCES

  1. Aserinsky, E., & Kleitman, N. Two types of ocular motility occurring in sleep. J. appl. Physiol., 1955, 8, 1–10.

  2. Blake, H., Gerard, R., & Kleitman, N. Factors influencing brain potentials during sleep. J. Neurophysiol., 1939, 2, 48-60.

  3. Davis, H., et al. Human brain potentials during the onset of sleep. J. Neurophysiol., 1938, 1, 24-38.

  4. Dement, W. Dream recall and eye movements during sleep in schizophrenics and normals. Journal of Neurology, 1955, 122, 263-269.

  5. Dement, W., & Kleitman, N. Incidence of eye motility during sleep in relation to varying EEG patterns. Fed. Proc., 1955, 14, 216.