Articles
Slow-Wave Sleep and Waking Cognitive Performance Among Older Adults With and Without Insomnia Complaints

https://doi.org/10.1016/S0031-9384(98)00316-3Get rights and content

Abstract

Previous research has shown that healthy young adults with relatively fast reaction times on daytime testing have significantly more nocturnal slow-wave sleep than do age-matched subjects with relatively slow reaction times on such testing. The current study was conducted to examine the relationship between slow-wave sleep and cognitive performance among older adults with and without insomnia complaints. A sample of 32 noncomplaining older (age ⩾ 60 years) normal sleepers and a like-aged sample of 32 insomniacs, recruited to participate in a larger study, served as subjects. All subjects underwent nocturnal sleep monitoring immediately prior to undergoing a battery of daytime tests that measured simple reaction time, vigilance/signal detection, and complex reaction time. Results from the normal sleepers showed no relationship between daytime cognitive performance measures and a variety of computer-derived nocturnal slow-wave sleep measures. In contrast, insomniac subjects with relatively slow reaction times showed relative deficits in a spectral analytically derived measure of slow-wave power in the 2 to 4 Hz bandwidth. These results suggest that relative performance deficits among some older insomniacs may be related to specific slow-wave sleep deficiencies. However, among older normal sleepers, intersubject differences in performance appear unrelated to slow-wave sleep measures. Additional research is needed to further explore the possible restorative role slow-wave sleep may serve for cognitive functions other than those examined herein.

Section snippets

Subjects

Data gathered for the current investigation were obtained from a cohort of older adults while they participated in a larger study designed to test the effects of home and lab sleep monitoring on a variety of nocturnal and diurnal measures. Participants included 32 (16 women, 16 men) older (Mage = 67.5 years; SD = 5.7 years) normal sleepers and 32 (16 women, 16 men) older (Mage = 67.7 years; SD = 4.8 years) insomniacs who were recruited through announcements posted within two medical centers

Descriptive Data

Table 1 shows means and standard deviations of visually scored and computer-scored sleep data for our two subject groups as well as similar descriptive statistics for their performance tests results. These data show that the normal sleepers, on average, had slighlty more consolidated and deeper sleep than did the insomnia sufferers, but there was considerable overlap between these two groups in regard to their sleep measures. Similarly, the performance data suggested considerable overlap

Discussion

Various studies have found that sleep deprivation is associated with a decrement in waking cognitive performance [e.g., 6, 7, 11, 21, 22, 35]. Furthermore, results obtained by Jurado et al. (24) have suggested that cognitive performance decrements may be associated specifically with a relative deficit of slow-wave sleep among healthy young normal sleepers. The purpose of the present study was to examine whether a similar relationship between cognitive performance and slow-wave sleep might also

Acknowledgements

This research was supported by the Department of Veterans Affairs Merit Review Program.

References (36)

  • M.H. Bonnet

    Effect of sleep disruption on sleep, performance, and mood

    Sleep

    (1985)
  • M.H. Bonnet

    Performance and sleepiness as a function of frequency and placement of sleep disruption

    Psychophysiology

    (1986)
  • D.E. Bunnell et al.

    Effects of exhaustive exercise on the sleep of men and women

    Psychophysiology

    (1983)
  • M.J. Chambers et al.

    The role of state-trait anxiety in insomnia and daytime restedness

    Behav. Med.

    (1993)
  • R. Downey et al.

    Performance during frequent sleep disruption

    Sleep

    (1987)
  • J.D. Edinger et al.

    Sleep in the laboratory and sleep at homeComparisons of older insomniacs and normal sleepers

    Sleep

    (1997)
  • J.D. Edinger et al.

    Aerobic fitness, acute exercise and sleep in older men

    Sleep

    (1993)
  • I. Feinberg et al.

    Flurazepam effects on slow-wave sleepStage 4 suppressed but number of delta waves constant

    Science

    (1977)
  • Cited by (88)

    • Sleep and Cognition in Older Adults

      2018, Sleep Medicine Clinics
    View all citing articles on Scopus
    View full text