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. 2020 May:132:109992.
doi: 10.1016/j.jpsychores.2020.109992. Epub 2020 Mar 4.

Manipulating sleep duration perception changes cognitive performance - An exploratory analysis

Shadab A Rahman  1 , Dharmishta Rood  2 , Natalie Trent  2 , Jo Solet  3 , Ellen J Langer  2 , Steven W Lockley  4
Affiliations

Manipulating sleep duration perception changes cognitive performance - An exploratory analysis

Shadab A Rahman et al. J Psychosom Res. 2020 May.

Abstract

Objectives: To test the effect of perceived sleep duration on cognitive performance.

Methods: Sixteen healthy individuals [8F; mean age (± SD): 24.2 ± 3.0 years)] received an 8-h sleep opportunity followed by a 5-h opportunity on two consecutive nights. Upon waking, they were randomized to being informed that they received either an 8-h or 5-h sleep opportunity, via a clock that ran either fast, slow or normally. Cognitive performance was assessed using 10-min auditory psychomotor vigilance tests and subjective sleepiness ratings. Homeostatic and circadian sleep drive was assessed using waking electroencephalography (EEG).

Results: Reaction time was significantly quicker when individuals thought that they had slept for 8 h but given a 5-h sleep opportunity. Conversely, reaction times were significantly slower when individuals thought they had 5 h of sleep but given an 8-h sleep opportunity. EEG delta power (1.0-4.5 Hz) during wake increased significantly when sleep was restricted to 5 h, and individuals thought they slept for 5 h, but this increase was attenuated with a perceived sleep duration of 8 h following a 5-h opportunity. EEG delta power did not increase, however, with perceived sleep restriction. EEG high-alpha activity (10.5-11.5 Hz) was consistently higher when participants thought that they had an 8-h sleep opportunity, regardless of the actual duration.

Conclusions: These results suggest that perceived sleep duration may modulate psychosomatic responses. Additional studies with predefined outcomes and analyses are necessary to confirm these findings, which may have important implications for understanding how sleep affects cognition and psychosomatic responses.

Keywords: Alertness; Cognition; False-clock paradigm; Perceived time; Sleep.

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Conflict of interest statement

Declaration of Competing Interest None of the authors report financial interests associated with the work presented. Holds patents for prevention of circadian rhythm disruption by using optical filters and improving sleep performance in subjects exposed to light at night. SAR owns equity in Melcort Inc. SAR has provided paid consulting services to Sultan & Knight Limited, Bambu Vault LLC. SAR has received honoraria as an invited speaker and travel funds from Starry Skies Lake Superior, University of Minnesota Medical School, PennWell Corp., Seoul Semiconductor Co. LTD. In the last 3 years, SWL reports commercial interests from the last 3 years (2015–2018), unrelated to the work, that are listed below. Dr. Lockley has received consulting fees from the Atlanta Falcons, Atlanta Hawks, Delos Living LLC, Noble Insights, OpTerra Energy Services Inc., Pegasus Capital Advisors LP, Serrado Capital, Slingshot Insights and Team C Racing. He has current consulting contracts with Akili Interactive, Apex 2100 Ltd., BHP Billiton, Consumer Sleep Solutions, Headwaters Inc., Hintsa Performance AG, Light Cognitive, Lighting Science Group Corporation, Mental Workout, McCullough Hill Leary PS, Paul, Weiss, Rifkind, Wharton & Garrison LLP, PlanLED, Six Senses, Stantec and Wyle Integrated Science and Engineering. Dr. Lockley has received unrestricted equipment gifts from Biological Illuminations LLC, Bionetics Corporation and F.LUX Software LLC; has equity in iSLEEP, Pty; royalties from Oxford University Press; honoraria plus travel, accommodation and/or meals for invited seminars, conference presentations or teaching from BHP Billiton, Estee Lauder, Informa Exhibitions (USGBC), and Teague; travel, accommodation and/or meals only (no honoraria) for invited seminars, conference presentations or teaching from IES, Lightfair, USGBC, DIN and SLTBR. Dr. Lockley has completed investigator-initiated research grants from Biological Illumination LLC and has an ongoing investigator-initiated grant from F. Lux Software LLC; He is a Program Leader for the non-profit CRC for Alertness, Safety and Productivity, Australia, through an adjunct faculty position at Monash University and unpaid Member of the Scientific Advisory Board for the non-profit Midwest Lighting Institute. Dr. Lockley holds a process patent for ‘Systems and methods for determining and/or controlling sleep quality’, which is assigned to the Brigham and Women's Hospital per Hospital policy. Dr. Lockley has also served as a paid expert in legal proceedings related to light and health.

Figures

Fig. 1.
Fig. 1.. Study protocol.
All individuals completed a 6-hour light exposure prior to sleep on Day 1 as part of an unrelated study. All participants slept 8 hours on Night 1 and 5 hours on Night 2. The randomization of what they were informed resulted in two study groups: (1) Night 1 – slept 8 hours, duration informed (DI) 8 hours; Night 2 – slept 5 hours, DI 8 hours (n=8; Fig 1A); (2) Night 1 – slept 8 hours, DI 5 hours; Night 2 – slept 5 hours, DI 5 hours (n=8; Fig 1B). Cognitive batteries were completed hourly during the day after the 8-hour sleep opportunity (on ▼DI = 8 h group; ▲ DI=5 h group) or after the 5-hour sleep opportunity (on ᐁDI = 8 h group;Δ DI=5 h group). Symbols are maintained across all plots. (D/C = Discharge).
Fig. 2.
Fig. 2.. Effects of perceived sleep duration on neurobehavioral outcome measures.
Time course (mean±SEM) of neurobehavioral variables after an 8-hour sleep opportunity (left panels) and duration informed (DI) 8 h (▼) or 5 h (▲) and after a 5-hour sleep opportunity (right panels) and duration informed 8 h (ᐁ) and 5 h (Δ). Study protocol plotted in the first row illustrates the timing of the measures compared in the lower panels. Neurobehavioral variables included subjective sleepiness (A and B), reaction time (C and D), attentional failures (reaction time > 500 msec) (E and F), pre-test subjective performance rating (G and H) and pre-test subjective effort rating (I and J). * Signifies main effect of group p<0.05; repeated measures REML linear regression (main and interaction effects of group x time). There was a significant effect of time (p<0.05) only on subjective sleepiness in the 8 h actual sleep opportunity condition.
Fig. 3.
Fig. 3.. Effects of perceived sleep duration on electroencephalographic markers of arousal.
Group mean (±SEM) (A, B, E and F) and time course (mean ±SEM) (C, D, G and H) of EEG markers of arousal in the 8 hour (filled gray bars and ▼) and 5 hour (filled black bars and ▲) duration informed (DI) groups under actual 8-hour sleep opportunity (left panel) or in the 8-hour (unfilled gray bars and ᐁ) and 5-hour (unfilled black bars and Δ) DI groups under actual 5-hour sleep opportunity. Arousal measures included absolute power in the delta band (1.0–4.5 Hz) (A-D) and relative power density in the high-alpha band (10.5–11.5 Hz) (E-H). * Signifies main effect of group p<0.05; repeated measures REML linear regression [with either only group (A, B, E and F) or main and interaction effects of group x time (C, D, G and H)]. There was no significant effect of time or interaction on any of the measures.
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References

    1. Langer E, Djikic M, Pirson M, Madenci A, Donohue R. Believing is seeing: using mindlessness (mindfully) to improve visual acuity. Psychol Sci. 2010; 21 (5): 661–666. - PubMed
    1. Langer EJ. Mindfulness: Addison-Wesley/Addison Wesley Longman, 1989.
    1. Langer EJ, Chanowitz B, Palmerino M, Jacobs S, Rhodes M, Thayer P. Higher stages of human development: Perspectives on adult growth. New York, NY, US: Oxford University Press, 1990.
    1. Park C, Pagnini F, Reece A, Phillips D, Langer E. Blood sugar level follows perceived time rather than actual time in people with type 2 diabetes. Proc Natl Acad Sci U S A. 2016; 113 (29): 8168–8170. - PMC - PubMed
    1. Durmer JS, Dinges DF. Neurocognitive consequences of sleep deprivation. Semin Neurol 2005; 25 (1): 117–129. - PubMed

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