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Performance, Mood, and Brain and Metabolic Functions During Different Sleep Schedules (STAVAR)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details.
 
ClinicalTrials.gov Identifier: NCT04731662
Recruitment Status : Recruiting
First Posted : February 1, 2021
Last Update Posted : May 10, 2021
Sponsor:
Information provided by (Responsible Party):
June Chi Yan Lo, National University, Singapore

Brief Summary:
This proposed project will investigate whether a variable or a stable sleep schedule will be more effective in minimizing neurobehavioural and metabolic deficits when total sleep opportunity across two weeks is below the recommended sleep duration. In this laboratory-based, stay-in study, 60 young adults will be randomized into 1 of 3 groups. After 2 nights of 8-h time-in-bed (TIB) that simulate longer sleep opportunities typical of weekends, the stable short sleep group will have a 6-h TIB in each of the following 5 'weeknights' (8866666). The variable short sleep group (8884846) will also have a total TIB of 30h during the 'weeknights', although TIB varies across the 'weeknights'. The nightly TIB of the well-rested control group will be 8h (8888888). These manipulations will repeat in the second week, enabling the tracking of outcome measures during recurrent weeks of sleep restriction on 'weekdays' and extension on 'weekends'. A test battery assessing basic cognitive functions and mood will be administered 5 times a day. A long-term memory encoding task will be administered after week 1. A functional Magnetic Resonance Imaging (fMRI) brain scan, and an Oral Glucose Tolerance Test (OGTT) will be conducted after the second 'weekend' night and after the last 'weeknight' each week. Continuous glucose monitoring will be conducted throughout the experiment. Sleep will be measured every night with polysomnography.

Condition or disease Intervention/treatment Phase
Sleep Sleep Restriction Behavioral: Short sleep Behavioral: Variable short sleep Not Applicable

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 60 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: Effects of Recurrent Short and Variable Sleep on Cognitive Performance, Brain Dynamics, Psychological Well-being, and Glucose Metabolism
Actual Study Start Date : February 1, 2021
Estimated Primary Completion Date : January 11, 2024
Estimated Study Completion Date : April 11, 2024

Arm Intervention/treatment
No Intervention: Control Group (8888888)
The Control group will have 8-hours time-in-bed, both weeknights and weekends.
Experimental: Stable Short Sleep (8866666)
The short sleep group will have 6-hours time-in-bed on weeknights and 8-hours time-in-bed on weekends.
Behavioral: Short sleep
6-hours time-in-bed during weeknights

Experimental: Variable short sleep group (8884846)
The short sleep group time in-bed will vary across weeknights but will maintain the same amount of total time-in bed as the stable short sleep (8866666).
Behavioral: Variable short sleep
Variable hours of time-in bed during weeknights




Primary Outcome Measures :
  1. Change in sustained attention assessed with the Psychomotor Vigilance Task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep restriction and recovery [ Time Frame: 5 times daily for 16 days ]
    Number of attention lapses (>500ms)

  2. Change in mean reaction time assessed with the Psychomotor Vigilance Task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep restriction and recovery [ Time Frame: 5 times daily for 16 days ]
    Mean reaction time

  3. Change in median reaction time assessed with the Psychomotor Vigilance Task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep restriction and recovery [ Time Frame: 5 times daily for 16 days ]
    Median reaction time

  4. Change in standard deviation in reaction time of sleep restriction and recovery [ Time Frame: 5 times daily for 16 days ]
    Standard deviation in reaction time

  5. Change in number of commission errors / false starts assessed with the Psychomotor Vigilance Task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep restriction and recovery [ Time Frame: 5 times daily for 16 days ]
    Number of commission errors / false starts

  6. Change in number of correct matches assessed with the 1-back task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Number of correct matches in the 1-back task

  7. Change in number of correct mismatches assessed with the1-back task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Number of correct mismatches in the 1-back task

  8. Change in number of incorrect matches assessed with the1-back task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Number of incorrect matches in the 1-back task

  9. Change in incorrect mismatches assessed with the1-back task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Number of incorrect mismatches in the 1-back task

  10. Change in discriminability measure (A') assessed with the1-back task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Discriminability measure (A')

  11. Change in bias measure (B"D) assessed with the1-back task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Bias measure (B"D)

  12. Change in number of correct matches assessed with the 3-back task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Number of correct matches in the 3-back task

  13. Change in number of correct mismatches assessed with the 3-back task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Number of correct mismatches in the 3-back task

  14. Change in number of incorrect matches assessed with the 3-back task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Number of incorrect matches in the 3-back task

  15. Change in number of incorrect mismatches assessed with the 3-back task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Number of incorrect mismatches in the 3-back task

  16. Change in discriminability measure (A') assessed with the 3-back task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Discriminability measure (A')

  17. Change in bias measure (B"D) assessed with the 3-back task from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Bias measure (B"D)

  18. Change in the level of subjective sleepiness assessed with the Karolinska Sleepiness Scale from morning to afternoon then evening from baseline days to the first and second cycle of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Score on the Karolinska Sleepiness Scale (1-9 points)

  19. Change in positive mood assessed with the Positive and Negative Affect Scale (PANAS) from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Total score on the positive subscale of the PANAS

  20. Change in negative mood assessed with the Positive and Negative Affect Scale (PANAS) from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily for 16 days ]
    Total score on the negative subscale of the PANAS

  21. Change in the level of depressive symptomatology from the mornings of the second baseline day to the last day of the first sleep manipulation cycle and the last day of the second sleep manipulation cycle. [ Time Frame: 3 separate days (Day 3, 8 and 15) ]
    Score on the Mood and Anxiety Symptom Questionnaire (Scale 1-5)

  22. Change in the level of anxiety symptomatology from the mornings of the second baseline day to the last day of the first sleep manipulation cycle and the last day of the second sleep manipulation cycle. [ Time Frame: 3 separate days (Day 3, 8 and 15) ]
    Score on the Mood and Anxiety Symptom Questionnaire (Scale 1-5)

  23. Change in the level of satisfaction with life from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily (09:00, 12:00, 15:00, 18:00, 21:00) for 16 days ]
    Score on the Satisfaction with Life Scale (1-7 scale)

  24. Change in speed of processing assessed with the Mental Arithmetic Test (MAT) from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily (09:00, 12:00, 15:00, 18:00, 21:00) for 16 days ]
    Number of correct response in the task

  25. Change in speed of processing assessed with the Symbol Digit Modalities Test from morning to afternoon and then evening from baseline days to the first and second cycles of sleep manipulation and recovery [ Time Frame: 5 times daily (09:00, 12:00, 15:00, 18:00, 21:00) for 16 days ]
    Number of correct responses in the task

  26. Changes in the blood glucose levels from morning of the second baseline day to the last day of the first sleep manipulation cycle and the last day of the second sleep manipulation cycle. [ Time Frame: 3 days (Day 3, 8 and 15) 6mL blood sample collection at 15, 30, 60, and 120 minutes ]
    Area under the curve for plasma glucose

  27. Changes in the insulin levels from morning of the second baseline day to the last day of the first sleep manipulation cycle and the last day of the second sleep manipulation cycle. [ Time Frame: 3 days (Day 3, 8 and 15) 6mL blood sample collection at 15, 30, 60, and 120 minutes ]
    Area under the curve for insulin

  28. Changes in interstitial fluid glucose levels from morning to afternoon then evening from baseline days to the first and second cycles of sleep manipulation and recovery. [ Time Frame: All 16-days with 8-hour interval readings ]
    Area under the curve for interstitial fluid glucose

  29. Changes in the task related brain functional connectivity from the second baseline day to the last day of the first sleep manipulation cycle and the last day of the second sleep manipulation cycle. [ Time Frame: 3 days (Day 3, 8, 15) ]
    Brain functional connectivity in fMRI analysis

  30. Changes in the resting-state brain functional connectivity from the second baseline day to the last day of the first sleep manipulation cycle and the last day of the second sleep manipulation cycle. [ Time Frame: 3 days (Day 3, 8, 15) ]
    Brain functional connectivity in fMRI analysis

  31. Effect of variable sleep on picture encoding response time [ Time Frame: Single session (Day 8) ]
    Mean response time

  32. Effect of variable sleep on picture encoding response accuracy [ Time Frame: Single session (Day 8) ]
    Response accuracy

  33. Effect of variable sleep on picture recognition response time [ Time Frame: Single session (Day 10) ]
    Mean response time

  34. Effect of variable sleep on picture recognition hit rate [ Time Frame: Single session (Day 10) ]
    Hit rate

  35. Effect of variable sleep on picture recognition false alarm rate [ Time Frame: Single session (Day 10) ]
    False alarm rate

  36. Effect of variable sleep on picture recognition discriminability measure (A') [ Time Frame: Single session (Day 10) ]
    Discriminability measure (A')


Secondary Outcome Measures :
  1. Change in total sleep duration at night assessed with polysomnography from baseline nights to the first and second cycles of sleep manipulation and recovery [ Time Frame: Nocturnal sleep on nights 1 & 2 (baseline), 3, 4, 5, 6 & 7 (first sleep manipulation period), 8 & 9 (first recovery period), 10,11,12, 13, 14 (second sleep manipulation period), & 15 (second recovery period) ]
    Total duration of nocturnal sleep will be determined to establish baseline sleep characteristics (first and second night) and changes in the first sleep manipulation period (third, fourth, fifth, sixth and seventh sleep) the first recovery period (eight and ninth night), the second sleep manipulation period (tenth, eleventh, twelfth, thirteenth, fourteenth), and the second recovery period (15th night)

  2. Change in wake after sleep onset duration at night assessed with polysomnography from baseline nights to the first and second cycles of sleep manipulation and recovery [ Time Frame: Nocturnal sleep on nights 1 & 2 (baseline), 3, 4, 5, 6 & 7 (first sleep manipulation period), 8 & 9 (first recovery period), 10,11,12, 13, 14 (second sleep manipulation period), & 15 (second recovery period) ]
    Total duration of wake after sleep onset will be determined to establish baseline sleep characteristics (first and second night) and changes in the first sleep manipulation period (third, fourth, fifth, sixth and seventh sleep) the first recovery period (eight and ninth night), the second sleep manipulation period (tenth, eleventh, twelfth, thirteenth, fourteenth), and the second recovery period (15th night)

  3. Change sleep efficiency at night assessed with polysomnography from baseline nights to the first and second cycles of sleep manipulation and recovery [ Time Frame: Nocturnal sleep on nights 1 & 2 (baseline), 3, 4, 5, 6 & 7 (first sleep manipulation period), 8 & 9 (first recovery period), 10,11,12, 13, 14 (second sleep manipulation period), & 15 (second recovery period) ]
    Total sleep efficiency will be determined to establish baseline sleep characteristics (first and second night) and changes in the first sleep manipulation period (third, fourth, fifth, sixth and seventh sleep) the first recovery period (eight and ninth night), the second sleep manipulation period (tenth, eleventh, twelfth, thirteenth, fourteenth), and the second recovery period (15th night)

  4. Change slow wave activity/ slow wave energy at night assessed with polysomnography from baseline nights to the first and second cycles of sleep manipulation and recovery [ Time Frame: Nocturnal sleep on nights 1 & 2 (baseline), 3, 4, 5, 6 & 7 (first sleep manipulation period), 8 & 9 (first recovery period), 10,11,12, 13, 14 (second sleep manipulation period), & 15 (second recovery period) ]
    Total slow wave activity/ slow wave energy will be determined to establish baseline sleep characteristics (first and second night) and changes in the first sleep manipulation period (third, fourth, fifth, sixth and seventh sleep) the first recovery period (eight and ninth night), the second sleep manipulation period (tenth, eleventh, twelfth, thirteenth, fourteenth), and the second recovery period (15th night)

  5. Change spindle activity at night assessed with polysomnography from baseline nights to the first and second cycles of sleep manipulation and recovery [ Time Frame: Nocturnal sleep on nights 1 & 2 (baseline), 3, 4, 5, 6 & 7 (first sleep manipulation period), 8 & 9 (first recovery period), 10,11,12, 13, 14 (second sleep manipulation period), & 15 (second recovery period) ]
    Total spindle activity will be determined to establish baseline sleep characteristics (first and second night) and changes in the first sleep manipulation period (third, fourth, fifth, sixth and seventh sleep) the first recovery period (eight and ninth night), the second sleep manipulation period (tenth, eleventh, twelfth, thirteenth, fourteenth), and the second recovery period (15th night)

  6. Change in N1 sleep duration at night assessed with polysomnography from baseline nights to the first and second cycles of sleep manipulation and recovery [ Time Frame: Nocturnal sleep on nights 1 & 2 (baseline), 3, 4, 5, 6 & 7 (first sleep manipulation period), 8 & 9 (first recovery period), 10,11,12, 13, 14 (second sleep manipulation period), & 15 (second recovery period) ]
    Total duration of nocturnal N1 sleep duration will be determined to establish baseline sleep characteristics (first and second night) and changes in the first sleep manipulation period (third, fourth, fifth, sixth and seventh sleep) the first recovery period (eight and ninth night), the second sleep manipulation period (tenth, eleventh, twelfth, thirteenth, fourteenth), and the second recovery period (15th night)

  7. Change in N1 sleep percentage at night assessed with polysomnography from baseline nights to the first and second cycles of sleep manipulation and recovery [ Time Frame: Nocturnal sleep on nights 1 & 2 (baseline), 3, 4, 5, 6 & 7 (first sleep manipulation period), 8 & 9 (first recovery period), 10,11,12, 13, 14 (second sleep manipulation period), & 15 (second recovery period) ]
    Percentage of nocturnal N1 sleep duration will be determined to establish baseline sleep characteristics (first and second night) and changes in the first sleep manipulation period (third, fourth, fifth, sixth and seventh sleep) the first recovery period (eight and ninth night), the second sleep manipulation period (tenth, eleventh, twelfth, thirteenth, fourteenth), and the second recovery period (15th night)

  8. Change in N2 sleep duration at night assessed with polysomnography from baseline nights to the first and second cycles of sleep manipulation and recovery [ Time Frame: Nocturnal sleep on nights 1 & 2 (baseline), 3, 4, 5, 6 & 7 (first sleep manipulation period), 8 & 9 (first recovery period), 10,11,12, 13, 14 (second sleep manipulation period), & 15 (second recovery period) ]
    Duration of nocturnal N2 sleep will be determined to established baseline sleep characteristics (first and second night) and changes in the first sleep manipulation period (third, fourth, fifth, sixth and seventh sleep) the first recovery period (eight and ninth night), the second sleep manipulation period (tenth, eleventh, twelfth, thirteenth, fourteenth), and the second recovery period (15th night)(first and second nights) and changes in the first sleep manipulation (third, forth, fifth, sixth

  9. Change in N2 sleep percentage at night assessed with polysomnography from baseline nights to the first and second cycles of sleep manipulation and recovery [ Time Frame: Nocturnal sleep on nights 1 & 2 (baseline), 3, 4, 5, 6 & 7 (first sleep manipulation period), 8 & 9 (first recovery period), 10,11,12, 13, 14 (second sleep manipulation period), & 15 (second recovery period) ]
    Percentage of nocturnal N2 sleep will be determined to established baseline sleep characteristics (first and second night) and changes in the first sleep manipulation period (third, fourth, fifth, sixth and seventh sleep) the first recovery period (eight and ninth night), the second sleep manipulation period (tenth, eleventh, twelfth, thirteenth, fourteenth), and the second recovery period (15th night)(first and second nights) and changes in the first sleep manipulation (third, forth, fifth, sixth

  10. Change in N2 sleep latency at night assessed with polysomnography from baseline nights to the first and second cycles of sleep manipulation and recovery [ Time Frame: Nocturnal sleep on nights 1 & 2 (baseline), 3, 4, 5, 6 & 7 (first sleep manipulation period), 8 & 9 (first recovery period), 10,11,12, 13, 14 (second sleep manipulation period), & 15 (second recovery period) ]
    Duration of nocturnal N2 sleep latency will be determined to established baseline sleep characteristics (first and second night) and changes in the first sleep manipulation period (third, fourth, fifth, sixth and seventh sleep) the first recovery period (eight and ninth night), the second sleep manipulation period (tenth, eleventh, twelfth, thirteenth, fourteenth), and the second recovery period (15th night)(first and second nights) and changes in the first sleep manipulation (third, forth, fifth, sixth

  11. Change in N3 sleep duration at night assessed with polysomnography from baseline nights to the first and second cycles of sleep manipulation and recovery [ Time Frame: Nocturnal sleep on nights 1 & 2 (baseline), 3, 4, 5, 6 & 7 (first sleep manipulation period), 8 & 9 (first recovery period), 10,11,12, 13, 14 (second sleep manipulation period), & 15 (second recovery period) ]
    Total duration of nocturnal N3 sleep will be determined to establish baseline sleep characteristics (first and second night) and changes in the first sleep manipulation period (third, fourth, fifth, sixth, and seventh sleep) the first recovery period (eight and ninth night), the second sleep manipulation period (tenth, eleventh, twelfth, thirteenth, fourteenth), and the second recovery period (15th night)

  12. Change in N3 sleep percentage at night assessed with polysomnography from baseline nights to the first and second cycles of sleep manipulation and recovery [ Time Frame: Nocturnal sleep on nights 1 & 2 (baseline), 3, 4, 5, 6 & 7 (first sleep manipulation period), 8 & 9 (first recovery period), 10,11,12, 13, 14 (second sleep manipulation period), & 15 (second recovery period) ]
    Percentage of nocturnal N3 sleep will be determined to establish baseline sleep characteristics (first and second night) and changes in the first sleep manipulation period (third, fourth, fifth, sixth, and seventh sleep) the first recovery period (eight and ninth night), the second sleep manipulation period (tenth, eleventh, twelfth, thirteenth, fourteenth), and the second recovery period (15th night)

  13. Change in the Rapid Eye Movement (REM) sleep duration at night with polysomnography from baseline nights to the first and second cycles of sleep manipulation and recovery [ Time Frame: Nocturnal sleep on nights 1 & 2 (baseline), 3, 4, 5, 6 & 7 (first sleep manipulation period), 8 & 9 (first recovery period), 10,11,12, 13, 14 (second sleep manipulation period), & 15 (second recovery period) ]
    Duration of nocturnal sleep REM sleep will be determined to establish baseline sleep characteristics (first and second night) and changes in the first sleep manipulation period (third, fourth, fifth, sixth and seventh sleep) the first recovery period (eight and ninth night), the second sleep manipulation period (tenth, eleventh, twelfth, thirteenth, fourteenth), and the second recovery period (15th night)

  14. Change in the Rapid Eye Movement (REM) sleep percentage at night with polysomnography from baseline nights to the first and second cycles of sleep manipulation and recovery [ Time Frame: Nocturnal sleep on nights 1 & 2 (baseline), 3, 4, 5, 6 & 7 (first sleep manipulation period), 8 & 9 (first recovery period), 10,11,12, 13, 14 (second sleep manipulation period), & 15 (second recovery period) ]
    Percentage of nocturnal sleep REM sleep will be determined to establish baseline sleep characteristics (first and second night) and changes in the first sleep manipulation period (third, fourth, fifth, sixth and seventh sleep) the first recovery period (eight and ninth night), the second sleep manipulation period (tenth, eleventh, twelfth, thirteenth, fourteenth), and the second recovery period (15th night)



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Ages Eligible for Study:   21 Years to 35 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • 21-35 years of age
  • Healthy
  • BMI between 18.5 and 24.9
  • Not habitual short sleepers
  • Not extreme chronotypes
  • Not a shift worker
  • Not a smoker
  • Daily consumption of ≤ 5 cups of caffeinated beverages
  • Weekly consumption of ≤ 14 units of alcohol
  • Do not intend to travel across > 2 time zones 1 month prior to the experiment
  • Not a fussy eater
  • Do not have any food allergy
  • No strict dietary requirements
  • No intention to lose or gain weight in the next 6 months
  • Not pregnant during the study
  • Do not have any metallic implants
  • Do not suffer from claustrophobia (last three inclusion criteria are only applicable for fMRI)

Exclusion Criteria:

  • The reverse of the inclusion criteria

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04731662


Contacts
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Contact: June Chi Yan Lo, Ph.D. +65 66016137 mdclocy@nus.edu.sg

Locations
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Singapore
MD 11- NUS Yong Loo Lin School of Medicine Recruiting
Singapore, Singapore, 117597
Contact: June Lo         
Sponsors and Collaborators
National University, Singapore
Investigators
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Principal Investigator: June Chi Yan Lo National University, Singapore
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Responsible Party: June Chi Yan Lo, Principal Investigator, Assistant Professor, National University, Singapore
ClinicalTrials.gov Identifier: NCT04731662    
Other Study ID Numbers: STAVAR
First Posted: February 1, 2021    Key Record Dates
Last Update Posted: May 10, 2021
Last Verified: May 2021
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by June Chi Yan Lo, National University, Singapore:
Glucose Metabolism
fMRI
Subjective Sleepiness
Neurobehavioral Functions
Cognitive Functions
Sleep Variability