This document summarizes research on sleep conducted by summer interns. It discusses the circadian rhythm and how sleep affects performance, mood, and alertness. The interns studied sleep quality metrics and results from psychomotor vigilance tests (PVTs) taken on different devices. Their results showed that PVTs taken on an actiwatch with it on were comparable to laptop tests, while tests on tablets need more evaluation. The interns concluded more research is needed on actiwatch vs device comparisons and thanked those who oversaw their work.

1. SLEEP:
You Need It
NPS Summer Interns
Operations Research Department
Presented by
Joshua Strubel, NREIP
Amanda Vanecko, NREIP

2. Overview
Sleep 101
Sleep and the Military
Our Research
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3. Sleep 101: The Circadian Rhythm
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4. Sleep 101: The Circadian Rhythm
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Circa – “about”, diem –
“day”
Circadian – a cycle the
occurs within about a day
or a 24 hour period
Most systems in the human
body follow a circadian
rhythm.
This rhythm can be affected by sleep
deprivation
Changes in this rhythm can affect an
individual’s performance

5. Sleep and Performance
• Behavior
• Mood
• Alertness
Losing sleep creates “sleep debt”
How much sleep should you get?
Adults: 7-8 hours
Young Adults: 8-9 hours
Teenagers: 9-10 hours
Effects of sleep deprivation
• Performance
• Cognitive
function
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6. Sleep Data Actigram
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7. Our Research
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Psychomotor Vigilance Tests (PVTs) assess performance
and reaction time
Watch A Watch B
Tablet

8. Data Analysis
Metrics for Sleep Quality:
• Pittsburg Sleep Quality Index
• Epworth Sleepiness Scale
• Sleep watch actigrams
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• % of False Starts (FS)
• % of 355ms Lapses + FS
• % of 500ms Lapses + FS
Metrics for PVT Results:
• Reaction Time (RT)
• Response Speed (1/RT)
• Fastest 10% of RT
• Slowest 10% of 1/RT
Data evaluated in matched pairs (by participant and day)
Wilcoxon Rank Sum Test

9. Our Results
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0.00%
10.00%
20.00%
30.00%
40.00%
50.00%
60.00%
70.00%
<150 150-200 200-250 250-300 300-350 >350
PercentofResponses[%]
Mean Reaction Time [ms]
Mean Reaction Time by Device
Actiwatch Off
Actiwatch On
Laptop
Tablet

10. 10
Laptop Watch Off Watch On Laptop Tablet
Day 1 Day 2
AverageResponseSpeed
7
6
5
4
3
2
Average Response Speed by Device

11. Conclusions and Next Steps
Actiwatch On is comparable
to laptop-based PVT
Tablet PVT needs
further evaluation
Potential area for
future research
Actiwatch Off is not comparable

12. Acknowledgments
For their encouragement and oversight, we would like
to give a special thanks to:
Dr. Nita Shattuck
Dr. Panagiotis Matsangas
Heather Temple
Thanks also to our fellow interns for their hard work:
Raymond Garcia, North Salinas High School
Cynthia Jones, Marina High School
Isaac Yoon, Doughtery Valley High School
Jenny Lafayette, Santa Catalina School

13. Questions?
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14. Top 10 Sleep Tips:
1. Own comfortable bedding
• Mattress, Pillow, Sheets, Comforter/Blanket(s)
2. Manage light exposure to control circadian
rhythm
3. Avoid late alcohol, cigarettes, and heavy meals
4. Practice calming techniques to wind down
• Yoga, Meditation, Warm bath or shower
5. If not sleepy, go to another room and relax
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15. Top 10 Sleep Tips:
6. Keep a consistent to a sleep schedule
7. Bedtime Ritual
• Eg. Wash up, yoga, lights out, silence phone, bed
8. If you have trouble sleeping avoid naps
9. Exercise daily
10. Make room appropriate for sleep
• Manage noise, light exposure, distractions, etc
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16. Actigram
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