Sleep Variability
Conditions
Brief summary
Daily sleep variability is prevalent in the young populations, yet its effects remain less clear. The experimental study aims to examine the impacts of intraindividual daily sleep variability on sleep characteristics, cardiometabolic regulations and daytime functioning in college students.
Interventions
BEHAVIORALIrregular sleep
Experimental-induced sleep variability
Sponsors
The University of Hong Kong
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 25 Years
Healthy volunteers
Yes
Inclusion criteria
* Habitual sleep duration \> 7 h/day.
Exclusion criteria
* Extreme morning- nor extreme evening-chronotype * With sleep problems * With mood and anxiety problems * With excessive daytime sleepiness * Have history of any chronic medical condition and on regular medication.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Cognitive functioning - working memory | 7 days | working memory as measured by 2-back task |
| Mood | 7 days (every morning and evening) | mood state as measured by the Positive and Negative Affect Scale (PANAS). |
| Cognitive functioning - Sustained attention | 7 days (every morning and evening) | Sustained attention as measured by psychomotor vigilance task (PVT) |
| Cognitive functioning - processing speed | 7 days | Processing speed as measured by Digit Symbol Substitution Test (DSST) |
| Cognitive functioning - inhibition | 7 days | Inhibition as measured by stop-signal reaction time (SSRT) |
| Subjective sleepiness | 7 days (every morning and evening) | As measured by the Stanford Sleepiness Scalen (SSS) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Sleep architecture | 7 days | Sleep stagings (e.g., SWS%, REM duration) and sleep EEG spectrums as analysed from PSG recordings. |
| Heart rate variability | 7 days | Resting heart rate and heart rate variability are measured in the morning, evening and during the night. |
| Cortisol awakening response | baseline, post-intervention | Cortisol awakening response is assessed before and after the manipulation. |
| Sleep quality | 7 days | Actual sleep time, sleep onset latency, wake after sleep onset and night time arousals as measured by actigraphy and PSG. Sleep satisfactory and dreams as measured by sleep diary. |
Countries
Hong Kong
Outcome results
None listed