About this trial
This study tests whether a week of morning bright light therapy changes how well healthy young adults sleep and how alert, positive, and mentally sharp they feel during the day.
Morning light is the body's main signal for keeping its internal clock and sleep-wake timing on track. Many university students keep irregular hours and spend most of the day indoors, where light is far dimmer than daylight. This study asks whether adding a short, bright morning light session can help.
Each participant takes part for two weeks. For one week they use a bright light box for 30 minutes each morning, shortly after waking; for the other week they keep their usual lighting. The order of the two weeks is decided at random, and each person serves as their own comparison.
Throughout both weeks, sleep is tracked with a wrist-worn Fitbit and a short daily diary. Participants also rate their sleepiness and mood, complete brief computer-based attention and memory tasks, and take part in a short interview at the end about their experience.
The study compares the bright-light week with the usual-light week to see whether morning bright light improves sleep regularity and efficiency, reduces daytime sleepiness, lifts mood, or affects thinking performance. The trial is being conducted in waves; a first wave has completed and a second wave is planned, pending additional funding.
Eligibility criteria
Qualifiers
Enrolled university student
Aged 18 years or older
Generally healthy, with no diagnosed sleep disorder (sleep quality screened using the Pittsburgh Sleep Quality Index)
Residing in shared student housing
Disqualifiers
Diagnosed insomnia or other diagnosed sleep disorder
Other medical, psychiatric, or neurological condition that could affect sleep, mood, or cognition
Trial design
Treatments tested in this trial
- Bright light therapy (10,000 lux light box)
Treatment groups
Sponsors and collaborators
The Hong Kong Polytechnic University
Lead sponsor
Northumbria University
Collaborator