Pre-sleep blue light exposure alters resting-state EEG without affecting melatonin or next-morning cognitive performance in adolescents

Effect of difference duration of blue light exposure before bedtime on EEG, melatonin, cognitive performance in adolescents : randomized crossover design

Status

Active, not recruiting

Phases

Phase 1

Study type

Interventional

Source

TCTR

Registry ID

TCTR20260506006

Enrollment

Registered

2026-05-06

Start date

2022-06-30

Completion date

Unknown

Last updated

2026-08-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

The effect of different durations of pre-sleep blue light exposure influences adolescent sleep, melatonin level and next-day functioning. Sleep parameters, EEG, visual reaction time, working memory, and attentional performance.

Interventions

Non-screen-based activity (e.g., board game) ,Participants were exposed to screen light via a tablet device from 21:30 to 23:00 h,Participants were exposed to screen light from 20:00 to 23:00 h.

No Intervention No treatment,Experimental No treatment,Experimental No treatment

Control group,90-min BL,180-min BL

Eligibility

Sex/Gender

Male

Age

18 Years to 24 Years

Inclusion criteria

Inclusion criteria: 1. Twelve healthy male university students (18-24 years old) 2. All participants were non-smokers, free from neurological, psychiatric, or major medical conditions. 3. Had normal or corrected to normal vision without color blindness. 4. Regular sleep-wake patterns (bedtime before 23:00 h. sleep duration 7-8 h. 5. Good sleep quality (PSQI greater than or equal to 5)

Exclusion criteria

Exclusion criteria: 1. Have a shift work within the previous three months or traveled across time zones within four weeks were excluded. 2. Substance use. 3. Excessive caffeine intake (>3 cups/day). 4. Extreme chronotype.

Design outcomes

Primary

Measure	Time frame
Salivary melatonin concentration at 20.00 pm,21.30 pm, and 23.00 pm (every conditions) Collected saliva samples ,Brain waves recorded the following morning (every conditions) Electroencephalography (EEG),Visual reaction time (VRT) The following morning (every conditions) Visual oddball paradigm,Working memory The following morning (every conditions) Digit Span Forward test.,Executive function and processing speed The following morning (every conditions) Trail Making Test- parts A (TMT-A) and B (TMT-B)	—

Measure

Time frame

Salivary melatonin concentration at 20.00 pm,21.30 pm, and 23.00 pm (every conditions) Collected saliva samples ,Brain waves recorded the following morning (every conditions) Electroencephalography (EEG),Visual reaction time (VRT) The following morning (every conditions) Visual oddball paradigm,Working memory The following morning (every conditions) Digit Span Forward test.,Executive function and processing speed The following morning (every conditions) Trail Making Test- parts A (TMT-A) and B (TMT-B)

—

Secondary

Measure	Time frame
Sleepiness level at 20.00 pm,21.30 pm, and 23.00 pm (every conditions) Karolinska Sleepiness Scale (KSS),Sleep parameters Throughout the night wrist-worn actigraphy	—

Countries

Thailand

Contacts

Public ContactTisanamadee Silae

Kasetsart University

tisanamadeee@gmail.com0909864878

Outcome results

None listed

Source: TCTR (via WHO ICTRP) · Data processed: Aug 10, 2026