Non-visual Effects of Light
Conditions
Keywords
Light, Cognition, Alertness, Learning
Brief summary
The aim of the study is to examine the efficacy of supplementing sub-optimal ambient room lighting with a task lamp on working memory and procedural learning.
Interventions
DEVICEVisible light
Ambient room lighting will be supplemented with additional light from a task lamp.
Sponsors
Brigham and Women's Hospital
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
NONE
Intervention model description
Randomized crossover
Eligibility
Sex/Gender
ALL
Age
18 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
* Aged between 18-30 years; * Healthy (no medical, psychiatric or sleep disorders; * Non-smoking for at least 6 months; * Body Mass Index of \>18 or \<30 kg/m2; * Able to maintain 7-hour consistent sleep schedule during the study * Able to refrain from caffeine, alcohol, medication and supplements during the study
Exclusion criteria
* History of alcohol or substance abuse; * positive result on drugs of abuse urine toxicology; * Current or past history of sleep disorders, including but not limited to obstructive sleep apnea, narcolepsy, insomnia, or any significant sleep complaint * Psychiatric disorder, or first degree relative with a psychiatric disorder * Recent acute or chronic medical disorder * Use of drugs or medication (birth control OK) likely to affect sleep, alertness or light sensitivity, as determined by the investigators * Visual disorder, including but not limited to color blindness, or family history of glaucoma * Pregnancy or lactation * Shift work (\> 2 nights / week in the last 3 months and not during the study) * Transmeridian travel (2 or more time zones) in the past 3 months * Any other reason as determine by the Principal Investigator
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Working memory | 8 hour light exposure | Percent correct responses on a 2-minute mental arithmetic task |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Procedural learning | 8 hour light exposure | Percent change in the number of correct sequences on the Motor Sequence Task |
Other
| Measure | Time frame | Description |
|---|---|---|
| Memory recall | 8 hour light exposure | Percentage of correctly recalled words on a paired associates task |
| Vigilance | 8 hour light exposure | Reaction time and lapses on the Psychomotor Vigilance Task |
| Affect | 8 hour light exposure | Positive and negative affect scores assessed by the PANAS |
| Psychological distress | 8 hour light exposure | Total score on the Profile of Mood States (POMS) |
| Subjective sleepiness | 8 hour light exposure | Subjective sleepiness assessed by the Karolinska Sleepiness Scale - Scale from 1-9 where higher scores indicate greater sleepiness |
Countries
United States
Outcome results
None listed