Dose-dependent Impact of Daytime Lighting on Evening Responses to Light

The purpose of this study is to systematically examine the impact of different intensities of daytime light and the subsequent impact that such exposure has on non-image forming responses to light in the evening.

Study Overview

• Status: Not yet recruiting
• Conditions: Sleep
• Intervention / Treatment: Behavioral: Light

• Study Type: Interventional
• Enrollment (Anticipated): 48
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Jamie Zeitzer, PhD; Phone Number: 6504935000; Email: jzeitzer@stanford.edu

Study Locations

• United States
  • California
    • Palo Alto, California, United States, 94304
      • VA Palo Alto Health Care System

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Aged 18-65
2. Good health
3. Male or female
4. Normal color vision

Exclusion Criteria:

1. Sleep disorders
2. Extreme chronotypes
3. Routine smoker
4. Significant hearing loss
5. Depressed
6. Alcohol use disorder
7. Use of illegal drugs

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Low room; Low intensity (80 lux) room light	Behavioral: Light; 10 hours of light exposure during the daytime, starting 2 hours after habitual wake time
Experimental: Normal room; Normal intensity (150 lux) room light	Behavioral: Light; 10 hours of light exposure during the daytime, starting 2 hours after habitual wake time
Experimental: Bright room; High intensity (500 lux) room light	Behavioral: Light; 10 hours of light exposure during the daytime, starting 2 hours after habitual wake time
Experimental: Bright; Very high intensity (1000 lux) room light	Behavioral: Light; 10 hours of light exposure during the daytime, starting 2 hours after habitual wake time

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Suppression of melatonin production	Difference in salivary melatonin concentrations between active arm and 3 lux control condition	4 hours
Phase shift in the timing of melatonin onset	Change in the onset of melatonin secretion after experimental stimulus	2 days

Collaborators and Investigators

• Sponsor: Palo Alto Veterans Institute for Research

Study record dates

Study Major Dates

• Study Start (Anticipated): July 1, 2022
• Primary Completion (Anticipated): June 1, 2024
• Study Completion (Anticipated): July 1, 2024

Study Registration Dates

• First Submitted: May 7, 2021
• First Submitted That Met QC Criteria: May 7, 2021
• First Posted (Actual): May 11, 2021

Study Record Updates

• Last Update Posted (Actual): March 17, 2022
• Last Update Submitted That Met QC Criteria: March 2, 2022
• Last Verified: March 1, 2022

More Information

Terms related to this study

• Other Study ID Numbers: Reverse DRC

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No