How Lighting Conditions Affect Eye Focus When Reading a Book

Completed

• Conditions: Healthy human participants who all can read.

• Registration Number: CTRI/2025/03/083170
• Lead Sponsor: NonApplicable

Brief Summary

This experimental study aims to evaluate the impact of different illumination levels on ocular accommodation during paper-based reading in healthy adults. Participants will undergo reading tasks under varying light intensities while assessing changes in **accommodative response, visual fatigue, and reading performance**. Primary outcomes include **accommodative amplitude, lag, and facility**, while secondary outcomes focus on **reading speed, comprehension, pupil dynamics, and subjective discomfort**. Measurements will be taken **before, during, and after reading**, with short-term recovery assessments. Findings will help determine optimal lighting conditions to minimize visual strain and enhance reading efficiency, contributing to improved environmental lighting recommendations.

Detailed Description

Not available

Study Timeline

• Study Start: 2025-01-05
• Last Update Posted: 2025-03-19
• Study Completion: 2025-06-26

Recruitment & Eligibility

• Status: Completed
• Sex: All
• Target Recruitment: 34

Inclusion Criteria

• University adults aged 17-24 years 2.
• Aided visual acuity 20/20 for both near and distance 3.
• Normal binocular vision parameters.

Exclusion Criteria

• Presence of ocular diseases or conditions affecting accommodation & dry eye 2.
• History of ocular surgery 3.
• Current use of medications affecting ocular function 4.
• Not willing to participate 5.
• Contact lens wearer.

Study & Design

• Study Type: Observational
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
This study will evaluate how different lighting levels affect ocular accommodation during paper-based reading. Accommodation amplitude, lag, and facility will be measured using autorefractors or dynamic retinoscopy, while visual fatigue symptoms like eye strain, headache, and discomfort will be assessed through questionnaires. The goal is to identify optimal lighting to improve accommodation efficiency and visual comfort in healthy adults.	Base line- 1 week

Secondary Outcome Measures

Name	Time	Method
The secondary outcome of this study will focus on additional visual & reading performance parameters influenced by different illumination levels. These include reading speed & comprehension, assessed through standardized reading tests, as well as subjective visual comfort, measured via validated questionnaires. Additionally, pupil diameter changes & blink rate may be recorded to analyze physiological responses to lighting variations. The study will also evaluate the persistence of visual fatigue over time by tracking accommodative recovery post-reading. These outcomes will provide a broader understanding of how lighting impacts overall visual efficiency & reading performance in healthy adults.	1. Base line- 1 week

Trial Locations

Locations (1)

Noida International University; 🇮🇳 Nagar, UTTAR PRADESH, India

Noida International University

🇮🇳Nagar, UTTAR PRADESH, India

Roshni Majumder

Principal investigator

7086151146

roshni.majumder98@gmail.com

Vishal Biswas

Principal investigator

8420961195

vishalbiswas45@gmail.com