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Updated: May 27, 2026
10:41
Using Electroencephalography Measurements and High-quality Video Recording for Analyzing Visual Perception of Media Content
Published on: May 26, 2018
Asthenopia and blink rate under visual and cognitive loads.
Sowjanya Gowrisankaran1, Niru K Nahar, John R Hayes
1College of Optometry, The Ohio State University, Columbus, Ohio, USA. sowjanya@uic.edu
Summary
Increased cognitive load worsens eye strain symptoms, especially under poor visual conditions. This study found cognitive demands amplify visual stress effects during prolonged near work, impacting comfort and blink rates.
Area of Science:
- Ophthalmology
- Human Factors Engineering
- Cognitive Science
Background:
- Asthenopia, or eye strain, is commonly linked to visually demanding tasks.
- The role of cognitive load in exacerbating asthenopic symptoms remains unclear.
Purpose of the Study:
- To investigate how increased cognitive load, with and without visual stress, contributes to asthenopic symptoms during prolonged near work.
Main Methods:
- Thirty-three young adults performed near work tasks under varying visual (good quality, low contrast, refractive error) and cognitive load (video, fairy tales, technical articles) conditions.
- Subjects reported asthenopic, visual, and cognitive discomfort.
- Blink rate was measured using electromyography of the orbicularis oculi muscle.
Main Results:
- Higher cognitive load intensified symptoms under refractive error and low contrast visual conditions.
- Asthenopic symptoms were absent in cognitively demanding tasks with good visual quality.
- Blink rate decreased significantly under refractive error conditions during difficult reading tasks.
Conclusions:
- Cognitive and visual demands interact significantly, with higher cognitive loads amplifying symptoms typically caused by visual stressors.
- This highlights the importance of considering both factors in managing eye strain during near work.
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