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Updated: Dec 27, 2025
07:22
Using a Laminating Technique to Perform Confocal Microscopy of the Human Sclera
Published on: May 6, 2016
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Sclera color enhances gaze perception in humans
Jessica L Yorzinski1, Jacob Miller2
1Department of Ecology and Conservation Biology, Texas A&M University, College Station, Texas, United States of America.
Plos One
|February 29, 2020
Summary
Conspicuous eye morphology, particularly white sclera, enhances human gaze perception. This study found that people are faster and more accurate at detecting directed gazes when the sclera is conspicuous.
Area of Science:
- Evolutionary biology
- Cognitive neuroscience
- Ophthalmology
Background:
- Gaze perception is crucial for understanding attention.
- The influence of eye morphology on gaze perception is not well understood.
- Conspicuous sclera may have evolved to aid gaze following.
Purpose of the Study:
- To investigate if conspicuous eye morphology facilitates gaze perception in humans.
- To determine if the visibility of the sclera impacts the ability to detect directed gaze.
Main Methods:
- Human participants performed a visual search task.
- Eye movements were recorded during the task.
- Participants searched for faces with directed vs. averted gaze, varying in sclera conspicuousness and face size/orientation.
Main Results:
- Participants were faster and more accurate when searching for faces with conspicuous sclera compared to inconspicuous sclera.
- The effect was observed regardless of face size or orientation.
Conclusions:
- Conspicuous eye morphology, specifically the sclera, significantly facilitates gaze perception in humans.
- These findings suggest that eye morphology has evolved to enhance social communication through gaze following.
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