Summary
This study demonstrates that suprathreshold corneal stimulation produces dose-dependent autonomic responses including pupil dilation, conjunctival redness, and increased accommodation, with chemical stimuli producing greater vascular responses than mechanical stimuli. For lighting researchers using pupillometry to assess melanopic or photic responses, these findings highlight that ocular surface nociception can independently drive pupil dilation, representing a potential confound.
Key Findings
- Pupil diameter increased dose-dependently with corneal stimulus intensity regardless of modality (mechanical or chemical); at 200% threshold, pupil diameter was significantly greater than all lower intensities (Tukey HSD, all p < 0.05)
- Female subjects showed greater pupil dilation than males at 150% and 200% threshold stimulus intensities (ANOVA p < 0.05)
- Chemical stimulation produced significantly greater conjunctival redness than mechanical stimulation at all stimulation levels (all Tukey HSD p < 0.05)
- Accommodation increased dose-dependently with stimulus intensity (ANOVA p < 0.05), with 200% threshold producing greater accommodation than all other intensities (Tukey HSD, all p < 0.05)
- No significant difference in pupil or vascular response was observed between the stimulated and unstimulated (contralateral) eye (all dependent t-test p > 0.05)
Categories
Eye Health & Vision: The study examines autonomic nervous system responses to corneal stimulation, including pupillary reflexes, conjunctival blood flow, and accommodation — all relevant to ocular health assessment.
The Science of Light: Pupil diameter changes in response to noxious stimuli are quantified, providing baseline data on non-photic pupillary responses relevant to interpreting pupillometry in lighting research.
Author(s)
E Alabi
Publication Year
2018
Number of Citations
2
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The Science of Light
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- Diminished pupillary light reflex at high irradiances in melanopsin-knockout mice
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