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Age-related decline in function of ON and OFF visual pathways
Amithavikram R Hathibelagal1,2, Vishal Prajapati1,2, Indrani Jayagopi1,2
1Brien Holden Institute of Optometry and Vision Sciences, L V Prasad Eye Institute, Hyderabad, India.
Plos One
|March 22, 2022
Summary
This study developed a normative database for visual pathway function using an iPad application. Visual pathway responses, particularly for dark targets, significantly correlate with age, aiding in disease-specific defect quantification.
Area of Science:
- Ophthalmology
- Neuroscience
- Human Physiology
Background:
- A digital psychophysical paradigm on iOS devices can measure ON and OFF visual pathway function.
- An age-matched normative database for this paradigm is currently unavailable.
Purpose of the Study:
- To evaluate the response of ON and OFF visual pathways as a function of age.
- To establish a normative database for visual pathway function across different age groups.
Main Methods:
- 158 healthy adults (18-80 years) participated in the study.
- Monocular testing was performed using the 'EyeSpeed' application on an iPad.
- Participants identified light or dark targets, with reaction time, accuracy, and performance index recorded.
Main Results:
- Dark targets elicited significantly faster reaction times and higher accuracy compared to light targets.
- Both performance index and reaction time for all target types showed significant correlation with age.
- A significant correlation was observed between age and visual pathway function (p < 0.001).
Conclusions:
- The developed normative database is valuable for quantifying disease-specific visual defects.
- ON pathway function may serve as a surrogate marker for rod photoreceptor function.
- This study provides crucial data for understanding age-related changes in visual pathways.
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