Chester F. Carlson Center for Imaging Science
Rochester, New York, 14623, United States
Location status: Recruiting
Location contact
Benjamin M Chin, Doctorate
CONTACT
Benjamin M Chin, Doctorate
PRINCIPAL_INVESTIGATOR
Recruiting
NCT Number: NCT07691463
Evaluating How Well Different Types of Light-sensitive Cells in the Eye Contribute to Its Focusing Ability
In this experiment, subjects will view shapes on a screen with varying colors and be asked to focus their eyes on the shapes. The shapes will look as though they are jumping to random distances away from the eye. As the subjects focus their eyes on the shapes, the investigators will measure the focus of their eyes using a device called a wavefront sensor. This device uses infrared light to measure the optical properties of the eye in real time. Our goal is to find out how well the eye focuses on different colors. Our broad goal is to better understand how the eye focuses because that process is a major part of having clear and good vision.
Recruiting
Interested in participating?
Request InfoKey information
Conditions
Age range
Up to 35 year
Sex eligibility
All sexes
Study type
Interventional
Phase
Not applicable
Primary location
About this study
In this experiment, subjects will view Gabor patterns on a display through a Badal relay. The Gabor patterns will vary in their color. The colors will be picked to selectively modulate cone photoreceptor activity in different directions in cone contrast space. Subjects will be instructed to accommodate to the patterns while the virtual distance of the screen is manipulated with a focus-adjustable lens. As they do so, the investigators will measure the wavefronts of their eyes using a Shack-Hartmann wavefront sensor.
Who can participate
Healthy volunteers accepted: Yes
Only the study team can determine whether someone qualifies for participation.
Inclusion criteria
- Between 18-35 years of age
- Normal or corrected-to-normal (glasses/contact lenses) vision.
Exclusion criteria
- Vision worse than 20/20 while wearing glasses / contact lenses.
- Fragile or loose teeth (participants need to bite a piece of dental clay to stabilize their heads so that measurements can be taken from their eyes)
- Current pregnancy (experiment requires sitting down without moving for stretches of time)
- Heart disease
- Personal/familial history of epilepsy
Treatment and study plan
Color
OtherEach intervention involves showing a participant a stimulus with a particular color on a screen display, and asking the participant to focus their eyes on the stimulus. The 4 colors are: 1) grayscale (L, M, and S-cone modulation), 2) L and S cone modulation only, 3) L and M cone modulation only, and 4) M and S cone modulation only.
Primary outcomes
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Accuracy of ocular accommodation
Time frame: Because this is a basic science experiment, each measurement takes place at the same time as the intervention. There will be two sessions, each lasting approximately 1 hour, on separate days (day 1 and day 2).
Ocular accommodation is the focusing response of the lens in the eye. When the stimulus viewed by the participant changes in distance, the eye automatically refocuses. The investigators measure this refocusing using a device called a wavefront sensor. The investigators are particularly interested in how accurate this refocusing is, which is measured in units of diopters.
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Speed of ocular accommodation
Time frame: Because this is a basic science experiment, each measurement takes place at the same time as the intervention. There will be two sessions, each lasting approximately 1 hour, on separate days (day 1 and day 2).
The investigators are interested in how quickly the eye refocuses when a near object moves farther away. Typically, this process takes around 1 second, but it can take longer or shorter depending on the individual and on the object being viewed. By analyzing data collected by the wavefront sensor, the investigators will calculate how long it took for the eye to refocus during each measurement.
Study contacts
Contact information is provided by the study sponsor or research team.
Sponsors and collaborators
Lead sponsor
Rochester Institute of Technology
Other
Collaborators
- National Eye Institute (NEI)
Registry information
Official study title
A Randomized, Repeated-measures Study to Evaluate the Contributions of Different Cone Photoreceptor Classes to a Step Ocular Accommodation Task
Important dates
- Study start
- 2026
- Primary completion
- 2026
- Study completion
- 2026
- First posted
- Jul 9, 2026
- Registry last updated
- Jul 17, 2026
OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.
View the official ClinicalTrials.gov record (opens in a new tab)This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.