Evaluating How Well Different Types of Light-sensitive Cells in the Eye Contribute to Its Focusing Ability
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Color.
- Who it may be relevant to
- Registry conditions: Monochromatic, L- and S-cone Modulation Only, L- and M-cone Modulation Only, M and S-cone Modulation Only. Basic parameters: up to 35 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- United States
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
A Randomized, Repeated-measures Study to Evaluate the Contributions of Different Cone Photoreceptor Classes to a Step Ocular Accommodation Task
Overview
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.
Detailed description
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.
Interventions
- Other Color
Each 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 outcome measures
- 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).]
- 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).]
Eligibility criteria
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
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: Yes
Study design
- Allocation
- N/A
- Model
- Single group
- Masking
- Open label
- Primary purpose
- Basic science
Study locations
United States · 1 center
- Chester F. Carlson Center for Imaging Science — Rochester
Identifiers
NCT: NCT07691463 · IRB0000131-Exp1 · 4R00EY036497-03