Evaluating How Well Different Types of Light-sensitive Cells in the Eye Contribute to Its Focusing Ability

NCT07691463 | Recruiting

• 2 other identifiers: IRB0000131-Exp14R00EY036497-03
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Monochromatic; L- and S-cone Modulation Only; M and S-cone Modulation Only; L- and M-cone Modulation Only

Keywords

Ocular accommodation; Visual acuity; Physiological optics; Visual psychophysics; Color science

Outcome Measures

Primary Outcomes (2)

• Accuracy of ocular accommodation

  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.

  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

  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.

  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).

Study Arms (1)

Color variation in visual stimulus

EXPERIMENTAL

Each participant undergoes all experimental conditions, in a within-subjects design. Each intervention corresponds to a different stimulus color. 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.

Other: Color

Interventions

Color OTHER

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.

Color variation in visual stimulus

Eligibility Criteria

• Age: Up to 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• Between 18-35 years of age
• Normal or corrected-to-normal (glasses/contact lenses) vision.

You may not qualify if:

• 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

Sponsors & Collaborators

• Rochester Institute of Technology: lead
• National Eye Institute (NEI): collaborator

Study Sites (1)

Chester F. Carlson Center for Imaging Science

Rochester, New York, 14623, United States

RECRUITING

MeSH Terms

Interventions

Color

Intervention Hierarchy (Ancestors)

Light; Optical Phenomena; Physical Phenomena

Central Study Contacts

Benjamin M Chin, Doctorate

CONTACT

8454534320; bmccis@rit.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Study Record Dates

• First Submitted: June 30, 2026
• First Posted: July 9, 2026
• Study Start: July 2, 2026
• Primary Completion (Estimated): December 15, 2026
• Study Completion (Estimated): December 15, 2026
• Last Updated: July 17, 2026

Record last verified: 2026-07

Locations

US (1)