A Randomized, Repeated-measures Study to Evaluate the Contributions of Different Cone Photoreceptor Classes to a Step Ocular Accommodation Task
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 20
- 试验地点
- 1
- 主要终点
- Accuracy of ocular accommodation
研究概览
简要总结
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.
详细描述
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.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- — 至 35 Years（Child, Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Between 18-35 years of age
- •Normal or corrected-to-normal (glasses/contact lenses) vision.
排除标准
- •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
研究组 & 干预措施
Color variation in visual stimulus
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.
干预措施: Color (Other)
结局指标
主要结局
Accuracy of ocular accommodation
时间窗: Each measurement takes 3 seconds. In the experiment, there will be two sessions, each lasting approximately 1 hour, on separate days. In each session, a total of 420 measurements will be taken.
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.
Speed of ocular accommodation
时间窗: Each measurement takes 3 seconds. In the experiment, the investigators will take measurements over the course of two sessions, each on separate days and lasting approximately 1 hour. During each session, 420 measurements will be collected.
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.
Accuracy of ocular accommodation
时间窗: 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.
Speed of ocular accommodation
时间窗: 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.
次要结局
未报告次要终点
研究者
Benjamin Chin
Assistant Professor
Rochester Institute of Technology