Effect of Visual Retraining on Visual Loss Following Cortical Damage
Overview
- Phase
- Not Applicable
- Intervention
- Not specified
- Conditions
- Vision Loss Partial
- Sponsor
- University of Rochester
- Enrollment
- 100
- Locations
- 1
- Primary Endpoint
- Change in Mean Direction Discrimination Threshold
- Status
- Recruiting
- Last Updated
- 9 months ago
Overview
Brief Summary
This project is intended to collect data using standard clinical tests and psychophysics to quantify the effect of visual cortical damage on the structure of the residual visual system, visual perception, spatial awareness, and brain function. The investigators will also assess the effect of intensive visual retraining on the residual visual system, processing of visual information and the use of such information in real-world situations following damage. This research is intended to improve our understanding of the consequences of permanent visual system damage in humans, of methods that can be used to reverse visual loss, and of brain mechanisms by which visual recovery is achieved.
Investigators
Krystel Huxlin
James V. Aquavella Professor of Ophthalmology, Associate Chair for Research, Dept. Ophthalmology
University of Rochester
Eligibility Criteria
Inclusion Criteria
- Not provided
Exclusion Criteria
- Not provided
Outcomes
Primary Outcomes
Change in Mean Direction Discrimination Threshold
Time Frame: Baseline to 8-12 months
For each subject, the investigators will measure the change in ability to detect differences in the motion direction of visual stimuli relative to horizontal, measured in degrees of visual angle with respect to the stimulus. These assessments will be based on what can be reliably detected at a 72-75% correct level of performance on our 2AFC task, with task difficulty adjusted on a 3:1 staircase. The degrees of visual angle for the stimulus vary from 90 degrees (fully vertical) to 0.1 degrees (virtually overlapping the horizontal axis). These measures of change will be evaluated baseline and at each subsequent visit to the laboratory; minimally from baseline to 4-6 months, then baseline to 8-12 months from start of training
Change in Mean Direction Integration Threshold
Time Frame: Baseline to 8-12 months
This will measure the change in ability of subjects to integrate across a range of motion directions measured in degrees of visual angle, with respect to the stimulus. These assessments will be based on what range of motion directions can be reliably integrated at a 72-75% correct level of performance on our 2AFC task, with task difficulty adjusted on a 3:1 staircase. The degrees of visual angle for the stimulus vary from 90 degrees (fully vertical) to 0.1 degrees (virtually overlapping the horizontal axis) . These measures of change will be evaluated baseline and at each subsequent visit to the laboratory; minimally from baseline to 4-6 months, then baseline to 8-12 months from start of training.
Change in Mean Contrast Sensitivity for Direction
Time Frame: Baseline to 8-12 months
Assessment of visual perception transfer to untrained psychophysical tasks of contrast sensitivity for direction discrimination. This is a change metric as transfer must be compared from pre- to post- each course of training. For each subject, the investigators will measure the ability to correctly detect the motion direction of visual stimuli that are also varying in contrast against a grey background. The investigators will measure the luminance contrast, measured in percentage of contrast with respect to the stimulus, that can be reliably detected at a 72-75% correct level of performance. Contrast will vary between 100% (maximum contrast of black on grey) and 0.1% (minimum contrast visible of grey-on-grey) based on subject performance and a 3:1 staircase. These measures of change will be evaluated baseline and at each subsequent visit to the laboratory; minimally from baseline to 4-6 months, then baseline to 8-12 months from start of training.
Change in Mean Contrast Sensitivity for Static Orientation
Time Frame: Baseline to 8-12 months
Assessment of visual perception transfer to untrained psychophysical tasks of contrast sensitivity for static orientation discrimination. This is a change metric as transfer must be compared from pre- to post- each course of training. For each subject, the investigators will measure the ability to correctly detect the orientation of non-moving visual stimuli that vary in contrast against a grey background. The investigators will measure the luminance contrast, measured in percentage of contrast with respect to the stimulus, that can be reliably detected at a 72-75% correct level of performance. Contrast will vary between 100% (maximum contrast of black on grey) and 0.1% (minimum contrast visible of grey-on-grey) based on subject performance and a 3:1 staircase. These measures of change will be evaluated baseline and at each subsequent visit to the laboratory; minimally from baseline to 4-6 months, then baseline to 8-12 months from start of training.
Secondary Outcomes
- Humphrey 10-2 and 24-2 perimetry(Baseline to 8-12 months)
- Goldmann perimetry(Baseline to 8-12 months)
- MAIA Visual Field Perimetry(Baseline to 8-12 months)