Projects

Expanded Populations Research Agenda for Description (EPRAD)

Bridge Multimedia is collaborating with the VDRDC and the DLN to develop EPRAD, a research road map to identify the critical questions that will improve our evidence-based understanding of how description may apply to the education of students with non-visual disabilities such as ADHD and autism.

 

Bridge’s work on the Expanded Populations Research Agenda for Description (EPRAD) will identify the concrete research questions necessary to quantitatively assess the value of description for these expanded populations. EPRAD also dovetails with the Visual-Impairment Research Agenda for Description…

Eye Movements and Accommodation Patterns in Neurotypicals, Strabismus and other Eye Conditions

Strabismus misaligned eyes is a common developmental condition in young children that can lead to amblyopia or poor vision and other forms of low vision. This project looks at the eye movements in relation to accommodation or focusing power in these patients to determine predictors of strabismus and outcome of treatment, with the goal of improving early detection, intervention and treatment.

Fixational and Functional PRL in Central Vision Loss

Individuals with central vision loss (commonly due to age-related macular degeneration), must use viewing strategies using peripheral vision. Patients often adopt a preferred retinal locus (PRL) for visually guided behavior. While the are clinical measures for estimating the PRL, little is known about use in the real world. Our research seeks to characterize this natural behavior and inform visual rehabilation techniques.

Focal Attention and Letter Recognition

We studied letter recognition in 8 deg eccentricity from the fovea after attracting sustained focal attention to the stimulated location by a cue. Young and elderly healthy subjects, as well as patients with central vision loss participated. We found that the ability to utilize focal attention has an irregular topographic component in some subjects. The experiments in patients indicated that locations with high attentional potential are more likely to be used as preferred retinal loci after central vision loss.

 

References

MacKeben, M. (1999) Sustained Focal Attention and Peripheral Letter…

Fovea Use During Smooth Pursuit

There is continuing debate as to whether smooth pursuit relies on the foveation of a moving target, especially when the target is compact. Previous studies have shown that gaze is placed on the center-of-mass of a target during saccadic eye movements. This research aims to understand whether eye placement is similarly centered during smooth pursuit and whether foveation is necessary for pursuing a small stimulus.  

Functional Assessment - Book Chapters

Categorization of visual functioning requires appropriate measurement methods.  Dr. Colenbrander has discussed the principles of functional assessment in several book chapters.

            Measuring Vision and Vision Loss, Vol. 5, chapter 51, in Duane’s Clinical Ophthalmology, (2001, updated and expanded for 2010 edition).   Comprehensive overview, 96 pages, 10 MB.   PDF

            Low Vision Rehabilitation, Special issue of: Ophthalmology Clinics of North America, Colenbrander, Fletcher eds., 7, 2, 1994.

            The Visual System.  Chapter 12 in Master the AMA Guides (L. Cocchiarella, S.J…

Functional Assessment - Contrast Sensitivity

For eye doctors measuring contrast sensitivity loss during routine eye exams is not a priority, since contrast losses are not disease specific and do not guide treatment decisions. 
For the patient, on the other hand, knowledge about contrast losses, of which they are usually not consciously aware, is very important, since it may affect the performance of Activities of Daily Living and affect safety in mobility tasks.

When visual parameters are measured, the measurements are usually limited to determining peak contrast sensitivity and threshold visual acuity as separate, seamingly independent…