Projects

Neurodynamics of Braille Reading

[Under construction]

Neuroimaging techniques such as EEG/MEG and fMRI offer the potential to trace the propagation of Braille information through the brain as it transforms from a dot pattern to meaningful alphabetic information, and comparing this to the analogous processing stream of printed letters in sighted people.

Novel Method to Teach Scotoma Awareness

This project aims to improve visual function in individuals with age-related macular degeneration (AMD). AMD isassociated with central field loss that cannot be corrected optically. Individuals with AMD are often unaware of their scotoma and their eye movements follow more random patterns, compared to adults with healthy vision. With funding from the National Institutes of Health and Pacific Vision Foundation, we are training indviduals with AMD to direct their eye movements into their scotoma, so that they can sample missing information.

 

Oculomotor Control

The binocular coordination of movements of the eyes is a complex issue controlled by many brainstem nuclei, and is subject to a wide variety of forms of disruption by traumatic brain injury and oculomotor muscles disorders. The goal of this project is to characterize the natural range of the dynamics of the binocular ocuomotor system and their widespread disruptions across the spectrum of human ocolumotor control.

overTHERE

overTHERE is a virtual Talking Signs iPhone app for blind and visually-impaired pedestrians that demonstrates a powerful audio/haptic interface to location information about businesses and other points of interest.

Parafoveal Crowding

Crowding increases with eccentricity, and is most readily observed in the periphery. During natural, active vision however, central vision plays an important role. Measures of critical distance to estimate crowding are difficult in central vision, as these distances are small. Any overlap of flankers with the target may create an overlay masking confound. The crowding factor method avoids this issue by simultaneously modulating target size and flanker distance and using a ratio to compare crowded to uncrowded conditions. This method was developed and applied in the periphery (Petrov &…

Patterns of Visual Deficits in Amblyopia

Background Amblyopia means blunted sight in the Greek language and is a term clinicians use to describe decreased vision usually in one eye most commonly due to a focusing error (refractive error in one eye, very different from other eye - anisometropia) and/or a misalignment between the two eyes (strabismus or squint). Amblyopia is sometimes called “lazy eye”. This is different than being just near or far sighted which is a refractive error usually similar and in both eyes developing at any age and vision improves instantly on prescribing and wearing spectacles to correct the error.