• The Macular Search Test

    We introduced a novel approach to topographic function assessment in visual impairment that requires neither fixation nor reading.

  • Completed

    The Smith-Kettlewell Haptics Symposium

    Date: Thursday, March 29, 2018

  • Completed

    The Window of Spatial Attention in Reading

    We investigate the dynamics of spatial attention while the eyes move around to gather information.

  • Active

    Tracking a target in depth with central field loss

    Bilateral field loss due to maculopathy creates a scotoma that extends in depth — a volume scotoma.

  • Completed

    Tutorials and Reference

    These are tutorials and reference materials I have written on various topics in probability and geometry over the years.

  • Completed
    One person looking directly at another person and picking up a cup by the handle, illustrating peripheral stereopsis

    Upper Depth Limit Across Visual Field

    Stereopsis is important for tasks of daily living such as eye-hand coordination. It is best in central vision but is also mediated by the periphery. Previously we have shown that individuals with central-field loss who have residual stereopsis in the periphery perform better at an eye-hand-coordination task. Here we sought to determine what sets the limit of stereopsis, defined as the largest disparity that supports the sustained appearance of depth, in the near periphery in healthy individuals. We used a rigorous method to determine the uppermost limit of disparity. The disparity limit is the point at which the threshold for judging dichoptic separation between the half-images is equal to the monocular width-discrimination threshold. The disparity limit at 10° was a factor of 2–4 times larger than the fovea, regardless of the meridian tested. The increase in the disparity limit with eccentricity was shallow, similar to that of Panum's area. Within this disparity limit, disparity increment thresholds were comparable for foveal and peripheral targets, illustrating the significance and utility of peripheral stereopsis, especially in the absence of foveal stereopsis.

  • Video Description Research and Development Center

    The Smith-Kettlewell Video Description Research and Development Center (VDRDC) investigates innovative technologies and techniques for making online video more accessible to blind and visually-impaired students and consumers.

  • Completed

    Video-Based Speech Enhancement for Persons with Hearing and Vision Loss

    Observing the visual cues from a speaker such as the shape of the lips and facial expression can greatly improve the speech comprehension capabilities of a person with hearing loss. However, concurrent vision loss can lead to a significant loss in speech perception. We propose developing a prototype device that utilizes a video camera in addition to audio input to enhance the speech signal from a target speaker in everyday situations.

  • Visual Cortical Function in Very Low Birth Weight Infants


    Preterm infants are at high risk of visual and neural developmental deficits. We used swept parameter visual evoked potential (sVEP) to determine whether premature birth alters visual cortical function.

  • Visual-Impairment Research Agenda for Description (VIRAD)

    A systematic road map charting gaps in the quantitative evidence about how description can and should be used to improve video accessibility for the blind.