Project Summary
On the low vision continuum, the term ultra-low vision (ULV) defines vision good enough to be functional, but too
limited to see detailed shapes, even the largest letters on the eye chart at 50 cm (VA<20/1600 or 1.9 log MAR).
Approximately 1 million Americans currently suffer from severe visual impairment, and the number of individuals
with ULV is expected to grow, both due to an aging population and due to vision restoration treatments (e.g.,
retinal and cortical prosthesis, stem cell therapy, gene therapy) that restore vision from total blindness to the
ULV level. Indeed, the number of patients with ULV is expected to double by 2050. The current practice of visual
rehabilitation in ULV is based on sensory substitution training. However, can visual input enhance functional
performance using inputs from auditory and tactile senses? In this study we will evaluate the range of activities
that can be performed with different levels of ULV; for which of these activities multisensory integration can
enhance functional performance; test a pilot multisensory rehabilitation program; and develop and validate a
rehabilitation program for ULV based on multisensory integration. During the mentored phase, we will assess
visual performance using virtual reality (ULV lab at Johns Hopkins); use cue combination paradigms to assess
if there is enhancement of performance using multisensory integration (VisCog lab at University of Washington,
Seattle); and design and conduct a pilot multisensory rehabilitation program (CRIR at Université de Montreal,
Canada). During the independent phase, I will expand my training to develop an evidence-based multisensory
rehabilitation program for ULV that will be validated for use in ULV population. The outcomes of this research
will have important implications on improving visual ability and integration of visual, auditory and haptic senses.
A program better suited to ULV needs will have a significant impact on ULV individuals' quality of life. Currently,
individuals with ULV are not served well by the vision rehabilitation programs that are available, in part because
of the lack of tools to assess visual ability in any given ULV individual. People with ULV are generally encouraged
to ignore their remaining vision in order to strengthen their non-visual skills. Many of them find this frustrating
and unnecessary, become disillusioned, and avoid further rehabilitation training. Using the methods developed
in this study, we will be able to measure functional vision and validate a vision rehabilitation program for people
with ULV built on a multisensory approach. This study will bridge a critical knowledge gap in the field of
rehabilitation for people with ULV.