Time is Vision: Properties of Vision Early after Occipital Stroke and Capacity for Recovery

Thesis (Ph.D.)--University of Rochester. School of Medicine & Dentistry. Dept. of Translational Biomedical Sciences, 2020.Cortical blindness (CB) is a common sequela after stroke affecting primary visual cortex, presenting as a contralesional, homonymous visual field cut. It is widely assumed that, after a brief period of spontaneous improvement, the vision loss becomes stable and permanent. Yet, there is recent evidence for partial visual recovery in chronic (>6 months) CB, though this requires lengthy training and the vision restored is not entirely normal. Little is known about the properties of vision loss early after stroke, and whether earlier training can promote greater visual recovery. In contrast, in sensorimotor stroke, early rehabilitation is thought most effective. Here, we begin addressing these questions by first quantifying the natural history of visual field loss after stroke using a retrospective review of UR patients from 2011-2019. New analytical methods applied to Humphrey automated perimetry verified that spontaneous improvements in visual detection abilities could occur initially after stroke, but beyond 6 months, visual sensitivity did not stabilize; instead, it worsened. Moreover, psychophysical tests showed that subacute (