Clinical Research Directory

Hemianopsia Rehabilitation After Stroke or Brain Injury

In patients with hemianopsia following stroke or brain injury, we will determine if stimulating the visual field with images from a PowerPoint slide set can increase the visual field.

Improving Visual Field Deficits With Noninvasive Brain Stimulation

This is a randomized, pilot interventional study in participants with visual field deficit (VFD) caused by cortical lesion. Damage to the primary visual cortex (V1) causes a contra-lesional, homonymous loss of conscious vision termed hemianopsia, the loss of one half of the visual field. The goal of this project is to elaborate and refine a rehabilitation protocol for VFD participants. It is hypothesized that visual restoration training using moving stimuli coupled with noninvasive current stimulation on the visual cortex will promote and speed up recovery of visual abilities within the blind field in VFD participants. Moreover, it is expected that visual recovery positively correlates with reduction of the blind field, as measured with traditional visual perimetry: the Humphrey visual field test or an eye-tracker based visual perimetry implemented in a virtual reality (VR) headset. Finally, although results will vary among participants depending on the extent and severity of the cortical lesion, it is expected that a bigger increase in neural response to moving stimuli in the blind visual field in cortical motion area, for those participants who will show the largest behavioral improvement after training. The overarching goals for the study are as follows: Group 1a will test the basic effects of transcranial random noise stimulation (tRNS) coupled with visual training in stroke cohorts, including (i) both chronic/subacute ischemic and chronic hemorrhagic VFD stroke participants, and (ii) longitudinal testing up to 6 months post-treatment. Group 1b will test the effects of transcranial tRNS coupled with visual training on a Virtual Reality (VR) device in stroke cohorts, including both chronic/subacute ischemic and chronic hemorrhagic VFD stroke participants. Group 2 will examine the effects of tRNS alone, without visual training, also including chronic and subacute VFD stroke participants and longitudinal testing.

Statistical Learning as a Novel Intervention for Cortical Blindness

This project aims to develop a novel visual training paradigm for use in visually-intact participants and those sufferings from stroke-induced visual impairments. Our task design is built upon theories of statistical learning to reduce the overall training burden while still producing profound improvements to visual abilities. Efficacy will be first established in visually-intact controls before testing in stroke survivors to assess the feasibility of this form of learning in the damaged visual system.

Vision Loss Impact on Navigation in Virtual Reality

The purpose of this research is to better understand the impact of cortically-induced blindness (CB) and the compensatory strategies subjects with this condition may develop on naturalistic behaviors, specifically, driving. Using a novel Virtual Reality (VR) program, the researchers will gather data on steering behavior in a variety of simulated naturalistic environments. Through the combined use of computer vision, deep learning, and gaze-contingent manipulations of the visual field, this work will test the central hypothesis that changes to visually guided steering behaviors in CB are a consequence of changes to the visual sampling and processing of task-related motion information (i.e., optic flow).

Visual Rehabilitation After Occipital Stroke

This research aims to examine changes in plastic potential of the visual system with time from stroke affecting primary visual cortex. We will measure structural and mechanistic aspects of progressive degeneration along the early visual pathways, correlating them with changes in visual performance, and in responsiveness to visual restoration training. This project will advance both scientific knowledge, as well as technical capability and clinical practices for restoring vision and quality of life for people suffering from cortical blindness.

Feasibility Test of Virtual Reality Obstacle Detection for Low Vision Walking

The investigators are developing a new test of pedestrian hazard detection in virtual reality (VR) head-mounted display (HMD) headset, which shows virtual oncoming pedestrians in 3D while subjects are walking in real-world environment, for evaluation of visual field expansion to improve mobility in people with visual field loss.

Feasibility Tests for Various Prism Configurations for Visual Field Loss

The investigators will develop and test different configurations of high-power prisms to expand the field of vision of patients with visual field loss to assist them with obstacle detection when walking. The study will involve multiple visits (typically four) to Schepens Eye Research Institute for fitting and testing with the prism glasses. The overall objective is to determine best designs and fitting parameters for implementation in prism devices for future clinical trials.

Visual Plasticity Following Brain Lesions

The VIBRANT (Vision Improvement through Behavioral Rehabilitation And Neuroplasticity Training) study is a prospective, double-blind, crossover design (within-subject) in participants with homonymous hemianopia-a type of visual field loss resulting from damage to the post-chiasmatic visual pathways. It aims to investigate whether transcranial random noise stimulation (tRNS) combined with perceptual learning-based training has potential for improving visual impairments.

Virtual Reality Visual Field Testing as an Alternative in Childhood Eye Disease

The purpose of this study is to test a new way of measuring the peripheral vision (called a visual field test) using a device which can be worn as goggles rather than being a large instrument the patient must sit at. This new visual field test (called VisuALL) is an FDA-approved virtual reality system which has been used in adults and children. This study will compare the performance of the VisuALL to the standard testing for peripheral vision, which is called the Humphrey Visual Field (HVF) test. The study will recruit both healthy children, as well children and young adults who have eye conditions which require visual field testing as part of their standard care. The test will be performed on a day when the child or young adult already has a scheduled eye appointment as standard care. The test does not touch the eyes or require any eye drops to be given, and there is no known risk associated with the test itself. There may be a risk of loss of confidentiality. Participating in this study will require approximately 30 minutes, has no extra cost associated with it, and will be compensated by a parking pass for the day of the visit. There are no direct benefits for participants. Selected participants will be also be given training and then loaned a home VisuALL system to allow home visual field testing. If your child is selected, additional information would be provided.