Funded Grants

The brain as a flexible, sensory-modality-independent task machine: From basic research to visual rehabilitation

Severe visual impairments affect over 200,000,000 people worldwide. My lab studies these impairments as a model for answering fundamental questions in cognitive neuroscience. Our work spans the gamut from basic science, querying brain plasticity and sensory integration, to cutting-edge technological developments, allowing blind persons to “see” with sensory substitution devices (SSDs). These devices code visual information and represent it using sound or touch. We aim to augment impaired vision, and even help restore vision using SSDs. We have recently shown, using SSDs, that at least two key visual brain areas are in fact highly flexible, modality-independent (and even visual-experience independent) task machines. Here we further hypothesize that all visual areas can process sound and touch to the same extent as they process vision, but only when subjects learn to extract all the relevant information (depth, facial features, etc.) encoded by these alternative senses.

We propose that, with proper training, any brain area can change the type of sensory input it uses to retrieve task-relevant information within a matter of days. Based on the insights gained so far using veteran SSDs, we propose to develop several innovative SSDs which will encode the most crucial aspects of vision and make them accessible to the blind, along with targeted, simple training paradigms. For instance, the “EyeCane”, a palm-size cane, which encodes distance and depth accurately and efficiently. We provide preliminary evidence that, following rehabilitation-oriented training, these SSDs can be used as stand-alone devices. This wide range of SSD applications will enable us to probe the task-specificity of the involved brain structures. To achieve this, our SSDs will be used in conjunction with cutting-edge neuroimaging and neurodisruptive techniques. We will chart the dynamics of the plastic changes in the brain by performing unprecedented longitudinal studies while individuals learn to use SSDs. This will allow us to probe the theory of brain areas as flexible sensory-modality-independent task-specific entities and promote our understanding of sensory integration and large scale brain plasticity.

Finally, these devices may be used together with the most advanced visual prostheses (“bionic eyes”) currently in the market, which at present lack in terms of resolution and in rehabilitative power. The SSDs may be used in training the brain to “see” prior to surgery, and in augmenting the capabilities of the “bionic-eyes” using information arriving from the same image (e.g. adding color, depth and, most critically, increased resolution) to create a unique and novel entity: an SSD-bionic eye hybrid. Our proposed research will lead to major advances in the understanding of brain functionality, adaptation following neural injury and changes taking place in the process of rehabilitation. We will continue to put these findings to functional use as we develop a suite of SSDs specifically tailored for the rehabilitative needs of the visually impaired.