From Cortical Blindness to Conscious Visual Perception: Theories on Neuronal Networks and Visual Training Strategies.
Frontiers in Systems Neuroscience January 1, 2017 DOI: 10.3389/fnsys.2017.00064 (opens in new tab) via PubMed
Summary
AI-generated from the abstractHomonymous hemianopia (HH), the most common cortical visual impairment causing blindness in half the visual field, disrupts daily activities like exploration and orientation. Patients can retain blindsight—unconscious perception of stimuli in the blind field. This article argues that type I and type II blindsight arise from an altered global workspace due to disrupted perception, attention, and conscious networks. To enable residual abilities to reach visual consciousness, rehabilitation should stimulate subcortical extrastriate pathways via V5/MT to enhance neural synchronization. Combining multisensory bottom-up compensation with top-down restitution training could engage existing and new neuronal mechanisms, potentially restoring functionality.
Study at a glance
| Characteristics | Theoretical or philosophical paper Peer reviewed |
|---|---|
| Keywords | Blindsight Cortical blindness Global workspace theory Hemianopia Multisensory training |
| Key finding | Proposes that multisensory bottom-up compensation combined with top-down restitution training could target pre-existing and new neuronal mechanisms to recreate a framework for potential functionality in homonymous hemianopia. |
Abstract
Homonymous hemianopia (HH) is the most common cortical visual impairment leading to blindness in the contralateral hemifield. It is associated with many inconveniences and daily restrictions such as exploration and visual orientation difficulties. However, patients with HH can preserve the remarkable ability to unconsciously perceive visual stimuli presented in their blindfield, a phenomenon known as blindsight. Unfortunately, the nature of this captivating residual ability is still misunderstood and the rehabilitation strategies in terms of visual training have been insufficiently exploited. This article discusses type I and type II blindsight in a neuronal framework of altered global workspace, resulting from inefficient perception, attention and conscious networks. To enhance synchronization and create global availability for residual abilities to reach visual consciousness, rehabilitation tools need to stimulate subcortical extrastriate pathways through V5/MT. Multisensory bottom-up compensation combined with top-down restitution training could target pre-existing and new neuronal mechanisms to recreate a framework for potential functionality.