Visual pathways and Neuroplasticity

The visual pathways

The neuronal network of the visual system spans from the eye to the back of the brain and continues to other locations within parietal, temporal and frontal lobes. This network allows us to interpret information, from visible light, to build a representation of our surrounding world.

Images from the outside world are projected through the eye, via the optic nerve, reaching the optic chiasm. At the optic chiasm visual information from the left hand side of the world, from both eyes, travels to the right hand side of the brain. Conversely, visual information from the right hand side of the world, from both eyes travels to the left hand side of the brain. Therefore neuronal networks representing the left and right hand side of the visual field are located on the contra lateral side of the brain.

Visual information enters an area of the back of the brain called the visual cortex. This information enters via multiple neuronal networks called optic radiations.

If part of the visual pathway is damaged, it is possible that multiple channels of visual processing still exist within the blind field area. It has been hypothesised that reconfiguration of these pathways, through a process called neuroplasticity, can lead to an improvement in visual sensitivity.

What is Neuroplasticity

It was originally thought that the brain was hardwired and therefore allowed no flexibility within the brain system, should circumstances change. There is now a wealth of evidence, mainly from animal studies, that supports the idea of neuroplasticity occuring within the brain. This would mean that the brain has the intrinsic property of reconfiguring and adapting. Enabling the brain to re wire or create new pathways to compensate for changes occurring post injury.  With this in mind it is therefore highly likely that through correct guidance, for example using a systematic rehabilitation program such as NeET, that changes in visual pathways can occur.

Currently there are few options available to patients with vision loss post stroke or other brain injury. Widely used interventions such as prisms or scanning techniques may help the patient cope with changes to their vision however they do not stimulate changes to occur within the visual system.

Neuro-Eye Therapy uses a medical device, the vision rehabilitation program, designed to help those who have suffered partial blindness as a result stroke or other brain injury. Click here for information on research papers published by the University of Aberdeen vision laboratory.