An innovative development could effectively enable blind people to 'see', which could potentially transform the way in which written text is absorbed by those with vision loss.
The method has been developed by experts at the Hebrew University of Jerusalem and is designed to help train blind people to "see" through the use of a sensory substitution device (SSD). They can then "read" an eye chart with letter sizes smaller than those used in determining the international standard for blindness.
The study carried out at the facility involved eight congenitally blind participants, who are able to pass the conventional eye-exam of the Snellen acuity test, which surpasses the World Health Organization's criteria for blindness and moved them to the level of low-vision sighted.
In the report, published in the PLoS One Journal, the experts explain how the participants, by using the SSD, reached a median vision level of 20/360, which means they could identify letters from a distance of 20 feet that a normally sighted person would be able to identify from 360 feet.
This is better than the World Health Organization criterion for blindness, which is currently 20/400.
The SSD, known as The vOICe, was developed by Dr Peter Meijer and works by converting images from a miniature camera into soundscapes, using a predictable algorithm.
As a result, the user is able to listen to and then interpret the visual information coming from the camera.
Proficient users of the SSD who had dedicated training at the laboratory of lead researcher Dr Amir Amedi were able to use SSDs to identify complex everyday objects, locate people and their postures, read letters and words, and even identify facial expressions.
The experts note that SSDs could be an attractive alternative to the invasiveness and high cost of retinal prostheses and also offer hope to the 39 million worldwide blind population, the majority of whom live in developing countries.