Hebrew University professor Amir Amedi has used an augmented reality device to allow the blind to “see” by converting images to complex sounds. The user is able to form a mental image of objects, including people, in front of them.
The cerebral cortex is activated when sighted people see an outline of the human body. The extrastriate area responds more strongly to human body images than it does to other objects. Blindness stops the usual flow of information from the eyes to this part of the brain, and people who’ve been blind since birth have never seen a human form. Their brains must change as they they learn to perceive body shapes using sound.
Ella Striem-Amit and Amir Amedi scanned the brains of seven congenitally blind people who’d trained for an average of 73 hours on the augmented reality system. The surprising result was that the visual cortex was activated by the auditory stimuli. Participants classified three different types of objects: people, everyday objects, and textured patterns.
Professor Amedi’s lab does groundbreaking research on perception and multisensory relation, sensory substitution approaches and dynamics of brain processes. Among other innovations, they are now experimenting with an ultrasound stick that measures distances from objects, providing auditory indications.