March 11, 2014
Colors And Shapes Can Be Heard By The Blind: Study
[ Watch the Video: EyeMusic Live Demo at AIPAC ]
April Flowers for redOrbit.com - Your Universe OnlineNormally, people perceive colors and shapes visually, but what if you could "hear" them? A new study from Hebrew University shows that using sensory substitution devices (SSDs), colors and shapes can now be conveyed to the brain noninvasively through other senses.
Prof. Amir Amedi, of the Edmond and Lily Safra Center for Brain Sciences and the Institute for Medical Research Israel-Canada at the Hebrew University of Jerusalem Faculty of Medicine, leads the study at the Center for Human Perception and Cognition, which is offering tools to the blind and visually impaired via training with SSDs to receive environmental visual information and interact with it in ways otherwise unimaginable.
Yissum, the Hebrew University's Technology Transfer Company, has patented the work of Prof. Amedi and his team.
Using their existing senses, SSDs are non-invasive sensory aids that provide visual information to the blind. One example of an SSD would be a miniature camera connected to a small computer (or smart phone) and stereo headphones, which the user would wear. Using a predictable algorithm, the images are converted into a "soundscape" that allows the users to listen to and then interpret the visual information obtained by the camera.
EyeMusic SSD is an SSD available at the Apple App Store that plays pleasant musical notes to convey information about colors, shapes and locations of objects in the world around the user.
Combining the SSD equipment with a unique training program allows the blind to achieve various complex, visual-linked abilities. Recent studies published in Restorative Neurology and Neuroscience and Scientific Reports used EyeMusic SSD with blind and blindfolded-sighted users. The users were shown to correctly perceive and interact with objects, such as recognizing different shapes and colors or reaching for a beverage.
EyeMusic was also used to show that other fast and accurate movements can be guided by the EyeMusic tool and visuo-motor learning. The team published two studies in Neuron and Current Biology, demonstrating that the blind can characterize sound-conveyed images into complex object categories—for example, faces, houses and outdoor scenes, plus everyday objects. The participants were also able to locate people's positions, identify facial expressions and read letters and words.
SSDs are not widely used in the blind community, despite these encouraging behavioral demonstrations. The reasons that have prevented their adoption, however, have changed for the better over the past few years, according to an article published in Neuroscience & Biobehavioral Reviews. Due to technological advances, SSDs are much cheaper, smaller and lighter. They are also able to run on a standard smartphone. Training and performance have also been enhanced by new computerized training methods and environments.
Contrary to the widely-held conception of the cortex being divided into separate vision-processing areas, auditory areas, etc., the Hebrew University research has demonstrated that over the last decade, new findings have shown that many brain areas are characterized by their computational task, and can be activated using senses other than the one commonly used for this task, even for people who were never exposed to "original" sensory information at all—for example, a person born blind that never saw one photon of light during his lifetime.
The research team showed that when users process "visual information" through the SSD, congenitally blind people who learned to read by touch using the Braille script or through their ears with sensory substitution devices use the same areas in the visual cortex as those used by sighted readers. An example of this technique, recently published in Current Biology, revealed that blind subjects use SSD equipment and training to "see" body shapes.
An entire network of regions in the human brain are dedicated to processing and perception of body shapes. This network starts in the areas processing vision in the cortex, leading to the "Extrastriate Body Area" (EBA), and further connecting to multiple brain areas deciphering people's motion in space, their feelings and intents.
The EBA in the blind was found to be functionally connected to the whole network of body-processing found in the sighted. This finding bolsters the researchers' new theory of the brain as a sensory-independent task machine instead of a pure sensory machine based on vision, audition or touch.
"The human brain is more flexible than we thought," says Prof. Amedi. "These results give a lot of hope for the successful regaining of visual functions using cheap non-invasive SSDs or other invasive sight restoration approaches. They suggest that in the blind, brain areas have the potential to be 'awakened' to processing visual properties and tasks even after years or maybe even lifelong blindness, if the proper technologies and training approaches are used."