Georgetown University student Heather Doherty dives deep into sensory substitution studies.
Growing up with a blind grandmother, I’ve always felt particularly passionate about the rights of individuals with disabilities and advocating that they are just as capable as any other individual. Thus, learning about new prosthesis that allow blind users to ‘see’ through their ears is an exciting development that has potential to prove blindness does not take from competency.
For those born blind or who go blind early in life, like my grandmother, auditory plasticity can compensate for loss of vision. Auditory functions are able to expand into regions of the brain that typically would have visual functions (Rauschecker, 2014). Thus, the auditory system expands to take on functions that facilitate communication through other senses.
In fact, many studies have found blind people can use echos for spatial orientation, and even exercise facial vision for object recognition and obstacle avoidance. Some studies go as far as to say there is a type of sonar system in the blind.
“Blind people can develop auditory senses much more complex and advanced than sighted people. In this way, they can ‘see’ through their ears and fingertips through their heightened recognition of objects through echos and touch.”
Heather Doherty, Georgetown University student
This is all to say that blind people can develop auditory senses much more complex and advanced than sighted people. In this way, they can ‘see’ through their ears and fingertips through their heightened recognition of objects through echos and touch. Seeing my grandmother read signs in braille growing up was always confusing to me; when I tried to read braille, I was never able to decipher each symbol from another, yet it was so easy for my grandmother. This behavioral observation is similar to the auditory system’s relationship with blindness in that for those who go blind early, neural plasticity is important in reassigning visual functions to other senses. My grandmother’s loss of vision allowed for her heightened senses of touch and hearing.
Additionally, new prostheses are being developed based on the fact that the occipital cortex is activated by auditory input in the blind. These new prostheses can transform visual position into frequencies, allowing blind users to understand complex sound patterns similar to how sighted people understand visual scenes (Rauschecker, 2014). Users can even read with this new technology, by being able to identify letters through their unique frequencies.
This would be a game changer for people like my grandmother, who live alone and have to rely on others for assistance in non-accommodating situations. Though the blind are just as capable as sighted people in taking care of themselves, there are many aspects of life that are nearly impossible for blind people to participate in alone.
For example, my grandmother is unable to go grocery shopping without someone helping her read labels, nutrition facts, and signs. However, with this new technology, she would be able to read on her own and thus gain more independence and control over her life.
Technology in the past decade has already assisted so much in my grandmother’s life. Previously she was unable to read books alone, but the influx of accessibility to spoken book recordings through programs such as Audible has allowed her to read independently. Additionally, she is able to text through spoken-to-text technology, and read our responses by asking Siri to read them for her.
Research on auditory comprehension not only helps us better understand the functions of our brains, but also contributes to developing technology that improves quality of life for all individuals with disabilities. I look forward to seeing how new technology supports disabled individuals in their everyday life and fights to prove their competency.
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McCollum, Sean. (2019). Your Brain on Music: The Sound System Between Your Ears. The Kennedy Center. https://www.kennedy-center.org/education/resources-for-educators/classroom-resources/media-and-interactives/media/music/your-brain-on-music/your-brain-on-music/your-brain-on-music-the-sound-system-between-your-ears/
Rauschecker, Josef P. (2014). Functional plasticity in the central nervous system: Plasticity in auditory functions. In M. Seltzer et al., Textbook of Neural Repair and Rehabilitation 2e (pp. 125-139). Cambridge University Press.