Voice recognition involves perceiving differences in the way people speak. Individuals with dyslexia, however, cannot do this. The problem is a slight auditory impairment. They can understand perfectly well what others are saying and who is speaking. They’re just not as sensitive to subtle phonic variations between speakers.
A study by Tyler Perrachione at MIT [link] reaffirms the theory that the underlying deficit in dyslexia is about processing the sound of what’s written, not about seeing what’s written. They took it a step further and discovered a link between reading difficulty and the social ecology surrounding spoken language. Individuals with dyslexia have difficulty hearing consistent properties of speech within speaker as well as differences between speakers. “Lots of research has shown that individuals with dyslexia have more trouble understanding speech when there is noise in the background” says Perrachione. “These results suggest that part of the problem may be trouble following a specific voice.”
They took it another step further and found something that I find interesting. Individuals without dyslexia have the same difficulty hearing phonic variation between speakers in their second language (Mandarin Chinese) as dyslexics do between speakers in their native language. This corroborates my observation that children, without dyslexia, often perform at the same level as children with dyslexia when they are being taught to read for the first time in a foreign language. They don’t have the ‘phonic background’ necessary to identify the phonetic compounds of words. I believe this puts children from non-English backgrounds at a disadvantage when learning to read in English-speaking schools [link].