People with dyslexia struggle to recognise familiar voices,scientists suggest.
The finding is the first tentative evidence that smallsounds in the human voice that vary between people are difficult for dyslexicsto hear.
Writing in the journal Science, the scientists say that manypeople could have some degree of "voice blindness". And by studyingit, scientists hope to better understand how the human brain has evolved torecognise speech. Humans rely on small sounds called phonemes to tell oneperson from another. As we first try to form the word dog, for example,phonemes are the "duh"-"og"-"guh" sounds that ourparents prompt us to make.
But as we master the ability to read, we become less relianton recognising these sounds to read, and eventually stop noticing them. Despiteignoring them, however, phonemes remain important for voice recognition. Thetiny inflections in the way people pronounce phonemes gives a listener cues totell one voice from another.
Because people who suffer from dyslexia are known tostruggle with phonemes when reading, a US-based team of scientists wonderedwhether they might also struggle hearing them in people's voices. Toinvestigate, the team grouped 30 people of similar age, education and IQ intotwo camps: those with and without a history of dyslexia.
The subjects then went through a training period to learn toassociate 10 different voices - half speaking English and half speaking Chinese- with 10 computer-generated avatars.