People With Dyslexia Have Difficulty Not Just Reading Words, But Recognizing Voices

While most people think of dyslexia as primarily a problem with reading, people with dyslexia seem to have trouble processing the spoken language, as well. A new study published last week Science found that people with dyslexia have a harder time recognizing voices than other people do.
How the Heck:

• Participants in the study–half of whom were dyslexic–watched and listened to cartoon characters on a computer. Each character had a distinct voice, and spoke either English, the participants’ native language, or Mandarin Chinese.
• The participants were then played a clip of each voice and asked to match it to the correct character.
• People without reading difficulties were better at recognizing voices speaking their native language. They could correctly pick out which character went with a voice about two-thirds of the time if the voice was speaking English, and only about half the time if it was speaking Mandarin.
• Dyslexics, on the other hand, showed no native language boost. It didn’t matter if a voice was speaking English or Mandarin: they correctly matched it with a character around half the time either way.

What’s the Context:

• Researchers are increasingly finding that reading problems, while the most well known feature of dyslexia, are just a part of what’s going on. People with dyslexia have difficulty in processing and combining the sounds of language—and, when reading, correctly linking them to letters on a page.
• This study underscores the idea that people with dyslexia have trouble processing phonemes, the units of sound that make up speech—and that differ slightly between different voices, helping us to recognize who’s talking.

The Future Holds:

• Understanding the mental roots of dyslexia could help researchers develop early interventions, helping children who have trouble processing language even before they start school.
• Since children start to recognize voices long before they learn to read, some variation on a voice-recognition test could help identify children who might develop dyslexia.

Reference: Tyler K. Perrachione, Stephanie N. Del Tufo, & John D. E. Gabrieli. “Human Voice Recognition Depends on Language Ability.” Science, July 29, 2011. DOI: 10.1126/science.1207327