台大心理系

Converging evidence across language and reading acquisition studies suggests that children’s sensitivity to rhythmic modulations within the linguistic stream is critical for both language and reading acquisition (Goswami, 2011; Petitto, 2001). The study offers an investigation into the sensory bases of “language” related auditory perception in children. We hypothesized that across languages, children with developmental dyslexia have a specific difficulty with the neural representation of the phonological structure of speech. We compared matched samples of children with and without dyslexia learning three very different spoken and written languages, e.g. English, Spanish and Chinese. The key sensory cue measured was rate of onset of the sound amplitude envelope, known to be critical for the rhythmic timing of speech (prosody). Despite phonological and orthographic differences, for each language, rise time sensitivity was a significant predictor of phonological awareness and rise time was the only consistent predictor of reading acquisition. The data support the hypothesis that the brain’s sensitivity to slow rhythmic modulation helps the child extract and process critical linguistic information (e.g., syllables and words). These findings carry implications for identifying children at risk for reading impairments.