A new study by Cell Press finds that a specific abnormality in the processing of auditory signals accounts for the main behaviors of dyslexia.
Many with dyslexia have difficulty paying attention to individual speech sounds, a limited ability to repeat a list of pseudowords or numbers, and a slow performance when asked to name a series of pictures, colors, or numbers as quickly as possible. The researchers were curious about whether an abnormality in the early steps of auditory processing in the brain known as "sampling" is linked to these dyslexia symptoms. They believed that an anomaly in the initial processing of phonemes, the smallest unit of sound that can be used to make a word, might have a direct impact on the processing of speech.
Their results suggest that the left auditory cortex of dyslexics might be less responsive to modulations at very specific frequencies that are optimal for analysis of speech sounds and overly responsive to higher frequencies. This could be detrimental to their speech abilities and short-term memories.
To learn more about this fascinating study, visit EurekAlert.