Phonological deficit in school children is reflected in the Mismatch Negativity.

Deficits in processing of auditory stimuli are known to play an important role in the aetiology of dyslexia. To specify the auditory deficit in children at risk for dyslexia, 19 children with a phonological deficit and 15 controls were tested using the mismatch negativity event-related potential, which reflects preattentive auditory processing. Children with a phonological deficit, not yet suffering from dyslexia, had similar mismatch negativity patterns to dyslexics. The deficit was speech specific, because there were significant group differences only with syllables but not with pure tones.