The timing of syllable repetitions in developmental dyslexia.

The temporal organization of motor speech was examined in dyslexic adolescents and adults without overt speech difficulties, matched normal readers, and learning disabled adolescents without reading difficulties. Subjects were asked to repeat nonsense two- and three-syllable strings in time to each of four metronome speeds. Speech samples were analyzed for repetition rates, time coherence between prescribed and actual performance, and serial ordering of three-syllable strings. Dyslexic subjects deviated more from the prescribed rate, repeated syllables too slowly at all metronome speeds, and made more speech sequencing errors than normal or learning disabled controls. Repetition rate and syllable sequencing contributed as independent variables to the temporal organization of motor speech. The relevance of motor speech deficits for reading impairment in dyslexia is discussed.