Auditory scene analysis in dyslexics

It has been argued that dyslexics suffer from temporal sensory processing deficits which affect their ability to discriminate speech in quiet environments. The impact of auditory deficits on non-language aspects of perception, however, is poorly understood. In almost every natural- listening environment, one must constantly construct scenes of the auditory world by grouping and analyzing sounds generated by multiple sources. We investigated whether dyslexics have difficulties grouping sounds. The results demonstrate that dyslexics have an impairment in grouping auditory objects that depends both on the sounds' frequency and presentation rate (i.e. the spectro-temporal context of the sound). We conclude that dyslexics have difficulty constructing scenes of the auditory world, and that these deficits can contribute to learning impairments. (C) 2000 Lippincott Williams and Wilkins.