Informational masking of complex tones in dyslexic children.
In complex auditory scenes, perceiving a given target signal is often complicated by the presence of competing maskers. In addition to energetic masking (EM), which arises because of peripheral interferences between target and maskers at the cochlear level, informational masking (IM), which takes place at a more central level, is also responsible for the difficulties encountered in typical ecological auditory environments. While recent research has led to mixed results regarding a potential speech-perception-in-noise deficit in dyslexic children, most of them actually investigated EM situations. The current study aimed at evaluating dyslexic children's sensitivity to pure IM in complex auditory sequences. Performance of the control normally-reading children increased throughout the experiment, reaching a significantly better level than dyslexics' in the last blocks. Our results provide evidence for a general auditory deficit in noise in dyslexic children. Although due to central mechanisms, this deficit does not seem to stem from a mere auditory attention impairment. Further research is needed to examine the precise nature of the auditory difficulty, and its link with reading acquisition in dyslexic children.