Non-speech and speech pitch perception among Cantonese-speaking children with autism spectrum disorder: An ERP study

The present study compared how Cantonese-speaking children with Autism Spectrum Disorder (ASD) and their typically developing counterparts perceived speech pitch and non-speech pitch information using ERP measurements. Sixteen children with ASD (mean age = 10.42 years, SD = 2.12 years) and sixteen normal controls (mean age = 9.48 years, SD =.86 years) participated in two experiments, in which Cantonese lexical tone contrasts and non-speech pitch variations were presented to children following an oddball paradigm when they watched a silent movie. The results showed that: 1) When processing speech pitch contour, the two groups did not differ in the amplitude of mismatch response (p-MMR), while typically developing controls showed larger mismatch negativity (MMN) responses than children with ASD. In the processing of speech pitch height, more positive p-MMR was observed among children with ASD than among normal controls and stronger MMN was found for typically developing children than for children with ASD. 2) For the processing of non-speech pitch, MMN rather than p-MMR was observed and the two groups did not differ significantly with each other in the amplitudes of MMN. These results indicated that Cantonese-speaking children with ASD manifested impaired ability when processing speech pitch information (i.e., lexical tone), which was in line with previous research. However, they did not show the advantage in processing non-speech or auditory pitch information, which was not in agreement with the previous studies. Results were discussed from the perspective of how language background (i.e., Cantonese) might shape the perceptive abilities of children.