Slide Slam O2
Neural tracking of speech and song in children with and without dyslexia
Christina der Nederlanden1, Jessica Grahn1, Marc Joanisse1; 1Western University, The Brain and Mind Institute
A growing literature has examined neural phase-locking to speech rhythms in dyslexia, and suggests marked deficits in processing the slow syllable rhythms of speech. This rhythmic processing deficit in children with dyslexia is consistent with the view that reading difficulties are related to more basic problems in phonological processing. Of interest in the current study is whether these deficits also extend to other domains relying heavily on temporal processing, such as music. To address this, we examined how children with and without dyslexia neurally track the rhythms of natural spoken and sung utterances using EEG. Children completed reading, phonological processing, and musical beat processing tasks to understand the relationship between the neural processing of speech rhythms, musical rhythms, reading, and phonological awareness. We used the neural measure of cerebro-acoustic phase coherence (henceforth, neural tracking), which estimates how consistently individual’s neural activity aligns with the amplitude envelope of the spoken and sung stimuli. Forty-five 8- to 10-year-old children (18 poor readers) showed significant neural tracking of low-frequency (delta/theta) syllable information for both speech and song, but there was no difference between neural tracking for spoken and sung utterances. Poor readers showed significantly greater neural tracking than typically developing readers in a higher frequency band (beta: 12-20 Hz) corresponding to the phoneme rate in our stimuli. This increased neural tracking correlated significantly with the word reading efficiency scores (TOWRE) suggesting a relationship between abnormal neural processing and reading deficits across good and poor readers. There were no differences between the poor and typically developing readers when tracking the rhythms of song, suggesting that the musical structure of song may allow children with dyslexia to process speech in the same way as their typically developing peers. Further connections between musical beat processing, neural processing, and reading ability will be discussed.