Atypical speech production of multisyllabic words and phrases by children with developmental dyslexia

Abstract

Cross-language data show that children with dyslexia are poor at recognizing syllable stress patterns, yet their speech production appears normal, suggesting an unexpected disconnect between speech input and output processes. Here we utilized a novel computerized speech copying task based on the speech amplitude envelope (AE) to investigate this disconnect. Seventy-five children with and without dyslexia copied familiar spoken targets like "Aladdin". Children with dyslexia were significantly worse at producing the multi-syllabic targets as indexed by two similarity metrics for computing the AE. They did not differ from other children in producing the pitch contours of items. Accordingly, impaired AE perception in dyslexia is matched by impaired AE production. Children with dyslexia are heard to produce multi-syllabic words normally because their pitch contours are intact.

Infant low-frequency EEG cortical power, cortical tracking and phase-amplitude coupling predicts language a year later.

“…LFP centre frequencies were filtered from 2 to 8 Hz, in 1 Hz steps with a 2 Hz bandwidth, and HFA centre frequencies were filtered from 17.5 Hz to 42.5 Hz, in 5 Hz steps with a 5 Hz bandwidth before a normalised modulation index value was computed for each channel (19,42). The EEG bands were defined as delta (2-4 Hz), theta (4-8 Hz) beta (15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30) and gamma (30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45). The channel exhibiting the strongest nMI, within predefined phase and amplitude band groupings (delta/beta, delta/gamma, theta/beta, theta/gamma), was taken forward for further analysis.…”

“…Based on (32), we can expect that individual differences in the theta/delta power ratio for infants may also predict subsequent language development. Furthermore, previous electrophysiological and magnetoencephalography studies testing TS theory with children with dyslexia have revealed a significant role for delta band encoding in both phonological and vocabulary development (33–36). Filtered speech interventions that enhance delta-band information also improve the theta-delta oscillatory power ratio during speech listening for dyslexic children (34).…”

“…In brief, if low-frequency cortical tracking and/or dynamic relations between frequency bands are atypical, then developmental trajectories for language may also be atypical. Previous electrophysiological studies testing TS theory with children have revealed a significant role for delta band encoding in both phonological and vocabulary development (30–33). However, PAC (delta-beta PAC) was not significantly different in children with dyslexia in a language processing (sentence repetition) task (32).…”

Atypical speech production of multisyllabic items by children with developmental language disorder (DLD) indicate prosodic difficulties

“…The current study fills this gap regarding TS theory. It is based on a methodology first developed by Keshavarzi et al (2023) to study speech production in developmental dyslexia.…”

Abnormal brain activation patterns during speech perception and production in children and adults with reading disability

“…Phonological deficits could be reflected in both speech perception and production in early life (Gerrits & de Bree, 2009;Keshavarzi et al, 2022); however, relatively fewer studies have concerned speech production in RD, presumably because it is challenging to collect evidence in infants/young children for speech production. An alternative is to examine foreign speech perception and production in older children and adults with RD, and to test whether brain activity patterns during these tasks can be reliable markers of RD, which would also facilitate diagnosis of RD.…”