Cortical tracking of natural speech by children with developmental language disorder (DLD): An EEG speech decoding...

Area of Science:

• Neuroscience
• Developmental Psychology
• Speech and Hearing Sciences

Background:

• The Temporal Sampling (TS) theory links developmental language disorder (DLD) to sensory and linguistic rhythm processing deficits.
• These deficits include reduced sensitivity to amplitude rise times (ARTs) and speech rhythm, impacting automatic cortical speech tracking.

Purpose of the Study:

• To investigate neural Temporal Sampling (TS) theory predictions in children with DLD.
• To measure low-frequency cortical tracking accuracy in natural continuous speech using EEG in children with and without DLD.

Main Methods:

• Recorded EEG during story listening from 9-year-old children with and without DLD.
• Performed decoding analyses in delta, theta, and alpha bands.
• Computed EEG power in delta, theta, and gamma bands, and phase-amplitude/phase-phase coupling (PAC, PPC) between bands.

Main Results:

• Whole-brain analyses showed no significant difference in low-frequency decoding (delta, theta) accuracy between groups.
• Region-specific analyses revealed significantly reduced delta-band speech tracking in the right temporal cortex of children with DLD.
• Phase-amplitude coupling (PAC) and phase-phase coupling (PPC) dynamics did not differ between groups.

Conclusions:

• Low-frequency cortical tracking impairments in DLD may be spatially constrained to the right hemisphere.
• This contrasts with global impairments observed in developmental dyslexia (DD).
• Findings support a spatially specific neural basis for DLD according to TS theory.