Sensitivity to structure in the speech signal by children with speech sound disorder and reading disability

Abstract

Purpose Children with speech sound disorder (SSD) and reading disability (RD) have poor phonological awareness, a problem believed to arise largely from deficits in processing the sensory information in speech, specifically individual acoustic cues. However, such cues are details of acoustic structure. Recent theories suggest that listeners also need to be able to integrate those details to perceive linguistically relevant form. This study examined abilities of children with SSD, RD, and SSD+RD not only to process acoustic cues but also to recover linguistically relevant form from the speech signal. Method Ten- to 11-year-olds with SSD (n = 17), RD (n = 16), SSD+RD (n = 17), and Controls (n = 16) were tested to examine their sensitivity to (1) voice onset times (VOT); (2) spectral structure in fricative-vowel syllables; and (3) vocoded sentences. Results Children in all groups performed similarly with VOT stimuli, but children with disorders showed delays on other tasks, although the specifics of their performance varied. Conclusion Children with poor phonemic awareness not only lack sensitivity to acoustic details, but are also less able to recover linguistically relevant forms. This is contrary to one of the main current theories of the relation between spoken and written language development.

Neural encoding of the speech envelope by children with developmental dyslexia

“…Arcs blew their cough ). Semantically unpredictable sentences were used to eliminate the use of compensatory contextual cues to identify the target words (Johnson et al, 2011). Participants received training with 4 sentences, each heard twice consecutively, first in the natural form and then in vocoded form.…”

“…This was our approach in the current study. We administered a word report task using noise vocoded speech that had been developed for children (Johnson, Pennington, Lowenstein, & Nittrouer, 2011), while simultaneously recording EEG. Noise vocoding degrades the temporal fine structure (TFS) of speech (see Fig.…”

Developmental dyslexia

“…Identifying syllables in speech is important early in development and various results suggest dyslexic children have trouble recovering syllables from the speech stream. For instance, recent studies have found dyslexic children have problems using an amplitude envelope to recover spoken words 47 and integrating various cues in word perception 48 . In the amplitude envelope (AE) task, a speech signal is filtered to remove brief acoustic cues that have traditionally been viewed as necessary for speech perception, especially the speech segmental cues that distinguish phonemes.…”

Perceptual weighting strategies of children with cochlear implants and normal hearing

“…Therefore it may be concluded that advantages seem to accrue to spoken language processes from the perceptual weighting strategies observed for mature language users listening to their native language. Developmentally, it has been observed that increasing sensitivity to word-internal phonemic structure (measured with phonemic awareness tasks) correlates with developmental shifts in perceptual weighting strategies (Boada & Pennington, 2006; Johnson, Pennington, Lowenstein, & Nittrouer, 2011; Nittrouer & Burton, 2005). Overall, then, acquisition of the perceptual weighting strategies typical among mature native speakers of a language has demonstrable, positive effects.…”