Auditory Language Comprehension in Children with Developmental Dyslexia: Evidence from Event-related Brain Potentials

Abstract

Abstract& In the present study, event-related brain potentials (ERPs) were used to compare auditory sentence comprehension in 16 children with developmental dyslexia (age 9-12 years) and unimpaired controls matched on age, sex, and nonverbal intelligence. Passive sentences were presented, which were either correct or contained a syntactic violation (phrase structure) or a semantic violation (selectional restriction). In an overall sentence correctness judgment task, both control and dyslexic children performed well. In the ERPs, control children and dyslexic children demonstrated a similar N400 component for the semantic violation. For the syntactic violation, control children demonstrated a combined pattern, consisting of an early starting bilaterally distributed anterior negativity and a late centro-parietal positivity (P600). Dyslexic children showed a different pattern that is characterized by a delayed left lateralized anterior negativity, followed by a P600. These data indicate that dyslexic children do not differ from unimpaired controls with respect to semantic integration processes (N400) or controlled processes of syntactic reanalyses (P600) during auditory sentence comprehension. However, early and presumably highly automatic processes of phrase structure building reflected in the anterior negativity are delayed in dyslexic children. Moreover, the differences in hemispheric distribution of the syntactic negativity indicate different underlying processes in dyslexic children and controls. The bilateral distribution in controls suggests an involvement of right hemispherically established prosodic processes in addition to the left hemispherically localized syntactic processes, supporting the view that prosodic information may be used to facilitate syntactic processing during normal comprehension. The left hemispheric distribution observed for dyslexic children, in contrast, suggests that these children do not rely on information about the prosodic contour during auditory sentence comprehension as much as controls do. This finding points toward a phonological impairment in dyslexic children that might hamper the development of syntactic processes. &

Impaired semantic processing during sentence reading in children with dyslexia: Combined fMRI and ERP evidence

“…This suggests that the reduction of the N400-effect in dyslexic participants also develops with age, thus paralleling the effect found in the inferior parietal area for sentence reading (Meyler et al, 2007). Reduced N400 effects during sentence processing in dyslexia seems to be limited to reading tasks, as no difference in the N400 effect between dyslexic and control children at a similar age were found with sentences presented in the auditory modality (Sabisch et al, 2006).…”

“…The late positive effect after 600 ms presumably corresponds to the P600 effect that has been associated with congruency judgement during sentence processing (Kolk et al, 2003;Sabisch et al, 2006). Processing related to congruency judgement can be expected to occur in the present experiment also for sentences to which children do not respond, because the rare response prompts occurred only some time after a sentence was presented.…”

Semantic, syntactic, and phonological processing of written words in adult developmental dyslexic readers: an event-related brain potential study

“…As in the aforementioned studies of Leikin and coworkers, the P600 was changed in dyslexics, but only for some forms of grammatical violations. A recent study by Sabisch and co-workers [70] presented phrase structure violations in passive sentences to dyslexic children and controls. While control children showed an early starting bilaterally distributed anterior negativity and a late centro-parietal positivity (P600), dyslexics ERPs were characterized by a delayed left lateralized anterior negativity, followed by a P600.…”

“…To the extent that these difficulties might propagate to later processing stages (see, for example, [70]), a delay in the ERP effects to gender and semantic violations was also expected.…”

Neurobiological Approaches on Brains of Children with Dyslexia

“…Sabisch et al (73) used ERPs to compare auditory sentence comprehension in 16 children with dyslexia (age, 9-12 years) and unimpaired controls matched on age, sex, and nonverbal intelligence. The recruiters performed on passive sentences, which were either correct or contained a syntactic violation (phrase structure) or a semantic violation (selectional restriction).…”