Auditory language comprehension in children with developmental dyslexia: Evidence from event-related brain potentials

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

Evidenzbasierte Therapie von Sprachentwicklungsstörungen

Zur Behandlung von Kindern mit Sprachentwicklungsstörungen stehen zahlreiche Methoden zur Verfügung. Diese gehen von ganz unterschiedlichen Konzepten aus. Die klassische Sprachtherapie ist ein rein symptomatischer Behandlungsansatz. Der Spracherwerbsprozess wird durch eine Erhöhung und Verbesserung des Sprachangebots (Input-Therapie) sowie eine Anregung zum aktiven Sprachgebrauch (Output-Therapie) unterstützt. Dazu wurde eine große Zahl spezifischer Verfahren entwickelt. Kausale Therapieansätze gehen davon aus, dass auditive, oralmotorische oder andere basale Defizite dem gestörten Spracherwerb zugrunde liegen. Dementsprechend steht ein Training psychischer Basisfunktionen im Mittelpunkt. Alternative Behandlungsmethoden wiederum beruhen auf recht verschiedenen, bislang unzureichend belegten Grundannahmen und werden nicht nur für Sprachstörungen, sondern für alle Entwicklungsstörungen in gleicher Weise empfohlen. Im Vortrag wird ein Überblick über unterschiedliche Therapierichtungen gegeben und hinterfragt, welcher Nutzen für die Kinder von den einzelnen Behandlungsverfahren zu erwarten ist. Anhand der Ergebnisse einzelner Studien wird dargestellt, für welche Therapiemethoden Wirksamkeit (efficacy), Nützlichkeit (effectiveness) und/oder Wirtschaftlichkeit (efficiency) nachgewiesen wurden. Abschließend werden Merkmale zur Bewertung einer Therapie genannt, die eine Abgrenzung wirksamer und weniger wirksamer Methoden ermöglichen und damit eine sinnvolle Therapiegestaltung erleichtern

Maturation of the long-latency auditory ERP: step function changes at start and end of adolescence.

The auditory event-related potential (ERP) is obtained by averaging electrical impulses recorded from the scalp in response to repeated stimuli. Previous work has shown large differences between children, adolescents and adults in the late auditory ERP, raising the possibility that analysis of waveform shape might be useful as an index of brain maturity. We reanalysed auditory ERPs from samples previously described by Albrecht, von Suchodoletz and Uwer (2000) and Uwer, Albrecht and von Suchodoletz (2002), using the intraclass correlation (ICC) as a global measure of similarity of an individual's waveform to a grand average comparison waveform for each age band. Three developmental periods were clearly distinguished: 5 to 12 years, 13 to 16 years, and adulthood. However, within each of these periods, there was no evidence of any developmental progression with age

Lexical-semantic processes in children with specific language impairment

The current study used event-related brain potentials to investigate lexical-semantic processing of words in sentences spoken by children with specific language impairment and children with normal language development. Children heard correct sentences and sentences with a violation of the selectional restriction of the verb. Control children showed an N400 effect followed by a late positivity for the incorrect sentences. In contrast, children with specific language impairment showed no N400 effect but did show a late, broadly distributed positivity. This absence of the N400 effect is due to a relatively large negativity for correct sentences, suggesting weaker lexical-semantic representations of the verbs and their selectional restrictions in children with specific language impairment