Judith Rispens

Non-Word Repetition in Dutch Children with (a Risk of) Dyslexia and SLI.

It has been proposed that poor non‐word repetition is a marker of specific language impairment (SLI), and a precursor and marker of dyslexia. This study investigated whether a non‐word repetition deficit underlies both disorders. A group of Dutch preschool SLI children and children at familial risk of dyslexia, as well as school‐going groups of SLI and dyslexic children were presented with a non‐word repetition task. The results showed that the SLI and the (at‐risk of) dyslexia groups performed more poorly than the control children. Furthermore, with the exception of one child, all preschool SLI children scored significantly below the mean of the preschool control group, suggesting that non‐word repetition performance is a marker of SLI. Approximately half of the at‐risk group were poor performers, which was expected on the basis of the familial risk factor of the at‐risk group. The results show that a non‐word repetition deficit is attested early in life and underlies both dyslexia and SLI.

Assessing comprehension and production of verbs and sentences: The Verb and Sentence Test (VAST)

Background : In this paper we present a new aphasia test for the asessment of comprehension and production of verbs and sentences, the Verb and Sentence Test (VAST). A description is given of selected theories underlying the construction of the test, the diagnostic properties, and how results from the test can be used to motivate therapy. Methods & Procedures : Information about the construction and standardisation of the VAST is provided. Justification for item selection and results obtained from 80 non-aphasic and 25 aphasic subjects are described. Details are given of the discriminative power of each task, and validity and reliability are discussed. Results : Data from the subjects demonstrate that the VAST effectively discriminates between the aphasic and non-aphasic population and between different types of verb and sentence deficits. Case studies are given to illustrate these points. Conclusions : The VAST provides a reliable research and clinical tool for the assessment of comprehension and production of verbs and sentences, and gives clear directions for treatment.

Subject–verb agreement and phonological processing in developmental dyslexia and specific language impairment (SLI): a closer look

BACKGROUND Problems with subject-verb agreement and phonological (processing) skills have been reported to occur in children with specific language impairment (SLI) and in those with developmental dyslexia, but only a few studies have compared such problems in these two groups. Previous studies have claimed a causal relationship between phonological processing deficits and morphosyntactic problems. AIMS The following questions were addressed in this study: (1) Are children with developmental dyslexia and SLI comparable in the level of sensitivity to subject-verb agreement, phonological awareness, and non-word repetition? (2) Are children with developmental dyslexia and SLI comparable in their performance profiles on tasks tapping subject-verb agreement, phonological awareness, and non-word repetition? (3) Are deficits in phonological processing skills related to morphosyntactic deficits? METHODS & PROCEDURES Forty-five children (mean age = 8;6 years) with developmental dyslexia, SLI and typically developing children participated. The sensitivity to subject-verb agreement, phonological awareness, and non-word repetition was measured. OUTCOMES & RESULTS Both the children with dyslexia and with SLI made more errors than the control children on the subject-verb agreement task, with the children with dyslexia scoring significantly better than the children with SLI. Similarly, the children with SLI and dyslexia both performed more poorly on the phoneme-deletion task than the control group. Both clinical groups performed more poorly on the non-word repetition task than the control children, with the children with dyslexia outperforming the children with SLI. In all three tasks differences in performance profiles were found between the children with developmental dyslexia and SLI. Across all three groups non-word repetition was correlated with morphosyntactic sensitivity. CONCLUSIONS The results show similarities between the performances of children with SLI and dyslexia on tasks tapping subject-verb agreement, phonological awareness, and non-word repetition: they scored more poorly than typically developing children. Qualitative analyses revealed, however, differences in the error patterns on all three tasks. Associations between non-word repetition and sensitivity to subject-verb agreement were found, suggesting that problems with phonological processing impact on morphosyntactic skills.

Non-word repetition in Dutch-speaking children with specific language impairment with and without reading problems

Recently, English studies have shown a relationship between non-word repetition (NWR) and the presence of reading problems (RP). Children with specific language impairment (SLI) but without RP performed similarly to their typically developing (TD) peers, whereas children with SLI and RP performed significantly worse on an NWR task. The current study was undertaken to investigate whether this difference in NWR performance is also found in a language with a transparent orthography--Dutch. The study included 15 TD children and 29 children with SLI. All children performed an NWR task that included non-words of 2-5 syllables in length. Children with SLI - RP (N = 11) did not differ on any of the four conditions from the TD group, whereas the children with SLI + RP (N = 18) scored more poorly on the 3-, 4-, and 5-syllable items compared to the TD group. NWR performance was significantly poorer on the 3- and 4-syllable conditions for children with SLI + RP compared to SLI - RP. To conclude, NWR is specifically affected in children with SLI + RP who are learning to read and write in a transparent orthography. Our data underline the dependency relation between literacy development and NWR performance in children with SLI.

Past tense productivity in Dutch children with and without SLI: the role of morphophonology and frequency

This study focuses on morphophonology and frequency in past tense production. It was assessed whether Dutch five- and seven-year-old typically developing (TD) children and eight-year-old children with specific language impairment (SLI) produce the correct allomorph in regular, irregular, and novel past tense formation. Type frequency of the allomorph, token frequency and phonotactic probability (PP) of the novel verb form are considered. The results showed all groups were sensitive to the phonological cue. PP did not contribute to past tense inflection of novel verbs in any of the groups, but type frequency did in all three groups. Only the seven-year-old typically developing children relied on token frequency for inflection of regulars. The findings point to an important role of phonology and frequency in past tense acquisition for both TD children and children with SLI. We discuss how the SLI performance pattern relates to theories on SLI.

Subject-verb agreement and phonological processing in developmental dyslexia and SLI: A closer look

BACKGROUND Problems with subject-verb agreement and phonological (processing) skills have been reported to occur in children with specific language impairment (SLI) and in those with developmental dyslexia, but only a few studies have compared such problems in these two groups. Previous studies have claimed a causal relationship between phonological processing deficits and morphosyntactic problems. AIMS The following questions were addressed in this study: (1) Are children with developmental dyslexia and SLI comparable in the level of sensitivity to subject-verb agreement, phonological awareness, and non-word repetition? (2) Are children with developmental dyslexia and SLI comparable in their performance profiles on tasks tapping subject-verb agreement, phonological awareness, and non-word repetition? (3) Are deficits in phonological processing skills related to morphosyntactic deficits? METHODS & PROCEDURES Forty-five children (mean age = 8;6 years) with developmental dyslexia, SLI and typically developing children participated. The sensitivity to subject-verb agreement, phonological awareness, and non-word repetition was measured. OUTCOMES & RESULTS Both the children with dyslexia and with SLI made more errors than the control children on the subject-verb agreement task, with the children with dyslexia scoring significantly better than the children with SLI. Similarly, the children with SLI and dyslexia both performed more poorly on the phoneme-deletion task than the control group. Both clinical groups performed more poorly on the non-word repetition task than the control children, with the children with dyslexia outperforming the children with SLI. In all three tasks differences in performance profiles were found between the children with developmental dyslexia and SLI. Across all three groups non-word repetition was correlated with morphosyntactic sensitivity. CONCLUSIONS The results show similarities between the performances of children with SLI and dyslexia on tasks tapping subject-verb agreement, phonological awareness, and non-word repetition: they scored more poorly than typically developing children. Qualitative analyses revealed, however, differences in the error patterns on all three tasks. Associations between non-word repetition and sensitivity to subject-verb agreement were found, suggesting that problems with phonological processing impact on morphosyntactic skills.

Negation in agrammatism: a cross-linguistic comparison

Abstract Negation is a concept that has hardly received attention in aphasia research. The present study describes the performance of agrammatic speakers of three different languages — English, Dutch and Norwegian — on a sentence comprehension and two sentence anagram tests. These languages have been chosen, because the structure of the negative sentence is different in terms of the internal structure of the negation phrase (NegP) and the position of this phrase in the syntactic tree. No difference in comprehension of negative and affirmative sentences is found. The results on the sentence construction tests, however, vary per language. The English agrammatics are worse than the Dutch and Norwegian in constructing negative, but not in positive sentences. It is suggested that it is the internal structure of NegP that influences agrammatic performance on a sentence construction task.

Word Recognition and Nonword Repetition in Children With Language Disorders: The Effects of Neighborhood Density, Lexical Frequency, and Phonotactic Probability

PURPOSE The effects of neighborhood density (ND) and lexical frequency on word recognition and the effects of phonotactic probability (PP) on nonword repetition (NWR) were examined to gain insight into processing at the lexical and sublexical levels in typically developing (TD) children and children with developmental language problems. METHOD Tasks measuring NWR and word recognition were administered to 5 groups of children: 2 groups of TD children (5 and 8 years old), children with specific language impairment (SLI), children with reading impairment (RI), and children with SLI+RI (all 7-8 years old). RESULTS High ND had a negative effect on word recognition in the older TD children and in the children with RI only. There was no ND effect in the younger children or in the children with SLI, who all had lower receptive vocabulary scores than the age-matched TD children and the RI groups. For all groups, NWR items with low PP were more difficult to repeat than items with high PP. This effect was especially pronounced in children with RI. CONCLUSION Both the stage of vocabulary development and the type of language impairment (SLI or RI) impact the way ND and PP affect word recognition and NWR.

Bilingual children's production of regular and irregular past tense morphology

This study examined the production of the Dutch past tense in Dutch-Hebrew bilingual children and investigated the effect of type of past tense allomorph (de versus te) and token frequency on productions of the past tense. Seven-year-old bilingual children (n=11) were compared with monolingual children: age-matched (n=30) and younger vocabulary-matched (n=21). Accuracy of regular and novel past tense was similar for the bilingual and monolingual groups, but the former group was worse on irregular past tense than the age-matched monolingual peers. All three groups showed effects of type frequency: te past tenses were more accurate than de. The difference between the bilingual and monolingual children surfaces in the extent of the effect: for the bilingual children it was most pronounced in verbs with low token frequency and novel verbs. Results are interpreted as stemming from a learning strategy or from phonological transfer from the Hebrew morphosyntactic system.

Visual artificial grammar learning in dyslexia : A meta-analysis

BACKGROUND Literacy impairments in dyslexia have been hypothesized to be (partly) due to an implicit learning deficit. However, studies of implicit visual artificial grammar learning (AGL) have often yielded null results. AIMS The aim of this study is to weigh the evidence collected thus far by performing a meta-analysis of studies on implicit visual AGL in dyslexia. METHODS AND PROCEDURES Thirteen studies were selected through a systematic literature search, representing data from 255 participants with dyslexia and 292 control participants (mean age range: 8.5-36.8 years old). RESULTS If the 13 selected studies constitute a random sample, individuals with dyslexia perform worse on average than non-dyslexic individuals (average weighted effect size=0.46, 95% CI [0.14 … 0.77], p=0.008), with a larger effect in children than in adults (p=0.041; average weighted effect sizes 0.71 [sig.] versus 0.16 [non-sig.]). However, the presence of a publication bias indicates the existence of missing studies that may well null the effect. CONCLUSIONS AND IMPLICATIONS While the studies under investigation demonstrate that implicit visual AGL is impaired in dyslexia (more so in children than in adults, if in adults at all), the detected publication bias suggests that the effect might in fact be zero.