Fritjof Norrelgen

Language and Communication Skills in Preschool Children with Autism Spectrum Disorders: Contribution of Cognition, Severity of Autism Symptoms, and Adaptive Functioning to the Variability.

This study examined the contribution of cognitive function, severity of autism, and adaptive functioning to the variability in language and communication skills in 129 preschool children (aged 24-63 months) with autism spectrum disorder (ASD). Participants were selected from a representative research cohort of 208 preschool children on the basis of caregiver completion of the MacArthur-Bates Communicative Development Inventories (CDI). The children were classified into three cognitive groups: (a) Normal intelligence; (b) Developmental delay; and (c) Intellectual disability. Autism symptom severity was measured by the Autistic Behavior Checklist (ABC), and adaptive functioning by the Daily Living Skills (DLS) and Socialization (Soc) subscales from the Vineland Adaptive Behavior Scales. For each of five CDI variables (Phrases understood, Words understood, Words produced, Gestures and actions, and Language use), the contribution of cognition, severity of autism symptoms, and adaptive functioning to the variability was examined. Cognition and age explained about half or more of the variance in the four verbal language CDI variables, but only about one fourth of the variance in the non-verbal communication variable Gestures and actions. Severity of autism symptoms and the two adaptive measures (DLS and Soc) each only accounted for a few percent more of the variance in the four CDI language variables; however, for Gestures and actions, an additional 11-21% of the variance was accounted for. In conclusion, for children with ASD, receptive and expressive language is mainly related to cognitive level, whereas non-verbal communication skills seem to also be related to severity of autism symptoms and adaptive functioning.

Phonological working memory with auditory presentation of pseudo-words -- an event related fMRI Study.

Phonological working memory (PWM) tasks consist of a sequence of stimulus-encoding, maintenance and response. Few previous functional magnetic resonance imaging (fMRI) studies of PWM have employed event-related designs that make it possible to analyze the activations associated with each phase of such a task. The exploration of the cortical activation that takes place during the maintenance of PWM has been of particular interest to us. It has been suggested that temporary storage is served by the inferior parietal cortex. However, to the best of our knowledge earlier studies have used visual stimuli that might generate different cortical activations than auditory stimuli, which, presumably, would be more dependent on the auditory association cortex in the temporal lobe. This study involved an auditory stimulus presentation and a forced two-choice task. We used a parametric event-related design with fMRI. The stimuli consisted of pseudo-words of five, seven and nine syllables in length. In the control task, acoustically analogous stimuli without phonetic or linguistic content were used for passive listening. The left inferior frontal gyrus was activated during the stimulus-encoding, maintenance and response, in agreement with previous studies. However, in contrast to previous studies using visual presentation of verbal material, the inferior parietal cortex was not activated during the maintenance in the present study, but only active in the comparison and decision phase. Significant activation of the auditory cortex in the middle temporal gyrus was observed during the maintenance phase, which, together with the inferior frontal gyrus activation might underly the maintenance of phonological information.

Coexisting Disorders and Problems in Preschool Children with Autism Spectrum Disorders

Objectives. To analyze cooccurring disorders and problems in a representative group of 198 preschool children with autism spectrum disorders (ASD) who had had interventions at a specialized habilitation center. Methods. Parents and children were seen by a research team. Data were based on parental interviews, pediatric assessments, and tests of the child. Information on autistic symptoms, general cognitive function, speech and language, motor function, epilepsy, vision, hearing, activity level, behavior, and sleep was collected. Results. Three ASD categories were used: (1) autistic disorder (AD), (2) autistic-like condition (ALC) or Asperger syndrome, and (3) one group with autistic symptoms/traits but not entirely all its criteria met for ASD. Children with autism had a mean of 3.2 coexisting disorders or problems, the ALC/Asperger group had a mean of 1.6, and children with autistic traits had a mean of 1.6. The most common disorder/problems in the total group pertained to language problems (78%), intellectual disability (ID) (49%), below average motor function (37%), and severe hyperactivity/ADHD (33%). Conclusions. The results accord with the concept of early symptomatic syndromes eliciting neurodevelopmental clinical examination (ESSENCE), and highlight the need of considering ASD in a broad perspective taking also other cooccurring developmental disorders into account.

Developmental profiles and auditory perception in 25 children attending special preschools for language‐impaired children

Aim: To study different developmental profiles and auditory perception in a representative group of children with language impairment (LI). Methods: A multidisciplinary investigation was carried out in a group of 25 children attending units specifically for language‐impaired children. An assessment of the cognitive level, motor performance, behaviour and auditory perception was performed and the results were compared with those for age‐matched groups of children. Results: Among those with moderate or severe language impairment (LI), around 90% had additional developmental disorders. In three tests of auditory perception, children with LI had problems with working memory and speech discrimination. No problems were found with the childrens temporal resolution in auditory perception. Another conclusion from the auditory perceptual tests was that the childrens cognitive abilities were important for their success in these tests.

Speech discrimination and phonological working memory in children with ADHD

This study examined phonological working memory and speech discrimination among children with attention‐deficit–hyperactivity disorder (ADHD) with and without motor problems. Forty‐one children were assigned to three groups; children with ADHD (N=9), children with ADHD plus developmental coordination disorder (ADHD+, N=13), and age‐matched control children (N=19). The subjects’ability to classify stimulus pairs was examined in two experiments. The first experiment required subjects to discriminate pairs of monosyllabic stimuli with contrasting consonants to test speech discrimination without using a working‐memory load. In the second protocol, subjects were exposed to two‐ to five‐syllabic non‐word pairs with contrasting vowels in order to test speech discrimination with a working‐memory load. The subjects classified the pairs as being either the same or different in both experiments. No significant differences were found between the subject groups in the discrimination task with monosyllables. When exposed to the two‐ to five‐syllabic stimuli, the ADHD+ group scored significantly lower than both other groups. This was attributed to a higher sensitivity to working‐memory load. Some possible explanations of this effect are discussed.

Children with autism spectrum disorders who do not develop phrase speech in the preschool years

There is uncertainty about the proportion of children with autism spectrum disorders who do not develop phrase speech during the preschool years. The main purpose of this study was to examine this ratio in a population-based community sample of children. The cohort consisted of 165 children (141 boys, 24 girls) with autism spectrum disorders aged 4–6 years followed longitudinally over 2 years during which time they had received intervention at a specialized autism center. In this study, data collected at the 2-year follow-up were used. Three categories of expressive language were defined: nonverbal, minimally verbal, and phrase speech. Data from the Vineland Adaptive Behavior Scales-II were used to classify expressive language. A secondary objective of the study was to analyze factors that might be linked to verbal ability, namely, child age, cognitive level, autism subtype and severity of core autism symptoms, developmental regression, epilepsy or other medical conditions, and intensity of intervention. The proportion of children who met the criteria for nonverbal, minimally verbal, and phrase speech were 15%, 10%, and 75%, respectively. The single most important factor linked to expressive language was the child’s cognitive level, and all children classified as being nonverbal or minimally verbal had intellectual disability.

Temporal Resolution of Auditory Perception in Relation to Perception, Memory, and Language Skills in Typical Children

This study examined temporal resolution of auditory perception (TRAP) in relation to speech perception and phonological working memory in one experiment and in relation to measures of rapid naming, understanding of grammatical contrasts, and phonological awareness in a second experiment. In the TRAP test, 6- to 9-year-old children discriminated four pairs of two sine tones, 878 Hz and 1350 Hz, presented in blocks with stepwise decreasing interstimulus intervals from 256 ms to 8 ms. In Experiment 1, weak but significant correlations between TRAP and speech perception and phonological working memory were found, as well as a significantly lower TRAP performance by girls. Experiment 2 indicated a significant relation between TRAP and the phonological awareness task. The results give qualified support to the notion of a weak relationship between TRAP and speech perception and language skills among typical children. However, the gender differences in TRAP performance, the limited variance explained by the regression models, and the finding that only one of the language parameters correlated with TRAP do not support the notion of a causal relationship between language skills and TRAP. The possibility that TRAP is connected to general neurological maturation rather than specifically to language abilities is discussed.

Language lateralization in children aged 10 to 11 years: a combined fMRI and dichotic listening study.

Objective The aims of this study were to develop and assess a method to map language networks in children with two auditory fMRI protocols in combination with a dichotic listening task (DL). The method is intended for pediatric patients prior to epilepsy surgery. To evaluate the potential clinical usefulness of the method we first wanted to assess data from a group of healthy children. Methods In a first step language test materials were developed, intended for subsequent implementation in fMRI protocols. An evaluation of this material was done in 30 children with typical development, 10 from the 1st, 4th and the 7th grade, respectively. The language test material was then adapted and implemented in two fMRI protocols intended to target frontal and posterior language networks. In a second step language lateralization was assessed in 17 typical 10–11 year olds with fMRI and DL. To reach a conclusion about language lateralization, firstly, quantitative analyses of the index data from the two fMRI tasks and the index data from the DL task were done separately. In a second step a set of criteria were applied to these results to reach a conclusion about language lateralization. The steps of these analyses are described in detail. Results The behavioral assessment of the language test material showed that it was well suited for typical children. The results of the language lateralization assessments, based on fMRI data and DL data, showed that for 15 of the 17 subjects (88%) a conclusion could be reached about hemispheric language dominance. In 2 cases (12%) DL provided critical data. Conclusions The employment of DL combined with language mapping using fMRI for assessing hemispheric language dominance is novel and it was deemed valuable since it provided additional information compared to the results gained from each method individually.

Teenage outcomes after speech and language impairment at preschool age

Aim Ten years ago, we published developmental data on a representative group of children (n = 25) with moderate or severe speech and language impairment, who were attending special preschools for children. The aim of this study was to perform a follow-up of these children as teenagers. Methods Parents of 23 teenagers participated in a clinical interview that requested information on the child’s current academic achievement, type of school, previous clinical assessments, and developmental diagnoses. Fifteen children participated in a speech and language evaluation, and 13 participated in a psychological evaluation. Results Seven of the 23 teenagers had a mild intellectual disability, and another three had borderline intellectual functioning. Nine had symptoms of disorders on the autism spectrum; five of these had an autism spectrum disorder, and four had clear autistic traits. Six met criteria for attention-deficit hyperactivity disorder (ADHD)/subthreshold ADHD. Thirteen of 15 teenagers had a moderate or severe language impairment, and 13 of 15 had a moderate or severe reading impairment. Overlapping disorders were frequent. None of the individuals who underwent the clinical evaluation were free from developmental problems. Conclusion A large number of children with speech and language impairment at preschool age had persistent language problems and/or met the criteria for developmental diagnoses other than speech and language impairment at their follow-up as teenagers. Language impairment in young children is a marker for several developmental disorders, particularly intellectual disability and autism spectrum disorder.

Presurgical language lateralization assessment by fMRI and dichotic listening of pediatric patients with intractable epilepsy

Objective The aim of this study was to evaluate the clinical use of a method to assess hemispheric language dominance in pediatric candidates for epilepsy surgery. The method is designed for patients but has previously been evaluated with healthy children. Methods Nineteen patients, 8–18 years old, with intractable epilepsy and candidates for epilepsy surgery were assessed. The assessment consisted of two functional MRI protocols (fMRI) intended to target frontal and posterior language networks respectively, and a behavioral dichotic listening task (DL). Regional left/right indices for each fMRI task from the frontal, temporal and parietal lobe were calculated, and left/right indices of the DL task were calculated from responses of consonants and vowels, separately. A quantitative analysis of each patients data set was done in two steps based on clearly specified criteria. First, fMRI data and DL data were analyzed separately to determine whether the result from each of these assessments were conclusive or not. Thereafter, the results from the individual assessments were combined to reach a final conclusion regarding hemispheric language dominance. Results For 14 of the 19 subjects (74%) a conclusion was reached about their hemispheric language dominance. Nine subjects had a left-sided and five subjects had a right-sided hemispheric dominance. In three cases (16%) DL provided critical data to reach a conclusive result. Conclusions The success rate of conclusive language lateralization assessments in this study is comparable to reported rates on similar challenged pediatric populations. The results are promising but data from more patients than in the present study will be required to conclude on the clinical applicability of the method.