Hemispheric function in developmental language disorders and high-level autism

The fuzzy boundaries of the social (pragmatic) communication disorder (SPCD): Why the picture is still so confusing?

Introduction

Since the introduction of Social (Pragmatic) Communication Disorder (SPCD) in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) in 2013, a debate has arisen in the scientific community about its usefulness in differential diagnosis for other clinical categories such as Autism Spectrum Disorder (ASD) and Specific Language Impairment (SLI). Indeed, SPCD criteria share a common deficit in communication and pragmatic skills with these diagnostic entities. Available assessment tools seem scarce and not sensitive enough to clarify diagnostic criteria and clinical boundaries. This study aims to review the existing literature on diagnostic screening for SPCD to highlight confounding variables in the domains examined, overlap with other diagnostic entities, and lack of specificity of available assessment tools in identifying the core deficits of the disorder.

Methods

The search strategy was defined by combining the following keywords: "social pragmatic communication disorder," "DSM-5," "differential diagnosis," and "child." The search was performed in three databases: Medline (PubMed), Scopus, and Web of Science. All studies published between 2013 and April 2023, written in English, and with a major focus on SPCD were included in the review.

Results

After the screening for the eligibility, 18 studies were included in the review. Most of these studies aimed to investigate the differential diagnosis between SPCD and other diagnostic categories (e.g., specific language impairment and autism spectrum disorder). Of these researches, only 6 were ad hoc experimental studies, while the others were based on previously collected databases.

Conclusions

SPCD seems to have its own peculiarities and characteristics, indicating its clinical relevance, as emphasized by the DSM-5. However, the lack of specific instruments and a number of confounding variables make it difficult to identify and differentiate SPCD from other diagnostic entities. Further research is needed to overcome the lack of specific clinical instruments and lack of empirical studies.

Questioning the Validity of the Semantic-Pragmatic Syndrome Diagnosis

The classification of developmental language disorders has recently witnessed the birth of a subsyndrome, semantic-pragmatic syndrome, used to describe the case of children with specific language and communication impairments. However, there are striking similar-ities between children with semantic-pragmatic syndrome and those with high-functioning autism on a communicative, behavioural and cognitive level. This article questions the validity of semantic-prag-matic syndrome as a diagnostic concept distinct from high-function-ding autism and, consequently, its use as a clinical entity.

Language Profiles in Children with Autism

The profile of language abilities in autism was examined by giving a number of standardized language assessments to a group of 1 20 children with autism. These assessments included measures of comprehension and of production of both vocabulary and grammar. Contrary to initial predictions, the group performed at a similar level across the range of tests, showing a relatively uniform profile of language attainment. In addition, there was no evidence of different language profiles in any diagnostic subgroup of children, such as children diagnosed as having Asperger syndrome. The theoretical implications of these findings, and their practical implications for research methodology, are discussed.

Autistic disorder in patients with Williams-Beuren syndrome: a reconsideration of the Williams-Beuren syndrome phenotype

BACKGROUND

Williams-Beuren syndrome (WBS), a rare developmental disorder caused by deletion of contiguous genes at 7q11.23, has been characterized by strengths in socialization (overfriendliness) and communication (excessive talkativeness). WBS has been often considered as the polar opposite behavioral phenotype to autism. Our objective was to better understand the range of phenotypic expression in WBS and the relationship between WBS and autistic disorder.

METHODOLOGY

The study was conducted on 9 French individuals aged from 4 to 37 years old with autistic disorder associated with WBS. Behavioral assessments were performed using Autism Diagnostic Interview-Revised (ADI-R) and Autism Diagnostic Observation Schedule (ADOS) scales. Molecular characterization of the WBS critical region was performed by FISH.

FINDINGS

FISH analysis indicated that all 9 patients displayed the common WBS deletion. All 9 patients met ADI-R and ADOS diagnostic criteria for autism, displaying stereotypies and severe impairments in social interaction and communication (including the absence of expressive language). Additionally, patients showed improvement in social communication over time.

CONCLUSIONS

The results indicate that comorbid autism and WBS is more frequent than expected and suggest that the common WBS deletion can result in a continuum of social communication impairment, ranging from excessive talkativeness and overfriendliness to absence of verbal language and poor social relationships. Appreciation of the possible co-occurrence of WBS and autism challenges the common view that WBS represents the opposite behavioral phenotype of autism, and might lead to improved recognition of WBS in individuals diagnosed with autism.

Corpus callosum differences associated with persistent stuttering in adults

Recent studies have implicated anatomical differences in speech-relevant brain regions of adults who stutter (AWS) compared to normally fluent adults (NFA). The present study focused on the region of the corpus callosum (CC) which is involved in interhemispheric processing between the left and right cerebral hemispheres. Two-dimensional segmentation of area and voxel-based morphometry were used to evaluate the corpus callosum. Results revealed that the rostrum and anterior midbody of the CC were larger in AWS than NFA. In addition, the overall callosa area was larger in AWS than NFA. The group comparison of white matter volume showed a cluster of increased white matter volume predominantly encompassing the rostrum across the midline portion in AWS. These results potentially reflect anatomical changes associated with differences in the hemispheric distribution of language processes that have been reported previously in AWS.

Theory of Mind disruption and recruitment of the right hemisphere during narrative comprehension in autism

The intersection of Theory of Mind (ToM) processing and complex narrative comprehension in high functioning autism was examined by comparing cortical activation during the reading of passages that required inferences based on either intentions, emotional states, or physical causality. Right hemisphere activation was substantially greater for all sentences in the autism group than in a matched control group suggesting decreased LH capacity in autism resulting in a spillover of processing to RH homologs. Moreover, the ToM network was disrupted. The autism group showed similar activation for all inference types in the right temporo-parietal component of the ToM network whereas the control participants selectively activated this network only when appropriate. The autism group had lower functional connectivity within the ToM network and also between the ToM and a left hemisphere language network. Furthermore, the within-network functional connectivity in autism was correlated with the size of the anterior portion of the corpus callosum.

Children on the borderlands of autism: differential characteristics in social, imaginative, communicative and repetitive behaviour domains

A sample of 37 children aged 4-7 years who all showed some autistic features was investigated. Children with a primary diagnosis of autism were compared with those diagnosed with a language disorder, on behaviours within four domains; social behaviour, imaginative activities, repetitive behaviour and communication. The aim was to identify potentially differentiating features of the two groups using observational ratings and questionnaire measures provided by parents and teachers. Information on participants' intelligence and language skills was also collected. The children with autism showed greater deficits in joint attention, functional play and pragmatic language, and engaged in more repetitive behaviours, than the language disordered children. However, the groups did not differ significantly on formally assessed language skills. A cluster analysis produced three groups of children varying in level of functioning and parent-rated behaviours. The results are informative for clinicians dealing with the challenge of differential diagnosis.

Visual perceptual impairment in children at 5 years of age with perinatal haemorrhagic or ischaemic brain damage in relation to cerebral magnetic resonance imaging

Children with perinatally acquired parenchymal haemorrhage are thought to have better visual perceptual skills than those with leukomalacia. We examined seven prematurely born children with parenchymal haemorrhage and 14 with grades 2-4 leukomalacia, at the age of 5 years. Clinical and magnetic resonance imaging parameters were related to visual perceptual performance assessed with the L94, using performance age. Belonging to the leukomalacia group, the inability to walk, a diminished peritrigonal white matter, a high degree of gliosis and cortical damage were associated with poorer visuo-perceptual skills. Enlarged lateral ventricles, confirming the findings of Melhelm (Radiology 214 (2000) 199), were associated with both cognitive, perceptual and motor problems and probably reflect the considerable extent of the brain damage. Specific factors protecting against visual perceptual impairment were a preserved volume of the right optical radiation and of the splenium of the corpus callosum. Children with leukomalacia are at considerable risk of visual perceptual impairment. Children with right-sided parenchymal haemorrhages also appear to be at risk although they function much better due to better motor and cognitive skills.

Nonverbal learning disability: a tutorial for speech-language pathologists

Nonverbal learning disability (NLD) is a diagnostic category that is unfamiliar to most speech-language pathologists. This brief tutorial describes NLD's characteristics, a theoretical model proposed to explain its source, and areas of overlap between NLD and similar diagnostic categories. The communicative profile, made up of difficulties in pragmatic and semantic language in the presence of relatively preserved syntactic skill, is also discussed. Empirical evidence relevant to NLD is also evaluated. Many questions remain unresolved, but until systematic research provides definitive answers, speech-language pathologists are encouraged to rely on careful description of the individual child's communicative strengths and weaknesses to identify appropriate targets and to focus intervention on improving the child's ability to communicate effectively in everyday contexts.

Language abilities of siblings of children with autism

BACKGROUND

Language abilities of siblings of children with autism were examined to explore the possibility that language abilities are behavioral markers specific to the genetic liability for autism, as part of the broader phenotype.

METHOD

Language abilities were compared among 27 siblings of children with autism, 23 siblings of children with mental retardation of unknown etiology (MR), and 22 siblings of children with developmental language disorders (DLD). Groups were matched by siblings' age, gender, birth order, family size, ethnicity, family income and by probands' gender and mental age.

RESULTS

Siblings of children with autism achieved higher scores than siblings of children with DLD on receptive, expressive, and total language scales of the Children's Evaluation of Language Fundamentals and on verbal IQ. Moreover, within the DLD group, school problems in the domains of reading and arithmetic were more prevalent than within the other two groups. Only 2 siblings of children with autism received clinical diagnoses based on DSM-IV criteria compared to 3 siblings of children with MR and 7 siblings of children with DLD.

CONCLUSIONS

After excluding data of the diagnosed siblings, no differences in language abilities could be discerned among the groups, except that more siblings in the DLD group were identified as having language difficulties. In summary, although language deficits characterize autism, siblings of children with autism were not found to demonstrate deficits in language skills assessed by formal language tests, IQ, or academic skills.

Exploring the borderlands of autistic disorder and specific language impairment: a study using standardised diagnostic instruments

BACKGROUND

Two studies were conducted to test claims that pragmatic language impairment (PLI - previously referred to as semantic-pragmatic disorder) is simply another term for autistic disorder or pervasive developmental disorder not otherwise specified (PDDNOS).

METHOD

In Study 1, 21 children aged from 6 to 9 years with language impairments were subdivided on the basis of the Children's Communication Checklist into 13 cases of pragmatic language impairment (PLI) and eight cases of typical specific language impairment (SLI-T). Parents completed the Autism Diagnostic Interview - Revised (ADI-R) and the Social Communication Questionnaire (SCQ), and the children were given the Autism Diagnostic Observation Schedule - Generic (ADOS-G). In Study 2, a further 11 children with SLI-T and 18 with PLI were assessed using the SCQ and ADOS-G. In addition, six children diagnosed with high-functioning autism and 18 normally developing children were assessed.

RESULTS

There was good agreement between ADI-R and SCQ diagnoses, but poor agreement between diagnoses based on these parental report measures and those based on ADOS-G. In many children, symptom profiles changed with age. Four PLI children from Study 1 and one from Study 2 met criteria for autistic disorder on both parental report (ADI-R or SCQ) and ADOS-G. Many of the others showed some autistic features, but there was a subset of children with pragmatic difficulties who were not diagnosed as having autism or PDDNOS by either instrument. These children tended to use stereotyped language with abnormal intonation/prosody, but they appeared sociable and communicative, had normal nonverbal communication, and showed few abnormalities outside the language/social communication domains.

CONCLUSIONS

Presence of pragmatic difficulties in a child with communication problems should prompt the clinician to evaluate autistic symptomatology, but it is dangerous to assume that all children with pragmatic difficulties have autism or PDDNOS.

The differential diagnosis of impaired reciprocal social interaction in children: a review of disorders

Impairment in reciprocal social interaction in children that is less severe than autism can be difficult to diagnose due to the variety of developmental pathways that may lead to this problem. Seven childhood disorders are reviewed that include impaired reciprocal interaction: multisystem developmental disorder, nonverbal learning disability syndrome, semantic-pragmatic disorder, attachment disorders (including a developmental theory of limbic system damage), multiplex developmental disorder, schizoid personality disorder, and pervasive developmental disorder not otherwise specified. Clarification is needed for most of the disorders in the areas of operationalized criteria, assessment tools, and documenting causal relationships.

Brain mapping of language and auditory perception in high-functioning autistic adults: a PET study

We examined the brain organization for language and auditory functions in five high-functioning autistic and five normal adults, using [15O]-water positron emission tomography (PET). Cerebral blood flow was studied for rest, listening to tones, and listening to, repeating, and generating sentences. The autism group (compared to the control group) showed (a) reversed hemispheric dominance during verbal auditory stimulation; (b) a trend towards reduced activation of auditory cortex during acoustic stimulation; and (c) reduced cerebellar activation during nonverbal auditory perception and possibly expressive language. These results are compatible with findings of cerebellar anomalies and may suggest a tendency towards atypical dominance for language in autism.

Normal intrasylvian anatomical asymmetry in children with developmental language disorder

Symmetry of posterior intrasylvian cortices (e.g., planum temporale, planum parietale) has been suggested to represent a risk factor for developmental disorders of language and reading. Using high-resolution magnetic resonance morphometry, we studied 21 right-handed children with developmental language disorder of the phonologic-syntactic type, and found normal left-right asymmetry of the planum temporale and planum parietale when compared with 21 matched controls. The planum temporale was bilaterally smaller in the affected children, a finding accounted for by their approximately 7% smaller forebrain size. Our data do not support a role of gross visible unilateral or bilateral abnormalities of posterior intrasylvian ontogenesis in this disorder.

Social cognition in developmental language disorders and high-level autism

Two groups of children with contrasting types of developmental language disorder (phonologic-syntactic and semantic-pragmatic) were compared with a group of children with high-level autism and with a control group of normal children on tests of social cognition (theory of mind; social comprehension; and detection of eye direction). The similarly poor performances of the semantic-pragmatic group and the autistic group suggest that semantic-pragmatic language disorder lies on the autistic spectrum.