Behavioral phenotype of individuals with Down syndrome

Augmentative and Alternative Communication Supports for Language and Literacy in Preschool: Considerations for Down Syndrome and Autism Spectrum Disorder

Children with Down syndrome and children with autism spectrum disorder have a range of speech abilities during preschool that impacts access to both language and literacy instruction. It is the responsibility of the speech-language pathologist to advocate for and provide intervention using augmentative and alternative communication (AAC) through individualized assessment. This article provides a review of the literature supporting the use of AAC during preschool for both language and literacy development in children with Down syndrome and children with autism spectrum disorder who have limited speech. A small scale exploratory report is discussed to highlight differences in early literacy skills found in children in each group. Implications for AAC intervention during preschool to support both language and literacy are discussed.

Profiling Basal Forebrain Cholinergic Neurons Reveals a Molecular Basis for Vulnerability Within the Ts65Dn Model of Down Syndrome and Alzheimer's Disease

Basal forebrain cholinergic neuron (BFCN) degeneration is a hallmark of Down syndrome (DS) and Alzheimer's disease (AD). Current therapeutics have been unsuccessful in slowing disease progression, likely due to complex pathological interactions and dysregulated pathways that are poorly understood. The Ts65Dn trisomic mouse model recapitulates both cognitive and morphological deficits of DS and AD, including BFCN degeneration. We utilized Ts65Dn mice to understand mechanisms underlying BFCN degeneration to identify novel targets for therapeutic intervention. We performed high-throughput, single population RNA sequencing (RNA-seq) to interrogate transcriptomic changes within medial septal nucleus (MSN) BFCNs, using laser capture microdissection to individually isolate ~500 choline acetyltransferase-immunopositive neurons in Ts65Dn and normal disomic (2N) mice at 6 months of age (MO). Ts65Dn mice had unique MSN BFCN transcriptomic profiles at ~6 MO clearly differentiating them from 2N mice. Leveraging Ingenuity Pathway Analysis and KEGG analysis, we linked differentially expressed gene (DEG) changes within MSN BFCNs to several canonical pathways and aberrant physiological functions. The dysregulated transcriptomic profile of trisomic BFCNs provides key information underscoring selective vulnerability within the septohippocampal circuit. We propose both expected and novel therapeutic targets for DS and AD, including specific DEGs within cholinergic, glutamatergic, GABAergic, and neurotrophin pathways, as well as select targets for repairing oxidative phosphorylation status in neurons. We demonstrate and validate this interrogative quantitative bioinformatic analysis of a key dysregulated neuronal population linking single population transcript changes to an established pathological hallmark associated with cognitive decline for therapeutic development in human DS and AD.

Bilingualism in children with a dual diagnosis of Down syndrome and Autism Spectrum Disorder

Research shows that a substantial proportion of children with Down syndrome (DS) also meet the clinical criteria for Autism Spectrum Disorder (ASD). Children with this dual diagnosis display a linguistic profile that includes significant language delays and language impairments which often differ from the impairments observed in each developmental disability (DD) separately. Given the challenges observed with language acquisition for children with DS-ASD, concerns might be raised regarding the outcomes and suitability of a bilingual environment for children with this dual diagnosis specifically. The aim of this research was to explore the language profiles of four children with DS-ASD. A multiple case-study approach was employed. Four children with a confirmed DS-ASD diagnosis who had received exposure to two languages (English and Welsh) were assessed on a range of cognitive and linguistic measures. Performance was compared to three control groups; bilinguals with DS, English monolinguals with DS and mental age-matched typically developing bilinguals. Assessments comprised of expressive and receptive language, phonological awareness, working memory and non-verbal cognitive abilities. Considerable variability was found in the cognitive and linguistic profiles of the case-study participants. Children with DS-ASD displayed similar language profiles to that of the bilingual and monolingual children with DS in the areas tested, although performance was generally lower than that of the TD bilingual children. Although substantial variability was found, participants were developing bilingual abilities in a similar trajectory to children with DS in line with the degree of exposure to each language. This research highlights the need to assess bilingual children with complex dual diagnoses with an individualistic approach and carefully consider how to appropriately assess and treat bilingual children within speech and language therapy provisions.

Low speech rate but high gesture rate during conversational interaction in people with Cornelia de Lange syndrome

BACKGROUND

Cornelia de Lange syndrsome (CdLS) is a rare genetic syndrome with notable impaired expressive communication characterised by reduced spoken language. We examined gesture use to refine the description of expressive communication impairments in CdLS.

METHODS

During conversations, we compared gesture use in people with CdLS to peers with Down syndrome (DS) matched for receptive language and adaptive ability, and typically developing (TD) individuals of similar chronological age.

RESULTS

As anticipated the DS and CdLS groups used fewer words during conversation than TD peers (P < .001). However, the CdLS group used twice the number of gestures per 100 words compared with the DS and TD groups (P = .003).

CONCLUSIONS

Individuals with CdLS have a significantly higher gesture rate than expected given their level of intellectual disability and chronological age. This result indicates the cause of reduced use of spoken language does not extend to all forms of expressive communication.

Learning Through Shared Care : Allomaternal Care Impacts Cognitive Development in Early Infancy in a Western Population

This study investigates how allomaternal care (AMC) impacts human development outside of energetics by evaluating relations between important qualitative and quantitative aspects of AMC and developmental outcomes in a Western population. This study seeks to determine whether there are measurable differences in cognitive and language outcomes as predicted by differences in exposure to AMC via formal (e.g., childcare facilities) and informal (e.g., family and friends) networks. Data were collected from 102 mothers and their typically developing infants aged 13-18 months. AMC predictor data were collected using questionnaires, structured daily diaries, and longitudinal interviews. Developmental outcomes were assessed using the Cognitive, Receptive Language, and Expressive Language subtests of the Bayley III Screening Test. Additional demographic covariates were also evaluated. Akaike Information Criterion (AIC)-informed model selection was used to identify the best-fitting model for each outcome across three working linear regression models. Although AMC variables had no significant effects on Receptive and Expressive Language subtest scores, highly involved familial AMC had a significant medium effect on Cognitive subtest score (β = 0.23, p < 0.01, semi-partial r = 0.28). Formal childcare had no effect on any outcome. This study provides preliminary evidence that there is a measurable connection between AMC and cognitive development in some populations and provides a methodological base from which to assess these connections cross-culturally through future studies. As these effects are attributable to AMC interactions with networks of mostly related individuals, these findings present an area for further investigation regarding the kin selection hypothesis for AMC.

Parent-based training of basic number skills in children with Down syndrome using an adaptive computer game

BACKGROUND

Numeracy is an area of difficulty for children with Down syndrome (DS). It has been demonstrated that The Number Race, a non-commercial adaptive computer game designed to foster basic mathematical abilities, represents a promising instrument to enhance these skills in children with DS when delivered by an expert in a clinical setting.

AIMS

In the present study, we assessed the efficacy of The Number Race when administered at home by properly instructed and remotely supervised parents.

METHODS AND PROCEDURES

Basic numerical skills were assessed before and after training, as well as at three-months follow-up. Performance of children with DS who worked at home with the parent (PG) was compared with that of children who received the training by an expert (EG). For both groups, the training lasted ten weeks, with two weekly sessions of 20-30 min.

OUTCOMES AND RESULTS

Results show that both groups improved across various measures of numerical proficiency, including the overall score of the numeracy assessment battery, while only the EG showed an improvement in a measure of mental calculation. The improvements were maintained three months after the end of the training.

CONCLUSIONS AND IMPLICATIONS

These findings confirm the efficacy of The Number Race and extend it to an home-based setting, whereby parents administer the training with external supervision.

Cognitive and Adaptive Characterization of Children and Adolescents with KBG Syndrome: An Explorative Study

KBG syndrome (KBGS) is a rare Mendelian condition caused by heterozygous mutations in ANKRD11 or microdeletions in chromosome 16q24.3 encompassing the gene. KBGS is clinically variable, which makes its diagnosis difficult in a significant proportion of cases. The present study aims at delineating the cognitive profile and adaptive functioning of children and adolescents with KBGS. Twenty-four Italian KBGS with a confirmed diagnosis by molecular testing of the causative ANKRD11 gene were recruited to define both cognitive profile as measured by the Wechsler Intelligence Scale and adaptive functioning as measured by Vineland Adaptive Behavior Scales-II Edition or the Adaptive Behavior Assessment System-II Edition. Among children and adolescents, 17 showed intellectual disability, six presented borderline intellectual functioning and only one child did not show cognitive defects. Concerning cognitive profile, results revealed significant differences between the four indexes of Wechsler Intelligence Scale. Namely, the verbal comprehension index was significantly higher than the perceptual reasoning index, working memory index and the processing speed index. Concerning adaptive functioning, no difference between the domains was found. In conclusion, in our cohort, a heterogeneous profile has been documented in cognitive profiles, with a spike on verbal comprehension, while a flat-trend has emerged in adaptive functioning. Our cognitive and adaptive characterization drives professionals to set the best clinical supports, capturing the complexity and heterogeneity of this rare condition.

Signalling pathways contributing to learning and memory deficits in the Ts65Dn mouse model of Down syndrome

Down syndrome (DS) is a genetic trisomic disorder that produces life-long changes in physiology and cognition. Many of the changes in learning and memory seen in DS are reminiscent of disorders involving the hippocampal/entorhinal circuit. Mouse models of DS typically involve trisomy of murine chromosome 16 is homologous for many of the genes triplicated in human trisomy 21, and provide us with good models of changes in, and potential pharmacotherapy for, human DS. Recent careful dissection of the Ts65Dn mouse model of DS has revealed differences in key signalling pathways from the basal forebrain to the hippocampus and associated rhinal cortices, as well as changes in the microstructure of the hippocampus itself. In vivo behavioural and electrophysiological studies have shown that Ts65Dn animals have difficulties in spatial memory that mirror hippocampal deficits, and have changes in hippocampal electrophysiological phenomenology that may explain these differences, and align with expectations generated from in vitro exploration of this model. Finally, given the existing data, we will examine the possibility for pharmacotherapy for DS, and outline the work that remains to be done to fully understand this system.

Path Learning in Individuals With Down Syndrome: The Challenge of Learning Condition and Cognitive Abilities

Analyzing navigational abilities and related aspects in individuals with Down syndrome (DS) is of considerable interest because of its relevance to everyday life. This study investigates path learning, the conditions favoring it, and the cognitive abilities involved. A group of 30 adults with DS and 32 typically-developing (TD) children matched on receptive vocabulary were shown a 4 × 4 Floor Matrix and asked to repeat increasingly long sequences of steps by walking on the grid. The sequences were presented under two learning conditions, one called Oral instructions (participants received verbal instructions such as “turn right” or “turn left”), the other Observation (participants watched the experimenter's moves). Participants were also assessed on verbal and visuospatial cognitive measures. The results showed a similarly better performance in both groups when the Floor Matrix task was administered in the Observation as opposed to the Oral instructions condition. As for the relation with cognitive abilities, in the Floor Matrix task in the Oral instructions condition, individuals with DS showed an effect of both verbal and visuospatial abilities, which was only positive for verbal ability. The effect of verbal and visuospatial abilities was negligible in the TD group. In the Observation condition, performance was predicted by sequential working memory in both groups. Overall, these results shed light on path learning in individuals with DS, showing that they benefited from the Observation condition, and that the involvement of their cognitive abilities depended on the learning condition.

Exploring Expressive Communication Skills in a Cross-Sectional Sample of Individuals With a Dual Diagnosis of Autism Spectrum Disorder and Down Syndrome

Individuals with a comorbid diagnosis of Down syndrome (DS) and autism spectrum disorder (ASD) have been found to exhibit greater deficits in expressive communication than individuals with DS only. We hypothesized that individuals with a comorbid diagnosis (n = 430) would have significantly lower Communication Matrix scores and specifically social communication scores than individuals with DS alone (n = 4,352). In a sample of 4,782 individuals with DS, scores for individuals with a comorbid diagnosis were on average 18.01 points and 7.26 points lower for total score and social score respectively as compared to individuals with DS. Comorbid diagnosis accounted for 10.5% of the variance in communication scores. Between-group differences in referential gestures and symbolic communication behaviors were also observed.

Early appearance of developmental alterations in the dendritic tree of the hippocampal granule cells in the Ts65Dn model of Down syndrome

Down syndrome (DS), a genetic condition caused by triplication of chromosome 21, is characterized by alterations in various cognitive domains, including hippocampus-dependent memory functions, starting from early life stages. The major causes of intellectual disability in DS are prenatal neurogenesis alterations followed by impairment of dendritic development in early infancy. While there is evidence that the Ts65Dn mouse, the most widely used model of DS, exhibits dendritic alterations in adulthood, no studies are available regarding the onset of dendritic pathology. The goal of the current study was to establish whether this model exhibits early dendritic alterations in the hippocampus, a region whose function is severely damaged in DS. To this purpose, in Golgi-stained brains, we evaluated the dendritic arborization and dendritic spines of the granule cells of the hippocampal dentate gyrus in Ts65Dn mice aged 8 (P8) and 15 (P15) days. While P15 Ts65Dn mice exhibited a notably hypotrophic dendritic arbor and a reduced spine density, P8 mice exhibited a moderate reduction in the number of dendritic ramifications and no differences in spine density in comparison with their euploid counterparts. Both in P8 and P15 mice, spines were longer and had a longer neck, suggesting possible alterations in synaptic function. Moreover, P8 and P15 Ts65Dn mice had more thin spines and fewer stubby spines in comparison with euploid mice. Our study provides novel evidence on the onset of dendritic pathology, one of the causes of intellectual disability in DS, showing that it is already detectable in the dentate gyrus of Ts65Dn pups. This evidence strengthens the suitability of this model of DS as a tool to study dendritic pathology in DS and to test the efficacy of early therapeutic interventions aimed at ameliorating hippocampal development and, therefore, memory functions in children with DS.

Decrease in the T-box1 gene expression in embryonic brain and adult hippocampus of down syndrome mouse models

Down syndrome (DS, Trisomy 21) is the most common genetic cause of delayed fetal brain development and postnatal intellectual disability. Although delayed fetal brain development might be involved in intellectual disability, no evidence of an association between these abnormal phenotypes has been shown. To identify molecules differentially expressed in both the prenatal forebrain and adult hippocampus of Ts1Cje mice, a mouse model of DS, we employed a transcriptomic analysis. In the present study, we conducted transcriptomic profiling of the hippocampus of adult Ts1Cje mice and compared the results with the previously obtained transcriptomic profile of the prenatal forebrain at embryonic day 14.5. Results showed that the Tbx1 mRNA expression was decreased at both life stages. In addition, the decreased expression of Tbx1 mRNA was confirmed in other DS mouse models, Dp(16)1Yey/+ and Ts1Rhr mice, which carry longer and shorter trisomic regions, respectively. Taken together, these findings suggest that Tbx1 may link the delayed fetal brain development and intellectual disability in DS.

A meta-analysis of prosody in autism, Williams syndrome, and Down syndrome

Prosody, the rhythm and melody of speech, is an important component of effective communication, and it is an area of difficulty for many populations who struggle with communication. This paper is a meta-analysis of nine studies (and two sets of unpublished data) that assessed prosody using the Profiling Elements of Prosody in Speech-Communication (PEPS-C; Peppé & McCann, 2003) in autism spectrum disorder, Williams syndrome, and Down syndrome. Our original goal was to include studies involving any neurodevelopmental disorder that is commonly associated with intellectual disability, yet our systematic search, which included three databases (i.e., PsychInfo, ERIC, and PubMed), only identified studies involving these three groups. To be included in the meta-analysis, studies had to include a group (n ≥ 3 participants) with a neurodevelopmental disorder commonly associated with intellectual disability and a typically developing comparison group matched on chronological age, nonverbal abilities, or verbal abilities. Studies also needed to report original data using the PEPS-C and be available in English. Study quality was assessed using a checklist adapted from Downes et al. (2016). Results revealed that prosodic form was a weakness for each etiology, while unique patterns of strengths and weaknesses were evident for prosodic functions. Groups with autism (n = 5), all classified as high-functioning or with Asperger's syndrome, exhibited weakness in emotional affect but some relative strengths with turn-end and focus tasks. Groups with Williams syndrome (n = 4) demonstrated weaknesses on phrase/sentence-level tasks and relative strengths on word-level tasks. Groups with Down syndrome (n = 2) had the greatest difficulty overall, though performance was better on receptive (vs. expressive) function tasks. By combining studies and related subtasks of the PEPS-C, we are able to more confidently generalize findings for each population and identify targets for intervention. However, given the limited number of studies identified, this paper also highlights the need for more research on prosody in intellectual disability.

Executive function in down syndrome children in Bogotá, Colombia

The study aim was to characterize executive function in 114 children with Down syndrome from a reference institution in Bogotá, Colombia. Children were screened with the Battelle Developmental Inventory to establish their developmental age. Eighty children with an equivalent mental age of 2–5.11 years were allocated to groups of 20 according to their mental age. Parents and teachers then completed the Behavior Rating Inventory of Executive Function-Preschool Version. We found a high variability and a low correlation between parent and teacher ratings. In general, children showed a specific profile characterized by weakness in the domains of working memory, shifting, planning, and organization, and strengths in the emotional control domain. These findings indicate a characteristic pattern of executive function in children with Down syndrome. This profile could form the basis for the planning of clinical assessment programs.

Down's syndrome and COVID-19: risk or protection factor against infection? A molecular and genetic approach

Down syndrome (DS) is the most common genetic cause of learning difficulties and intellectual disabilities. DS patients often present with several congenital defects and chronic diseases, including immunity disorders. Elevated levels of pro-inflammatory cytokines such as interleukin (IL)-6 and tumor necrosis factor alpha (TNF-α) have been seen, which appear to vary with age. At birth, patients present with combined immunodeficiency, with frequent infections that decrease with age. Furthermore, high levels of IL-4 and IL-10 with anti-inflammatory properties and low levels of IL-6 and TNF-α are described in children. The immune system is believed to play an essential role in SARS-CoV-2 pathogenesis, and it has been associated with elevated levels of pro-inflammatory cytokines and an exaggerated cytokine release syndrome (CRS) that may eventually trigger a severe situation called cytokine storm. On the other hand, genetic features seem to be involved in the predisposition to illness and its severity. Overexpression of DSCR1 and ZAKI-4 inhibits the translocation of activated T lymphocyte nuclear factor (NF-AT) to the nucleus, a main step in the inflammatory responsiveness. We discuss here the possible role of immunology and genetic features of DS in the infection and prognosis in COVID-19.

Narrative Abilities of Adults' With Down Syndrome as a Window to Their Morphosyntactic, Socio-Cognitive, and Prosodic Abilities

Down syndrome (DS) is the most common developmental disorder characterized by mild to moderate intellectual disability. Several studies have reported poor language and prosodic skills and contradictory results regarding individuals’ with DS socio-cognitive skills, whereas most of them have focused on children with DS. The present study attempts to explore adults’ with DS language, socio-cognitive and prosodic abilities via the use of story-retellings. Twenty adults with DS and two groups of TD children, one matched to their expressive vocabulary (TD-EVT) and the other matched to their non-verbal mental age (TD-RCPM), took part in the present study. Participants listened to a story while viewing a wordless picture PowerPoint presentation on a computer screen, and then, they were instructed to retell the story while viewing the pictures for a second time. Each participant listened to two stories, one with “lively” and one with “flat” prosody. Results revealed that adults’ with DS performance was comparable with the one presented by the TD-RCPM group, whereas the TD-EVT group performed significantly better in almost all variables. Individuals’ with DS re-narrations, however, contained significantly less complement clauses and internal state terms (related or not related to Theory of Mind–ToM) compared to the re-narrations of both control groups. In contrast, the group with DS performed similarly to both control groups in comprehension questions related to main characters’ internal state terms and significantly better compared to the TD-RCPM group in questions related to ToM. In terms of prosody, all three groups performed significantly better on story structure and comprehension questions when prosody was “lively” compared “flat” prosody. DS group’s re-narrations did not contain enough internal state terms, not due to their inability in recognizing them, but due to their poor morphosyntactic abilities, which did not allow them to find the proper means to express the main characters’ internal states. Prosody facilitated participants with DS in the comprehension and re-narration. This suggests that intervention programs based on prosody could support the language skills of adults with DS.

Longitudinal neuroanatomical and behavioral analyses show phenotypic drift and variability in the Ts65Dn mouse model of Down syndrome

Mouse models of Down syndrome (DS) have been invaluable tools for advancing knowledge of the underlying mechanisms of intellectual disability in people with DS. The Ts(1716)65Dn (Ts65Dn) mouse is one of the most commonly used models as it recapitulates many of the phenotypes seen in individuals with DS, including neuroanatomical changes and impaired learning and memory. In this study, we use rigorous metrics to evaluate multiple cohorts of Ts65Dn ranging from 2014 to the present, including a stock of animals recovered from embryos frozen within ten generations after the colony was first created in 2010. Through quantification of prenatal and postnatal brain development and several behavioral tasks, our results provide a comprehensive comparison of Ts65Dn across time and show a significant amount of variability both across cohorts as well as within cohorts. The inconsistent phenotypes in Ts65Dn mice highlight specific cautions and caveats for use of this model. We outline important steps for ensuring responsible use of Ts65Dn in future research.This article has an associated First Person interview with the first author of the paper.

Goal-directed action planning in infants with Down syndrome

BACKGROUND

Down syndrome (DS) is a neurogenetic disorder associated with risk for executive dysfunction, or difficulties with the cognitive processes required for planning volitional, goal-directed behaviour. This study examines the developmental origins of difficulties with goal-directed action planning in infants with DS to inform our understanding of the cognitive phenotype associated with DS and its implications for intervention.

METHOD

First, the study compared the performance of infants with DS (n = 44, mean chronological age = 7.5 months, SD = 2.3) and typically developing infants (n = 31, mean chronological age = 7.5 months, SD = 2.9) on plan production and planning efficiency during an early planning task. Next, potential sources of variability in planning behaviour (motor performance and sensory processing) within the DS sample were examined. All infants completed an early planning laboratory task and the Bayley Scales of Infant Development-III Cognitive Scale. The motor and sensory skills of infants with DS were assessed by the motor scales of the Bayley Scales of Infant Development-III and the Infant Sensory Profile-2. DS-related biomedical history information was provided by caregivers for the infants with DS.

RESULTS

Between-group differences in planning were observed on the dimensions of strategy production and completion, such that infants with DS were less efficient in their strategy execution than typically developing infants. In the DS group, motor skills and sensory processing were associated with planning efficiency on all components of the early planning task.

CONCLUSIONS

Less efficient action planning in infants with DS may disrupt the shaping of goal-directed behaviour, and the identification of early risk factors associated with planning efficiency has important implications for early intervention.

A multi-level developmental approach to exploring individual differences in Down syndrome: genes, brain, behaviour, and environment

In this article, we focus on the causes of individual differences in Down syndrome (DS), exemplifying the multi-level, multi-method, lifespan developmental approach advocated by Karmiloff-Smith (1998, 2009, 2012, 2016). We evaluate the possibility of linking variations in infant and child development with variations in the (elevated) risk for Alzheimer's disease (AD) in adults with DS. We review the theoretical basis for this argument, considering genetics, epigenetics, brain, behaviour and environment. In studies 1 and 2, we focus on variation in language development. We utilise data from the MacArthur-Bates Communicative Development Inventories (CDI; Fenson et al., 2007), and Mullen Scales of Early Learning (MSEL) receptive and productive language subscales (Mullen, 1995) from 84 infants and children with DS (mean age 2;3, range 0;7 to 5;3). As expected, there was developmental delay in both receptive and expressive vocabulary and wide individual differences. Study 1 examined the influence of an environmental measure (socio-economic status as measured by parental occupation) on the observed variability. SES did not predict a reliable amount of the variation. Study 2 examined the predictive power of a specific genetic measure (apolipoprotein APOE genotype) which modulates risk for AD in adulthood. There was no reliable effect of APOE genotype, though weak evidence that development was faster for the genotype conferring greater AD risk (ε4 carriers), consistent with recent observations in infant attention (D'Souza, Mason et al., 2020). Study 3 considered the concerted effect of the DS genotype on early brain development. We describe new magnetic resonance imaging methods for measuring prenatal and neonatal brain structure in DS (e.g., volumes of supratentorial brain, cortex, cerebellar volume; Patkee et al., 2019). We establish the methodological viability of linking differences in early brain structure to measures of infant cognitive development, measured by the MSEL, as a potential early marker of clinical relevance. Five case studies are presented as proof of concept, but these are as yet too few to discern a pattern.

Obstructive Sleep Apnoea Contributes to Executive Function Impairment in Young Children with Down Syndrome

OBJECTIVE/BACKGROUND

Children with Down syndrome (DS) commonly experience difficulties with executive function (EF). They are also vulnerable to obstructive sleep apnoea (OSA). OSA is associated with EF deficits in typically developing children. A recent study reported an association between OSA and cognitive deficits in 38 school-aged children with DS. We experimentally investigated EF behaviours in young children with DS, and their association with OSA.

PARTICIPANTS AND METHODS

Children with DS were recruited to take part in a larger study of OSA (N = 202). Parents of 80 children (50 male) aged 36 to 71 months (M = 56.90, SD = 10.19 months) completed the Behavior Rating Inventory of Executive Function - Preschool Version (BRIEF-P). Of these 80 children, 69 were also successfully studied overnight with domiciliary cardiorespiratory polygraphy to diagnose OSA.

RESULTS

Obstructive apnoea/hypopnoea index was in the normal range (0-1.49/h) for 28 children but indicated OSA (≥1.5/h) in 41 children. Consistent with previous research, we found a large effect for children experiencing particular weaknesses in working memory, planning and organising, whilst emotional control was a relative strength. OSA was associated with poorer working memory (β = .23, R2 = .05, p = .025), emotional control (β = .20, R2 = .04, p = .047) and shifting (β = .24, R2 = .06, p = .023).

CONCLUSIONS

Findings suggest that known EF difficulties in DS are already evident at this young age. Children with DS already have limited cognitive reserve and can ill afford additional EF deficit associated with OSA. OSA is amenable to treatment and should be actively treated in these children to promote optimal cognitive development.

Impairment of spatial memory accuracy improved by Cbr1 copy number resumption and GABAB receptor-dependent enhancement of synaptic inhibition in Down syndrome model mice

Down syndrome is a complex genetic disorder caused by the presence of three copies of the chromosome 21 in humans. The most common models, carrying extra-copies of overlapping fragments of mouse chromosome 16 that is syntenic to human chromosome 21, are Ts2Cje, Ts1Cje and Ts1Rhr mice. In electrophysiological analyses using hippocampal slices, we found that the later phase of the depolarization during tetanic stimulation, which was regulated by GABA_B receptors, was significantly smaller in Ts1Cje and Ts2Cje mice than that in WT controls but not in Ts1Rhr mice. Furthermore, isolated GABA_B receptor-mediated inhibitory synaptic responses were larger in Ts1Cje mice. To our knowledge, this is the first report that directly shows the enhancement of GABA_B receptor-mediated synaptic currents in Ts1Cje mice. These results suggest that GABA_B receptor-mediated synaptic inhibition was enhanced in Ts1Cje and Ts2Cje mice but not in Ts1Rhr mice. The Cbr1 gene, which is present in three copies in Ts1Cje and Ts2Cje but not in Ts1Rhr, encodes carbonyl reductase that may facilitate GABA_B-receptor activity through a reduction of prostaglandin E2 (PGE2). Interestingly, we found that a reduction of PGE2 and an memory impairment in Ts1Cje mice were alleviated when only Cbr1 was set back to two copies (Ts1Cje;Cbr1^+/+/-). However, the GABA_B receptor-dependent enhancement of synaptic inhibition in Ts1Cje was unaltered in Ts1Cje;Cbr1^+/+/- mice. These results indicate that Cbr1 is one of the genes responsible for DS cognitive impairments and the gene(s) other than Cbr1, which is included in Ts1Cje but not in Ts1Rhr, is responsible for the GABA_B receptor-dependent over-inhibition.

Plasma metabolome and cognitive skills in Down syndrome

Trisomy 21 (Down syndrome, DS) is the main human genetic cause of intellectual disability (ID). Lejeune hypothesized that DS could be considered a metabolic disease, and we found that subjects with DS have a specific plasma and urinary metabolomic profile. In this work we confirmed the alteration of mitochondrial metabolism in DS and also investigated if metabolite levels are related to cognitive aspects of DS. We analyzed the metabolomic profiles of plasma samples from 129 subjects with DS and 46 healthy control (CTRL) subjects by 1H Nuclear Magnetic Resonance (NMR). Multivariate analysis of the NMR metabolomic profiles showed a clear discrimination (up to 94% accuracy) between the two groups. The univariate analysis revealed a significant alteration in 7 metabolites out of 28 assigned unambiguously. Correlations among the metabolite levels in DS and CTRL groups were separately investigated and statistically significant relationships appeared. On the contrary, statistically significant correlations among the NMR-detectable part of DS plasma metabolome and the different intelligence quotient ranges obtained by Griffiths-III or WPPSI-III tests were not found. Even if metabolic imbalance provides a clear discrimination between DS and CTRL groups, it appears that the investigated metabolomic profiles cannot be associated with the degree of ID.

Down syndrome: A curative prospect?

Experimental work regarding corrective actions on chromosomes and genes, and control of gene products is yielding promising results. It opens the way to advances in dealing with the etiological aspects of Down syndrome and may lead to important changes in the life of individuals affected with this condition. A small number of molecules are being investigated in pharmacological research that may have positive effects on intellectual functioning. Studies of the pathological consequences of the amyloid cascade and the TAU pathology in the etiology of Alzheimer disease (AD), which is more frequent and occuring earlier in life in persons with Down syndrome (DS), are presented. The search for biological markers of AD and ways for constrasting its early manifestations are also discussed.

Effect of Transcranial Direct Current Stimulation Combined With Xbox-Kinect Game Experience on Upper Limb Movement in Down Syndrome: A Case Report

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique used to enhance local synaptic efficacy and modulate the electrical activity of the cortex in neurological disorders. Researchers have sought to combine this type of stimulation with well-established therapeutic modalities, such as motor training involving Xbox Kinect games, which has demonstrated promising results. Thus, this study aimed to determine whether tDCS can enhance upper limb motor training in an eight-year-old child with Down Syndrome (DS) (cognitive age: five years, based on the Wechsler Intelligence Scale for Children). The evaluations consisted of three-dimensional analysis of upper limb kinematics during a reaching task performed before, after10 session, and one month after the intervention. The intervention protocol involved 1 20-min sessions of tDCS over the primary motor cortex at an intensity of 1 mA during Xbox Kinect game training involving an upper limb motor task. The analysis of the kinematic data revealed that in the pre-intervention evaluation, the dominant limb executed the task slowly and over a long path. These aspects improved at the post-intervention and follow-up evaluations, as demonstrated by the shorter total movement duration (3.05 vs. 1.58 vs. 1.52 s, respectively). Similar changes occurred with the non-dominant upper limb; a significant increase in movement velocity at the post-intervention and follow-up evaluations was observed (0.53 vs. 0.54 vs. 0.85 m/s, respectively). The present case report offers preliminary data from a protocol study, and the results confirm the notion that anodal tDCS combined with upper limb motor training leads to improvements in different kinematic variables.

The Population Prevalence, Associations of Congenital Heart Defect and Mortality Risk for Down's Syndrome in South Korea Based on National Health Insurance Service (NHIS) Data

Background

In the present study, we estimated the population prevalence, associations of congenital heart defect (CHD) and mortality risk for DS using data from National Health Insurance Service (NHIS) and Rare Diseases Registry (RDR).

Methods

We collected data on subjects with DS who were registered in the RDR between 2010 and 2015. To estimate associations of CHD and mortality risk of DS, the data of DS subjects were compared with 1:5 age- and sex-matched controls.

Results

In 2015, 2077 individuals with DS were identified out of the total population of 51,574,044 South Koreans and the prevalence was 4.03 per 100,000 persons. The trend of DS population prevalence across 10-year-old intervals showed a peak in the group under the age of 10 years (26.0 per 100,000 persons) and then declined sharply after the age of 20 years (0.98 per 100,000 persons at 30-39 years of age). In subjects with DS, the frequencies of atrial septal defect [odds ratios (OR) =65.9; 95% CI, 84.1-99.1], ventricular septal defect (OR = 88.1, 95% CI, 57.9-134.1), patent ductus arteriosus (OR = 56.9, 95% CI, 40.1-80.8), tetralogy of fallot (OR = 42.1, 95% CI, 19.3-92.3), or atrioventricular septal defect (OR = 510.0, 95% CI, 126.7-999.0) were higher than those of age- and sex-matched controls. The risk of death in patients with DS was significantly higher than that of age- and sex-matched controls [hazard ratio (HR) =41.7, 95% CI 20.0-87.0].

Conclusion

In South Korea, the DS population prevalence was 4.03 per 100,000 persons in 2015. The subjects with DS were more likely to accompany CHD and have higher mortality risk than healthy controls.

Neuroanatomical alterations in higher-order thalamic nuclei of fetuses with Down syndrome

OBJECTIVES

Down syndrome (DS) is a genetic condition characterized by cognitive disability starting from infancy. Children with DS exhibit deficits in several cognitive domains, including executive function, i.e., a set of cognitive processes that heavily depend on higher-order thalamic nuclei. The goal of this study was to establish whether executive function-related thalamic nuclei of fetuses with DS exhibit neuroanatomical alterations that may contribute to the defects in higher-order control processes seen in children with DS.

PATIENTS AND METHODS

In brain sections from fetuses with DS and control fetuses (gestational week 17-22), we evaluated the cellularity in the mediodorsal nucleus (MD), the centromedian nucleus (CM), and the parafascicular nucleus (PF) of the thalamus and the density of proliferating cells in the third ventricle.

RESULTS

We found that all three nuclei had a notably reduced cell density. This defect was associated with a reduced density of proliferating cells in the third ventricle, suggesting that the reduced cellularity in the MD, CM, and PF of fetuses with DS was due to neurogenesis impairment. The separate evaluation of projection neurons and interneurons in the MD, CM, and PF showed that in fetuses with DS the density of projection neurons was reduced, with no changes in interneuron density.

CONCLUSION

This study provides novel evidence for DS-linked cellularity alterations in the MD, CM, and PF and suggests that altered signal processing in these nuclei may be involved in the impairment in higher-order control processes observed in individuals with DS starting from infancy.

Cross-Sectional Trajectories of Mental State Language Development in Children With Down Syndrome

Purpose This article (a) examined the cross-sectional trajectories of mental state language use in children with Down syndrome (DS) and (b) identified developmental factors associated with its use. Method Forty children with DS aged 6-11 years generated stories from a wordless picture book and completed an assessment battery of other linguistic, cognitive, and social-emotional skills. Their narratives were coded for mental state language density (the proportion of utterances containing mental state references) and diversity (the number of different mental state terms used). Results The emergence of mental state language use during narrative storytelling was observed across the sample; 0%-24% of children's utterances included references to mental states, and a variety of mental state terms were produced. Cross-sectional developmental trajectory analysis revealed that expressive vocabulary and morphosyntax were significantly related to increased mental state language density and diversity. Nonverbal emotion knowledge was significantly related to greater diversity of mental state terms used. Age and nonverbal cognition were not significant factors. Conclusions This first in-depth, within-syndrome characterization of mental state language use by school-age children with DS provides an important next step for understanding mental state and narrative development in this population. By identifying skills associated with the development of mental state language, this study provides an avenue for future longitudinal research to determine causal relationships, ultimately informing intervention efforts.

How Individuals With Down Syndrome Process Faces and Words Conveying Emotions? Evidence From a Priming Paradigm

Emotion recognition from facial expressions and words conveying emotions is considered crucial for the development of interpersonal relations (Pochon and Declercq, 2013). Although Down syndrome (DS) has received growing attention in the last two decades, emotional development has remained underexplored, perhaps because of the stereotype of high sociability in persons with DS. Yet recently, there is some literature that is suggesting the existence of specific deficits in emotion recognition in DS. The current study aimed to expand our knowledge on how individuals with DS process emotion expressions from faces and words by adopting a powerful methodological paradigm, namely priming. The purpose is to analyse to what extent emotion recognition in DS can occur through different processes than in typical development. Individuals with DS (N = 20) were matched to a control group (N = 20) on vocabulary knowledge (PPTV) and non-verbal ability (Raven’s matrices). Subsequently a priming paradigm was adopted: stimuli were photos of faces with different facial expressions (happy, sad, neutral) and three words (happy, sad, neutral). On a computer screen the first item (face or word) was presented for a very short time (prime) and afterward a stimulus (face or word) appeared (target). Participants had to recognize whether the target was an emotion (sad/happy) or not (neutral). Four prime-target pairs were presented (face-word; word-face; word-word; face-word) in two conditions: congruent (same emotion prime/target) and incongruent (different emotion prime/target). The results failed to show evidence for differential processing during emotion recognition between the two groups matched for verbal and non-verbal abilities. Both groups showed a typical priming effect: In the incongruent condition, slower reaction times were recorded, in particular when the target to be recognized is the face, providing evidence that the stimuli were indeed processed. Overall, the data of the current work seem to support the idea of similar developmental trajectories in individuals with DS and TD of the same verbal and non-verbal level, at least as far as the processing of simple visual and linguistic stimuli conveying basic emotions is concerned. Results are interpreted in relation to recent finding on emotion recognition from faces and words in DS.

A Behavioural Assessment of Social Anxiety and Social Motivation in Fragile X, Cornelia de Lange and Rubinstein-Taybi Syndromes

Unique socio-behavioural phenotypes are reported for individuals with different neurodevelopmental disorders. Here, the effects of adult familiarity and nature of interaction on social anxiety and social motivation were investigated in individuals with fragile X (FXS; n = 20), Cornelia de Lange (CdLS; n = 20) and Rubinstein-Taybi (RTS; n = 20) syndromes, compared to individuals with Down syndrome (DS; n = 20). The Social Anxiety and Motivation Rating Scale was employed whilst participants completed four social tasks, each administered separately by a familiar adult, and also by an unfamiliar adult. Compared to participants with DS, those with FXS and RTS exhibited high levels of social anxiety but similar levels of social motivation. Participants with CdLS showed heightened social anxiety and reduced social motivation only during interactions with an unfamiliar adult when active participation was voluntary.

Do Infants With Down Syndrome Show an Early Receptive Language Advantage?

Purpose The study explored longitudinally the course of vocabulary and general language development in a group of infants with Down syndrome (DS) compared to a group of typically developing (TD) infants matched on nonverbal mental ability (NVMA). Method We compared the vocabulary and general language trajectories of the two groups in two ways: (a) at three time points during a 12-month period and (b) at two time points when the groups had made equal progress in NVMA (a period of 6 months for the TD infants vs. 12 months for the infants with DS). Results The TD group had overtaken the DS group on all general language and vocabulary measures by the end of the 12-month period. However, expressive communication and expressive vocabulary were developing at the same rate and level in the two groups when examined over a period in which the two groups were matched in gains in NVMA. Furthermore, the infants with DS showed a receptive language advantage over the TD group; this group's auditory comprehension and receptive vocabulary scores were superior to those of the TD group at both time points when NVMA was accounted for. Conclusion The results shed light on the widely reported discrepancy between expressive and receptive language in individuals with DS. Although infants with DS appear to be developing language skills more slowly than chronological age TD peers, when NVMA is taken into account, infants with DS do not have expressive language delays, and they seem to show a receptive language advantage.

Memorization of daily routines by children with Down syndrome assisted by a playful virtual environment

A child with Down syndrome, like any other child, may benefit from interacting with memory stimuli, but needs additional support and help. The use of special teaching methods, which add playfulness and use of the computer, can enhance the memory processes of these children. In this work, we present the virtual environment "Nossa Vida (Our Life)", which was developed to assist children with Down syndrome to memorize action sequences of their daily routine. A daily routine memorization test (DRMT), consisting of a weekly reminder of typical daily routines completed by the children and parents, was performed before (pre-test) and after (post-test) the intervention. The work involved a multidisciplinary team and assessed the effectiveness of the test performed by 30 children with Down syndrome from APAE, a special education school for children with intellectual disabilities in São Paulo, Brazil. The children were separated into two groups (Experimental - GE and Control - GC) with homogeneity and normality of the data. Two hypotheses were tested in this study: H0 and H1, where: H0 = There is no statistical difference between memorizing daily tasks between individuals with Down syndrome who used our ludic virtual environment and those who used the conventional memory method.H1 = There is a difference between the group of subjects with Down Syndrome who used our virtual game environment and the group that did not use it in relation to memorizing the daily task. This produces t = -14.98 and p <0.0001, with H1 being accepted. The results showed that the EG presented significance in relation to the CG and the evolution mean of the children in the EG was 81.82% higher. According to experts (psychologist and pedagogue) from APAE and parents, the playful activities implemented in this virtual environment have been of great interest to children, who had fun, tested hypotheses and questioned them about the sequences of actions performed in their routine daily.

Teaching Preschoolers With Down Syndrome Using Augmentative and Alternative Communication Modeling During Small Group Dialogic Reading

Purpose This study evaluated the effect of aided augmentative and alternative communication modeling (AAC-MOD) on the communication skills of children with Down syndrome (DS) during small group dialogic reading. Method Four children with DS between 3;1 and 5;3 (years;months; M = 4;5) and 5 typically developing peers between 3;5 and 5;9 (M = 4;3) participated. Effects were examined using a multiple probe across behaviors design with 4 children with DS. To simulate typical dialogic reading routines in inclusive classrooms, a strategy called Read, Ask, Answer, Prompt (Binger, Kent-Walsh, Ewing, & Taylor, 2010) was applied during the baseline and intervention sessions. Results A functional relation was demonstrated between (a) AAC-MOD and percentage of correctly identified symbols for 3 participants, (b) AAC-MOD and rate of symbolic communication for 2 participants, and (c) AAC-MOD and number of different words for 2 participants. Increases in number of multiple word combinations occurred for 2 participants. All 4 children maintained their percentage of correctly identified symbols. Increases in rate of symbolic communication did not generalize to thematic play contexts, a distal measure of response generalization. Conclusion AAC-MOD is an effective strategy for teaching target vocabulary and increasing rate of symbolic communication in young children with DS. Supplemental Material https://doi.org/10.23641/asha.10093538.

Different abilities needed at home and school: The relation between executive function and adaptive behaviour in adolescents with Down syndrome

Studies have shown that executive function abilities are related and have predictive power over adaptive behaviour in both typical and atypical populations. This study examined the relationship between executive functioning and adaptive behaviour in adolescents with Down syndrome, as it has not been studied before in this population. We propose and test a model of how each core EF (i.e., working memory, inhibition, and flexibility) contributes to each domain of AB (i.e., conceptual, social, and practical). We found that parent reported Conceptual skills were related to working memory, while teacher reported Conceptual and Practical skills were related to inhibition and flexibility. We hypothesise that these findings are related to the different requirements and expectations of the home and school environments: the more predictable home environment requires the adolescent to rely on working memory for his everyday activities, while the changing and challenging school environment requires the inhibition common behaviours and to flexibly change actions to be successful.

Early intervention physical therapy using "Parent Empowerment Program" for children with Down syndrome in Pakistan: A feasibility study

PURPOSE

The aim of this study was to evaluate the feasibility and effectiveness of the Parent Empowerment Program (PEP) to help caretakers deliver a home program to promote developmental activities and gross motor function in their children with Down syndrome.

METHODS

Parents attended a 14-month program with training sessions 1-4 times a month. Outcomes were measured using a change in the Gross Motor Function Measure (GMFM-88) at baseline and assessment one.

RESULTS

Forty-eight families participated in the PEP. Children's mean age was 16.2 ± 10.8 months. There were significant changes in GMFM-88 scores between baseline and assessment one; t (30) =-9.158, p< 0.001; 95% CI -14.6 - -22.9. Previous hospitalization significantly affected GMFM scores.

CONCLUSION

This study describes a clinically applied research that focuses on program design, development and evaluation. Findings indicate that the PEP is effective in improving gross motor function in children with Down's syndrome in Pakistan. Parents were satisfied with the program outcomes and were able to cope with the requirements at home. The PEP had favorable outcomes and may be an effective method to support PT services in resource poor countries.

Language nutrition for language health in children with disorders: a scoping review

The quantity and quality of child-directed speech-language nutrition-provided to typically-developing children is associated with language outcomes-language health. Limited information is available about child-directed speech to children at biological risk of language impairments. We conducted a scoping review on caregiver child-directed speech for children with three clinical conditions associated with language impairments-preterm birth, intellectual disability, and autism-addressing three questions: (1) How does child-directed speech to these children differ from speech to typically-developing children? (2) What are the associations between child-directed speech and child language outcomes? (3) How convincing are intervention studies that aim to improve child-directed speech and thereby facilitate children's language development? We identified 635 potential studies and reviewed 57 meeting study criteria. Child-directed speech to children with all conditions was comparable to speech to language-matched children; caregivers were more directive toward children with disorders. Most associations between child-directed speech and outcomes were positive. However, several interventions had minimal effects on child language. Trials with large samples, intensive interventions, and multiple data sources are needed to evaluate child-directed speech as a means to prevent language impairment. Clinicians should counsel caregivers to use high quality child-directed speech and responsive communication styles with children with these conditions.

Aberrant Oligodendrogenesis in Down Syndrome: Shift in Gliogenesis?

Down syndrome (DS), or trisomy 21, is the most prevalent chromosomal anomaly accounting for cognitive impairment and intellectual disability (ID). Neuropathological changes of DS brains are characterized by a reduction in the number of neurons and oligodendrocytes, accompanied by hypomyelination and astrogliosis. Recent studies mainly focused on neuronal development in DS, but underestimated the role of glial cells as pathogenic players. Aberrant or impaired differentiation within the oligodendroglial lineage and altered white matter functionality are thought to contribute to central nervous system (CNS) malformations. Given that white matter, comprised of oligodendrocytes and their myelin sheaths, is vital for higher brain function, gathering knowledge about pathways and modulators challenging oligodendrogenesis and cell lineages within DS is essential. This review article discusses to what degree DS-related effects on oligodendroglial cells have been described and presents collected evidence regarding induced cell-fate switches, thereby resulting in an enhanced generation of astrocytes. Moreover, alterations in white matter formation observed in mouse and human post-mortem brains are described. Finally, the rationale for a better understanding of pathways and modulators responsible for the glial cell imbalance as a possible source for future therapeutic interventions is given based on current experience on pro-oligodendroglial treatment approaches developed for demyelinating diseases, such as multiple sclerosis.

Neuronal Cell-Intrinsic Defects in Mouse Models of Down Syndrome

Down Syndrome (DS) is the most common genetic disorder associated with intellectual disability (ID). Excitatory neurons of DS patients and mouse models show decreased size of dendritic field and reduction of spine density. Whether these defects are caused by cell autonomous alterations or by abnormal multicellular circuitry is still unknown. In this work, we explored this issue by culturing cortical neurons obtained from two mouse models of DS: the widely used Ts65Dn and the less characterized Ts2Cje. We observed that, in the in vitro conditions, axon specification and elongation, as well as dendritogenesis, take place without evident abnormalities, indicating that the initial phases of neuronal differentiation do not suffer from the presence of an imbalanced genetic dosage. Conversely, our analysis highlighted differences between trisomic and euploid neurons in terms of reduction of spine density, in accordance with in vivo data obtained by other groups, proposing the presence of a cell-intrinsic malfunction. This work suggests that the characteristic morphological defects of DS neurons are likely to be caused by the possible combination of cell-intrinsic defects together with cell-extrinsic cues. Additionally, our data support the possibility of using the more sustainable line Ts2Cje as a standard model for the study of DS.

What are the benefits of having a village? Effects of allomaternal care on communicative skills in early infancy

This study investigates whether exposure to allomaternal care (AMC-care for infants from individuals other than the mother) improves rates of communicative behaviors during late infancy by providing more opportunities to practice communicating with varied caregivers. Data were collected from 102 typically-developing infants aged 13-18 months and their mothers. AMC variables were collected using a current care questionnaire, structured 14-day diary, and longitudinal interview. Communicative behaviors were assessed through post hoc microcoding of in-lab administrations of the Early Social Communication Scales (ESCS), as well as additional microcoding of the Bayley III Screening Cognitive Subtest. Demographic covariates were also included. For each communicative behavior, backward model selection was used to determine the best fitting linear regression model. Results suggested that rates of turn-taking decreased with Household AMC (p < 0.008), but increased with two or more siblings present at home (p < 0.01). Conversely, rates of spontaneous giving increased with Household AMC (p < 0.003) regardless of the presence of siblings. Notably, exposure to more AMC was neither helpful nor harmful for many of the tested communicative behaviors, although the number of siblings present was significantly related to rates of following commands, as well as pointing and reaching. Ultimately, this study suggests that household level experiences with AMC, rather than formalized care, impact the development of some communicative behaviors during late infancy.

Assessing general cognitive and adaptive abilities in adults with Down syndrome: a systematic review

BACKGROUND

Measures of general cognitive and adaptive ability in adults with Down syndrome (DS) used by previous studies vary substantially. This review summarises the different ability measures used previously, focusing on tests of intelligence quotient (IQ) and adaptive behaviour (AB), and where possible examines floor effects and differences between DS subpopulations. We aimed to use information regarding existing measures to provide recommendations for individual researchers and the DS research community.

RESULTS

Nineteen studies reporting IQ test data met inclusion for this review, with 17 different IQ tests used. Twelve of these IQ tests were used in only one study while five were used in two different studies. Eleven studies reporting AB test data met inclusion for this review, with seven different AB tests used. The only AB scales to be used by more than one study were the Vineland Adaptive Behaviour Scale (VABS; used by three studies) and the Vineland Adaptive Behavior Scale 2nd Edition (VABS-II; used by two studies). A variety of additional factors were identified which make comparison of test scores between studies problematic, including different score types provided between studies (e.g. raw scores compared to age-equivalent scores) and different participant inclusion criteria (e.g. whether individuals with cognitive decline were excluded). Floor effects were common for IQ tests (particularly for standardised test scores). Data exists to suggest that floor effects may be minimised by the use of raw test scores rather than standardised test scores. Raw scores may, therefore, be particularly useful in longitudinal studies to track change in cognitive ability over time.

CONCLUSIONS

Studies assessing general ability in adults with DS are likely to benefit from the use of both IQ and AB scales. The DS research community may benefit from the development of reporting standards for IQ and AB data, and from the sharing of raw study data enabling further in-depth investigation of issues highlighted by this review.

Views of professionals about the educational needs of children with neurodevelopmental disorders

BACKGROUND

Professionals play a key role in supporting children with special educational needs in schools. However, the views of those working with neurodevelopmental disorders are less known.

AIMS

This study examined the views of professionals (including teachers, teaching assistants, educational psychologists, speech and language therapists, physio and occupational therapists etc.) working with children with Williams Syndrome (WS), Down Syndrome (DS) or with Autism Spectrum Disorders (ASD) in terms of how informed professionals are about the disorder and their views about the type of support these children need to be receiving.

METHODS AND PROCEDURES

Professionals working with 77 children with ASD, 26 with DS and 38 with WS completed an online questionnaire.

OUTCOMES AND RESULTS

Professionals in all three groups highlighted relevant areas of difficulty for these children, but they did not recognise some of the less phenotypical difficulties that children with a specific disorder may experience. In addition, there was a disconnect between the difficulties identified by the professionals and the type of specialist support that may be necessary.

CONCLUSIONS AND IMPLICATIONS

Although professionals have a lot of knowledge about the specific neurodevelopmental disorders, further evidence-based training would allow more effective support for children with neurodevelopmental disorders in the classroom but also equip professionals better and raise their confidence in meeting these children's needs.

New approaches to studying early brain development in Down syndrome

Down syndrome is the most common genetic developmental disorder in humans and is caused by partial or complete triplication of human chromosome 21 (trisomy 21). It is a complex condition which results in multiple lifelong health problems, including varying degrees of intellectual disability and delays in speech, memory, and learning. As both length and quality of life are improving for individuals with Down syndrome, attention is now being directed to understanding and potentially treating the associated cognitive difficulties and their underlying biological substrates. These have included imaging and postmortem studies which have identified decreased regional brain volumes and histological anomalies that accompany early onset dementia. In addition, advances in genome-wide analysis and Down syndrome mouse models are providing valuable insight into potential targets for intervention that could improve neurogenesis and long-term cognition. As little is known about early brain development in human Down syndrome, we review recent advances in magnetic resonance imaging that allow non-invasive visualization of brain macro- and microstructure, even in utero. It is hoped that together these advances may enable Down syndrome to become one of the first genetic disorders to be targeted by antenatal treatments designed to 'normalize' brain development. WHAT THIS PAPER ADDS: Magnetic resonance imaging can provide non-invasive characterization of early brain development in Down syndrome. Down syndrome mouse models enable study of underlying pathology and potential intervention strategies. Potential therapies could modify brain structure and improve early cognitive levels. Down syndrome may be the first genetic disorder to have targeted therapies which alter antenatal brain development.

Learning Prosody in a Video Game-Based Learning Approach

With the growth in popularity of video games in our society many teachers have worked to incorporate gaming into their classroom. It is generally agreed that by adding something fun to the learning process students become more engaged and, consequently, retain more knowledge. However, although the characteristics of video games facilitate the dynamics of the educational process it is necessary to plan a pedagogical project that includes delimitation of learning goals and profile of the addressees, the conditions of application of the educational project, and the methodologies of evaluation of the learning progress. This is how we can make a real difference between gamification and video game based learning. The paper addresses the design of an educational resource for special education needs (SEN) students that aims to help teach communicative skills related to prosody. The technological choices made to support the pedagogic issues that underlie the educational product, the strategies to convert learning content into playful material, and the methodology to obtain measures of its playability and effectiveness are described. The results of the motivation test certified that the video game is useful in encouraging the users to exercise their voice and the indicators of the degree of achievement of the learning goals serve to identify the most affected prosodic skills.

More severe intellectual disability found in teenagers compared to younger children with Down syndrome

AIM

We investigated the severities and profiles of intellectual disability (ID) in a population-based group of children with Down syndrome and related the findings to coexisting autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD).

METHODS

There were about 100 children with Down syndrome living in Uppsala County, Sweden, at the time of the study who all received medical services from the same specialist outpatient clinic. The 60 children (68% male) were aged 5-17 years at inclusion: 41 were assessed within the study and 19 had test results from previous assessments, performed within three years before inclusion. We compared two age groups: 5-12 and 13-18 years old.

RESULTS

Of the 60 children, 49 were assessed with a cognitive test and the 11 children who could not participate in formal tests had clinical assessments. Mild ID was found in 9% of the older children and in 35% of the younger children. Severe ID was found in 91% of the older children and 65% of the younger children. Verbal and nonverbal domains did not differ.

CONCLUSION

Intellectual level was lower in the older children and patients with Down syndrome need to be followed during childhood with regard to their ID levels.

Spoken fictional narrative and literacy skills of children with Down syndrome

BACKGROUND

Children with Down syndrome (DS) exhibit below average nonverbal intelligence and impaired language skills; however, their spoken narrative production is a relative strength.

AIMS

We examined expressive language skills produced during fictional narrative retells and analyzed the unique contribution of expressive language skills to word-level reading and reading comprehension of children with DS.

METHODS AND PROCEDURES

The microstructure and macrostructure of fifteen, 8- to 18-year-old children with DS's narrative retells were analyzed. Receptive vocabulary, word-level reading, and reading comprehension also were measured.

RESULTS

Narrative microstructure analyses revealed restricted syntactic and semantic diversity. Further analyses of sentence complexity revealed that children with DS predominately produced prepositional phrases and produced more verbs than nouns. Narrative macrostructure analysis revealed participants use of episodic components; however, their stories did not include mental state references. Narrative microstructure contributed unique variance to word-level reading, whereas narrative macrostructure contributed unique variance to word-level reading and reading comprehension. Additionally, strong correlations were found between narrative skills and literacy skills.

CONCLUSIONS AND IMPLICATIONS

Findings from this study support the use of narrative microstructure and macrostructure analyses as a valuable clinical tool to guide assessment and intervention planning for school-aged children with DS.

Adaptive Behavior and Intelligence in Adolescents With Down Syndrome: An Exploratory Investigation

Down syndrome (DS) is characterized by difficulties in both intellectual functioning and adaptive behavior. These sets of abilities are considered as separate but related domains with small to moderate correlations. The main objective of this study was to explore the relationship of intellectual functioning and adaptive behavior in adolescents with DS because previous studies have shown different relationship patterns between these constructs across other syndromes. Fifty-three adolescents with DS were assessed regarding their intellectual functioning whereas adaptive behavior was reported by parents and teachers. Participants showed a better performance on verbal than nonverbal tasks when assessing intellectual functioning, contrary to previous findings. Regarding adaptive behavior, higher social skills were reported than conceptual and practical skills. Intellectual functioning and adaptive behavior showed a medium correlation, consistent with observations in typical population. These results support the exploration of the variability across the DS phenotype.