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Background: Spatial knowledge about an environment is an important determinant of ability to move effectively within it and of personal autonomy. Individuals with Down's syndrome (DS) have difficulty managing configural visuospatial information. Method: Twenty-nine individuals with DS and 29 typically developing (TD) children, matched for mental age, learned about environments through virtual exploration using a route or survey view. A sketch map of the environment was or was not presented before exploration. Then the acquisition of configural knowledge (landmark locations) and route retracing were tested. Results: Individuals with DS were able to acquire configural knowledge through virtual exploration in all presentation conditions, and generally performed no worse than matched TD children. However, they were not able to benefit from the conditions that facilitated acquisition of configural knowledge in TD children, that is, seeing a sketch map before exploring and exploring in survey (rather than route) view. As regards route retracing, individuals with DS paused more often than controls and tended to travel longer paths, which made them slower overall. Conclusions: DS reduces children's ability to benefit from additional survey information and may be related to difficulty in elaborating configural/simultaneous information.

Background: Recent studies have shown that individuals with Down syndrome (DS) are poorer than controls in performing verbal and visuospatial dual tasks. The present study aims at better investigating the dual task deficit in working memory in individuals with DS. Method: Forty-five individuals with DS and 45 typically developing children matched for verbal mental age completed a series of verbal and visuospatial working memory tasks, involving conditions that either required the combination of two tasks in the same modality (verbal or visual) or of cross-modality pairs of tasks. Results and conclusions: Two distinct deficits were found in individuals with DS: impairment in verbal tasks and further impairment in all dual task conditions. The results confirm the hypothesis of a central executive impairment in individuals with DS.

Background: Recent studies have demonstrated that individuals with Down syndrome (DS) are poorer than controls in spatial-simultaneous tasks, but not in spatial-sequential tasks. To explain this finding, it has been suggested that the simultaneous visuo-spatial working memory deficit of individuals with DS could be due to the request for processing more than one item at a time. The present study examines the possibility of reducing the difficulties encountered by DS individuals on spatial-simultaneous tasks by proposing a task that uses structured material. Method: Two tasks were administered to 20 children and adolescents with DS, and 20 controls matched for verbal mental age. The tasks involved memorising and recalling filled-cell positions in a series of matrices in which an increasing number of cells (1-7) were filled. In the structured condition the filled cells were displayed to form a pattern, whereas in the random condition they were randomly arranged. Results and Conclusions: Results showed that individuals with DS are able to take advantage of structured material for raising their performance, but to a less extent than typically developing children. (Contains 2 figures, 2 tables and 2 footnotes.)

Background: The present work is aimed at analysing executive function (EF) in adolescents with Down Syndrome (DS). So far, EF has been analysed mainly in adults with DS, showing a pattern of impairment. However, less is known about children and adolescents with this syndrome. Studying adolescents with DS might help us better understand whether performances on EF tasks of individuals with DS are determined by age or by Alzheimer disease, as some studies suggest, or whether their performances are directly related to DS cognitive profile. Method: A battery of EF tasks assessing set shifting, planning/problem-solving, working memory, inhibition/perseveration and fluency, as well as a tasks assessing sustained attention has been administered to a group of 15 adolescents with DS and 15 typically developing children matched for mental age. All EF tasks were selected from previous studies with individuals with intellectual disabilities or from developmental literature and are thought to be useful for the samples considered. Results: The present results revealed that the group of individuals with DS performed at a significantly lower level on tasks assessing set shifting, planning/problem-solving, working memory and inhibition/perseveration, but not on the tasks assessing fluency. In addition, individuals with DS demonstrated a greater number of errors and less strategy use for the sustained attention task. Conclusions: The results suggest a broad impairment in EF in adolescents with DS, and are consistent with several similar studies conducted with adults with DS. We assume that EF deficit is a characteristic of DS.

Background: Recent studies have demonstrated that individuals with Down syndrome (DS) present both central and verbal working memory deficits compared with controls matched for mental age, whereas evidence on visuospatial working memory (VSWM) has remained ambiguous. The present paper uses a battery of VSWM tasks to test the hypothesis that individuals with DS can also encounter specific difficulties in VSWM. Method: Four tasks were administered to 34 children and adolescents with DS and 34 controls matched for verbal mental age. In two of these tasks, participants had to remember a series of locations sequentially presented on a matrix (spatial-sequential WM); in another two, they had to remember locations simultaneously presented (spatial-simultaneous WM). Results and Conclusions: Results showed that individuals with DS are poorer than controls in the spatial-simultaneous tasks, but not in the spatial-sequential tasks. These findings were not due to a difference in speed of visuospatial processing. In fact, when performances of the two groups in VSWM were compared using speed measures as covariates, differences between groups remained. It is suggested that the simultaneous VSWM deficit of individuals with DS could be due to the request for processing more than one item at a time.

This editorial presents an introduction to and an overview of the current JIDR special issue on "Executive Function in Intellectual Disability." The articles included in this special issue provide a contemporary, in depth exploration of questions regarding the nature of EF in individuals with ID. Topics include the emergence of EF during early childhood in ID‐related conditions, the influence of EF on other domains of development, and the relationship between EF and adaptation throughout the lifespan. This editorial synthesizes the findings presented in this special issue and identifies methodological challenges that researchers will continue to face in future investigations of this important area. [ABSTRACT FROM AUTHOR]

Background: Previous research has explored executive functions (EFs) and adaptive behaviour in children and adolescents with Down syndrome (DS), but there is a paucity of research on the relationship between the two in this population. This study aims to shed light on the profile of EFs and adaptive behaviour in DS, exploring the differences by age and investigating the relationship between these two domains. Method: Parents/caregivers of 100 individuals with DS from 3 to 16 years old participated in the study. The sample was divided into preschoolers (3–6.11 years old) and school‐age children (7–16 years old). Parents/caregivers completed either the Preschool Version of the Behaviour Rating Inventory of Executive Function (for children 2–6.11 years old) or the Second Edition of the same Inventory (for individuals 7 + years old). Adaptive behaviour was assessed with the Vineland Adaptive Behaviour Scale – Interview, Second Edition. Results: Findings suggest that individuals with DS have overall difficulties, but also patterns of strength and weakness in their EFs and adaptive behaviour. The preschool‐age and school‐age children's EF profiles differed slightly. While both age groups showed Emotional Control as a relative strength and Working Memory as a weakness, the school‐age group revealed further weaknesses in Shift and Plan/Organise. As concerns adaptive behaviour, the profiles were similar in the two age groups, with Socialisation as a strength, and Communication and Daily Living Skills as weaknesses, but with a tendency for preschoolers to obtain intermediate scores for the latter. When the relationship between EFs and adaptive behaviour was explored, Working Memory predicted Communication in the younger group, while in the older group the predictors varied, depending on the adaptive domains: Working Memory was a predictor of Communication, Inhibit of Daily Living Skills, and Inhibit and Shift of Socialisation. Conclusion: As well as elucidating the EF profiles and adaptive behaviour in individuals with DS by age, this study points to the role of EFs in adaptive functioning, providing important information for targeted interventions. [ABSTRACT FROM AUTHOR]

Background: Working memory (WM) is generally considered an area of weakness in the cognitive profile associated with Down syndrome (DS). The great majority of studies explored WM in this population through a comparison with typical development (TD) on the basis of mental age or developmental level. However, it is also relevant to understand how these skills develop and whether such development could be more related to chronological or developmental level. In the present study, we explored cross‐sectional developmental trajectories of spatial‐sequential and spatial‐simultaneous WM in individuals with DS across chronological age and developmental level. Typically developing children (TD) of similar mental age were also included as a comparison group. Methods: Eighty‐four individuals with DS (aged between 7 and 30 years) and 327 children with TD (aged between 4 and 8 years) were administered with tasks to assess spatial‐sequential and spatial‐simultaneous WM, together with tasks to assess both general verbal and spatial developmental levels. Results and conclusion: Performance in spatial‐simultaneous WM task was lower compared with spatial‐sequential WM task in both groups. In the case of individuals with DS, the developmental trajectories of chronological age are better described through a segmented model showing increased performance until approximately 13 years of age, followed by a rather flat progress. In the case of TD children, developmental trajectories are better described through a linear model in the spatial‐simultaneous WM task when chronological age is considered; in the spatial‐sequential WM, the increase in performance with age was however characterised by a discontinuity at age 6. The increase in performance followed a linear pattern in both groups (DS and TD) without substantial differences between the types of measure used (verbal vs. spatial) when the developmental level is considered. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to assess the reliability and validity of the Italian translation of the Unhelpful Thoughts and Beliefs about Stuttering (UTBAS) scales for adults who stutter, as there are no assessment tools currently available in Italy. The UTBAS scales provide a comprehensive stuttering-specific measure of the unhelpful thoughts and beliefs that can be used to screen for indicators of social anxiety in adults who stutter. Additionally, the UTBAS scales also allow the identification of negative thoughts and beliefs that negatively impact speech treatment outcomes., Method: The translation of the UTBAS scales into Italian (UTBAS-ITA) was completed using the forward-backward translation process and it was administered to 98 adults who stutter (AWS) and 98 adults who do not stutter (AWNS). Both groups were matched for gender and age. We also administered the UTBAS-ITA to 76 AWS a second time within a two-week interval to assess test-retest reliability. Additionally, we administered the State-Trait Anxiety Inventory and the Fear of Negative Evaluation Scale to 20 AWS to assess concurrent validity., Results: The UTBAS-ITA showed good power of discrimination between AWS and AWNS, high internal validity, high internal consistency, good construct validity, and good test-retest reliability., Conclusion: Since there is a scarcity of clinical assessment tools for adults who stutter in Italy, the UTBAS-ITA could serve as an assessment tool and outcome measure for clinical and research environments., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Parent-mediated intervention (PMI) is a potentially scalable approach for tailored interventions in neurogenetic conditions like Down syndrome (DS). Because PMIs require ongoing parent engagement, they must be developed in alignment with the needs of intended users. The present study examined caregiver opinions and preferences to inform the development of syndrome-informed interventions for children with DS., Method: Parents of children with DS (n = 34) participated in focus groups discussing PMI. Interviews were transcribed and a thematic analysis was applied to code the data., Results: Three themes were identified: advantages of PMI, disadvantages of PMI and preferred features of PMI. To align with parent preferences, future PMIs for children with DS should require a brief time commitment, blend intervention activities into daily routines and include family members in activities., Conclusions: Findings have implications for developing novel interventions to support early development in children with DS and other neurogenetic conditions., (© 2024 The Author(s). Journal of Applied Research in Intellectual Disabilities published by John Wiley & Sons Ltd.)

Impaired numerosity perception in developmental dyscalculia (low "number acuity") has been interpreted as evidence of reduced representational precision in the neurocognitive system supporting non-symbolic number sense. However, recent studies suggest that poor numerosity judgments might stem from stronger interference from non-numerical visual information, in line with alternative accounts that highlight impairments in executive functions and visuospatial abilities in the etiology of dyscalculia. To resolve this debate, we used a psychophysical method designed to disentangle the contribution of numerical and non-numerical features to explicit numerosity judgments in a dot comparison task and we assessed the relative saliency of numerosity in a spontaneous categorization task. Children with dyscalculia were compared to control children with average mathematical skills matched for age, IQ, and visuospatial memory. In the comparison task, the lower accuracy of dyscalculics compared to controls was linked to weaker encoding of numerosity, but not to the strength of non-numerical biases. Similarly, in the spontaneous categorization task, children with dyscalculia showed a weaker number-based categorization compared to the control group, with no evidence of a stronger influence of non-numerical information on category choice. Simulations with a neurocomputational model of numerosity perception showed that the reduction of representational resources affected the progressive refinement of number acuity, with little effect on non-numerical bias in numerosity judgments. Together, these results suggest that impaired numerosity perception in dyscalculia cannot be explained by increased interference from non-numerical visual cues, thereby supporting the hypothesis of a core number sense deficit. RESEARCH HIGHLIGHTS: A strongly debated issue is whether impaired numerosity perception in dyscalculia stems from a deficit in number sense or from poor executive and visuospatial functions. Dyscalculic children show reduced precision in visual numerosity judgments and weaker number-based spontaneous categorization, but no increasing reliance on continuous visual properties. Simulations with deep neural networks demonstrate that reduced neural/computational resources affect the developmental trajectory of number acuity and account for impaired numerosity judgments. Our findings show that weaker number acuity in developmental dyscalculia is not necessarily related to increased interference from non-numerical visual cues., (© 2024 The Author(s). Developmental Science published by John Wiley & Sons Ltd.)

Background: Persons with Down syndrome (DS) reveal adaptive functioning (AF) difficulties. Studies on AF in DS have focused mainly on describing the profile (i.e., strengths in socialization, and weaknesses in communication), while less is known about age-related differences. This study aimed to elucidate how AF changes with age in children and adolescents with DS, taking a cross-sectional developmental trajectory approach. Moreover, the contribution of both chronological age (CA) and mental age (MA) on AF development was explored., Method: This study involved 115 children and adolescents (between 3 and 16 years old) with DS. Parents were interviewed about their children's AF on communication, daily living and socialization skills. Children and adolescents with DS were assessed on their developmental level., Results: While participants' standard scores on AF decreased linearly over time, their age-equivalent scores increased with linear or segmented patterns, depending on the skill considered. CA and MA were related to daily living skills and socialization to much the same degree, while MA correlated more strongly than CA with communication., Conclusion: This study contributes to the understanding of how AF develops in children and adolescents with DS, showing that CA and MA both contribute to shaping the skills involved., (Copyright © 2023. Published by Elsevier Ltd.)

Down syndrome (DS) or trisomy 21 is the most common genetic cause of intellectual disability (ID), but a pathogenic mechanism has not been identified yet. Studying a complex and not monogenic condition such as DS, a clear correlation between cause and effect might be difficult to find through classical analysis methods, thus different approaches need to be used. The increased availability of big data has made the use of artificial intelligence (AI) and in particular machine learning (ML) in the medical field possible. The purpose of this work is the application of ML techniques to provide an analysis of clinical records obtained from subjects with DS and study their association with ID. We have applied two tree-based ML models (random forest and gradient boosting machine) to the research question: how to identify key features likely associated with ID in DS. We analyzed 109 features (or variables) in 106 DS subjects. The outcome of the analysis was the age equivalent (AE) score as indicator of intellectual functioning, impaired in ID. We applied several methods to configure the models: feature selection through Boruta framework to minimize random correlation; data augmentation to overcome the issue of a small dataset; age effect mitigation to take into account the chronological age of the subjects. The results show that ML algorithms can be applied with good accuracy to identify variables likely involved in cognitive impairment in DS. In particular, we show how random forest and gradient boosting machine produce results with low error (MSE <0.12) and an acceptable R 2 (0.70 and 0.93). Interestingly, the ranking of the variables point to several features of interest related to hearing, gastrointestinal alterations, thyroid state, immune system and vitamin B12 that can be considered with particular attention for improving care pathways for people with DS. In conclusion, ML-based model may assist researchers in identifying key features likely correlated with ID in DS, and ultimately, may improve research efforts focused on the identification of possible therapeutic targets and new care pathways. We believe this study can be the basis for further testing/validating of our algorithms with multiple and larger datasets., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

There is a host of research on the structure of working memory (WM) and its relationship with intelligence in adults, but only a few studies have involved children. In this paper, several different WM models were tested on 170 Japanese school children (from 7 years and 5 months to 11 years and 6 months). Results showed that a model distinguishing between modalities (i.e., verbal and spatial WM) fitted the data well and was therefore selected. Notably, a bi-factor model distinguishing between modalities, but also including a common WM factor, presented with a very good fit, but was less parsimonious. Subsequently, we tested the predictive power of the verbal and spatial WM factors on fluid and crystallized intelligence. Results indicated that the shared contribution of WM explained the largest portion of variance of fluid intelligence, with verbal and spatial WM independently explaining a residual portion of the variance. Concerning crystallized intelligence, however, verbal WM explained the largest portion of the variance, with the joint contribution of verbal and spatial WM explaining the residual part. The distinction between verbal and spatial WM could be important in clinical settings (e.g., children with atypical development might struggle selectively on some WM components) and in school settings (e.g., verbal and spatial WM might be differently implicated in mathematical achievement).

The purpose of this study was to identify developmental profiles associated with autism spectrum disorder (ASD) and global developmental delay (DD) in pre-school aged Italian children. Developmental profiles were evaluated by means of a standardized tool widely used for the assessment of psychomotor development in early childhood, the Griffiths III scales, recently adapted and standardized for the Italian population. Specifically, we compared the Griffiths III profiles of children with ASD and DD (ASD + DD) with those of children with DD alone. Moreover, we inspected the psychometric function of single items by comparing children with ASD + DD and children with DD with typically developing (TD) children from the Griffiths III normative sample. In this way, we aimed to isolate the effects of each diagnostic class on psychomotor abilities and on the psychometric function of single items. The ASD + DD and DD groups were found to share the presence of lower age equivalent scores relative to their chronological age in all the developmental domains considered: Foundations of Learning, Language and Communication, Eye and Hand Coordination, Personal-Social-Emotional and Gross Motor Skills. However, the DD group displayed a homogeneous profile with similar levels of delay in all developmental domains, while children with ASD + DD exhibited relative weaknesses in the Language and Communication and Personal-Social-Emotional scales. The analysis of the psychometric function drawn for each item has confirmed different profiles in social-communicative and non-verbal items between the two diagnostic groups and in relation to TD normative sample. The Griffiths III is a valid psychometric tool for identifying atypical developmental profiles and its use may be recommended during the diagnostic process of ASD and DD, to detect specific strengths and weaknesses and guide person-centered treatment., (© 2023 The Authors. Autism Research published by International Society for Autism Research and Wiley Periodicals LLC.)