A meta-analysis of the executive function components inhibition, shifting, and attention in intellectual disabilities

Do Motor-Cognitive and Motor-Motor Dual-Task Training Differently Affect Dual-Task Interference in Individuals With Intellectual Disability?

This study explored the effect of different dual-task (DT) training programs on DT interference in adults with intellectual disability. Center-of-pressure (CoP) mean velocity in single-task (ST) and cognitive-DT conditions and the Timed Up-and-Go Test (TUGT) during ST, cognitive-DT, and motor-DT conditions were assessed before and after intervention in a cognitive-motor training group, a motor-motor training group, and a control group. Before training, CoP mean velocity and TUGT time increased (p < .001) in DT compared with the ST condition. After training, the CoP mean velocity values remained unchanged (p = .07) in DT compared with the ST condition among the cognitive-motor training group. Furthermore, compared with the ST condition, no increase (p = 1) was reported in the TUGT time during the cognitive-DT condition for the cognitive-motor training group and during the motor-DT for the motor-motor training group (p = .12). The effect of DT training on DT interference depends on the training modality.

Effects of a dual-task activity on gait parameters of people with and without intellectual disabilities

BACKGROUND

The main objective of this study was to evaluate gait parameters in people with intellectual disability (ID) and without intellectual disability (WID) in two different walking conditions [single task vs. dual task (DT)]. A secondary aim was to evaluate the dual-task cost (DTC) that the DT causes in each group.

METHODS

A total of 119 participants joined in this study: 56 ID (30 men) and 63 WID (30 men). The OptoGait system was used to assess gait. In addition, Witty photocells were added to assess gait under the DT condition.

RESULTS

Single support time was lower for participants with ID (P < 0.01), while double support time was higher (P < 0.05). All coefficients of variation for gait parameters were higher in participants with ID. Additionally, changes in gait were observed in both groups during the DT condition compared with the single-task condition. These changes were larger for participants with ID in step length, double support time and gait speed (P < 0.001), resulting in a higher DTC in these variables in the ID group (P < 0.01).

CONCLUSIONS

Both groups reduced gait performance in the DT condition. However, greater gait variability occurred in the ID group. In addition, DTC was higher for the ID group in all variables analysed. Therefore, people with ID show worse gait performance during a DT than people WID.

Effects of a physical education intervention on attention and inhibitory control in Ecuadorian children with intellectual disabilities

Background: Studies on physical activity interventions indicated a facilitative effect on cognitive performance in persons with intellectual disabilities; however, research is scarce, especially in low/middle-income countries. Aim: We explored the effects of a 6-week enriched physical education program on inhibitory control and attention functions in Ecuadorian children with intellectual disabilities. Methods: Thirty children with mild intellectual disabilities (10-14 years old) were randomly assigned to an intervention or control group. Before and after the intervention, attention and inhibitory control were measured using computer-based nonverbal tasks. Results: The findings showed significantly more accurate and faster responses in the vigilance task in the intervention group than in the controls. There were no significant intervention-related changes in inhibitory control; however, there were more prominent accuracy tendencies toward improvement in the intervention group. Conclusions: Results provide evidence of the potential of physical activity programs to enhance attention in this population, which could serve as a mediator for inhibitory control.

Associations Between Executive Functioning, Behavioral Functioning, and Adaptive Functioning Difficulties in Wiedemann-Steiner Syndrome

OBJECTIVES

Wiedemann-Steiner syndrome (WSS) is a neurogenetic disorder caused by heterozygous variants in KMT2A. Recent investigations suggest increased anxiety and behavior regulation challenges among those with WSS although the neurobehavioral phenotype remains largely unknown. This study aims to examine the pattern of and associations between executive functioning (EF) and behavior functioning among those with WSS.

METHOD

This study involved utilizing caregiver-report inventories (Behavior Rating Inventory of Executive Function 2nd Edition, BRIEF-2; Adaptive Behavior Assessment 3rd Edition, ABAS-3; Strengths and Difficulties Questionnaire, SDQ) to assess day-to-day behavior functioning among those with WSS (N = 24; mean age = 10.68 years, SD = 3.19). Frequency of clinical elevations in daily difficulties in EF, adaptive behaviors, and behavior regulation were reported. Correlations and hierarchical linear regressions were used to determine the relationships between EF with behavior and adaptive functioning.

RESULTS

Out of our sample, 63% met clinical levels of executive functioning difficulties on the BRIEF-2, and 75% with Hyperactivity and 54% with Emotional Problems on the SDQ. In addition, 33% were rated >2 SD below the normative mean in overall adaptive functioning on the ABAS-3. Elevated ratings in BRIEF-2 Shift, reflective of challenges with mental flexibility, predicted more Emotional Problems and accounted for 33.5% of its variance. More difficulties in Emotional Control were related to greater adaptive deficits, accounting for 33.3% of its variance.

CONCLUSIONS

Those with WSS are at risk for EF deficits, hyperactivity, and emotional dysregulation. EF correlates with adaptive and affective behaviors, highlighting the promise of behavioral interventions to target cognitive flexibility, emotional awareness, and reactivity in this population.

An Individual Music Intervention for Adults With Intellectual Disabilities and Challenging Behavior: Protocol for a Randomized Controlled Trial

BACKGROUND

Individuals with intellectual disabilities (ID) are more likely to have problems with executive functioning (EF) and challenging behavior (CB), which are negatively linked to well-being. Among clinical populations, music interventions have been shown to improve various outcome measures, such as CB and EF. Until now, no randomized controlled trials (RCTs) have been conducted to examine the effectiveness of an individual music intervention for adults with ID and CB.

OBJECTIVE

The study aims to identify the effect and feasibility of an individual music intervention compared with care-as-usual for people with ID and CB.

METHODS

In this study, a 2-group RCT with a pretest, posttest, and follow-up assessment after 8 weeks is presented. Participants of the music intervention condition will receive 16 individual music sessions within 8 to 10 weeks. The music intervention will be guided by a manual for music workers, in which every session will have a different focus (introduction, emotions, different EF, and end performance). Participants receiving care as usual will function as a control group. After the research is finished, they will be offered a budget, which they can spend on musical activities or musical instruments as they wish. Assessments will include caregiver rating scales and self-report questionnaires and tests, which will assess outcome measures of CB, well-being, depression, anxiety, self-esteem, and 4 domains of EF. A process evaluation will be conducted after the completion of the study, which entails the analysis of data on multiple aspects of the intervention and the study overall.

RESULTS

Enrollment commenced in July 2021, and data collection ended in May 2023. A total of 97 participants were recruited, with 44 participants allocated to the intervention group and 53 allocated to the control group. Data will be analyzed after this protocol has been accepted for publication.

CONCLUSIONS

Because there are currently no published RCTs of an individual music intervention for adults with ID and CB, this study will provide insight into the effectiveness and experiences of an individual music intervention for this target group.

TRIAL REGISTRATION

International Clinical Trials Registry Platform NL8482; http://tinyurl.com/4565s5pd.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/52497.

Expanding considerations for treating avoidant/restrictive food intake disorder at a higher level of care

Existing descriptions of the treatment of avoidant/restrictive food intake disorder (ARFID) at higher levels of care (HLOC) for eating disorders are limited, despite HLOC settings frequently serving patients with ARFID. The purpose of this commentary is to expand on the preliminary literature that describes pediatric ARFID treatment at HLOC by describing two specific components of our approach to treating pediatric ARFID that may not yet have traction in the current literature. Specifically, we highlight the utility of (1) treatment accommodations that appropriately account for patients' neurodevelopmental needs (e.g., executive functioning, sensory processing) and (2) the adjunctive use of Dialectical Behavior Therapy (DBT) elements within family-based pediatric ARFID treatment. We also describe necessary future directions for research in these domains to clarify if incorporating these considerations and approaches into pediatric ARFID treatment at HLOC does indeed improve treatment outcomes.

The associations among executive planning, self-determination, and quality of life in adolescents with intellectual disability

BACKGROUND

Skills such as planning and problem solving that are required in self-determination can be cognitively demanding. It has not yet been examined whether executive functions and intelligence are associated with levels of self-determination in individuals with intellectual disability (ID), and how that is related to quality of life (QoL). This study examined the associations among executive functions, intelligence, self-determination, and QoL in adolescents with ID.

METHODS

Seventy-nine adolescents aged between 17 and 20 years with mild ID participated in the study. Executive functions were assessed by experimental tasks. Non-verbal IQ and survey data regarding QoL and self-determination capacity were collected from the participants.

RESULTS

In a regression model with QoL as the dependent variable, only executive planning and self-determination capacity (but not working memory, inhibition and IQ) were significant predictors of QoL. Two mediation models were tested based on the hypotheses, literature and current findings. Model 1 revealed that executive planning had a negative direct effect on QoL when the mediator, self-determination capacity, was held constant. Model 2 indicated that the significant association between self-determination and QoL was not mediated by executive planning.

CONCLUSIONS

The findings highlighted the crucial significance of self-determination, in comparison with executive functions and intelligence, for improving the QoL in adolescents with ID. Importantly, higher executive planning skill was even associated with lower QoL if self-determination was not concurrently strengthened. These findings carry implications for the design of education and intervention programmes aimed at improving QoL of adolescents with ID.

Effects of Smartphone Activities on Postural Balance in Adolescents with Intellectual Disabilities

Considering the rising prevalence of smartphone usage among adolescents with intellectual disabilities and their frequent motor challenges, understanding its impact on their physical well-being is important. This study aims to investigate the impact of smartphone activities on postural balance in adolescents with intellectual disabilities. Two groups of adolescents participated in the study: an intellectual disability group (IDG) (n = 16) and atypical development group (TDG) (n = 12). Static postural balance, using a stabilometric platform on firm and foam surfaces, and dynamic balance, using the Timed Up-and-Go Test (TUGT), were performed under various conditions, such as playing a game, watching videos, video calls, and listening to music. The center of pressure (CoP) values significantly increased (p < 0.05) during all smartphone activities (except listening to music) compared to the control condition in both groups, with the IDG demonstrated a more pronounced increase (p < 0.05) during playing video games and video calls on the firm surface. TUGT scores significantly increased (p < 0.05) during smartphone activities, with greater changes observed in the IDG (p < 0.05), and significantly decreased (p < 0.01) during listening to music in both groups. Our study suggests that adolescents with intellectual disabilities need special tools and guidance to ensure their safety and well-being when using smartphones.

Cognitive dysfunction and psychopathology: a cohort study of adults with intellectual developmental disorder

BACKGROUND

Cognitive impairment of intellectual developmental disorders (IDD) is determined by several different combinations of specific cognitive alterations. People with IDD present a rate of mental health problems that is up to 4 times higher than that of the general population. Despite this, the relationship between specific cognitive dysfunctions and co-occurring mental disorders has not been adequately studied. The aim of the present paper is to investigate the association between specific cognitive dysfunctions and specific psychiatric symptoms and syndromes in people with IDD.

METHODS

One hundred and twenty adults with mild to moderate IDD living in residential facilities underwent a clinical and instrumental assessment for specific cognitive and psychopathological features.

RESULTS

Participants with IDD and ASD have significantly lower scores compared to those without respect to who has not the diagnosis on the Processing Speed Index (PSI) and Perceptual Reasoning Index (PRI) on the WAIS-IV and higher time scores on the TMT A. Moreover, there is a significant association between years of hospitalisation and TMT B and TMT B A time scores; the longer a participant with IDD was hospitalised, the worse their performance on the TMT. Although not statistically significant, many psychopathological clusters showed substantial cognitive profiles.

CONCLUSIONS

Although further research is needed, neuropsychological and IQ tests scores seem to be differently associated to various psychopathological conditions co-occurring with IDD, and with ASD especially. Cognitive assessment seems to support diagnosis and treatment of psychopathological co-occurrences in persons with IDD, also in consideration of indirect implications including a better knowledge of the patient's characteristics beyond IQ deficit.

The Perfect Match! A Review and Tutorial on Issues Related to Matching Groups in Investigations of Children with Neurodevelopmental Conditions

Research concerned with children and young people who have neurodevelopmental disabilities (ND) in relation to early language acquisition usually involves comparisons with matched group(s) of typically developing individuals. In these studies, several important and complex issues need to be addressed. Three major issues are related to: (1) the choice of a variables on which to carry out group matching; (2) recruiting children into the study; and (3) the statistical analysis of the data. To assist future research on this topic, we discuss each of these three issues and provide recommendations about what we believe to be the best course of action. To provide a comprehensive review of the methodological issues, we draw on research beyond the topic of early language acquisition. Our overall aim is to contribute to research that considers questions about delay or differences in development patterns of development and about identifying potentially causal variables.

Behaviours that Challenge in SATB2-associated Syndrome: Correlates of Self-injury, Aggression and Property Destruction

SATB2-associated syndrome (SAS) is a genetic syndrome characterised by intellectual disability, severe speech delay, and palatal and dental problems. Behaviours that challenge (BtC) are reported frequently; however, there is limited research on specific forms of BtC and the correlates of these behaviours. The current study explores correlates of well-defined BtC, self-injury, aggression, and property destruction, in SAS. Eighty-one parents/caregivers of individuals with SAS (53.1% male, Mage 10.12 years) completed questionnaire measures of health, behavioural, emotional, and autism characteristics. Individuals with SAS were grouped based on caregiver responses to the presence or absence of self-injury, aggression, and property destruction on the Challenging Behaviour Questionnaire. Rates of self-injury, aggression and property destruction were 42%, 77% and 49%, respectively. Between-group comparisons were conducted to compare characteristics between behaviour groups. Significantly differing characteristics were entered into separate hierarchical logistic regressions for each form of BtC. Behavioural comparisons indicated variation in the characteristics associated with each behaviour. All hierarchical logistic regression models were significant (p < .001): self-injury (χ2(5) = 38.46, R2 = 0.571), aggression (χ2(4) = 25.12, R2 = 0.414), property destruction (χ2(4) = 23.70, R2 = 0.346), explaining between 34.6% and 57.1% of the variance in behaviour presence. This is the first study to identify correlates of self-injury, aggression, and property destruction in SAS. Variability in the characteristics associated with each behaviour highlights the importance of specificity when examining BtC. Understanding correlates of specific forms of BtC has important implications for informing SAS-associated pathways to behavioural outcomes and the implementation of tailored behavioural interventions.

Toward understanding and enhancing self-determination: a qualitative exploration with autistic adults without co-occurring intellectual disability

Introduction

Self-determination is a fundamental human right positively related to quality of life. However, Autistic people are reported to be less self-determined than non-autistic people. We aimed to (1) understand what self-determination means to Autistic people from their perspective, (2) explore their perceptions of current barriers to being self-determined, and (3) learn from Autistic people about how they would like to be supported to be self-determined.

Methods

Semi-structured interviews were done with 19 Autistic adults without co-occurring intellectual disability. Data were analyzed by three Autistic and two non-autistic researchers through an iterative process of data familiarization, coding, and theme development, informed by reflexive thematic analysis. Autistic Community Partners (ACP) were also engaged throughout the study, and provided substantive feedback on all methods and results.

Results

Self-determination held the same meaning for Autistic people as non-autistic people. More specifically, participants discussed having the opportunity and support to make choices and decisions in life without unnecessary control from others. Experiences of self-determination were centered around: (1) lack of opportunity, influenced by ableist expectations and discrimination, and (2) executive processing differences that interfered with choice and decision-making. Desired areas of support related to providing opportunities to (1) make choices and exert autonomy, (2) be supported to unmask and be valued as one's authentic Autistic self, and (3) offering pragmatic support for executive processing differences.

Conclusion

Autistic adults desire to be self-determined and can flourish with support, as they determine to be appropriate, which might look different from support commonly offered or sought by non-autistic people. Although individualized support was discussed, the ideal desired support was for an inclusive society that values and respects their neurodivergence, rather than imposing ableist expectations. An inclusive society is only achievable through reduced (or eliminated) stigma and prejudice against Autistic people.

Scoping review of dual-task interference in individuals with intellectual disability

Dual-task paradigms can provide insights on the structures and mechanisms underlying information processing and hold diagnostic, prognostic, and rehabilitative value for populations with cognitive deficits such as in individuals with intellectual disability (ID). In this paradigm, two tasks are performed separately (single-task context) and concurrently (dual-task context). The change in performance from single- to dual-task context represents dual-task interference. Findings from dual-task studies have been largely inconsistent on whether individuals with ID present with dual-task-specific deficits. The current review aimed to map the published literature on dual-task methods and pattern of dual-task interference in individuals with ID. A scoping review based on Arksey and O'Malley's five-stage methodological framework was performed. Seventeen electronic databases and registries were searched to identify relevant studies, including gray literature. Charted data from included studies were analyzed quantitatively and qualitatively. PRISMA guidelines informed the reporting of this review. Twenty-two studies involving 1,102 participants (656 with ID and 446 without ID) met the review's inclusion criteria. Participants in the included studies were heterogeneous in sex, age (range 3-59 years), etiology and ID severity. Included studies characterized their ID-sample in different ways, most commonly using intelligence quotient (IQ) scores. Other measures of intellectual function (e.g., mental age, ID severity, verbal and/or visuospatial ability scores) were also used, either solely or in combination with IQ. Methods of dual-task testing varied across studies, particularly in relation to dual-task combinations, equation of single-task performance between groups, measurement and reporting of dual-task performance for each single-task, and task priority instructions. Thematic content of the included studies were: (1) structural interference to dual-tasking; (2) etiology-based differences in dual-tasking; (3) gait and balance dual-task performance; (4) testing executive function using dual-task paradigms; and (5) training effect on dual-task performance. Although the evidence consistently supported the intact dual-tasking ability of individuals with ID, the pattern of dual-task interference was inconsistent. Likewise, the evidence was inconclusive regarding dual-task deficit specific to individuals with ID because of heterogeneity in dual-task study designs among included studies.

Dual-Task Training Effects on the Cognitive-Motor Interference in Individuals with Intellectual Disability

This study explored the effect of dual task (DT) training compared to single task (ST) training on postural and cognitive performances in DT conditions in individuals with intellectual disability (ID). Postural sways and cognitive performances were measured separately and simultaneously before and after 8 weeks in the ST training group (STTG), the DT training group (DTTG) and the control group (CG) that did not received any training. Before training, postural sways and cognitive performances were higher in the DT condition compared to ST one in all groups. After training, postural sways were higher in the DT condition compared to the ST only in the STTG and the CG. The cognitive performance increased after training only in the DTTG.

Identifying and removing ableism from Tier 1 school-wide positive behaviour support practices

Across Australia, almost one third of schools have been trained to implement school-wide positive behaviour support (SWPBS). As part of a Tier 1 approach, students are expected to demonstrate expected behaviours. By defining these behaviours in conjunction with students and families, and explicitly teaching these to students, schools implementing SWPBS can create climates where students can thrive both academically and behaviourally. However, many students with disability continue to be over-represented in discipline data in all schools, including those implementing SWPBS. We argue this is because defining the behaviours we want to see and celebrate is only part of the solution. Implementation is destined to fail if we do not, in tandem, address the conditions we created that act as barriers for students with disability. Further, through an analysis of Australian SWPBS matrices, we show that structural ableism exists in the way some expected behaviours are framed by requiring a greater response effort from students with disability if they are to meet the standard expected. We offer suggestions for schools to both recognise and remove ableism from Tier 1 SWPBS practices.

Acute effects of aerobic versus resistance exercises on cognitive function in individuals with intellectual disability

BACKGROUND

This study compared the acute effects of aerobic (AE) and resistance (RE) exercise on reaction time (RT) and working memory (WM) in individuals with intellectual disability.

METHODS

RT tests and Corsi test for WM were performed before and after three intervention sessions: AE, RE, or control session consisting on watching video.

RESULTS

The RT values decreased significantly (p < .001) after both of AE and RE with higher extend after the RE but did not vary following the control session. Corsi scores increased significantly (p < .001) after AE but not after RE or control session.

CONCLUSIONS

These findings suggest that the effects of acute exercise on cognitive function in individuals with intellectual disability depend on the exercise mode as well as the nature of the cognitive task. The RE seems to be more recommended for RT enhancement whereas only the aerobic one could improve WM in these individuals.

Protocol for a cluster randomised crossover pilot trial of Goal Management Training+ (GMT+) for methamphetamine use disorder

Background

Methamphetamine use disorder (MUD) is associated with executive dysfunctions, which are linked with poorer treatment outcomes. However, current treatments for MUD do not directly address cognition. We recently modified Goal Management Training (now Goal Management Training⁺; GMT⁺), a group-based intervention originally designed to improve executive functions after brain injury, to enhance suitability for MUD. Here, we describe the rationale and design of a trial which aims to determine the acceptability and feasibility of GMT⁺ during residential rehabilitation for MUD, and its impact on executive functions and clinical outcomes.

Methods

We used a cluster randomised crossover design: participants are randomised at the cluster level to receive either GMT⁺ or psychoeducation-control (Brain Health Workshop; BHW). GMT⁺ is delivered in four 90-min weekly sessions and includes a between-session journal with 10-min daily activities. The program targets attention, impulse control, goal-setting, and decision-making. BHW is a health-oriented intervention that delivers information about the brain and promotes healthy exercise, diet, and sleep. It is matched to GMT⁺ on program format, length, and time with therapists. We will recruit forty-eight participants with MUD from residential treatment services. Our primary outcomes are acceptability, feasibility, and self-reported executive functioning. Secondary outcomes include craving, quality of life and cognitive performance. Outcome assessments are performed at baseline, post-interventions, 4-week follow-up, and 12-week follow-up.

Conclusions

This study will provide GMT⁺ feasibility and acceptability data and will indicate initial efficacy on executive functions and clinical outcomes in residential treatment for MUD. Information from this pilot trial will inform a powered RCT.

Serious Games for Executive Functions Training for Adults with Intellectual Disability: Overview

(1) Background: Throughout the history of medical and psychology practice, specialists have worked to improve the quality of treatment and rehabilitation, which has led to the emergence of concepts such as serious games. These tools focus on different areas of intervention procedures, one of which is to help people with intellectual disability (ID). Individuals with ID have problems with executive functions (EFs), which are related to adaptive functioning. Recent studies showed that serious games positively impact cognitive, social, and communication skills in people with ID. The purpose of this study is to analyze the solutions that have been found in EF training for adults with ID in recent years, evaluating them with a number of key parameters and identifying the features and possible problems in the further development of our system. (2) Methods: A review was conducted starting with 573 articles in English related to serious games and selected from studies that had been published since 2015. Finally, 10 were examined in detail as they focused on EFs in adults with ID. They were searched in seven major databases ("Association for Computing Machinery" (ACM), IEEE Xplore database, DBLP computer science bibliography, Google Scholar, PubMed, SCOPUS, and PsycInfo). (3) Results: It was determined that the most frequent EFs referred to in the studies analyzed were planning and decision-making, followed by working memory and social cognition, behavioral regulation, flexibility, and inhibition capacity. The basic approach to the creation of support systems was also analyzed in terms of technical and program execution. The trend results' analysis evidenced improvements in EFs, even though they were not significant. This comprehensive technique enabled the identification of the main features and aspects to be taken into account for further development of our system.

Investigating the Relation of Intelligence and Executive Functions in Children and Adolescents with and without Intellectual Disabilities

Despite their separate research traditions, intelligence and executive functioning (EF) are both theoretically and empirically closely related to each other. Based on a subsample of 8- to 20-year-olds of the standardization and validation sample (N = 1540) of an internationally available instrument assessing both cognitive abilities, this study aimed at investigating a comprehensive structural model of intelligence and EF tasks and at gaining insight into whether this comprehensive model is applicable across sexes and age groups as well as to a subsample of participants with (borderline) intellectual disabilities (IQ ≤ 85, n = 255). The results of our exploratory factor analysis indicated one common EF factor that could be sufficiently integrated into the intelligence model within our confirmatory factor analyses. The results suggest that the EF factor can be added into the model as a sixth broad ability. The comprehensive model largely showed measurement invariance across sexes and age groups but did not converge within the subsample of participants with (borderline) intellectual disabilities. The results and implications are discussed in light of the current literature.

The structure of executive functioning in 11 to 14 year olds with and without special educational needs

The structure and development of executive functioning (EF) have been intensively studied in typically developing populations, with little attention given to those with Special Educational Needs (SEN). This study addresses this by comparing the EF structure of 132 adolescents (11-14 years-old) with SEN and 138 adolescents not requiring additional support (Non-SEN peers). Participants completed verbal and non-verbal assessments of key components of EF: inhibition, working memory and switching. Confirmatory Factor Analysis on each group tested one-, two- and three-factor models of EF. In both groups, there was statistical support for the fit of one- and two-factor models with no model being clearly better than the others; there was little support for three-factor models. Parsimony suggests that the one-factor model best represents the structure of EF. In light of our results, the implications for the nature of EF in early adolescence in both SEN and Non-SEN groups are discussed.

An Item Response Theory Analysis of the Wisconsin Card Sorting Test in Normal Aging, Alzheimer's Disease and Parkinson's Disease: Neurophysiological Approach

The Wisconsin Card Sorting Test (WCST) is widely used to assess executive function, specifically mental flexibility. Item Response Theory (IRT) has several advantages over classical test theory, including the invariance of the measure. This study aimed to apply IRT to study the psychometric properties of WCST in control subjects and patients with idiopathic Parkinson's disease (PD) and Alzheimer's disease (AD). The sample consisted of 86 controls, 77 Parkinson's disease subjects, and 155 AD subjects. The Rasch model was applied to binary data from the conversion to percentiles adjusted for age and schooling. The R program was used to calibrate the difficulty parameter. The characteristic curves of the items and the estimation of the difficulty parameter for each diagnostic group were obtained. WCST makes it possible to separate between different skill levels among the three diagnostic entities and its application may be useful for other neuropsychological tests. In conclusion, WCST has good clinical sensitivity and excellent discriminant validity in the groups under study, making it possible to separate them between different levels of ability or latent trait. Its application may be useful for other neuropsychological tests.

Associations of Motor Performance and Executive Functions: Comparing Children with Down Syndrome to Chronological and Mental Age-Matched Controls

Background. Children with Down syndrome (DS) exhibit lower motor and cognitive performance than typically developing children (TD). Although there is a relationship between these two developmental domains, only a few studies have addressed this association in children with DS compared to groups of the same chronological age (CA) or mental age (MA) within one study. This study aimed to fill this research gap. Method and Procedures. The Movement Assessment Battery for Children-2 and the Trail-Making Test was used to assess motor and cognitive performances in 12 children (M = 10.5 ± 10.08) with DS, 12 CA-matched, and 12 MA-matched controls. Results. There are significant group differences in the motor dimension (total test score; p < 0.001, η²_p = 0.734), for processing speed (p < 0.001, η²_p = 0.396), and cognitive flexibility (p < 0.001, η²_p = 0.498). Between TD-CA and both other groups, the differences in the magnitude of correlations for the motor dimension balance are also significant (compared to DS: z = −2.489; p = 0.006, and to TD-MA: z = −3.12; p < 0.001). Conclusions. Our results suggest that the relationships depend on the studied cognitive and motor skills. It seems crucial to select a wide range of tasks for both domains that are as isolated as possible for future studies, to better understand the relationships between cognitive and motor skills in children with DS.

Executive function and intellectual disability: innovations, methods and treatment

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.