Executive functions and adaptive behaviour in individuals with Down syndrome

Role of child demographic, executive functions, and behavioral challenges on feelings about parenting among parents of youth with Down syndrome

BACKGROUND

Living with a child with Down syndrome (DS) influences the entire family, including caregivers.

AIMS

This study examined positive and negative caregiver feelings about parenting youth with DS and to what extent children's demographic, cognitive, behavioral characteristics, and co-occurring medical conditions are associated with those parental feelings. Specifically, the mediatory role of child behavioral challenges on the relationship between child executive functioning (EF) and parent feelings about parenting a child with DS was examined in a mediation analysis model.

METHODS AND PROCEDURES

Parents of 113 youth with DS aged 6 to 17 year rated their positive and negative feelings about parenting, and their child's behavioral challenges and EF.

OUTCOMES AND RESULTS

Externalizing and Internalizing behavioral challenges and emotional and behavioral regulations of EF were significantly associated with positive and negative parent feelings. Child behavioral challenges fully mediated the relationship between child EF and caregiver feelings about parenting, after controlling for identified covariates of child demographics.

CONCLUSIONS AND IMPLICATIONS

Findings have implications for understanding the role of EF, through its impact on behavioral challenges, on the feelings of caregivers about parenting a child with DS. These findings play a role in understanding outcomes of interventions targeted at EF and behavioral challenges, in the context of other child variables.

Cross-sectional developmental trajectories in the adaptive functioning of children and adolescents with Down syndrome

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.

Psychometric properties of inhibitory control measures among youth with Down syndrome

BACKGROUND

Inhibitory control measures have been commonly used when assessing individuals with Down syndrome. However, minimal attention has been devoted to evaluating the appropriateness of specific assessments for use in this population, potentially leading to erroneous conclusions. This study aimed to examine the psychometric properties of measures of inhibitory control among youth with Down syndrome. We sought to examine the feasibility, presence of floor or practice effects, test-retest reliability, convergent validity and correlations with broader developmental domains of a set of inhibitory control tasks.

METHODS

A sample of 97 youth with Down syndrome aged 6 to 17 years old participated in verbal and visuospatial tasks of inhibitory control including the Cat/dog Stroop, Neuropsychological Assessment Second Edition (NEPSY-II) Statue, National Institutes of Health (NIH) Toolbox Cognition Battery (TCB) Flanker, Leiter-3 Attention Sustained, and the Test of Attentional Performance for Children (KiTAP) Go/No-go and Distractibility subtests. Youth also completed standardised assessments of cognition and language, and caregivers completed rating scales. Psychometric properties on the tasks of inhibitory control were evaluated against a priori criteria.

RESULTS

Apart from demonstrating negligible practice effects, adequate psychometric properties were not observed for any inhibitory control measure within the current sample's age range. One task with low working memory demands (NEPSY-II Statue) generally had better psychometric properties than the other tasks assessed. Subgroups of participants with an IQ greater than 30 and age more than 8 years were shown to be more likely to be able to complete the inhibition tasks.

CONCLUSIONS

Findings suggest better feasibility for analogue tasks rather than computerised assessments of inhibitory control. Given the weak psychometrics of several common measures, future studies are required to evaluate other inhibitory control measures, specifically those with reduced working memory demands for youth with Down syndrome. Recommendations for use of the inhibitory control tasks among youth with Down syndrome are provided.

Evaluating an adapted reverse categorisation task to assess cognitive flexibility in young children with Down syndrome

BACKGROUND

Accurate measurement of cognitive skills is necessary to advance both developmental and intervention science for individuals with Down syndrome (DS). This study evaluated the feasibility, developmental sensitivity and preliminary reliability of a reverse categorisation measure designed to assess cognitive flexibility in young children with DS.

METHODS

Seventy-two children with DS ages 2.5-8 years completed an adapted version of a reverse categorisation task. Twenty-eight of the participants were assessed again 2 weeks later for retest reliability.

RESULTS

This adapted measure demonstrated adequate feasibility and developmental sensitivity, and preliminary evidence for test-retest reliability when administered to children with DS in this age range.

CONCLUSIONS

This adapted reverse categorisation measure may be useful for future developmental and treatment studies that target early foundations of cognitive flexibility in young children with DS. Additional recommendations for use of this measure are discussed.

Profiles of Caregiver-Reported Executive Function in Children with Down Syndrome

Children with Down syndrome (DS) are at risk for challenges with aspects of executive function (EF). The current study explores whether heterogeneity in EF profiles can be detected within a sample of children with DS. Participants were 69 children with DS, ages 3-10 years (M = 6.23, SD = 1.91). T-scores from a caregiver-report measure of executive function were modeled using latent profile analysis, and auxiliary analyses examined the association between demographic and biomedical factors and probability of profile membership. The two-profile solution was the best fit for the sample, with a profile that involved elevated scores in working memory only ("Working Memory Only" profile; 43% of sample) and a "Multi-Domain" profile that involved elevated scores in planning, inhibition, and working memory (57%). The presence of congenital heart defects was associated with a higher probability of assignment to the Multi-Domain profile. Findings from this study contribute to the characterization of heterogeneous outcomes associated 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.