Clusters that are not there: An R tutorial and a Shiny app to quantify a priori inferential risks when using clustering methods.

Clustering methods are increasingly used in social science research. Generally, researchers use them to infer the existence of qualitatively different types of individuals within a larger population, thus unveiling previously "hidden" heterogeneity. Depending on the clustering technique, however, valid inference requires some conditions and assumptions.

Sex/gender differences in general cognitive abilities: an investigation using the Leiter-3.

Research has shown that differences between males and females are not in general intelligence, but only in some specific factors and tasks. We used the Italian standardization of the Leiter-3, which is a completely nonverbal cognitive battery, to investigate the nature of sex/gender (we used sex/gender to reflect the awareness that the effects of biological 'sex' and socially constructed 'gender' cannot be easily separated and that most individuals' identities are informed by both sex and gender) differences. In doing so we used a multigroup confirmatory factor analysis approach.

The Intellectual Profile of Adults with Specific Learning Disabilities.

Despite growing research on adults with specific learning disabilities (SLDs), evidence concerning their intellectual profile remains scarce. The present study examined the results of the administration of the Wechsler Adult Intelligence Scale-Fourth Edition to 301 adults diagnosed with SLDs and compared them to the results obtained from previous studies with a large sample of children with SLDs. The results showed that: (1) as observed among children, adults with SLDs also presented higher scores in the subtests implying reasoning (associated with the General Ability Index, GAI) and lower scores in the subtests involving working memory and processing speed; (2) the discrepancy between full-scale IQ and the GAI had a good predictive value in discriminating adults with and without SLDs; (3) the four-factor hierarchical structure of intelligence proposed for the general adult population held for adults with SLDs as well, even though there were substantial differences in the loadings and a five-factor structure could be more appropriate; (4) similarities as well as strong differences were present between adults and children with SLDs.

Maths anxiety and subjective perception of control, value and success expectancy in mathematics.

Mathematics anxiety (MA) is an academic anxiety related to doing, learning and testing mathematics. MA can negatively affect mathematics performance, motivation and maths-heavy science and technology-related career choices. Previous data suggest that subjective perceptions and interpretations of students are key in the genesis of MA.

Oral language interventions can improve language outcomes in children with neurodevelopmental disorders: A systematic review and meta-analysis.

Background: Young people who fail to develop language as expected face significant challenges in all aspects of life. Unfortunately, language disorders are common, either as a distinct condition (e.g.

Gender Differences in the Wechsler Intelligence Scale for Children in a Large Group of Italian Children with Attention Deficit Hyperactivity Disorder.

Despite being repeatedly investigated in children with typical development, research on gender differences in intellectual abilities in specific groups of children, including children with attention deficit hyperactivity disorder (ADHD), has been scarce. In this paper, we evaluated the performance of a large group of Italian children with ADHD using the WISC-IV. We aimed at investigating the presence of gender differences using a multi-group confirmatory factor analysis approach.

Developmental profiles of young children with autism spectrum disorder and global developmental delay: A study with the Griffiths III scales.

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.

Navigability of Residential Care Homes From Residents', Family Members', and Staff's Points of View: The Residential Care Home Navigability Scale.

Background And Objectives: Navigational skills display clear signs of decline with increasing age, especially in pathological aging. Therefore, navigability-the extent to which destinations can be reached with reasonable effort and time-should be considered in residential care home design. We aimed to develop a scale assessing environmental features (i.

Efficacy of memory training interventions targeting metacognition for older adults: a systematic review and meta-analysis.

Objectives: This review examined the evidence about training interventions targeting metacognition in improving memory and cognitive performance, metacognitive functioning, and well-being in healthy older adults.

Methods: Studies were identified in the PsycInfo, PubMed, and Scopus databases. The risk of bias was assessed using tools based on the Joanna Briggs criteria.

The structure, profile, and diagnostic significance of intelligence in children with ADHD are impressively similar to those of children with a specific learning disorder.

This study examines the structure, profile, and diagnostic significance of intelligence in a group of 948 children diagnosed with attention deficit/hyperactivity disorder (ADHD) assessed with the WISC-IV and compared with children with specific learning disorders (SLDs) and with typically developing children. Based on four indexes, the WISC-IV configuration found in TD resulted applicable to ADHD, but with generally lower loadings on g. The Perceptual Reasoning and Verbal Comprehension indexes not only had higher loadings compared to the other two indexes but also represented the relative strengths of children with ADHD, as previously observed for children with SLD.

Entia Non Sunt Multiplicanda … Shall I look for clusters in my cognitive data?

Unsupervised clustering methods are increasingly being applied in psychology. Researchers may use such methods on multivariate data to reveal previously undetected sub-populations of individuals within a larger population. Realistic research scenarios in the cognitive science may not be ideally suited for a successful use of these methods, however, as they are characterized by modest effect sizes, limited sample sizes, and non-orthogonal indicators.

Structure of working memory in children from 3 to 8 years old.

Several models of working memory (WM) have been proposed in the literature. Most of the research on the architecture of WM is based on adults or older children, but less is known about younger children. In this study, we tested various models of WM on a sample of 739 Italian children, ranging in age from 3 to 8 years, primarily of European heritage and from medium to medium-high socioeconomic background.

Non-pharmacological interventions targeting sleep quality in older adults: a systematic review and meta-analysis.

Objectives: This review aimed to examine the available evidence about non-pharmacological interventions (NPIs) aimed at improving sleep quality in older adults without insomnia or dementia. Studies on NPIs targeting older adults' sleep were searched in the PsycInfo, PubMed and Scopus databases, with no restriction on publication year up to September 2021. Studies on NPIs for older adults with no diagnosed sleep disorders were included, while those on pharmacological therapies and/or concerning pathological samples were excluded.

Individuals with Down Syndrome: Editorial.

Down syndrome (DS) is the most common syndromic cause of intellectual disability, so it has long been of interest to researchers [...

Developmental trajectories of spatial-sequential and spatial-simultaneous working memory in Down syndrome.

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.

The relationship between sleep quality and quality of life in aging: a systematic review and meta-analysis.

This study examined the available literature concerning the association between sleep quality and quality of life (QoL) in autonomous older people with no sleep disorders. A systematic review and meta-analysis were conducted on studies identified in the PsycInfo, PubMed and Scopus databases that examined the associations between QoL and sleep quality in older adults. Our systematic literature search identified 23 studies concerning a total of 21,092 participants (range of mean ages: 58-79 years).

Difficulties of Young Adults With Dyslexia in Reading and Writing Numbers.

Letters and numbers are different domains, and their differentiation increases with schooling. It has nonetheless been argued that reading alphabetic and numerical materials partly involves the same processes, even in adults. Whether individuals with dyslexia have difficulty reading and writing numbers remains to be established.

Is the Age of Developmental Milestones a Predictor for Future Development in Down Syndrome?

Down Syndrome (DS) is the most common genetic alteration responsible for intellectual disability, which refers to deficits in both intellectual and adaptive functioning. According to this, individuals with Down Syndrome (DS) reach developmental milestones (e.g.

Developmental Trajectories in Spatial Visualization and Mental Rotation in Individuals with Down Syndrome.

Background: The analysis of developmental trajectories of visuospatial abilities in individuals with Down Syndrome (DS) remains an unexplored field of investigation to examine in depth. The study aimed to fill such a gap by examining changes in two visuospatial abilities: spatial visualization (the ability to manage spatial stimuli) and mental rotation (the ability to rotate spatial stimuli).

Method: Eighty-seven participants with DS, aged between 7 and 53 years (forty-seven males and forty females), completed spatial visualization and mental rotation tasks.

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.

Dyslexia treatment studies: A systematic review and suggestions on testing treatment efficacy with small effects and small samples.

Poor response to treatment is a defining characteristic of reading disorder. In the present systematic review and meta-analysis, we found that the overall average effect size for treatment efficacy was modest, with a mean standardized difference of 0.38.

No evidence for a core deficit in developmental dyscalculia or mathematical learning disabilities.

Background: Two hypotheses were tested regarding the characteristics of children with mathematical learning disabilities (MLD): (a) that children with MLD would have a 'core deficit' in basic number processing skills; and (b) that children with MLD would be at the end of a developmental continuum and have impairments in many cognitive skills.

Methods: From a large sample (N = 1,303) of typically developing children, we selected a group definable as having MLD. The children were given measures of basic number processing and domain-general constructs.

Self-reported sleep quality and dysfunctional sleep-related beliefs in young and older adults: changes in times of COVID-19 lockdown.

Objective: This study examined changes due to COVID-19 lockdown in young and older adults' self-reported sleep quality and dysfunctional sleep-related beliefs.

Methods: Adults involved in studies prior to the pandemic were contacted during the COVID-19 lockdown. Seventeen young adults (age range: 18-35 years) and 21 older adults (age range: 65-90 years) agreed to participate.