Expressive vocabulary predicts non-verbal executive function: a 2-year longitudinal study of deaf and hearing children

Numerous studies suggest an association between language and executive function (EF), but evidence of a developmental relationship remains inconclusive. Data were collected from 75 deaf/hard-of-hearing (DHH) children and 82 hearing age-matched controls. Children were 6-11 years old at first time of testing, and completed a battery of nonverbal EF tasks and a test of expressive vocabulary. These tasks were completed again two years later. Both groups improved their scores on all tasks over this period. DHH children performed significantly less well than hearing peers on some EF tasks and the vocabulary test at both time points. Cross-lagged panel models showed that vocabulary at Time 1 predicted change in EF scores for both DHH and hearing children but not the reverse

How to understand it: Neuropsychological testing

Neuropsychological testing is a key diagnostic tool for assessing people with dementia and mild cognitive impairment, but can also help in other neurological conditions such as Parkinson’s disease, stroke, multiple sclerosis, traumatic brain injury and epilepsy. While cognitive screening tests offer gross information, detailed neuropsychological evaluation can provide data on different cognitive domains (visuospatial function, memory, attention, executive function, language and praxis) as well as neuropsychiatric and behavioural features. We should regard neuropsychological testing as an extension of the neurological examination applied to higher order cortical function, since each cognitive domain has an anatomical substrate. Ideally, neurologists should discuss the indications and results of neuropsychological assessment with a clinical neuropsychologist. This paper summarises the rationale, indications, main features, most common tests and pitfalls in neuropsychological evaluation

Macro-Level Cognitive and Linguistic Function in Early Stage Alzheimer’s Disease and Mild Cognitive Impairment

Alzheimer’s disease (AD) is a global health concern, particularly as there is currently no cure for the disease. Interventions to slow progression of disease, pharmacological or non-pharmacological, need to be targeted early on before any significant neurodegeneration has occurred, as these changes are irreversible, and lost cognitive function cannot be recovered. This makes it imperative to detect pathological cognitive decline as early as possible. Although biomarkers have received a lot of attention in this regard, they have several limitations, particularly outside of research settings, such as cost and availability. Cognitive markers, other than traditional neuropsychological test measures, on the other hand, have received comparatively less attention with regards to early detection; and, particularly cognitive markers that are rooted in real-world, everyday cognition, have been lacking. Due to the disease being incurable, interventions are aimed at maintaining independent living and good quality of life for as long as possible. This necessitates outcomes that can measure meaningful change in cognition and everyday functioning. The goal of the present dissertation was to identify gaps in the current literature on cognitive and linguistic assessments that are embedded in aspects of everyday cognition in AD, and work towards developing paradigms to address the gaps. Due to the emphasis on early detection, the work focused on patients in the very early stage of AD and on its preceding stage of Mild Cognitive Impairment (MCI). In light of evidence reporting the inability of AD patients to follow narratives, be it verbal or non-verbal, a systematic review of text comprehension studies was conducted to characterize and evaluate macro-level measures of discourse comprehension in their sensitivity to early stage AD, and their ability to distinguish pathological ageing due to AD or MCI from cognitive ageing. Results showed that, not only AD patients, but also MCI patients were significantly more impaired on macro-level measures of comprehension compared to cognitively healthy older adults. These findings were consistent across all eight studies included in the review, indicating a robust effect, though there were minor differences in the sensitivity of different measures. Next, moving towards non-verbal narratives, a novel picture-based paradigm assessing event cognition, with a focus on event integration and macro-event recognition, was introduced. This study aimed to examine the macro-level processing of events by using a format requiring integration of micro-events, depicted in pictures, into a larger macro-event. AD and MCI patients’ ability to connect the micro-events temporally and causally to identify the depicted macro-event was assessed. As hypothesized, the findings showed that patient groups had significant difficulties in determining temporal order of micro-events, even when provided with a verbal cue, as well as in conceptualizing the macro-event from the presented micro-events, when compared to healthy older adults. Finally, using traditional neuropsychological tests, the cognitive processes involved in performing the macro-event recognition task were determined by examining correlations. Primarily, semantic memory and executive functioning appear to play a role. However, the strength of correlations was fairly moderate, indicating added value of event recognition task in cognitive assessment. Taken together, these findings show the sensitivity of macro-level cognitive and linguistic markers based in everyday cognition in the early stages of AD, and highlight the positive role of such cognitive assessment methods in bringing together objective assessment methods and everyday cognition

Relationship between cognitive ability, personality, psychological well-being and self-esteem among hearing-impaired students: The moderating role of emotional intelligence

Hearing-impaired students tend to face obstacle in communication due to limitations of social-emotional experiences as well as social skills aspect which potentially influenced emotional intelligence, cognitive ability, personality, psychological wellbeing and self-esteem. This study aimed to examine: (i) the level of cognitive ability dimensions, personality traits, psychological well-being dimensions, emotional intelligence dimensions and self-esteem of hearing-impaired students, (ii) the differences in cognitive ability, personality traits, psychological well-being, emotional intelligence and self-esteem of the hearing-impaired students according to gender and parents’ hearing status, (iii) the relationship between cognitive ability dimensions, personality traits, psychological well-being dimensions, emotional intelligence dimensions and self-esteem, (iv) emotional intelligence as a moderating variable and lastly, (v) factors that significantly predict students’ hearing-impaired self-esteem. Respondents were 163 hearing-impaired students from five polytechnics and were selected via simple random sampling. The descriptive and inferential statistics were analyzed using the Statistical Package for Social Sciences (SPSS). Findings of the study showed that there were significant relationships between variables in the study. There was a significant difference in cognitive ability and self-esteem according to parent’s hearing status. There were also significant relationships between self-esteem and extraversion, agreeableness and conscientiousness. The study also revealed significant relationships between self-esteem and dimensions of emotional intelligence (interpersonal and general mood) and dimensions of psychological well-being. Emotional intelligence moderated the relationships between memory, attention, neuroticism, openness, conscientiousness, self-acceptance, autonomy, purpose in life, environmental mastery and personal growth with self-esteem. The findings also showed interpersonal and agreeableness dimensions significantly contributed towards self-esteem. In conclusion, this study contributed towards enhancing the knowledge about hearing-impaired students’ self-esteem and its relation to their cognitive ability, personality traits, psychological well-being and emotional intelligence specifically in the field of developmental psychology and special education area in Malaysi

Identification of Specific Learning Disability Profiles: Consideration of Patterns across Cognitive, Academic, Socio-Emotional, and Executive Variables

During recent years, there has been a growing urgency and a heightened demand for increased accountability for all students to demonstrate academic success in school, as required by the No Child Left Behind Act (NCLB; 2002). An integral part of helping students to meet success in school includes providing them with a free and appropriate education; this also includes those students who have educational disabilities, through the provision of specially designed instruction and supports. In the past, SLD had been studied as a homogenous classification (Rourke, 1999). However, as more recent research has evolved, it has become clearer that students classified with SLD exhibit different patterns of performance (strengths and weaknesses), suggesting that they actually compose a heterogeneous group (Rourke, 1999). The current study was designed to determine and describe meaningful SLD profiles through the examination of patterns of strengths and of weaknesses across cognitive, academic, socio-emotional, and executive variables, using standard scores in a school-aged population of students identified with SLD. In this sample of data drawn from a population of students classified with SLD (n = 40), bivariate correlations and multivariate analyses of variance were performed. Students with SLD were organized into three groups by the presence of a reading-based SLD, a math-based SLD, or a mixed reading/math-based SLD. Results demonstrated significant, positive correlations between cognitive and academic variables, whereas little significance was noted between cognitive and socio-emotional or executive variables. Significant differences were found between the SLD groups (Reading SLD group, Math SLD group, and Combined Reading/Math SLD group), for cognitive and academic variables; however, no significance was found for socio-emotional or executive variables

Spatial but not verbal cognitive deficits at age 3 years in persistently antisocial individuals

Previous studies have repeatedly shown verbal intelligence deficits in adolescent antisocial individuals, but it is not known whether these deficits are in place prior to kindergarten or, alternatively, whether they are acquired throughout childhood. This study assesses whether cognitive deficits occur as early as age 3 years and whether they are specific to persistently antisocial individuals. Verbal and spatial abilities were assessed at ages 3 and 11 years in 330 male and female children, while antisocial behavior was assessed at ages 8 and 17 years. Persistently antisocial individuals (N = 47) had spatial deficits in the absence of verbal deficits at age 3 years compared to comparisons (N = 133), and also spatial and verbal deficits at age 11 years. Age 3 spatial deficits were independent of social adversity, early hyperactivity, poor test motivation, poor test comprehension, and social discomfort during testing, and they were found in females as well as males. Findings suggest that early spatial deficits contribute to persistent antisocial behavior whereas verbal deficits are developmentally acquired. An early-starter model is proposed whereby early spatial impairments interfere with early bonding and attachment, reflect disrupted right hemisphere affect regulation and expression, and predispose to later persistent antisocial behavior

Do tasks make a difference? Accounting for heterogeneity of performance of children with reading difficulties on tasks of executive function : findings from a meta-analysis

Research studies have implicated executive functions in reading difficulties (RD). But while some studies have found children with RD to be impaired on tasks of executive function other studies report unimpaired performance. A meta-analysis was carried out to determine whether these discrepant findings can be accounted for by differences in the tasks of executive function that are utilized. A total of 48 studies comparing the performance on tasks of executive function of children with RD with their typically developing peers were included in the meta-analysis, yielding 180 effect sizes. An overall effect size of 0.57 (SE .03) was obtained, indicating that children with RD have impairments on tasks of executive function. However, effect sizes varied considerably suggesting that the impairment is not uniform. Moderator analysis revealed that task modality and IQ-achievement discrepancy definitions of RD influenced the magnitude of effect; however, the age and gender of participants and the nature of the RD did not have an influence. While the children's RD were associated with executive function impairments, variation in effect size is a product of the assessment task employed, underlying task demands, and definitional criteria

The Linguistic and Cultural Aspects of Neuropsychological Assessment in People with Dementia

Objectives: Given the public health crisis that Alzheimer's disease (AD) has become (Naylor et al., 2012),neuropsychological assessment tools that provide timely and accurate identification of cognitive decline in older adults have gained increasing focus in the scientific literature. Accurate evaluation of cognitive function and early identification of cognitive changes are paramount to understanding the disease course of AD and improving effective treatments and patients' quality of life. To this end, language offers a cognitive neuropsychological approach to identifying cognitive decline in the early stages of AD. Moreover, it represents a multi-dimensional variable that may influence the neuropsychological test performance of older adults due to its potential contribution to cognitive reserve. Therefore, the present thesis aims at combining two aspects of language to explore its potential in the early detection of AD and its association with neuropsychological test performance in older adults and cross-cultural neuropsychology. Study 1 assessed the currently available studies to explore whether discourse processing, particularly macro-structural discourse comprehension, offers a novel approach to neuropsychological testing in distinguishing normal cognitive aging from AD pathology-related decline. Study 2 evaluated the results of the studies that examined the impact of bilingualism on neuropsychological test performance in monolingual and bilingual older adults to inform the neuropsychological evaluation of these groups in clinical practice. Study 3 investigated the influence of bilingualism and its associated factors, namely, cultural background and acculturation, on cognitive screening tests in three clinically diagnosed AD patient groups to identify a cross-culturally/linguistically appropriate measure of cognition. Method: Data of Study 1 and Study 2 were based on the original research studies published in English investigating discourse comprehension and bilingualism in healthy older adults, individuals with mild cognitive impairment (MCI), and AD. A literature search focusing on these topics with participant groups aged 60 years and over was conducted in PubMed, Web of Science, and PsycINFO databases. Study 1 included eight articles consisting of studies only with cross sectional designs. Study 2 was comprised of twenty-seven articles, of which sixteen articles had cross-sectional designs. On the other hand, Study 3 was original research based on a cross sectional design targeting culturally/linguistically diverse patients diagnosed with AD. Specifically, the study sample consisted of Turkish immigrant (n=21) and monolingual, non-immigrant German (n=20) and Turkish (n=24) patients with AD. All participants were administered the Mini-Mental State Examination (MMSE), Rowland Universal Dementia Assessment Scale (RUDAS), a dementia severity rating scale, and a self-report measure of depression. Additionally, self-report measures of bilingualism and acculturation were conducted with Turkish-immigrant participants with AD. Results: Study 1 revealed that people with AD and MCI have significant deficits in discourse comprehension, which are not observed in cognitively normal older adults of any age. On five of six discourse comprehension measures, groups with AD were significantly worse than healthy older adults, with one measure yielding mixed findings. Furthermore, compared to the cognitively healthy groups, individuals with MCI showed significant performance deficits in discourse comprehension measures similar to those with AD. Study 2 indicated better performance for bilingual older adults on executive function tests when compared to their monolingual counterparts. On the other hand, bilinguals were found to perform poorer than monolinguals on tests assessing the language domain. However, these findings did not remain robust when the impact of bilingualism on test performance was investigated longitudinally. Lastly, Study 3 provided further evidence on the linguistic and educational bias of the MMSE when employed in culturally and linguistically diverse individuals with AD. Bilingualism was linked to better performance on the MMSE in the Turkish immigrant group. German patients with AD obtained higher scores on this test than the other two groups. Furthermore, RUDAS was shown to be a better alternative for assessing global cognition in German and Turkish individuals with AD. Conclusion: The macro-structural discourse comprehension assessment paradigm has shown promising results in identifying the preclinical stages of AD. Further research on this paradigm may help develop a diagnostic tool with a clinical value that can be utilized for differential diagnosis, predicting conversion from MCI to dementia in research and clinical settings. On the other hand, another aspect of linguistic skills, namely, the evaluation of research on the link between bilingualism and neuropsychological test performance, did not provide definitive answers to the question of bilingual advantages and disadvantages addressed in the second study due to methodological challenges in the field. However, it identified a comprehensive and critical list of clinically and empirically relevant bilingualism-associated variables which may guide future research and neuropsychological practice. In light of the Study 2 findings, Study 3 filled an important gap in the literature by exploring cultural, demographic, and immigration related factors that may influence neuropsychological testing experiences in Germany. The study findings may help the field of cross-cultural neuropsychology serve culturally and linguistically diverse populations more efficiently. Overall, the present thesis contributed to the literature by highlighting the importance and potential of linguistic abilities in the clinical diagnosis and neuropsychological evaluation of individuals with dementia