Neuropsychology

Corpus callosum structure and auditory interhemispheric transfer in spina bifida myelomeningocele.
Objective: Maldevelopment of the posterior corpus callosum is common in spina bifida myelomeningocele (SBM) due to hydrocephalus-related hypoplasia and congenital partial hypogenesis. This study examined the relations of macro- and microstructural integrity of the interhemispheric temporal tract in SBM and auditory interhemispheric transfer using consonant–vowel dichotic listening. Method: We collected T₁-weighted and diffusion tensor imaging data from 46 individuals with SBM and 15 typically developing individuals. Probabilistic tractography was used to isolate the interhemispheric white matter connecting auditory processing regions in both hemispheres. Interhemispheric transfer was assessed with a dichotic listening task. Results: Although the typically developing group and the group with SBM showed the normative right-ear advantage, fewer participants showed a right-ear advantage in the group with SBM. The absence of the right-ear advantage was largely in the subgroup with hypogenesis of the splenium or severe posterior hypoplasia. Sex, anterior commissure cross-sectional area, and number of shunt pathways visible on magnetic resonance imaging predicted right-ear superiority. Conclusions: Interhemispheric transfer is disrupted in individuals with SBM and hypogenesis or severe hypoplasia of the posterior corpus callosum. Preservation of interhemispheric transfer is related to expected connections through the posterior corpus callosum and possibly compensatory pathways in the anterior commissure. (PsycInfo Database Record (c) 2024 APA, all rights reserved)
Is hyperactivity in children with attention deficit/hyperactivity disorder (ADHD) a functional response to demands on specific executive functions or cognitive demands in general?
Objective: Hyperactivity is a core and impairing deficit in the clinical model of attention-deficit/hyperactivity disorder (ADHD). However, the extent to which hyperactivity in ADHD is evoked by cognitively challenging tasks in general or by demands on specific executive functions remains unclear. Method: A clinically evaluated and carefully phenotyped community-referred sample of 184 children ages 8–13 (M = 10.40, SD = 1.50; 61 girls) with ADHD (n = 119) and without ADHD (neurotypical children and children with psychiatric disorders other than ADHD) were administered multiple, counterbalanced executive (working memory, inhibitory control, set shifting) and nonexecutive tests. Objective measures of gross motor movement (hyperactivity) were obtained using actigraphy. Results: Using bifactor s-1 modeling, results indicate that children with ADHD demonstrate moderately elevated levels of motor movement relative to non-ADHD children. Additionally, findings indicated that hyperactivity in ADHD reflects the outcome of at least two similarly important factors: (a) a baseline level of elevated motor movement that is independent of environmental demands on their executive and nonexecutive cognitive abilities (d = 0.72); and (b) additional elevations attributable to demands placed on specific executive functions, with working memory and inhibition demands evoking similarly large, differential increases in movement for children with ADHD above and beyond their elevated baselines (Δd = 0.80). Conclusions: These findings suggests that executive function demands exacerbate, but do not fully explain, hyperactivity in ADHD, and/or there are at least two pathways to hyperactivity in ADHD—hyperactivity caused by environmental demands that challenge their underdeveloped executive functions, and hyperactivity caused by one or more other factors that need future research to identify. (PsycInfo Database Record (c) 2024 APA, all rights reserved)
Executive function is associated with the development of math performance in children born at
Objective: To describe associations between executive function (EF) domains (attentional control, information processing, cognitive flexibility, and goal setting) and concurrent math computation performance at age 7 and 13 years in children born
Sociodemographic predictors and cross-cultural comparisons in tests performance from the Cambridge Neuropsychological Testing Automated Battery (CANTAB) among children aged 6–8 years from Montevideo, Uruguay.
Objective: Cross-culturally comparative data on measures of executive function (EF) are essential, but the 6–8-year group remains insufficiently described. This study examined the sociodemographic predictors of EF test performance employing the Cambridge Neuropsychological Testing Automated Battery (CANTAB). It also compared developmental trends in EF among children from Uruguay, the United States, and Mexico. Method: EFs were assessed with the Intra-dimensional/Extra-dimensional shift, Spatial Span (SSP), and Stockings of Cambridge (SOC) tests from the CANTAB. The study sample consisted of 6–8-year-old children from the Salud Ambiental Montevideo (SAM) cohort in Uruguay. Differences between cohorts were examined, and we performed generalized linear regressions to assess the association between sociodemographic factors, and each EF domain. Results: The final sample consisted of 525 participants (mean age in months 82.5 ± 6.0). Across all ages, SAM children had significantly lower performance in the SSP and SOC tasks compared to U.S. and Mexican children. On the Intra-dimensional/Extra-dimensional shift task, SAM children had similar scores to U.S. and Mexican children. Mother’s intelligence quotient (IQ; β = 0.01; 95% CI [0.005, 0.02]), child’s IQ (0.02 [0.02, 0.03]), the HOME total score (0.02 [0.01, 0.03]), as well as HOME subscales of accompaniment (0.13 [0.07, 0.20]), enrichment (0.11 [0.06,0.16]), and physical environment (0.07 [0.03, 0.10]) were positively associated with the span length (SSP task). Child’s IQ (0.02 [0.01,0.03]) was positively associated with the number of problems solved on the SOC test. Conclusion: Uruguayan children perform lower in working memory and planning tests than U.S. children but similarly to Mexican children, while cognitive flexibility is consistent across all groups. Further, mother and child IQ, as well as the home environment, are important predictors of EF. These differences should be examined in the context of diverse cultural values and sociodemographic factors affecting CANTAB construct validity in this population. (PsycInfo Database Record (c) 2024 APA, all rights reserved)
Association between social networks and cognition among middle-aged and older adults in rural India.
Objective: Prior studies using global cognitive measures have shown that social connectedness is linked with cognitive performance. We investigate the role of different social network dimensions on performance across distinct cognitive domains among dementia-free middle-aged and older rural Indians. Method: We utilized baseline assessment data of 2,525 participants (≥45 years) of an ongoing, prospective, aging cohort in rural India (Srinivaspura Aging, Neuro Senescence, and COGnition) for this study. We evaluated social networks using Cohen’s Social Network Index on three dimensions: network diversity, network size, and network embeddedness. We measured cognitive performance on memory (narrative recall), visuospatial ability (geometric figure spatial recognition, visuospatial span), language (verbal fluency, semantic association, word comprehension, reading comprehension), and attention domains of a culturally adapted, computerized, neurocognitive test battery. Linear regression models, adjusted for age and sex, were used for statistical analysis. Results: In the linear regression model adjusted for age and sex, we found that greater network diversity was significantly associated with better performance in narrative recall, geometric figure spatial recognition, reading comprehension, semantic association, and attention tests. Participants with a larger network size had significantly better performance in verbal fluency and semantic association tests. Further, participants with greater network embeddedness had better visuospatial span and verbal fluency. Conclusions: Individuals having a greater network diversity, larger network size, and greater network embeddedness had better cognitive performance in multiple distinct cognitive domains. Following up these participants with serial cognitive monitoring can help understand if social networks play a role in delaying cognitive decline and protecting against dementia. (PsycInfo Database Record (c) 2024 APA, all rights reserved)
Getting oriented: Redefining attention deficits in Parkinson’s disease.
Objective: Parkinson’s disease (PD) may affect not only motor functions, but also cognitive processes such as attention. While past research has examined PD impact on spatial attention, it has not addressed how the key functions of attentional orienting and alerting in PD are mediated by cueing format, an ecologically relevant parameter. We assessed how exogenous and endogenous orienting cue modes affect PD patients’ visuospatial attention expressed as dorsal attention network orienting benefits, ventral attention network reorienting costs, and alerting abilities. Method: Ninety PD patients and 72 healthy comparison participants performed a spatial attention task in an engaging game format which required selection of a target location without prior cueing, or with temporal, valid spatial, or invalid spatial exogenous or endogenous cueing. Results: PD patients differed from healthy participants only in response time benefits in orienting under endogenous probabilistically predictive cue processing. They did not exhibit greater reorienting costs, differences in inhibition of return, or alerting deficits, irrespective of modes of cueing. Conclusion: These results suggest that fundamental orienting and alerting functions might be intact in PD, with challenges emerging only if additional cognitive processes, including those related to motor preparation, are required to utilize cue information. (PsycInfo Database Record (c) 2024 APA, all rights reserved)

Neuropsychology - Vol 38, Iss 8