Search Results (197)

Background/Objectives: Specific Learning Disorders are lifelong neurodevelopmental conditions that persist in adulthood, yet research has traditionally focused on children. In adults, there is significant heterogeneity in cognitive profiles and a lack of consensus on how to operationalize these disorders. This study aims to map the variability in cognitive functioning in university students with Specific Learning Disorders and investigate whether cognitive profiles differ across diagnostic categories and comorbidities. Methods: A retrospective analysis was conducted on the clinical documentation of 166 university students with a diagnosis of Specific Learning Disorders. Participants were categorized into three subgroups: predominant reading disorder, predominant arithmetic disorder, and mixed learning disorder. Cognitive functioning was assessed using Wechsler scales indices. Data were analyzed using linear mixed-effects models and Latent Profile Analysis. Results: Across the sample, reasoning abilities were significantly higher than cognitive efficiency, with working memory consistently emerging as a core weakness. The mixed-disorder group exhibited the lowest cognitive scores and the greatest working memory deficits. Latent Profile Analysis identified two distinct latent subgroups: a “Low Profile” characterized by weaker working memory and a “High Profile” characterized by stronger reasoning and balanced efficiency. Diagnostic labels were only partially aligned with these profiles; while the mixed-disorder group was overrepresented in the “Low Profile,” substantial intra-individual variability existed across all diagnostic categories. Conclusions: The findings suggest that traditional categorical labels for Specific Learning Disorders have limited explanatory power in adulthood, given the high heterogeneity of cognitive functioning. Cognitive weaknesses, particularly in working memory, persist even in high-achieving university students. Clinical and educational support should shift from a label-based approach toward a dimensional, profile-based model to better address the unique strengths and vulnerabilities of adults with Specific Learning Disorders. Full article

Background/Objectives: The preschool period is critical for neurodevelopment, yet evidence investigating fortified formula’s effect and potential microbiota–gut–brain axis mechanisms in this age group is limited. To evaluate fortified formula milk’s effect on neurodevelopment and explore potential microbiota–gut–brain axis mechanisms in preschool children. Methods: In this 9-month cluster-randomized, double-blind, controlled trial, 120 healthy children aged 3–6 years from four kindergarten classes were stratified by grade and randomly allocated (1:1) to receive either multi-nutrient fortified formula (intervention, n = 60) or standard control milk (n = 60). Neurocognitive function was assessed using the Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV). Safety was evaluated through anthropometry and blood biochemistry. Gut microbiota (16S rRNA sequencing) and fecal metabolomes (untargeted LC-MS) were analyzed at baseline and 9 months. Results: The intention-to-treat (ITT) analysis showed no significant difference in Full Scale Intelligence Quotient (adjusted mean difference: 1.05 points; 95% CI: −1.42, 3.52; p = 0.400). However, the intervention group significantly improved the Processing Speed Index (adjusted mean difference: 5.91 points; 95% CI: 1.88, 9.93; p = 0.004), increased gut microbial alpha diversity (Shannon index) and Bifidobacterium abundance. Metabolomic analysis revealed elevated fecal 2-hydroxybutyric acid (2-HB), a marker of propanoate metabolism. Increases in both Bifidobacterium and 2-HB levels showed a positive association with PSI improvement (both p < 0.05). All children maintained normal growth and safety parameters. Conclusions: Fortified formula milk improved processing speed in preschoolers, a benefit associated with gut ecosystem modulation characterized by Bifidobacterium enrichment and upregulated microbial propanoate metabolism. These results offer preliminary evidence for the role of the microbiota–gut–brain axis in nutritional cognitive programming during early childhood. (Clinical Trial Registry: ChiCTR2400084211). Full article

Intelligence test batteries are a common tool in psychological assessment. Their results can have a large impact on an individual’s life, especially for children and adolescents. Despite this, uncertainty remains as to what extent these results are dependent on the test battery used. Two commonly used intelligence test batteries for children and adolescents in German speaking countries are the WISC-V and the AID 3. This study aimed to investigate the degree of comparability between the two test batteries in terms of their resulting scores, subtest content and test profiles in a mathematically gifted sample. A total of 36 children and adolescents (aged M = 12.89 years, SD = 0.58) completed all subtests of both test batteries. Results revealed that most IQ measures did not differ significantly between the two test batteries for this sample. The correlations of the subtests revealed a structure with four main nodes that was in line with previous factor analytical studies. The standard deviations of the $\tau$-adjusted test scores within test profiles were not significantly different; however, significantly higher ranges were found in the AID 3. Results indicate higher IQ scores on the WISC-V, differential validity for factor structures, and methodological benefits of adaptive testing with the AID 3, particularly in gifted samples. Despite subtest overlaps, composite scores diverge and require individualized interpretation. Full article

Background/Objectives: Attention-Deficit/Hyperactivity Disorder (ADHD) shows substantial cognitive heterogeneity, complicating individualized clinical formulation. This study examined whether Cognitive Disengagement Syndrome (CDS), anxiety, and ADHD symptom severity are associated with memory functions and visuospatial skills in children with ADHD. Methods: The sample included 120 children aged 6–12 years with ADHD (ADHD + CDS: n = 40; ADHD-only: n = 80). Memory was assessed with the Oktem Verbal Memory Processes Test (OVMPT) and Wechsler Memory Scale–Visual Reproduction (WMS–VR), and visuospatial skills with WISC-IV Block Design and Judgment of Line Orientation (JLO). ADHD symptoms were rated using combined parent–teacher Turgay-Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-Based Disruptive Behavior Disorders Scale (T-DSM-IV-S) scores; CDS symptoms with the Barkley Child Attention Scale; and anxiety with the SCARED-Child Form. Group comparisons, correlation analyses, and multivariable linear regression models were conducted. Results: The ADHD + CDS group performed worse on WISC-IV Block Design than the ADHD-only group (p = 0.005). In the ADHD + CDS group, inattention severity showed a strong negative association with WMS–VR short-term memory (r = −0.560, p < 0.001). In the ADHD-only group, inattention severity was negatively associated with OVMPT Spontaneous Recall (ρ = −0.319, p = 0.004) and JLO total score (ρ = −0.348, p = 0.002). Anxiety severity in the ADHD-only group was positively associated with OVMPT Total Learning (ρ = 0.350, p = 0.001), Highest Learning (ρ = 0.370, p = 0.001), and WMS–VR short-term memory (ρ = 0.304, p = 0.006). In regression analyses, the presence of CDS independently and negatively predicted WMS–VR short-term memory (β = −0.187, p = 0.018) and Block Design performances (β = −0.226, p = 0.016). Inattention symptom severity was also independently and negatively associated with Block Design performance (β = −0.243, p = 0.013). Conclusions: CDS status and symptom dimensions contribute to cognitive variability in pediatric ADHD, with CDS showing independent associations with timed visuospatial construction and short-term visual memory. Inattention severity emerged as a robust dimensional predictor of cognitive inefficiency across domains, supporting the clinical utility of symptom-based cognitive profiling in ADHD diagnostic evaluations. In addition, mild anxiety symptoms demonstrated meaningful associations with some learning and memory performances within the ADHD-only group, indicating that affective factors may modulate cognitive outcomes in ADHD. Taken together, these findings support considering CDS status and symptom dimensions jointly when characterizing cognitive variability in ADHD. Full article

Background: Although there is substantial research into individual nutrients during pregnancy, such as folate, iron, and vitamin D, little is known about the impact of mixtures of essential nutrients. We investigated the associations between mixtures of maternal essential minerals and vitamin concentrations and child cognition and executive functions at age 7. Methods: Data from 348 mother–child pairs in the Growing up in Singapore Towards Healthy Outcomes birth cohort with both plasma nutrient and neurodevelopmental outcome data were used. Gestational fasting plasma samples between 26 and 28 weeks of gestation were analyzed for 10 essential minerals and 12 B and D vitamers. Child cognition and executive functions at 7 years were assessed using the Wechsler Abbreviated Scale of Intelligence 2nd Edition (WASI-II) [n = 331] and the Behavior Rating Inventory of Executive Function 2nd Edition (BRIEF-2) [n = 348], respectively. Generalized weighted quantile sum regression (gWQS) was used to investigate the associations between nutrient mixtures and child cognitive executive function scores. Single-nutrient analysis using covariate-adjusted multivariable regressions was performed as a sensitivity analysis. Results: A one-quartile increase in the positively weighted nutrient mixture index was associated with higher block design T-scores (β = 2.17, 95% CI: 0.03, 4.31). Additionally, the negatively weighted mixture was associated with lower block design (β = −2.25, 95% CI: −4.92, 0.41, p = 0.02) and perceptual reasoning (β = −1.94, 95% CI: −5.17, 1.29, p = 0.04) scores in boys only. We found no association between the nutrient mixture and BRIEF-2 subscale T-scores. Conclusions: In this study, we found that a positively weighted nutrient mixture index of maternal gestational minerals and vitamins was associated with a greater ability in children to analyze and understand abstract visual items. Full article

Background/Objectives: Increasing fruit and vegetable (F&V) intake may benefit children’s neurobehavioral development, but randomized evidence remains limited. We evaluated whether F&V-enriched breakfast improves cognition, attention and mood in primary school children. Methods: We conducted a 12-week class-randomized controlled trial in Shanghai, China. A total of 251 children aged 7–11 years received either a daily F&V-enriched breakfast or a standardized control breakfast with comparable energy provision, both centrally prepared and home-delivered. The primary outcome was change in Full-Scale IQ (FSIQ) measured by the Wechsler Intelligence Scale for Children—Fourth Edition (WISC-IV). Secondary outcomes included WISC-IV composite indices, attention-related behavioral symptoms assessed by the Parent Symptom Questionnaire, and mood by the Profile of Mood States—Brief. Analyses followed the intention-to-treat principle with multiple imputation. Results: Among 282 children screened, 251 were randomized, with 243 completing post-intervention assessments and 230 completing follow-up. The adjusted mean change in FSIQ did not differ between groups (mean difference = −0.63; 95% CI −5.15~3.89; p = 0.807). No statistically significant between-group differences in change were observed for other cognitive indices, behavioral symptoms, or overall mood disturbance. Exploratory analyses suggested a greater reduction in fatigue scores among children aged ≤8 years in the intervention group compared with controls. Dietary assessment confirmed higher dietary fiber and carotene intakes in the intervention group at week 12. No intervention-related adverse events were reported. Conclusions: An F&V-enriched breakfast improved dietary quality but did not produce measurable between-group improvements in cognitive or neurobehavioral outcomes over 12 weeks. Exploratory age-specific findings warrant further investigation. Full article

Background/Objectives: Posterior fossa tumors (PFTs) often require radiotherapy which may damage both cortical and subcortical brain tissue. We examined voxel-based and region-based gray matter volume (GMV) alterations and explored their relation to cognitive functioning. Methods: Using T1-weighted MR imaging, intelligence scores from the Wechsler Adult Intelligence Scale-IV (WAIS-IV), and domain scores for language, learning, and memory, complex attention and cognitive flexibility were investigated in 18 of 21 assessed PFT survivors and 21 matched controls. GMV was quantified with voxel-based and region-based volumetry, compared among groups (controls versus survivors, irradiated versus non-irradiated survivors), and correlated with cognitive performance. Results: Survivors showed reduced GMV in two voxel-based clusters, located in the left occipital fusiform area and the left pallidum. Region-based analyses showed lower GMV in survivors located in subcortical areas, while higher GMV was observed in the left inferior temporal region. Survivors who received craniospinal radiation exhibited reductions in GMV in bilateral thalami, right ventral diencephalon, and central corpus callosum, and higher GMV in the bilateral middle temporal regions. Compared to controls, survivors scored lower for all cognitive domains, except for complex attention and cognitive flexibility. Amongst survivors, the GMV of the bilateral thalami and right ventral diencephalon correlated positively with working memory. Conclusions: Overall, PFT survivors demonstrated both alterations in GMV and cognitive functioning, with the most pronounced GMV deviations found in those treated with craniospinal radiation. Reduced GMV was associated with poorer cognitive performance. Full article

Autism spectrum disorder (ASD) and intellectual disability (ID) frequently coexist and share heterogeneous cognitive manifestations, yet their specific performance patterns on Wechsler scales remain poorly systematized. This meta-analysis synthesized data from 31 studies using the WISC-IV, WISC-V, WAIS-III, and WAIS-IV to compare cognitive index profiles in individuals with ASD, ID and ASD+ID. Standardized mean differences (Hedges’ g) were calculated using random-effects models, adopting a normative reference of mean 100 and SD 15. Results showed a distinct profile for ASD, with greater impairments in the Processing Speed Index (PSI) and Working Memory Index (WMI), while the Vocabulary Comprehension Index (VCI), Perceptual/Fluid Reasoning Index (PRI/FRI), and Visual Processing Index (VPI) remained close to normative scores. In contrast, ID and ASD+ID exhibited generalized deficits across all indices, with the lowest scores in Full-Scale IQ (FSIQ) and broad effects above g = −2.5. No significant differences emerged between Wechsler versions or age-based test types. Heterogeneity was high in ASD and ID across outcomes, but negligible in ASD+ID due to reduced k. These findings reinforce that ASD presents a specific cognitive pattern, whereas ID and ASD+ID display diffuse impairment, and that Wechsler scales are consistent across versions for identifying these profiles. Full article

Background/Objectives: Children born small for gestational age (SGA) are at increased risk for impaired growth, metabolic disturbances, and neurodevelopmental difficulties. Although previous research has examined cognitive and behavioral outcomes in this population, findings remain inconsistent. Moreover, limited evidence is available regarding the potential effects of recombinant human growth hormone (rhGH) therapy on cognitive development. We aimed to assess cognitive performance, emotional–behavioral functioning, and neonatal predictors of neurocognitive outcomes in term SGA children compared with age- and sex-matched peers born appropriate for gestational age (AGA). We also explored potential differences in cognitive outcomes between rhGH-treated and untreated SGA children. Methods: A total of 18 term SGA children and 23 AGA controls underwent anthropometric measurements, biochemical evaluation, cognitive testing using the Wechsler Intelligence Scale for Children—Fourth Edition (WISC-IV), and behavioral assessment through the Child Behavior Checklist (CBCL). Birth weight, length, and head circumference were analyzed as potential predictors of cognitive performance. Results: SGA children demonstrated significantly lower Intelligence Quotient (IQ) scores than AGA peers, with marked weaknesses in Perceptual Reasoning index (PRI) and Processing Speed index (PSI), while Verbal Comprehension and Working Memory were preserved. They also exhibited higher internalizing behavioral symptoms, whereas externalizing behaviors did not differ between groups. Birth head circumference emerged as a strong predictor of PRI and a modest predictor of PSI. No associations were found between rhGH treatment parameters and cognitive outcomes. Larger longitudinal studies are needed to clarify how early growth restriction affects brain development and cognition and whether GH therapy influences these processes. Full article

Background: Late preterm delivery accounts for approximately 5% of all births. Although there is a growing body of literature recognizing that children born late preterm are at risk for mild neurodevelopmental issues, these children are often excluded from follow-up programs. From a preventive perspective, it could be useful to promote protective factors for child development. Among these, human milk feeding is highly recommended due to its advantages for child health and development. However, there is limited research on the complex interactions between late preterm birth, human milk feeding, and subsequent cognitive and emotional development. This paper aims to explore these interactions. Methods: This study focuses on late preterm children aged 8 to 12 years who are attending school. A trained psychologist conducted assessments of cognitive development using the Wechsler Intelligence Scale for Children-III (WISC-III). Additionally, the family pediatrician gathered neonatal and current growth data, while parents completed the Child Behavior Checklist 6–18 (CBCL) regarding their child’s emotional and behavioral profile. Results: A significant impact of early nutrition on children’s cognitive development was observed, with those fed human or formula milk scoring higher than those in the mixed milk group. Additionally, early feeding, high maternal and low paternal perception of externalizing difficulties significantly predicted children’s cognitive development. Conclusions: The study suggests the potential role of early nutrition and externalizing difficulties in the cognitive development of late preterm children at school age. Therefore, the inclusion of protective factors such as breastfeeding should be encouraged in future research. Full article

The impact of prenatal exposure to trace metal mixtures on children’s neurodevelopment remains debated. Many studies treat all trace metals as a single entity, overlooking the distinct biological roles of essential and toxic metals. This approach may highlight overall exposure but fails to capture their differential effects on neurodevelopment. This study aims to examine the associations between prenatal exposure to essential and toxic metals and children’s cognitive development, focusing on their independent effects. A cohort of 201 mother–infant pairs was analyzed. Maternal urinary metal levels were measured at 12 weeks of gestation, and children’s neurodevelopment was assessed at 4 years using the Wechsler Preschool and Primary Scale of Intelligence and the Developmental Neuropsychological Assessment. Generalized Additive Models (GAM), Restricted Cubic Spline (RCS), and Weighted Quantile Sum (WQS) regression were applied. GAM identified non-linear associations between essential metals (manganese and molybdenum) and cognitive outcomes, including verbal comprehension index (VCI), working memory index, full-scale IQ, and general ability index, which were confirmed by RCS. No non-linear relationships were observed for toxic metals. WQS showed negative associations between toxic metals and VCI (b = −1.07), processing speed index (b = −0.98), vocabulary acquisition index (b = −1.25), and verbal fluency (b = −0.23), mainly driven by cadmium (Cd) and antimony (Sb). Essential metal mixtures were not associated with cognitive outcomes. Prenatal exposure to toxic metals negatively affects children’s cognitive and neuropsychological development. Reducing maternal exposure during pregnancy is essential for protecting offspring development. Full article

Background/Objectives: To characterize functional brain activation during smiling and to assess cognitive profiles in patients with Ochoa (Urofacial) syndrome (UFS). Materials and Methods: In a block-design fMRI paradigm, participants alternated between imitating a smiling emoji and viewing a fixation cross. Images were preprocessed and analyzed in SPM12; Smile > Rest contrasts were tested with a voxelwise threshold of p < 0.001 (uncorrected). Cognitive levels were assessed using age-appropriate Wechsler scales administered by certified psychologists. Results: Six patients (mean age 20 years; 50% female) with genetically/clinically confirmed UFS were included. Smile > Rest elicited robust activation in the supplementary motor area (highest Z = 4.70), insula (largest cluster), dorsal anterior cingulate, primary motor cortex, and frontal eye fields, among others. Five patients completed cognitive testing; Full-Scale IQ ranged 50–74, consistent with mild intellectual disability to borderline intellectual functioning. Conclusions: During voluntary smiling, UFS patients exhibit activation patterns that overlap extensively with those reported in healthy cohorts. Nevertheless, cognitive performance was limited in this sample. Given the rarity of UFS and the small cohort, findings should be interpreted cautiously and validated in multicenter studies. Full article

Background/Objective: The gait pattern of children born very preterm shows gait decrements compared to their full-term peers in dual-task walking. It is essential to identify children at a higher risk for these gait deficits. The aim of this study was to compare spatiotemporal gait variables in preschool-age children born very preterm at risk for developmental coordination disorder (DCD) with those not at risk. Methods: Preschool-age children born < 30 weeks’ gestation. Risk for DCD was defined as (i) ≤16th percentile on the Movement Assessment Battery for Children—Second Edition, (ii) ≥80 on the Wechsler Preschool and Primary Scale of Intelligence-Fourth Edition, and (iii) without cerebral palsy. Spatiotemporal gait variables and variability were assessed using GAITRite^® during preferred speed, cognitive and motor dual-task, and tandem conditions. Variables included speed (cm/s), step time (s), cadence (steps/min), step length (cm), base of support (BOS; cm), and single and double support time (%gait cycle). Results: Of 111 children who were assessed, 26 children were classified as at risk for DCD. Most gait variables were similar between groups at preferred speed walking. Children at risk for DCD had wider BOS and shorter single support time in motor dual-tasking (mean difference [MD] = 0.86 cm, 95% confidence interval [CI] 0.10, 1.61; MD = −1.77%, 95% CI −3.36, −0.19) compared to those not at risk. Similarly, wider BOS and higher cadence were found when tandem walking (MD = 0.63 cm, 95% CI 0.07, 1.20; MD = 0.63 steps/min, 95% CI 0.07, 1.20). Conclusions: Children born very preterm at risk for DCD had poorer walking performance than those not at risk for DCD at preschool age, especially during dual-task situations. Clinicians may incorporate complex gait assessments into early evaluations to detect subtle impairments in children. Future research is needed to investigate the impact of gait variability on children’s daily lives and participation in sports activities. Full article

Attention Deficit Hyperactivity Disorder (ADHD) is a prevalent neurodevelopmental disorder characterised by cognitive and behavioural impairments. This study aimed to identify cognitive patterns associated with ADHD in a sample of 719 children and adolescents (363 with ADHD and 356 controls) assessed using the Wechsler Intelligence Scale for Children—Fourth Edition (WISC-IV). Compared to controls, the clinical group exhibited significantly lower scores in the Working Memory Index (WMI), Processing Speed Index (PSI), and Cognitive Proficiency Index (CPI). No significant group differences were found in Verbal Comprehension (VCI) or Perceptual Reasoning (PRI) after controlling for age and sex. Factorial MANOVA results revealed that WMI, PSI, and CPI deficits remained stable across age groups and were more pronounced in males. Females with ADHD outperformed males in PSI. A binary logistic regression model including WISC-IV core indices classified VCI, PRI, WMI, and PSI with a Nagelkerke R² of 0.44 as significant predictors of group membership, indicating that lower scores in WMI and PSI, and higher scores in VCI and PRI, increased the likelihood of ADHD classification. These findings reinforce the use of the WISC-IV as a complementary tool in the cognitive characterisation and clinical assessment of ADHD in youth. Full article

Background/Objectives: This study investigates the efficacy of working memory training (WMT) using the dual N-back (DNB) task on cognitive performance in young adults with Attention-Deficit/Hyperactivity Disorder (ADHD). Methods: Over the course of at least 18 daily sessions conducted within one month, 106 participants (33 non-medicated ADHD, 42 medicated ADHD, and 45 controls) were randomly assigned to either a fixed dual 1-back (FD1B) training condition or an adaptive DNB condition, wherein the N-back level increased following successful completion of each trial block. Cognitive performance was assessed pre- and post-intervention using the Wechsler Adult Intelligence Scale–Fourth Edition (WAIS-IV) Working Memory Index (WMI) and the Corsi Block-Tapping Task. Results: A mixed-design ANOVA revealed significant improvements in DNB performance across all groups, with the adaptive training condition producing larger gains (e.g., a 204.6% improvement in controls, Cohen’s $d=1.85$). WAIS-IV WMI scores—particularly the Digit Span Backward subtest—also improved significantly post-training, with greater effect sizes in the adaptive condition ($d=0.46$) than in FD1B ($d=0.27$). Corsi performance showed very modest gains, showing a surprising tendency to be more associated with the FD1B condition than the adaptive condition. Control participants outperformed the medicated ADHD group on WAIS-IV subtests, although no significant differences emerged between medicated and non-medicated ADHD participants. Correlational analyses indicated task-specific training effects, with adaptive training enhancing associations between DNB and Corsi performance in both controls ($r=0.60$) and medicated ADHD participants ($r=0.51$). Conclusions: This study demonstrates that dual N-back training improves verbal working memory in young adults with ADHD, specifically in a sample without psychiatric comorbidities. Transfer benefit to visuospatial domains appears limited and may not generalize to adolescents, older adults, or individuals with complex clinical profiles. The results underscore the importance of tailoring training protocols to maximize cognitive outcomes across different domains. Full article