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Intelligence profiles in autism have been characterized by great variability. The questions of how autistic children's intelligence changes over time, and what factors influence these changes deserve study as part of efforts to document child autism profiles, but also because the relationship between intellectual functioning and children's background characteristics is poorly understood, particularly in a longitudinal context. A total of 39 autistic children and 39 age‐matched neurotypical children (5–9 years old) completed two IQ assessments at preschool age and up to 4 years later. Repeated‐measures analyses assessed longitudinal changes in the children's verbal (VIQ), performance (PIQ), and full‐scale IQ (FSIQ) at group level. We further sought to identify clusters with distinct profiles in each group by adopting an unsupervised K‐means clustering approach, and detect possible between‐subgroup differences in terms of children's socioeconomic status and autism severity. The largest cluster in the autistic group was composed of children whose PIQ significantly dropped at follow‐up, while the second largest cluster improved in all quotients; the smallest cluster, wherein children had more highly educated mothers than the rest of the clusters, was characterized by large improvement in VIQ. For the neurotypical children, there was a two‐cluster division; the majority of them improved in the three quotients, while very few dropped in PIQ at follow‐up. The relation between socioeconomic status and IQ changes was significant for both groups. The findings demonstrate both the complexity of intelligence changes in autism and the need to view this complexity through the lens of the children's socioeconomic diversity. Lay Summary: The development of autistic children's intellectual skills is characterized by great variability which remains poorly understood. In the current study, we investigated the developmental trajectories of verbal IQ, performance IQ, and full‐scale IQ scores of autistic children who were first assessed on their intellectual functioning skills at preschool age and were followed‐up at the age of 9. Results showed distinct profiles of IQ changes in the autistic group which were significantly affected by the children's socioeconomic background. The study demonstrates that a dimensional perspective to IQ in autism that takes into consideration children's socioeconomic background might better inform our understanding of how their intelligence develops over time. [ABSTRACT FROM AUTHOR]

Background: Sufficient sleep during childhood is important for cognitive functions such as learning and successful school performance. This study aimed to investigate the effects of sleep duration on the intelligence quotient (IQ) of 6-year-old children and aimed to analyze whether these effects differed by sex. Methods: The IQ of 538 6-year-old Korean participants from the cohort study, "The Environment and Development of Children," was measured during follow-up using the Korean Educational Developmental Institute's Wechsler Intelligence Scale for Children. The total, verbal, and performance IQ scores were evaluated. The relationship between sleep duration and IQ scores after adjusting for maternal age, maternal educational level, maternal occupation, maternal IQ, exposure to secondhand smoking, gestational age, and monthly age and birth season was also assessed. Results: Longer sleep duration was significantly associated with improved verbal IQ measures (β 0.55; p value 0.030). After stratifying participants by sex, a significant association was observed between sleep duration and total, verbal, and performance IQ scores in boys (total IQ 2.49, p value 0.012; verbal IQ 0.75, p value: 0.037; performance IQ 0.73, p value 0.048), but not in girls. Conclusions: The results indicated that only boys show a significant association between IQ scores and sleep duration. These findings support the hypothesis that sleep duration is associated with IQ, in a sex dependent manner. Future studies are needed for a thorough evaluation of the connection between sleep duration and health outcome in young children. [ABSTRACT FROM AUTHOR]

Aim: In this study, we examined (1) the presence of abnormally low scores (below 10th percentile) in various visual motion perception aspects in children with brain damage, while controlling for their cognitive developmental delay; (2) whether the risk is increased in comparison with the observation and expectation in a healthy control group and healthy population. Methods: Performance levels of 46 children with indications of brain damage (Mage = 7y4m, SD = 2y4m) on three visual motion perception aspects (global motion, motion speed, motion-defined form) were evaluated. We used developmental age as entry of a preliminary reference table to classify the patient's performance levels. Then we compared the percentages of abnormally low scores with percentages expected in the healthy population using estimated base rates and the observed percentages in the control sample (n = 119). Results: When using developmental age as reference level, the percentage of low scores on at least one of the three tasks was significantly higher than expected in the healthy population [19/46, 41% (95%CI: 28–56%), p = 0.03]. In 15/19 (79% [95%CI: 61–97%] patients only one aspect of motion perception was affected. Four patients performed abnormally low on two out of three tasks, which is also higher than expected (4/46, 8.7%, 95%CI: 2.4–20.8% vs. 2.1%; z = 2.61, p < 0.01). The observed percentages in the patient group were also higher than found in the control group. Interpretation: There is some evidence that children with early brain damage have an increased risk of isolated and combined motion perception problems, independent of their performance IQ. [ABSTRACT FROM AUTHOR]

• The unique relationships of cheating to verbal vs. performance IQ were investigated. • Thirty-two percent of 5-year-old children cheated in a guessing game. • Verbal IQ scores had a unique and negative correlation with children's cheating. • The higher Verbal IQ scores, the lower children's tendency to cheat. • Neither Performance IQ nor Total IQ scores were uniquely correlated with cheating. Cheating is a pervasive unethical behavior. Existing research involving young children has mainly focused on contextual factors affecting cheating behavior, whereas cognitive factors have been relatively understudied. This study investigated the unique role of verbal and performance intelligence on young children's cheating behavior (N = 50; mean age = 5.73 years; 25 boys). Bootstrapping hierarchical logistic regression showed that children's Verbal IQ scores were significantly and negatively correlated with their cheating behavior above and beyond the contributions of age, gender, and Performance IQ scores. Children with higher Verbal IQ scores were less inclined to cheat. However, neither children's Performance IQ nor their Total IQ scores had a significant and unique correlation with cheating. These findings suggest that intelligence plays a significant role in children's cheating but that this role is limited to verbal intelligence only. In addition, this study highlights the need for researchers to go beyond the contextual factors to study the early development of cheating behavior. [ABSTRACT FROM AUTHOR]

Intelligence profiles in autism have been characterized by great variability. The questions of how autistic children's intelligence changes over time, and what factors influence these changes deserve study as part of efforts to document child autism profiles, but also because the relationship between intellectual functioning and children's background characteristics is poorly understood, particularly in a longitudinal context. A total of 39 autistic children and 39 age-matched neurotypical children (5-9 years old) completed two IQ assessments at preschool age and up to 4 years later. Repeated-measures analyses assessed longitudinal changes in the children's verbal (VIQ), performance (PIQ), and full-scale IQ (FSIQ) at group level. We further sought to identify clusters with distinct profiles in each group by adopting an unsupervised K-means clustering approach, and detect possible between-subgroup differences in terms of children's socioeconomic status and autism severity. The largest cluster in the autistic group was composed of children whose PIQ significantly dropped at follow-up, while the second largest cluster improved in all quotients; the smallest cluster, wherein children had more highly educated mothers than the rest of the clusters, was characterized by large improvement in VIQ. For the neurotypical children, there was a two-cluster division; the majority of them improved in the three quotients, while very few dropped in PIQ at follow-up. The relation between socioeconomic status and IQ changes was significant for both groups. The findings demonstrate both the complexity of intelligence changes in autism and the need to view this complexity through the lens of the children's socioeconomic diversity., (© 2024 The Authors. Autism Research published by International Society for Autism Research and Wiley Periodicals LLC.)

In patients with cortical lesions, the structure of intelligence has never been studied as a function of age at lesion onset and presence vs absence of lesional epilepsy over the life span. Method Two thousand one hundred eighty-six cases were assembled bearing unilateral cortical lesions occurring at all ages (1301 with seizures) with postlesion verbal intelligence quotient (IQ) (VIQ) and performance IQ (PIQ). Results Global IQ significantly and constantly decreased as a function of age at lesion onset in the cases without epilepsy, and increased in the cases with epilepsy. Beyond the lesion onset age of 12 years, VIQ was significantly higher than PIQ in the cases without epilepsy, and lower in the cases with epilepsy. The VIQ/PIQ × lesion-side interaction indicative of hemispheric specialization increased significantly linearly with age at lesion onset in the patients without epilepsy but ceased to progress at the lesion-onset age of 30 years and beyond in the cases with epilepsy. Conclusion Postlesion global IQ, the difference between VIQ and PIQ, and the laterality index all vary significantly as a function of age at lesion onset. In addition, these changes over the life span are all quite different between cases with and without epilepsy. [ABSTRACT FROM AUTHOR]

Locus of control (LOC) is a measure that identifies the likelihood as to whether an individual considers what happens to him is largely a matter of luck or fate (known as externally oriented) or whether it is something that the individual can influence (internality). Here we have used data collected as part of the Avon Longitudinal Study of Parents and Children (ALSPAC) to determine the associations between the mothers’ LOC orientation before the birth of the child and her child’s cognition measured at age 8. Using results from 6801 children we show that maternal internal LOC is associated with increased ability in offspring IQ, as measured using the WISC, with children of internally oriented mothers having an advantage of approximately 7 IQ points at age 8. As a sensitivity analysis we used the IQ test results of a sample of 986 preschool children tested using the WPSSI at age 4. A similar advantage was found among the offspring of the internally oriented mothers. We investigated mechanistic explanations for these results firstly by determining the extent to which three separate sets of factors known to be influenced by the LOC orientation might explain these findings. We showed that (a) perinatal life-style exposures, (b) parenting attitudes and strategies and (c) socio-economic circumstances, largely explain the mechanism through which the internality of the mother influences the cognition of the child. Similar effects were found using the smaller sample tested at age 4. The results indicate that efforts made to foster internality in adolescents and young adults prior to parenthood may result in improvements in the cognitive development of the next generation. Intervention studies are urgently needed.

Background: The presence of an association between age at the onset of puberty and intelligence quotient (IQ) in young adolescents remains controversial. The aim of this study was to explore the association between age at menarche and performance IQ scores of young female adolescents in Bangkok, Thailand.Methods: A cross-sectional study was conducted among 537 students aged 11-15 years attending primary and secondary schools in the Dusit district of Bangkok, Thailand. The participants were selected based on two-step stratified sampling. Age at menarche and health and socioeconomic status were determined using a self-report questionnaire completed by participants. Performance IQ scores were determined using the Standard Progressive Matrices intelligence test (Thai version) administered by registered clinical psychologists.Results: Of the 537 participants, 0.4 had reached menarche at 8 years of age, 1.9 at 9 years, 10.1 at 10 years, 36.1 at 11 years, 37.6 at 12 years, 10.4 at 13 years, 3.4 at 14 years, and 0.2 % at 15 years. Age at menarche was inversely correlated with performance IQ (Pearson correlation -0.087, p = 0.047). The regression equation predicting performance IQ by age at menarche was performance IQ = 128.06 - 1.16*age at menarche (R (2)  = 0.008). In univariate analysis, performance IQ was inversely correlated with age at menarche, body mass index (BMI), time spent watching television, and time sleeping, but was directly correlated with maternal age at birth (all p < 0.05). In multivariate analysis, age at menarche and BMI remained significantly inversely correlated with performance IQ (p < 0.05), while maternal age at birth was directly correlated with performance IQ. The model consisting of age at menarche, BMI, and maternal age at birth best predicted performance IQ.Conclusion: After adjusting for confounders, multiple regression analysis showed that age at menarche and BMI of young female adolescents living in the Dusit district of Bangkok, Thailand, were inversely correlated with performance IQ, whereas maternal age at birth was directly correlated with performance IQ. [ABSTRACT FROM AUTHOR]

The present study analyses the effect of mantra chanting on the performance IQ of 8-13 years old students in Dehradun. In the study it has been hypothesised that the performance IQ(PIQ*) of children will be enhanced with 15 minutes of mantra chanting when practiced for 30 days daily. For this experimental study 15 students were studied by using four performance tests of Malm's intelligence battery for children (an Indian adaptation of Weischler's Intelligence battery for children). The pre and post test results are analysed with't1 test. Performance sub-tests are non-verbal in nature and the sum of four Transient quotients gives performance IQ(PIQ*). The test of significance reveals a significant result p= 0.01% and t=3.339. The frequency of repetition of the mantra also increased with proficiency. The critical value p<0.01%, t =2.74 test shows significance difference in pre and post WASP frequency analysis. It establishes the fact that 15 min. of mantra chanting is effective in enhancing the performance IQ. [ABSTRACT FROM AUTHOR]

The Wechsler abbreviated scale of intelligence (WASI) was developed to rapidly assess intelligence, providing Verbal, Performance, and Full Scale IQ scores. This study aimed to investigate whether part of the standardization sample data from the Brazilian version of the instrument fits the two-factor model. Confirmatory factor analysis was conducted with data from 534 participants, average age 28.78 years (SD=22.07), and 51.5% female. The analyses were performed considering the total sample, the children and adolescents sample and the adult sample. Results indicate that the two-factor model fits the analyzed sample. Considerations are presented regarding the internal validity and conceptual proposal of the instrument. [ABSTRACT FROM AUTHOR]

Abstract: Intelligence quotient (IQ) scores tend to remain stable across the lifespan. Nevertheless, in some healthy individuals, significant decreases or increases in IQ have been observed over time. It is unclear whether such changes reflect true functional change or merely measurement error. Here, we applied surface-based corticometry to investigate vertex-wise cortical surface area and thickness correlates of changes in Full Scale IQ (FSIQ), Performance IQ (PIQ) and Verbal IQ (VIQ) in a representative sample of children and adolescents (n=188, mean age=11.59years) assessed two years apart as part of the NIH Study of Normal Brain Development. No significant associations between changes in IQ measures and changes in cortical surface area were observed, whereas changes in FSIQ, PIQ, and VIQ were related to rates of cortical thinning, mainly in left frontal areas. Participants who showed reliable gains in FSIQ showed no significant changes in cortical thickness on average, whereas those who exhibited no significant FSIQ change showed moderate declines in cortical thickness. Importantly, individuals who showed large decreases in FSIQ displayed the steepest and most significant reductions in cortical thickness. Results support the view that there can be meaningful cognitive ability changes that impact IQ within relatively short developmental periods and show that such changes are associated with the dynamics of cortical thickness development. [Copyright &y& Elsevier]

Abstract: Clinical theory predicts that individuals high in psychopathic traits possess average or above average intelligence; however findings in adult and child samples have been mixed. The present study aimed to investigate (1) the relationship between verbal and nonverbal intelligence and the three dimensions of psychopathy (callous-unemotional (CU) traits, narcissism, impulsivity); and (2) whether these dimensions moderate the association between verbal and nonverbal intelligence and the severity of antisocial behavior. Participants were 361 adolescents aged 9–18 years (68% boys) and their parents, drawn from four samples with different levels of risk for antisocial behavior. Families were disadvantaged and 25% were from an ethnic minority. Verbal intelligence was unrelated to parent-reported CU traits, narcissism or impulsivity after controlling for gender, sociodemographic disadvantage, sample, antisocial behavior and hyperactivity. Narcissism, but not CU traits or impulsivity, was significantly related to lower nonverbal IQ. None of the three psychopathic trait dimensions moderated the relationship between verbal or nonverbal IQ and antisocial behavior. CU traits, narcissism, hyperactivity and inclusion in the very high or high risk samples were significantly related to more severe antisocial behavior. Results contradict the widely held view that psychopathic traits are associated with better than average verbal or nonverbal intelligence. [Copyright &y& Elsevier]

Background: Despite the body of literature that links anemia with poorer cognition in children and the evidence that the severity of the effects of anemia on children's cognition vary in different populations, few studies have investigated the effects of anemia on the cognitive development of Chinese children. Methods: This longitudinal cohort included 171 children from a developing region of China. Hemoglobin (Hb) and iron levels were taken when the children were 4 years old. At age 6, the children's cognition was tested with the Chinese Wechsler Preschool and Primary Scale of Intelligence. Psychosocial information was also used in analyses. Results: Results showed that the children who had low Hb levels had significantly lower scores in performance IQ (PIQ), but not verbal IQ. Although blood Fe levels were not shown to moderate the link between Hb levels and IQ, we found children who performed the best on IQ tests exhibited low iron levels concurrent with high Hb levels, whereas the group who performed the worst exhibited high iron but low Hb levels. We also found that psychosocial adversity did not differ significantly between children who had normal or low Hb levels, although the effect of Hb on PIQ became only suggestive after controlling for psychosocial adversity, therefore the correlation is not causal but only a suggestive association. Conclusion: Our findings are in agreement with literature on the negative effects of anemia on children's cognition and point to the possibility that the portions of the brain associated with PIQ components are particularly affected by low Hb during crucial periods of development. [ABSTRACT FROM AUTHOR]

The longitudinal stability of IQ is well-documented as is its increasing heritability with age. In a longitudinal twin study, we addressed the question to what extent heritability and stability differ for full scale (FSIQ), verbal (VIQ), and performance IQ (PIQ) in childhood (age 9-11 years), and early adolescence (age 12-14 years). Genetic and environmental influences and correlations over time were evaluated in an extended twin design, including Dutch twins and their siblings. Intelligence was measured by the Wechsler Intelligence Scale for children - Third version (WISC III). Heritability in childhood was 34% for FSIQ, 37% for VIQ, and 64% for PIQ, and increased up to 65%, 51%, and 72% in early adolescence. The influence of common environment decreased between childhood and early adolescence from explaining 43% of the phenotypic variance for FSIQ to 18% and from 42% for VIQ to 26%. For PIQ common environmental influences did not play a role, either in childhood or in early adolescence. The stability in FSIQ and VIQ across the 3-year interval (r(p)) was .72 for both measures and was explained by genetic and common environmental correlations across time (FSIQ, r(g) = .96, r(c) = 1.0; VIQ, r(g) =.78, r(c) = 1.0). Stability of PIQ (r(p) =.56) was lower and was explained by genetic influences (r(g) = .90). These results confirm the robust findings of increased heritability of general cognitive abilities during the transition from childhood to adolescence. Interestingly, results for PIQ differ from those for FSIQ and VIQ, in that no significant contribution of environment shared by siblings from the same family was detected. [ABSTRACT FROM AUTHOR]

Objective: Converging evidence suggests a role for the anterior cingulate cortex (ACC) in the pathophysiology of anorexia nervosa (AN). This study sought to determine whether ACC volume was affected by starvation in active AN and, if so, whether this had any clinical significance. Method: Eighteen patients with active AN and age- and gender-matched normal controls underwent magnetic resonance imaging (MRI). Sixteen patients (89%) with AN had intelligence quotients (IQ) testing at intake, 14 (78%) had repeat MRIs after weight normalization, and 10 (56%) had outcome data at 1-year posthospitalization. Results: Right dorsal ACC volume was significantly reduced in active AN patients versus controls and was correlated with lower performance IQ. While ACC normalization occurred with weight restoration, smaller change in right dorsal ACC volume prospectively predicted relapse after treatment. Conclusion: Reduced right dorsal ACC volume during active AN relates to deficits in perceptual organization and conceptual reasoning. The degree of right dorsal ACC normalization during treatment is related to outcome. © 2008 by Wiley Periodicals, Inc. Int J Eat Disord 2008 [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the verbal and performance intelligence of young Mandarin-speaking cochlear implant users with the Wechsler Intelligence Scale for Children (WISC). We also analyzed whether related factors helped develop verbal and performance IQs. We studied 60 children implanted with Nucleus 24 devices; the children represented a consecutive sample of every implantee aged 6 or older from 2002 to 2006. All subjects had 1 year to 8 years and 7 months of implant experience. Five children with known neurological, developmental delay and multiple handicaps were excluded. Intellectual functions were evaluated using the Mandarin version of the WISC-III, which includes 5 subsets for verbal IQ (information, comprehension, similarities, arithmetic and vocabulary) and 5 subsets for performance IQ (picture completion, picture arrangement, block design, object assembly and coding). After conversion, we found that the mean verbal IQ was 85.1 ± 19.9 (range 56–133), and the mean performance IQ was 99.2 ± 15.9 (range 61–131). The distribution of verbal IQ was significantly different from that of the hearing population. A much larger proportion (32%) falls into the category of ‘intellectual deficiency’ and a relatively smaller proportion in the ‘average’ and ‘above average’ level. As for performance IQ, the distribution was not significantly different from the norms. Regarding the possibly related factors, univariate and multivariate linear regression showed that the verbal IQ was significantly affected by gender (female > male, p = 0.004), side of implantation (bilateral > left > right, p = 0.017) and two speech test scores (PB score, p = 0.036; sentence, p = 0.002), but not by age at implantation (p = 0.621) or length of implant usage (p = 0.480). Only a moderate correlation (r = 0. 49) was found between verbal and performance IQ. In conclusion, we have demonstrated that the performance IQ for the cochlear implant users is not different from their counterparts with normal hearing. However, the distribution of verbal IQ significantly shifts to the left. Our findings suggest that the verbal IQ test may just be another measurement of spoken language outcomes or learning skills and therefore may not represent the ‘true intelligence’ of these cochlear implant users. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: The corpus callosum is the largest commissural white matter pathway that connects the hemispheres of the human brain. In this study, diffusion tensor imaging (DTI) was performed on subject groups with high-functioning autism and controls matched for age, handedness, IQ, and head size. DTI and volumetric measurements of the total corpus callosum and subregions (genu, body and splenium) were made and compared between groups. The results showed that there were significant differences in volume, fractional anisotropy, mean diffusivity, and radial diffusivity between groups. These group differences appeared to be driven by a subgroup of the autism group that had small corpus callosum volumes, high mean diffusivity, low anisotropy, and increased radial diffusivity. This subgroup had significantly lower performance IQ measures than either the other individuals with autism or the control subjects. Measurements of radial diffusivity also appeared to be correlated with processing speed measured during the performance IQ tests. The subgroup of autism subjects with high mean diffusivity and low fractional anisotropy appeared to cluster with the highest radial diffusivities and slowest processing speeds. These results suggest that the microstructure of the corpus callosum is affected in autism, which may be related to nonverbal cognitive performance. [Copyright &y& Elsevier]

This study tested the Eysenck/Jensen ‘speed of neural processing’ theory of general ability by examining the relationship between general mental ability and speed of performing a simple, repetitive movement. Seventy psychology students were tested for intelligence using Raven’s Advanced Progressive Matrices and the Wechsler Adult Intelligence Scale-III. Motor speed was assessed by means of a tapping task in which two fingers tapped alternately. The expected positive correlations between speed scores and cognitive measures were obtained, with significant associations demonstrated between tapping speed and traditional Full-scale IQ, Verbal IQ and Raven’s Matrices scores. There was little evidence however of any association between motor speed and Performance IQ. These findings are consistent with other research, although the lack of correlation with WAIS-III Performance scores is surprising. [Copyright &y& Elsevier]

There is a persistent belief in clinical psychology and neuropsychology that the Verbal IQ-Performance IQ (VIQ-PIQ) split can be used to reliably infer lateralized brain damage. We selected samples of patients with cleanly lateralized right (n = 23) or left (n = 26) hemisphere lesions and used Bayesian analyses to study the predictive validity of the Wechsler Adult Intelligence Scale-Revised VIQ-PIQ difference scores for identifying lateralized brain damage. The patients showed average VIQ-PIQ differences in the expected direction. However, on the basis of sensitivity, specificity, and positive predictive value statistics, we concluded that (a) the VIQ-PIQ split has no diagnostic predictive validity in persons with left hemisphere lesions (who are not aphasic) and (b) the VIQ-PIQ split has very limited diagnostic predictive validity in persons with right hemisphere lesions. [ABSTRACT FROM AUTHOR]

Several studies of head trauma utilizing the Wechsler Adult Intelligence Scale (WAIS) reported large sample differentials between verbal IQ (VIQ) and performance IQ (PIQ), leading some writers to claim that the VIQ is largely unaffected by traumatic brain injury (TBI), and that a superiority of VIQ over PIQ should be expected. In contrast, our review of Wechsler Adult Intelligence Scale-Revised (WAIS-R) studies indicates that although TBI sample PIQ means are often depressed relative to VIQ means, the differences are small and sometimes in the opposite direction. Possible reasons for the discrepancy between our WAIS-R review and those of an earlier review of WAIS studies are discussed. Clinically, the lack of a VIQ–PIQ difference should never be used to infer that a TBI has not occurred. [ABSTRACT FROM PUBLISHER]

Neural activation patterns, produced while listening to and reading words and non-words, were evaluated by functional MRI in 48 school children, mean age 8 years, in a study at Yale School of Medicine, New Haven, CT.