Investigations into the relationship of the PPVT-R and the WISC-R with incarcerated delinquents

Examined the relationship between the Peabody Picture Vocabulary Test-Revised (PPVT-R), the Peabody Picture Vocabulary Test (PPVT), and the Wechsler Intelligence Scale for Children-Revised (WISC-R) with 35 incarcerated delinquents between the ages of 13–10 and 16–10. Mean scaled scores were computed across all measures. A statistically significant difference (p <. 01) between the PPVT-R mean scaled score and all other measures was obtained. The PPVT-R correlated significantly (p <. 0001) with the WISC-R VIQ (r = 0.87), PIQ (r = 0.78), FSIQ (r = 0.86) and the PPVT (r = 0.80), whereas the original PPVT demonstrated significant yet lower correlations with the WISC-R VIQ (r = 0.78), PIQ (r = 0.77) and FSIQ (r = 0.80). The clinical significance of utilizing the PPVT-R as a measure of receptive vocabulary and its practical relationship to the PPVT and WISC-R with a juvenile delinquent population was discussed.     

The Genetic Basis of Academic Achievement on the Queensland Core Skills Test and its Shared Genetic Variance with IQ

First, this study examined genetic and environmental sources of variation in performance on a standardised test of academic achievement, the Queensland Core Skills Test (QCST) (Queensland Studies Authority, 2003a). Second, it assessed the genetic correlation among the QCST score and Verbal and Performance IQ measures using the Multidimensional Aptitude Battery (MAB), [Jackson, D. N. (1984) Multidimensional Aptitude Battery manual. Port Huron, MI:Research Psychologist Press, Inc.]. Participants were 256 monozygotic twin pairs and 326 dizygotic twin pairs aged from 15 to 18 years (mean 17 years ± 0.4 [SD]) when achievement tested, and from 15 to 22 years (mean 16 years ± 0.4 [SD]) when IQ tested. Univariate analysis indicated a heritability for the QCST of 0.72. Adjustment to this estimate due to truncate selection (downward adjustment) and positive phenotypic assortative mating (upward adjustment) suggested a heritability of 0.76 The phenotypic (0.81) and genetic (0.91) correlations between the QCST and Verbal IQ (VIQ) were significantly stronger than the phenotypic (0.57) and genetic (0.64) correlations between the QCST and Performance IQ (PIQ). The findings suggest that individual variation in QCST performance is largely due to genetic factors and that common environmental effects may be substantially accounted for by phenotypic assortative mating. Covariance between academic achievement on the QCST and psychometric IQ (particularly VIQ) is to a large extent due to common genetic influences.     

Brain syndrome and WAIS PIO VIO difference scores corrected for test artifact

Found an artifactual discrepancy of six units between VIQ and PIQ in Ss (N = 62) of low and bright, but not of mid-range IQ. Despite the matching of psychiatric cases for dominant and nondominant cognitive function, the discrepancy took the form of a lowered PIQ. The application of an equivalent correction to the PIQs of consecutive and unmatched psychiatric cases failed to improve the neurological predictive utility of the VIQ PIQ difference score. The latter failed statistically as an alerting device for abnormal CT and EEG results and whether a neurological event was recorded in the file. Despite the observation of a strong relationship between CT outcome and VIQ PIQ difference score evidence of cognitive intactness, it was concluded that difference score, whether corrected or not, should be used with extreme caution as a screening device for psychiatric cases who might be harboring an underlying brain syndrome.     

Food Neophobia in Young Adults: Genetic Architecture and Relation to Personality,Pleasantness and Use Frequency of Foods,and Body Mass Index—A Twin Study

Food neophobia has been studied extensively in children, but its causal origins and relationship to eating behavior in adults are not well understood. We studied genetic and environmental effects on variation in food neophobia, measured using the Food Neophobia Scale, and explored associations between food neophobia and personality, pleasantness and use frequency of food groups, and body mass index in young adult twins (N = 1175, aged 20–25 years, 54.7% women). In women, additive genetic effects (heritability) accounted for 61% of variation in food neophobia, whereas in men, shared environmental effects explained 45% of the variation. Food neophobia negatively correlated with the personality trait Openness, corrected for the structural overlap (r = −0.23), and in women, these two traits had a genetic correlation (r _g = −0.39). In addition, food neophobia negatively correlated with pleasantness and use frequency of fruits and vegetables and of fish and with mean pleasantness of foods. Once evolutionarily important, food neophobia should at present be considered in nutrition counseling as a possible barrier to a balanced diet.     

无症状性脑梗死患者认知功能障碍与抑郁和梗死部位的关系

目的 :探讨无症状性脑梗死 (ACI)患者的认知功能障碍与抑郁和梗死部位、数量的关系。方法 :选择 5 6例ACI患者作为研究对象 ,用修订韦氏成人智力量表和记忆量表、汉密顿抑郁量表等方法检测。结果 :1.双侧梗死组VIQ、FIQ及MQ显著低于右侧梗死组 (P <0 .0 5～ 0 .1) ,左侧梗死组VIQ、FIQ显著低于右侧梗死组 ;2 .皮质合并皮质下梗死组、皮质梗死组MQ显著低于皮质下梗死组 (P <0 .0 1) ;3.多灶梗死组VIQ、PIQ、FIQ及MQ分均显著低于单灶梗死组 (P <0 .0 5～ 0 .0 1) ;4 .抑郁组各智商及MQ显著低于正常组 (P <0 .0 1) ,非抑郁组VIQ显著低于正常组 (P<0 .0 5 )。抑郁组MQ显著低于非抑郁组 (P <0 .0 1) ,抑郁组和非抑郁组各智商比较未见显著差异。结论 :双侧梗死、皮质合并皮质下梗死、多发性梗死及抑郁的患者更易产生认知功能障碍。     

A model for simulation and patient-specific visualization of the tissue volume of influence during brain microdialysis

Microdialysis can be used in parallel to deep brain stimulation (DBS) to relate biochemical changes to the clinical outcome. The aim of the study was to use the finite element method to predict the tissue volume of influence (TVI_max) and its cross-sectional radius (r _TVImax) when using brain microdialysis, and visualize the TVI_max in relation to patient anatomy. An equation based on Fick’s law was used to simulate the TVI_max. Factorial design and regression analysis were used to investigate the impact of the diffusion coefficient, tortuosity and loss rate on the r _TVImax. A calf brain tissue experiment was performed to further evaluate these parameters. The model was implemented with pre-(MRI) and post-(CT) operative patient images for simulation of the TVI_max for four patients undergoing microdialysis in parallel to DBS. Using physiologically relevant parameter values, the r _TVImax for analytes with a diffusion coefficient D = 7.5 × 10⁻⁶ cm²/s was estimated to 0.85 ± 0.25 mm. The simulations showed agreement with experimental data. Due to an implanted gold thread, the catheter positions were visible in the post-operative images. The TVI_max was visualized for each catheter. The biochemical changes could thereby be related to their anatomical origin, facilitating interpretation of results.     

Depressive Symptoms and Alcohol Use are Genetically and Environmentally Correlated Across Adolescence

Depressive symptoms and alcohol use are frequently positively associated during adolescence. This study aimed to assess the heritability of each phenotype across adolescence; to assess potential shared liabilities; to examine changes in the nature of shared liabilities across adolescence; and to investigate potential causal relationships between depressive symptoms and alcohol use. We studied a longitudinally assessed sample of adolescent Finnish twins (N = 1,282) to test hypotheses about genetic and environmental influences on these phenotypes within and across ages, using data from assessments at ages 12, 14, and 17.5 years. The heritability of depressive symptoms is consistent across adolescence (~40–50%), with contributions from common and unique environmental factors. The heritability of alcohol use varies across time (a² = .25–.44), and age 14 alcohol use is heavily influenced by shared environmental factors. Genetic attenuation and innovation were observed across waves. Modest to moderate genetic (r_A = .26–.59) and environmental (r_C = .30–.63) correlations between phenotypes exist at all ages, but decrease over time. Tests for causal relationships between traits differed across ages and sexes. Intrapair MZ difference tests provided evidence for reciprocal causation in girls at ages 14 and 17.5. Formal causal models suggested significant causal relationships between the variables in both boys and girls. The association between depressive symptoms and alcohol use during adolescence is likely due to a combination of shared genetic and environmental influences and causal influences. These influences are also temporally dynamic, complicating efforts to understand factors contributing to the relationship between these outcomes.     

Genetic and Environmental Influences on Risky Sexual Behaviour and its Relationship With Personality

Risky sexual behaviour is a major health issue in society, and it is therefore important to understand factors that may predispose individuals to such behaviour. Research suggests a link between risky sexual behaviour and personality, but the basis of this link remains unknown. Hans Eysenck proposed that personality is related to sexual behaviour via biological underpinnings of both. Here we test the viability of this perspective by analysing data from identical and non-identical twins (N = 4,904) who completed a questionnaire assessing sexual attitudes and behaviour as well as personality. Using genetic modelling of the twin data, we found that risky sexual behaviour was significantly positively correlated with Impulsivity (r = .27), Extraversion (r = .24), Psychoticism (r = .20), and Neuroticism (r = .09), and that in each case the correlation was due primarily to overlapping genetic influences. These findings suggest that the genetic influences that shape our personality may also predispose us to risky sexual behaviour.     

Cognitive profiles of children with early onset of unilateral lesions

The level and pattern of Wechsler Intelligence Scale for Children‐Revised (WISC‐R) performance for 18 left‐lesioned (LL) and 13 right‐lesioned (RL) children with clearly defined unilateral involvement and no ongoing seizure disorders were compared to normal controls matched by age, sex, race, and social class. Verbal IQ (VIQ), Performance IQ (PIQ), and Full Scale IQ (FIQ) were well within normal limits for all groups, although RL children scored significantly lower than right controls. No significant differences between VIQ, PIQ, and FIQ were found within the LL or RL or control groups; thus VIQ and PIQ discrepancy was not found to relate to lesion laterally. When WISC‐R subtests were recategorized according to Kaufman's factors, the Freedom from Distractibility factor was impaired in both LL and RL children, whereas RL children were also deficient on the Perceptual Organization factor. Level and pattern of cognitive performance are discussed in relation to age of lesion onset and site of lesion within a hemisphere.     

Differential Genetic Etiology of Reading Difficulties as a Function of IQ: An Update

In order to test the hypothesis that the genetic etiology of reading disability differs as a function of IQ, composite reading performance data from 308 pairs of identical (monozygotic, MZ) twins and 440 pairs of fraternal (dizygotic, DZ) twins (254 same-sex and 186 opposite-sex) in which at least one member of each pair was classified as reading-disabled were subjected to multiple regression analysis (DeFries and Fulker, Behav Genet 15:467–473, 1985; Acta Genet Med Gemellol 37:205–216, 1988). In the total sample, heritability of the group deficit in reading performance (h_g²) was .61 (±.06). However, results of fitting an extended regression model to reading performance and IQ data suggested that the genetic etiology of reading disability differs as a linear function of IQ (p ≤ .04). When the basic regression model was fitted separately to data from twin pairs with Wechsler (Examiner's manual: Wechsler intelligence scale for children—revised, 1974; Examiner's manual: Wechsler adult intelligence scale—revised, 1981) Full Scale IQ scores in the upper and lower 25% of the sample, resulting estimates of h_g² were .75 (±.12) and .50 (±.10), respectively (p ≤ .045). These results suggest that reading difficulties in children with a higher IQ are due substantially to genetic influences and may require intensive remediation efforts.     

Systematic VIQ/PIQ differences on the WAIS: An artifact of this instrument?

Investigated the possibility that there exists a systematic VIQ/PIQ discrepancy on the WAIS that did not exist on the WBI or WBII. Five hundred and ten psychiatric patients who were referred for psychological testing were assigned randomly to one of three groups: Ss in Group 1 were administered the WAIS as a part of the test battery, Ss in Group 2 were administered the WBI and Ss in Group 3 were administered the WBII. Results indicated that the IQ scores provided by the WAIS were significantly (p < 0.01) lower than those provided by the other instruments and that a systematic VIQ/PIQ discrepancy in favor of the VIQ exists on this test, which was not found on the other instruments. Implications of these findings were discussed in regard to both clinical use of the WAIS and continuing research on its diagnostic utility.     

A Twin Study of the Genetics of High Cognitive Ability Selected from 11,000 Twin Pairs in Six Studies from Four Countries

Although much genetic research has addressed normal variation in intelligence, little is known about the etiology of high cognitive abilities. Using data from 11,000 twin pairs (age range = 6–71 years) from the genetics of high cognitive abilities consortium, we investigated the genetic and environmental etiologies of high general cognitive ability (g). Age-appropriate psychometric cognitive tests were administered to the twins and used to create g scores standardized within each study. Liability-threshold model fitting was used to estimate genetic and environmental parameters for the top 15% of the distribution of g. Genetic influence for high g was substantial (0.50, with a 95% confidence interval of 0.41–0.60). Shared environmental influences were moderate (0.28, 0.19–0.37). We conclude that genetic variation contributes substantially to high g in Australia, the Netherlands, the United Kingdom and the United States. Edited by Dick Rose.     

Comparison of various WISC-R summary scores for a psychiatric sample

Compared two sets of summary scores for the Wechsler Intelligence Scale for Children-Revised (WISC-R). The traditional scores used to summarize information about WISC-R performance (i.e., Verbal IQ (VIQ), Performance IQ (PIQ) and discrepancy between VIQ and PIQ) were compared to scores based on the three factors identified by Kaufman (1975) (i.e., Verbal Comprehension (VC), Perceptual Organization (PO) and Freedom from Distractibility (FD). Ss were 260 psychiatric outpatients who were administered the WISC-R during a 4-year period. The independent variables were sex and DSM II diagnosis. There were significant main effects for diagnosis for the VC and FD scales. There was a significant interaction for VIQ and nonsignificant results for the VIQ-PIQ discrepancy score. The groups did not differ in perceptual organization skills as assessed by PO and PIQ. Delinquents performed particularly poorly on the VC scale; hyperactive children had the highest VC score and relatively low scores on the FD factor; learning disabled children had low VC and FD scores. These findings suggest that the scores based on Kaufman's factors provided important clinical summary information that was not available from the traditional scores.     

Perceptual speed does not cause intelligence, and intelligence does not cause perceptual speed

There is ongoing debate whether the efficiency of local cognitive processes leads to global cognitive ability or whether global ability feeds the efficiency of basic processes. A prominent example is the well-replicated association between inspection time (IT), a measure of perceptual discrimination speed, and intelligence (IQ), where it is not known whether increased speed is a cause or consequence of high IQ. We investigated the direction of causation between IT and IQ in 2012 genetically related subjects from Australia and The Netherlands. Models in which the reliable variance of each observed variable was specified as a latent trait showed IT correlations of -0.44 and -0.33 with respective Performance and Verbal IQ; heritabilities were 57% (IT), 83% (PIQ) and 77% (VIQ). Directional causation models provided poor fits to the data, with covariation best explained by pleiotropic genes (influencing variation in both IT and IQ). This finding of a common genetic factor provides a better target for identifying genes involved in cognition than genes which are unique to specific traits.     

Description and Validation of a Dynamical Systems Model of Presynaptic Serotonin Function: Genetic Variation,Brain Activation and Impulsivity

Despite more than a decade of empirical work on the role of genetic polymorphisms in the serotonin system on behavior, the details across levels of analysis are not well understood. We describe a mathematical model of the genetic control of presynaptic serotonergic function that is based on control theory, implemented using systems of differential equations, and focused on better characterizing pathways from genes to behavior. We present the results of model validation tests that include the comparison of simulation outcomes with empirical data on genetic effects on brain response to affective stimuli and on impulsivity. Patterns of simulated neural firing were consistent with recent findings of additive effects of serotonin transporter and tryptophan hydroxylase-2 polymorphisms on brain activation. In addition, simulated levels of cerebral spinal fluid 5-hydroxyindoleacetic acid (CSF 5-HIAA) were negatively correlated with Barratt Impulsiveness Scale (Version 11) Total scores in college students (r = −.22, p = .002, N = 187), which is consistent with the well-established negative correlation between CSF 5-HIAA and impulsivity. The results of the validation tests suggest that the model captures important aspects of the genetic control of presynaptic serotonergic function and behavior via brain activation. The proposed model can be: (1) extended to include other system components, neurotransmitter systems, behaviors and environmental influences; (2) used to generate testable hypotheses.     

Schizotypy,neuroticism, and saccadic eye movements: New data and meta‐analysis

Deficits on saccade tasks, particularly antisaccade performance, have been reliably reported in schizophrenia. However, less evidence is available on saccade performance in relation to schizotypy, a personality constellation harboring risk for schizophrenia. Here, we report a large empirical study of the associations of schizotypy and neuroticism with antisaccade and prosaccade performance (Study I). Additionally, we carried out meta‐analyses of the association between schizotypy and antisaccade error rate (Study II). In Study I, N = 526 healthy individuals from the general population aged 18–54 years completed prosaccade and antisaccade tasks as well as the Schizotypal Personality Questionnaire (SPQ). Schizotypy was significantly associated with increased antisaccade error rate, with the disorganized dimension emerging as strongest predictor (β = .118, p = .007). Neuroticism emerged as a significant predictor for prosaccade gain (β = .103, p = .023) and antisaccade latency (β = .101, p = .025). In Study II, random‐effects meta‐analyses were performed on the published data and those from Study I. Meta‐analyses revealed significant associations (all p ≤ .003) of antisaccade error rate with positive (g = 0.37), negative (g = 0.26), disorganized (g = 0.36) and overall schizotypy (g = 0.37). Overall, the present work replicates the association between antisaccade direction errors and schizotypy. Significant findings from meta‐analyses provide further evidence of the antisaccade error rate as a putative schizophrenia spectrum marker.     

Brain white matter damage in aging and cognitive ability in youth and older age

Cerebral white matter hyperintensities (WMH) reflect accumulating white matter damage with aging and impair cognition. The role of childhood intelligence is rarely considered in associations between cognitive impairment and WMH. We studied community-dwelling older people all born in 1936, in whom IQ had been assessed at age 11 years. We assessed medical histories, current cognitive ability and quantified WMH on MR imaging. Among 634 participants, mean age 72.7 (SD 0.7), age 11 IQ was the strongest predictor of late life cognitive ability. After accounting for age 11 IQ, greater WMH load was significantly associated with lower late life general cognitive ability (β = ?0.14, p < 0.01) and processing speed (β = ?0.19, p < 0.001). WMH were also associated independently with lower age 11 IQ (β = ?0.08, p < 0.05) and hypertension. In conclusion, having more WMH is significantly associated with lower cognitive ability, after accounting for prior ability, age 11IQ. Early-life IQ also influenced WMH in later life. Determining how lower IQ in youth leads to increasing brain damage with aging is important for future successful cognitive aging.     

Superior Temporal Gyrus,Language Function,and Autism

Deficits in language are a core feature of autism. The superior temporal gyrus (STG) is involved in auditory processing, including language, but also has been implicated as a critical structure in social cognition. It was hypothesized that subjects with autism would display different size-function relationships between the STG and intellectual-language-based abilities when compared to controls. Intellectual ability was assessed by either the Wechsler Intelligence Scale for Children–Third Edition (WISC–III) or Wechsler Adult Intelligence Scale–Third Edition (WAIS–III), where three intellectual quotients (IQ) were computed: verbal (VIQ), performance (PIQ), and full-scale (FSIQ). Language ability was assessed by the Clinical Evaluation of Language Fundamentals–Third Edition (CELF–3), also divided into three index scores: receptive, expressive, and total. Seven to 19-year-old rigorously diagnosed subjects with autism (n = 30) were compared to controls (n = 39; 13 of whom had a deficit in reading) of similar age who were matched on education, PIQ, and head circumference. STG volumes were computed based on 1.5 Tesla magnetic resonance imaging (MRI). IQ and CELF–3 performance were highly interrelated regardless of whether subjects had autism or were controls. Both IQ and CELF–3 ability were positively correlated with STG in controls, but a different pattern was observed in subjects with autism. In controls, left STG gray matter was significantly (r = .42, p ≤ .05) related to receptive language on the CELF–3; in contrast, a zero order correlation was found with autism. When plotted by age, potential differences in growth trajectories related to language development associated with STG were observed between controls and those subjects with autism. Taken together, these findings suggest a possible failure in left hemisphere lateralization of language function involving the STG in autism. Superior Temporal Gyrus, Language Function, and Autism     

Effect of maternal HIV infection,BMI and NOx air pollution exposure on birth outcomes in South African pregnant women genotyped for the p53 Pro72Arg (rs1042522)

Tumour suppressor protein, p53, plays a role in modulating innate immune responses, DNA repair, cell cycle arrest, senescence and apoptosis. Maternal nitrogen oxide (NOx) air pollution exposure, body mass index (BMI), human immunodeficiency virus (HIV) infection and p53 Pro72Arg (rs1042522) affect foetal growth. We investigated whether the aforementioned factors influence birth outcomes in a South African population. Pregnant women (n = 300; HIV ?ve = 194 and HIV +ve = 106) were genotyped for the p53 rs1042522 using polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP), and further stratified based on HIV status, infants' birthweight (BW; NBW: normal BW [>2,500 g] and LBW: low BW [<2,500 g]) and gestational age (GA; NGA: normal GA [>37 weeks] and PTB: preterm birth [≤37 weeks]). A land use regression model was developed to characterize maternal NOx exposure. Pearson's correlation and multivariate regression analysis statistical tests were used to determine the effect of rs1042522 genotyped pregnant women's BMI and NOx exposure on maternal blood pressure and haemoglobin and iron levels, and infants' anthropometric measurements and Appearance Pulse Grimace Activity and Respiration (APGAR) scores. The prevalence of LBW and PTB was 14.7% and 18.7%, respectively. The LBW group had a higher frequency of the variant Arg‐allele versus NBW group (47.7% vs. 31.4%, p = .0046, OR = 2.0, 95% CI = 1.26–3.17). No association was observed between NGA and PTB groups. A significant association between BMI and systolic blood pressure (r = .50, p = .00; B = 0.76, p = .002) and birth length (r = ?.28, p = .01; B = ?0.107, p = .011), and NOx and birth length (r = ?.26, p = .08; B = ?0.191, p = .046) and birthweight (B = ?8.87, p = .048) was observed in HIV‐infected mothers with the variant Pro/Arg + Arg/Arg genotypes. Mothers from the LBW group with the variant genotypes displayed an association between NOx and diastolic blood pressure (r = .58, p = .04), blood iron levels (r = ?.60, p = .04; B = ?0.204, p = .004), APGAR scores at 1 min (r = ?.86, p = .00; B = ?0.101, p = .003) and 5 min (r = ?.75, p = .01) and birth length (r = ?.61, p = .04), and BMI and diastolic blood pressure (r = .72, p = .01). In the PTB group, maternal variant genotypes and NOx were associated with blood haemoglobin levels (B = ?0.132, p = .045) and APGAR scores at 1 min (B = ?0.161, p = .045) and 5 min (B = ?0.147, p = .043). Maternal rs1042522 Arg‐allele, HIV infection, BMI and NOx exposure collectively play a role in lowering blood iron levels, gestational hypertension and LBW outcomes.