Yoko Kado

The Rey-Osterrieth Complex Figure as a Measure of Executive Function in Childhood

In adults, the Rey-Osterrieth Complex Figure (ROCF) can be used for the assessment of not only visuoconstructional ability and visual memory, but also executive function in adults. We studied whether ROCF scores also correlated with executive function in childhood. The subjects consisted of 56 patients with various neurological diseases (5 years 7 months-14 years 11 months; mean: 8 years 8 months; M 42, F 14) whose full-scale IQs were 70 or higher (mean: 93.3). All subjects underwent the Wechsler Intelligence Scale for children third edition (WISC-III) and various psychological tests focusing on executive function. We evaluated the ROCF with the Boston Qualitative Scoring System (BQSS). We calculated the partial correlation coefficients between the BQSS Summary Scores and representative scores of other executive function tests, using age as the control variable. Among the scores of the various examinations, the Perseverative Errors of Nelson of the Wisconsin Card Sorting Test, the raw scores of the Mazes (WISC-III), the Digit Span (WISC-III), and the Block Design (WISC-III) were correlated significantly with two to four BQSS Summary Scores (P<0.05 or P<0.01). In contrast, the scores of the Trail Making Test, the Stroop Test, and the Commission Error of Continuous Performance Test-II did not show a significant correlation with any of the BQSS Summary Scores. The ROCF evaluated with the BQSS reflects not only visuoperceptual ability and visuoconstructional ability, but also executive function, especially planning and organization. However, a new BQSS Summary Score should be devised since no existing BQSS index specifically reflects executive functions with an outstandingly strong correlation.

Japanese version of the Frontal Assessment Battery for dementia

The Frontal Assessment Battery (FAB) was developed as a short bedside cognitive and behavioral battery to assess frontal lobe functions. The purpose of this study was to evaluate the validity and reliability of a Japanese version of the FAB to measure cognitive dysfunction in patients with dementia. We studied 25 normal subjects and 105 patients with Alzheimers disease, n=58, vascular dementia, n=24, and frontotemporal dementia, n=23. The neuropsychological test battery included the FAB, the Mini Mental State Examination (MMSE), a memory test, and the Wisconsin Card Sorting Test (Keio version: KWCST). Patients with dementia performed significantly more poorly than controls on all tests. The FAB showed a good correlation with other cognitive measures: MMSE (r=0.725), KWCST number of categories completed (r=0.654), KWCST number of perseveration errors (r=-0.484), and memory test (r=0.643). Patients with more severe Clinical Dementia Rating scores showed lower scores on the FAB. There was good inter-rater reliability (r=0.972), test-retest reliability (r=0.769), and internal consistency (Cronbachs coefficient alpha=0.715). The FAB is a valid and reliable screening test to evaluate cognitive dysfunction among patients with dementia.

Prenatal exposure to traffic-related air pollution and child behavioral development milestone delays in Japan

Background: Recent studies suggest that prenatal exposure to outdoor air pollution is associated with unfavorable neurodevelopment in children. We examined associations between prenatal exposure to traffic-related air pollution and child behavioral development milestone delays, using data from a nationwide population-based longitudinal survey in Japan, where the participants were recruited in 2001 and followed. Methods: Particulate matter, nitrogen dioxide, and sulfur dioxide concentrations during the 9 months before birth were obtained at the municipality level and assigned to the participants who were born in the corresponding municipality. We analyzed data from singleton births with linked pollution data available (N = 33,911 at the maximum). We used responses to survey questions about age-appropriate behaviors at ages 2.5 and 5.5 years as indicators of behavioral development. We conducted multilevel logistic regression analysis, adjusting for individual and municipality-level variables. Results: Air pollution exposure during gestation was positively associated with the risk of some developmental milestone delays at both ages. Specifically, air pollution was associated with verbal and fine motor development at age 2.5 years, and with behaviors related to inhibition and impulsivity at 5.5 years. In the fully-adjusted models, odds ratios following one-interquartile-range increase in nitrogen dioxide and suspended particulate matter were 1.24 (95% confidence interval: 1.07, 1.43) for inability to compose a two-phrase sentence at ages 2.5 and 1.10 (1.05, 1.16) for inability to express emotions at age 5.5 years, respectively. Conclusions: Prenatal exposure to traffic-related air pollution was associated with behavioral development milestone delays of children in a nationally representative sample in Japan.

Predicting executive function task scores with the Rey-Osterrieth Complex Figure.

The Boston Qualitative Scoring System (BQSS) is one of the scoring methods of the Rey-Osterrieth Complex Figure Test (ROCF). With BQSS, 17 qualitative ratings are generated, and subsequently 6 summary scores are calculated by combining several qualitative scores. Previously we showed that 5 of 6 BQSS summary scores were correlated with the scores of the several executive function tests in children. The objective of this study was to develop a new summary score which correlates with the executive function test scores more strongly than the existing summary scores. For this purpose, we conducted multiple regression analysis to predict PEN, CA, DSM of the Wisconsin Card Sorting Test Keio Version, and the Mazes scores from WISC-III, by the BQSS qualitative scores derived from ROCF drawings in copy condition. The subjects were 78 children with various neuropsychological disorders (5 years 5 months-14 years 11 months; mean: 9 years 2 months; F 22, M 56). Significant predictive models were generated for PEN, CA, and Mazes scores. Among them the models for the Mazes scores were the most accurate. The second model for the Mazes scores was most suitable for a new summary score. Its degree-of-freedom-adjusted coefficient of multiple determination and multiple correlation coefficient reached 0.467 and 0.695, respectively. A new summary score should be applied in future studies to evaluate its clinical usefulness.

Executive function in children with pervasive developmental disorder and attention-deficit/hyperactivity disorder assessed by the Keio version of the Wisconsin card sorting test

The Wisconsin card sorting test (WCST) comprehensively examines executive function (EF). The Keio version of the WCST (KWCST) uses fewer cards and presents them in two steps, separated by a short pause during which an instruction is given. Being of short duration, this test is suitable for children with pervasive developmental disorder (PDD) and attention-deficit/hyperactivity disorder (AD/HD), yet few studies have examined the performance of children with such developmental disorders in the second step of a two-step test such as the KWCST. Using the KWCST, this study compares EF in children with PDD (n=52), or AD/HD (n=46) to that in typically developing (TD) children (n=52). Scores for the six indices of this test, including numbers of response cards until the first category achieved (NUCA), total errors (TE), and non-perseverative errors of Nelson (NPEN), were analyzed using ANOVA. Compared to the TD group, scores in the PDD and/or AD/HD groups were significantly lower for all indices except NUCA and NPEN for the first step, and lower for all indices except NUCA for the second step. Moreover, significantly fewer improvements in TE were seen in the PDD group, and significantly fewer improvements in NPEN were seen in the AD/HD group, compared with TD. This study suggests that both PDD and AD/HD make it difficult for children to utilize their experience in the first step and to effectively apply the instruction given before the second step. It also suggests that the two-step nature of the KWCST is clinically important.

Intrauterine Exposure to Methylmercury and Neurocognitive Functions: Minamata Disease.

A large-scale food poisoning caused by methylmercury was identified in Minamata, Japan, in the 1950s. The severe intrauterine exposure cases are well known, although the possible impact of low-to-moderate methylmercury exposure in utero are rarely investigated. We examined neurocognitive functions among 22 participants in Minamata, mainly using an intelligence quotient test (Wechsler Adults Intelligent Scale III), in 2012/2013. The participants tended to score low on the Index score of processing speed (PS) relative to full-scale IQ, and discrepancies between PS and other scores within each participant were observed. The lower score on PS was due to deficits in digit symbol-coding and symbol search and was associated with methylmercury concentration in umbilical cords. The residents who experienced low-to-moderate methylmercury exposure including prenatal one in Minamata manifested deficits in their cognitive functions, processing speed in particular.

Prenatal exposure to outdoor air pollution and child behavioral problems at school age in Japan

INTRODUCTION Recent studies suggest positive associations between prenatal exposure to ambient air pollution and neurodevelopment of children, but evidence on the adverse effects of exposure to air pollution on child neurobehavioral development remains limited. We thus examined associations between prenatal exposure to outdoor air pollution and child behavioral problems at school age, using data from a nationwide population-based longitudinal survey in Japan, where participants were recruited in 2001 and are continuously followed. METHODS Suspended particulate matter (SPM), nitrogen dioxide, and sulfur dioxide concentrations during the 9months before birth were obtained at municipality level and assigned to those participants born in the corresponding municipality. We analyzed data from singleton births with linked pollution data available (e.g., n=33,911 for SPM). We used responses to survey questions about behavioral problems at age 8years. We conducted multilevel logistic regression analysis, adjusting for individual and municipality-level variables. RESULTS Air pollution exposure during gestation was positively associated with risk for behavioral problems related to attention and delinquent or aggressive behavior. In the fully adjusted models, odds ratios following a one-interquartile-range increase in SPM were 1.06 (95% confidence interval: 1.01, 1.11) for interrupting others, 1.09 (1.03, 1.15) for failure to pay attention when crossing a street, 1.06 (1.01, 1.11) for lying, and 1.07 (1.02, 1.13) for causing public disturbance. CONCLUSIONS Prenatal exposure to outdoor air pollution was associated with behavioral problems related to attention and delinquent or aggressive behavior at age 8years in a nationally representative sample in Japan.

Preterm birth and behavioural outcomes at 8 years of age: a nationwide survey in Japan

Objective To analyse the effect of different preterm birth categories on behavioural outcomes. Design Prospective cohort design. Settings The Japanese Longitudinal Survey of Babies in the 21st Century was used for the study. Subjects Neonates born in 2001 in Japan (n=34 163) and followed up at the age of 8 years. Post-term births were excluded and the sample was divided into four groups according to gestational age: <34 weeks, 34–36 weeks, 37–38 weeks and 39–41 weeks. Outcome measures Seven behavioural outcomes were examined: three attention problems and four delinquent/aggressive behaviours. Results Logistic regression was used to estimate adjusted ORs and 95% CIs for each outcome. Positive associations were found between preterm birth (<37 weeks) and adverse behavioural outcomes compared with full-term birth (39–41 weeks). For attention problems, the OR for ‘inability to wait his/her turn’ was increased by 1.72 (95% CI 1.22 to 2.43) for gestational age <34 weeks and by 1.28 (95% CI 1.03 to 1.59) for 34–36 weeks’ gestation. For delinquent/aggressive behaviour, the OR for the outcome ‘destroying books/toys’ was increased by 1.46 (95% CI 1.07 to 1.99) for gestational age <34 weeks, while the outcome ‘disturbance in public’ was increased by 1.20 (95% CI 1.04 to 1.38) for 34–36 weeks’ gestation. Conclusions Children who are born <34 weeks, but also between 34 and 36 weeks, are at increased risk of behavioural problems related to attention and delinquent/aggressive behaviour when 8 years old.

Neurological and neurocognitive functions from intrauterine methylmercury exposure

ABSTRACT In the 1950s, large-scale food poisoning caused by methylmercury was identified in Minamata, Japan. Although severe intrauterine exposure cases (ie, congenital Minamata disease patients) are well known, possible impacts of methylmercury exposure in utero among residents, which is likely at lower levels than in congenital Minamata disease patients, are rarely explored. In 2014, the authors examined neurological and neurocognitive functions among 18 exposed participants in Minamata, focusing on fine motor, visuospatial construction, and executive functions. More than half of the participants had some fine motor and coordination difficulties. In addition, several participants had lower performance for neurocognitive function tests (the Rey-Osterrieth Complex Figure test and Keio version of the Wisconsin card sorting test). These deficits imply diffuse brain damage. This study suggests possible neurological and neurocognitive impacts of prenatal exposure to methylmercury among exposed residents of Minamata.