Epilepsy in Children With Congenital Heart Disease: Risk Factors and Characteristic Presentations.

BACKGROUND: Children with a congenital heart disease (CHD) are at a higher risk of developing epilepsy than the general population, but detailed characteristics of CHD-associated epilepsy have not been clarified. The purposes of this study were to determine the risk factors for developing epilepsy associated with CHD and to elucidate the characteristics of such epilepsy. METHODS: We performed a retrospective cohort study based on medical records of pediatric patients with CHD who were born between January 2006 and December 2016, underwent cardiac surgery at Okayama University Hospital, and were followed up until at least age three years. Multivariate logistic regression analysis was used to determine factors particularly associated with epilepsy occurrence. In patients who developed epilepsy, clinical data on seizure characteristics were further investigated. RESULTS: We collected data from 1024 patients, and 41 (4.0%) developed epilepsy. The presence of underlying disease (odds ratio [OR]: 2.413; 95% confidence interval [CI]: 1.150 to 4.883) and the Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery score category 2 (OR: 4.373; 95% CI: 1.090 to 29.150) and category 5 (OR: 10.385; 95% CI: 1.717 to 89.016) were significantly related to epilepsy occurrence. Of the 41 patients with epilepsy, 15 (including nine with hypoplastic left heart syndrome) had focal impaired awareness seizures specified as autonomic seizures with vomiting, which tends to escape detection. CONCLUSIONS: We clarified the risk factors for developing epilepsy in children with CHD. We also found that autonomic seizure with vomiting is an important symptom in these children.

A study on the relationship between non-epileptic fast (40 - 200 Hz) oscillations in scalp EEG and development in children.

OBJECTIVE: Physiological gamma and ripple activities may be linked to neurocognitive functions. This study investigated the relationship between development and non-epileptic, probably physiological, fast (40-200 Hz) oscillations (FOs) including gamma (40 - 80 Hz) and ripple (80 - 200 Hz) oscillations in scalp EEG in children with neurodevelopmental disorders. METHODS: Participants were 124 children with autism spectrum disorder (ASD) and/or attention deficit/hyperactivity disorder (ADHD). Gamma and ripple oscillations were explored from 60-second-long sleep EEG data in each subject using a semi-automatic detection tool supplemented with visual confirmation and time-frequency analysis. RESULTS: Gamma and ripple oscillations were detected in 25 (20.2%) and 22 (17.7%) children, respectively. The observation of one or more occurrence(s) of ripple oscillations, but not gamma oscillations, was significantly related to lower age at EEG recording (odds ratio, OR: 0.727 [95% confidence interval, CI: 0.568-0.929]), higher intelligence/developmental quotient (OR: 1.041, 95% CI: 1.002-1.082), and lack of a diagnosis with ADHD (OR: 0.191, 95% CI: 0.039 - 0.937) according to a binominal logistic regression analysis that included diagnosis with ASD, sex, history of perinatal complications, history of febrile seizures, and use of a sedative agent for the EEG recording as the other non-significant parameters. Diagnostic group was not related to frequency or power of spectral peaks of FOs. CONCLUSION: The production of non-epileptic scalp ripples was confirmed to be associated with brain development and function/dysfunction in childhood. Further investigation is necessary to interpret all of the information on higher brain functions that may be embedded in scalp FOs.

Predicting the reading skill of Japanese children.

OBJECTIVE: To clarify cognitive processes underlining the development of reading in children speaking Japanese as their first language, we examined relationships between performances of cognitive tasks in the preschool period and later reading abilities. METHODS: Ninety-one normally developing preschoolers (41 girls and 50 boys; 5years 4months to 6years 4months, mean 5years 10months) participated as subjects. We conducted seven cognitive tasks including phonological awareness tasks, naming tasks, and working memory tasks in the preschool period. In terms of reading tasks, the hiragana naming task was administered in the preschool period; the reading times, which is a composite score of the monomoraic syllable reading task, the word and the non-word reading tasks, and the single sentence reading task, was evaluated in first and second grade; and the kanji reading task (naming task) was tested in second grade. Raven's colored progressive matrices and picture vocabulary test revised were also conducted in first grade. Correlation analyses between task scores and stepwise multiple regression analyses were implemented. RESULTS: Tasks tapping phonological awareness, lexical access, and verbal working memory showed significant correlations with reading tasks. In the multiple regression analyses the performances in the verbal working memory task played a key role in predicting character naming task scores (the hiragana naming task and the kanji reading task) while the digit naming task was an important predictor of reading times. Unexpectedly, the role of phonological (mora) awareness was modest among children speaking Japanese. CONCLUSION: Cognitive functions including phonological awareness, digit naming, and verbal working memory (especially the latter two) were involved in the development of reading skills of children speaking Japanese.

Inhibitory function and working memory in attention deficit/hyperactivity disorder and pervasive developmental disorders: does a continuous cognitive gradient explain ADHD and PDD traits?

To clarify the relationship between attention deficit/hyperactivity disorder (AD/HD) and pervasive developmental disorders (PDD), we investigated the common features and differences of these disorders in neuropsychological profiles. The subjects were 4 groups of Japanese boys aged 6 to 15 years, categorized by diagnosis:AD/HD (n＝20), PDD with comorbid AD/HD (PDD＋:n＝16), PDD without comorbid AD/HD (PDD－:n＝8), and typically developing (n＝60). We evaluated executive function (EF) through verbal and visuospatial memory tasks, the Go/NoGo task, and the color-word matching Stroop task. We performed a categorical analysis to estimate the effects of the 3 disorders on EF and a dimensional analysis to estimate the effects of symptom scales on EF. We found that the AD/HD and PDD＋ subjects had negative effects on verbal working memory and intra-individual response variability. The severity of these impairments was positively correlated with the inattentiveness score. The subjects with a PDD＋ or PDD－ diagnosis had poorer scores on interference control;the severity of this impairment was correlated with the PDD symptom score. Impairments in visuospatial working memory were detected in the AD/HD and PDD－ groups but not in the PDD＋ group. Impairments in inhibition of the pre-potent response were noted in all 3 categories. AD/HD and PDD share neuropsychological features, though each disorder has a specific impairment pattern. Our findings partially support the idea that AD/HD and PDD are on a spectrum.

Questionnaire-based assessment of behavioral problems in Japanese children with epilepsy.

Behavioral problems in Japanese children with epilepsy were investigated by means of a questionnaire for parents consisting of three checklists: the Child Behavior Checklist (CBCL)/4-18 Japanese Edition, the High-Functioning Autism Spectrum Screening Questionnaire (ASSQ), and the Attention-Deficit/Hyperactivity Disorder (ADHD) Rating Scale-IV (ADHD-RS) for parents. The participants were the parents of 108 children aged 6-18 years with apparently normal intelligence. The CBCL indicated abnormal behavior in 10.5 to 35.6% of the children, and T scores on both the internalizing and externalizing scales had a significant positive relation with scores on the ASSQ and ADHD-RS. It was revealed through multivariate logistic regression analysis that the persistence of seizures was significantly related with abnormality on the externalizing scale of the CBCL (p=0.010, odds ratio: 3.48, 95% confidence interval: 1.34-9.02). Future studies are needed to determine whether seizure freedom improves behavior in children with epilepsy.

Relationships between the color-word matching Stroop task and the Go/NoGo task: toward multifaceted assessment of attention and inhibition abilities of children.

Both selective attention and response inhibition can be assessed through the Stroop task and the Go/NoGo task (Go/NoGo). The color-word matching Stroop task (cwmStroop) differs from the traditional Stroop task in ways that make it easy to administer, and it enables the examiners to analyze reaction time. It is expected that the cwmStroop and Go/NoGo tasks will be useful as clinical assessments for children with developmental disorders and in combination with functional magnetic resonance imaging studies. The objectives of this study were to elucidate the pattern of developmental change in cwmStroop scores and Go/NoGo scores and to determine whether and how cwmStroop scores are related to Go/NoGo scores. The subjects consisted of 108 healthy Japanese children aged 6-14 years. We found that cwmStroop and Go/NoGo scores displayed clear developmental changes between 6 and 14 years of age. The children's scores on the 2 tasks followed different developmental courses, however, and the correlation between scores on the two tasks was weak on the whole. These results indicate that the cwmStroop and Go/NoGo tasks tap different aspects of selective attention and response inhibition. Therefore it is expected that the combination of both tests will be useful in the multifaceted assessment of selective attention and response inhibition in childhood.

[A study of reading disorder comorbid with pervasive developmental disorder or attention-deficit/hyperactivity disorder].

OBJECTIVE: We investigated the frequency and characteristics of reading disorder comorbid with pervasive developmental disorder (PDD) or attention-deficit/hyperactivity disorder (AD/HD). METHODS: Articulation times and reading errors were evaluated using four Japanese reading tasks (a monomoraic syllable reading task, a word reading task, a non-word reading task, and a short sentence reading task) in 31 children with PDD (22 boys and 9 girls) aged 6-14 years (average 9.5 years) and 39 children with AD/HD (33 boys and 6 girls) aged 6-12 years (average 9.6 years). Poor readers (PRs) were identified when articulation times were significantly longer than those of typically-developing children (> or = 2.0 SD) for two or more reading tasks, and non-PRs were identified when articulation times were within normal range (<2.0 SD) for all reading tasks. RESULTS: Eight children with PDD (25.8%) and 17 children with AD/HD (43.6%) were identified as PRs. For 13 of the 70 subjects, the chief complaints were difficulties in reading and writing words at their first visit to our hospital. All 13 of these subjects had AD/HD, and twelve of these were additionally identified as PRs. Among the remaining 26 children with AD/HD, five (19.2%) were identified as PRs. In AD/HD children, PRs made significantly more reading errors and had lower IQ scores than did non-PRs, but in PDDchildren, there were no significant differences between these two groups regarding IQ or reading errors. An analysis using the Clinical-Symptoms-Checklist for Reading and Writing Words revealed that PRs in our study showed difficulties in reading words in daily life. CONCLUSIONS: PRs in our study had reading disorders, which would, in turn, mean that reading disorder was often comorbid with PDD or AD/HD. These results strongly indicate the necessity of testing for the presence of reading disorder in children with PDD or AD/HD.

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.

Reading skills of Japanese second-graders.

BACKGROUND: A few studies have explored the prevalence of dyslexia among children who speak Japanese as their native language by evaluating them individually by means of reading-based tasks. The present study was designed to clarify the frequency of suspected dyslexia among second-graders attending ordinary classes. METHODS: The subjects were 40 children (22 males, 18 females; 7 years 4 months-8 years 4 months; mean age, 7 years 11 months) out of 182 second-graders at a public elementary school situated in a local city. Each subject underwent a monomoraic syllable reading task, a word reading task, a non-word reading task, and a short sentence reading task. RESULTS: The scores on the four tests were not normally distributed; rather, they were strongly skewed to shorter reading time or fewer reading errors. In addition, they were significantly extended toward either longer reading time or more reading errors. Except in the non-word reading task, most subjects only made a few reading errors. Seven subjects (17.5%) showed at least one score that was more than 1.5 IQR (interquartile range) higher than the third quartile of that subject's eight scores on the four tasks. Assuming that those seven children are potentially dyslexic, at least 3.8% of second-graders (seven out of 182) are suspected to be suffering from dyslexia. CONCLUSION: It is likely that the prevalence of dyslexia in Japan is comparable to that in Europe and the US. To confirm this, a more comprehensive study on a larger scale should be implemented in the future.

[Developmental changes in visuospatial working memory].

We investigated the developmental changes in visuospatial working memory using the Visuospatial Span Task (VST) and the Matrix Visuospatial Working Memory Test (VSWMT). VST is a short-term storage task, while VSWMT is a complex dual task. VSWMT requires the use of storage, processing, and selective attention, all of which are thought to be supported by the central executive (Baddeley). The subjects of this study were 60 typically developing children (43 boys and 17 girls) aged 6-14 years (average 10.4 years). For each task we evaluated span scores and the number of total passed trials, and investigated the changes that occurred with age. To further elucidate age-related changes in visuospatial working memory, we divided the subjects into three age groups (Group A: 6-8 years, Group B: 9-11 years, and Group C: 12-14 years of age), and statistically evaluated the differences between the groups. In both tasks, span scores and the number of total passed trials showed definite age-related changes from 6 to 14 years of age. Span scores and the number of total passed trials in VSMWT continued to increase until adolescence, with significant differences between the three age groups, while those in VST increased significantly between Groups A and B (the number of total passed trials only) and between Groups A and C (span scores and the number of total passed trials); there was no significant difference between Groups B and C, however. These results suggest that the network of the brain involved in visuospatial working memory gradually matures during early school years and adolescence, and that the basic mechanisms of this network exist by 6-7 years of age. Our results also show that VST and VSWMT are suitable tests for the evaluation of visuospatial working memory in childhood and adolescence.

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.