Neander Abreu

Elevated airborne manganese and low executive function in school-aged children in Brazil

Exposure to airborne manganese (Mn) has been associated with neurotoxic effects, including motor and cognitive deficits. The main deficits related to excessive exposure to Mn are predominantly the dysfunction of fronto-striatal and dopaminergic circuits observed in animal experimental studies, which are involved in attention, working memory and motor function. The present study aims to assess the association between elevated Mn exposure and performance on executive function and attention neuropsychological tests in children living in two communities near a ferro-manganese alloy plant. Seventy children aged between 7 and 12 years with no history of neurologic disease and an estimated IQ >68 (Vocabulary and Block Design subtests) that had lived near the iron-Mn production alloy plant for at least 1.5 years were included. Participants were assessed for cognitive functioning with neuropsychological measures for sustained attention (Test of Visual Attention - TAVIS-3R), cognitive flexibility (WCST), and verbal and visual working memory (WISC-III Digit Span subtest and Corsi Block). Manganese hair (MnH) levels were used as a biomarker of exposure. Mean scores among study participants were lower than general population norms/averages for block design, digit span, reaction time and commission errors. The median MnH level was 11.48 (range 0.52-55.74) μg/g, and no difference between sexes was observed. Spearmans correlation analysis showed a significant inverse correlation between MnH levels and estimated IQ (rho=-0.448, p=0.0001), Vocabulary (rho=-0.272, p=0.02), Block Design (rho=-0.485, p=0.00002) and Digit Span (rho=-0.410, p=0.0004). Multiple regression analyses detected inverse associations between log MnH and scores on estimated IQ (β=-9.67; 95%CI=-16.97 to -2.37), Block Design (β=-2.50; 95%CI=-3.91 to -1.10) and Digit Span Total (β=-2.59; 95%CI=-4.13 to -1.05) standardized scores and the number of correct answers in forward and backward Digit Span methods, after adjusting for covariates (β=-1.32=95%CI=-2.23 to -0.40; β=-1.09 95%CI=-2.02 to -0.16, respectively). The results suggest that airborne Mn exposure may be associated with lower IQ and neuropsychological performance in tests of executive function of inhibition responses, strategic visual formation and verbal working memory. Executive function is dependent on the fronto-striatal circuit, which may be disrupted by Mn accumulation in the brain.

Tradução e adaptação cultural da Barratt Impulsiveness Scale (BIS-11) para aplicação em adultos brasileiros

OBJECTIVES: The objective of this study was to translate, make transcultural adaptation and assess the semantic, idiomatic and literal equivalence of the Barratt Impulsiveness Scale (BIS-11). METHODS:This scale assesses the presence of impulsive manifestations from the theoretical model proposed by Ernst Barratt. Firstly, the BIS-11 original version in English was translated to Portuguese by six bilingual researches. After this, was made the back-translation to English by a translator that was born in United States. Then, the three versions (original, translated and back-translated) were assessed by a specialists committee which made and analyze and comments about the process and then we reach the final translated version of BIS-11. The original and translated version of BIS-11 was applied in two samples from general population with proficiency both in English and Portuguese. This method was adopted to assess the literal, semantic e idiomatic equivalence of these versions by mean of correlation analyses. CONCLUSION: The final results of quantitative analyses show that the final version of BIS-11 is satisfactory.

Versão abreviada do WISC-III: correlação entre QI estimado e QI total em crianças brasileiras

In order to calculate the correlation between the Estimated IQ and the Full Scale IQ of children submitted to the WISC III, four different data banks with a total of 207 children were integrated: (1) typically developing children, (2) children diagnosed as having Attention Deficit/ Hyperactivity Disorder, (3) children identified by private clinics as having learning disabilities (4) children with neurological sequelae diagnosed by a public university outpatient treatment program. Results suggest that the Estimated IQ, which is based on the weighted sum of the subtest scores of Cubes and Vocabulary, may be used in the presence of time constraints, when intellectual performance is important for screening in research procedures, and as a reference within a broader neuropsychological evaluation.

Noninvasive biomarkers of manganese exposure and neuropsychological effects in environmentally exposed adults in Brazil

Manganese (Mn), an essential element to humans, in excess can cause neurotoxic damage. So far, Mn exposure assessment has no ideal biomarker. This study aims to investigate the association between Mn exposure, using noninvasive biomarkers, and neuropsychological effects in environmentally exposed adults. The residents of two communities near to a ferromanganese refinery in Bahia, Brazil were evaluated. Volunteers aged 15-55 of both sexes provided scalp hair, axillary hair, fingernail and saliva specimens for Mn determination by electrothermal absorption spectrometry. Several neuropsychological tests were used to evaluate cognitive, attention, memory, motor and executive functions. Significant correlations were observed between Mn in hair (MnH, median 8.95 μg/g), axillary hair (MnAxH,18.49 μg/g) and fingernail (MnFN, 6.91 μg/g) with the performances in several neuropsychological tests. No association was observed between manganese levels in saliva (MnSal, 4.2 μg/L) and any neuropsychological function. Multiple regression analysis detected an inverse association between Log MnH and IQ (β=-4.76 [CI 95% -9.17 to -0.36]) and between Log MnFN and visual working memory (β=-3.33 [CI 95% -6.15 to -0.52]). Direct association was observed between Log MnFN and time of completion in the cognitive flexibility task (β=56.29 [CI 95% 2.41-110.18]). The Mn biomonitoring using noninvasive biomarkers was able to detect high exposure levels, which were associated with detrimental neuropsychological effects in adults exposed to industrial emissions.

Executive functioning and reading achievement in school: a study of Brazilian children assessed by their teachers as “poor readers”

This study examined executive functioning and reading achievement in 106 6- to 8-year-old Brazilian children from a range of social backgrounds of whom approximately half lived below the poverty line. A particular focus was to explore the executive function profile of children whose classroom reading performance was judged below standard by their teachers and who were matched to controls on chronological age, sex, school type (private or public), domicile (Salvador/BA or São Paulo/SP) and socioeconomic status. Children completed a battery of 12 executive function tasks that were conceptual tapping cognitive flexibility, working memory, inhibition and selective attention. Each executive function domain was assessed by several tasks. Principal component analysis extracted four factors that were labeled “Working Memory/Cognitive Flexibility,” “Interference Suppression,” “Selective Attention,” and “Response Inhibition.” Individual differences in executive functioning components made differential contributions to early reading achievement. The Working Memory/Cognitive Flexibility factor emerged as the best predictor of reading. Group comparisons on computed factor scores showed that struggling readers displayed limitations in Working Memory/Cognitive Flexibility, but not in other executive function components, compared to more skilled readers. These results validate the account that working memory capacity provides a crucial building block for the development of early literacy skills and extends it to a population of early readers of Portuguese from Brazil. The study suggests that deficits in working memory/cognitive flexibility might represent one contributing factor to reading difficulties in early readers. This might have important implications for how educators might intervene with children at risk of academic under achievement.

A neuropsychological study comparing patients infected with HCV and HBV without psychiatric comorbidities.

Hepatitis C is one of the most common chronic infectious diseases worldwide, with well‐documented extra‐hepatic manifestations, such as a broad number of cognitive deficits. These impairments may be explained by psychiatric comorbidities, which have not been investigated properly in the literature. In order to elucidate a specific hepatitis C virus (HCV) induced cognitive impairment not related to mental disorders, neuropsychological performance of patients infected with HCV was compared with that of patients infected with hepatitis B virus cognitive impairment, especially psychiatric comorbidities. A total of 33 patients infected with HCV and 22 patients infected with HBV were included in the study. There were no significant differences between the two groups with regard to age or years of education. The group of patients infected with HCV performed significantly worse on visuo‐spatial memory tasks after adjusting for years of education and age. There were no significant differences between patients infected with HCV and patients infected with HBV with regards to other neuropsychological functions. The data indicate that patients infected with HCV patients have poorer visuo‐spacial memory performance than patients infected with HBV, suggesting that the cognitive deficit may be specific to HCV infection and not to secondary comorbid psychiatric disorders. J. Med. Virol. 81:1184–1188, 2009.

Normative data of the Barratt Impulsiveness Scale 11 (BIS-11) for Brazilian adults

OBJECTIVE The Barratt Impulsiveness Scale (BIS-11) is a valid and reliable instrument, and one of the most often used tools to assess impulsivity. This study assesses the performance of a large sample of adults by using a version of BIS-11 adapted to Brazilian Portuguese. METHODS We assessed 3,053 adults from eight Brazilian states. Internal consistencies and performance data were presented for two correction criteria of BIS-11: original and the two-factor score. RESULTS The associations between age, sex, region, and education and the BIS-11 scores present very small effect sizes. Therefore, we provided a percentile rank parameter for the different BIS-11 subscores considering the whole sample. Given the internal consistency of the two correction systems, we found that only the two-factor system fulfills the psychometric criteria of Cronbachs alpha (cutoff value of at least 0.6). CONCLUSION Our results support the use of the Brazilian adaptation of BIS-11 in different regions of the country as a measure of impulsivity. Since high impulsiveness is a characteristic of several dysfunctional behaviors, the establishment of normative parameters is of utmost relevance and should be extended to other age ranges and populations in future studies.

Working memory screening, school context, and socioeconomic status: An analysis of the effectiveness of the Working Memory Rating Scale in Brazil

Objective: The study explores the psychometric properties of the Brazilian-Portuguese version of the Working Memory Rating Scale (WMRS-Br) in a population of 355 young children from diverse socioeconomic status and schooling backgrounds. Method: Public and private school teachers completed the WMRS-Br and children were assessed on a range of objective cognitive measures of fluid intelligence, working memory, and attention. Results: Reliability and validity of the WMRS-Br were excellent across the public and private school sample. The WMRS-Br manifested substantial links with objective measures of working memory and medium links with selective attention, switching, and interference suppression. Confirmatory factor analyses suggest that a shorter version of the scale provides an adequate fit to the data. Conclusion: The WMRS-Br represents a valid screening tool in a Latin American context that has the potential to improve the early detection of working memory deficits in children growing up in poverty.

Emotion Regulation Checklist (ERC): estudos preliminares da adaptação e validação para a cultura brasileira

The Emotion Regulation Checklist (ERC) is an instrument for the hetero-evaluation of the level of emotion regulation of children by means of two scales, Emotion Regulation (ER) and Emotional Lability/ 1 Endereço para correspondência: Universidade Federal de Mato Grosso do Sul, Centro de Ciências Humanas e Sociais, Departamento de Ciências Humanas. Cidade Universitária s/n, Campus Universitário, 79070-900, Campo Grande, MS, Brasil, Caixa-postal: 549, Telefone: (67) 3345-7577. E-mail: alinehreis@gmail.com, sergioeduardos.oliveira@gmail.com, deniserbandeira@gmail.com, nara.c.andrade@gmail.com, neandersa@ hotmail.com e sperbt@gmail.com Reis, A. H., Oliveira, S. E. S., Bandeira, D. R., Andrade, N. C., Abreu, N., Sperb, T. M. 78 Negativity (L/N). ER assesses the expression of emotions, empathy, and emotional self-awareness, while L/N assesses the lack of fl exibility, anger dysregulation, and mood lability. The aim of this study is to perform the translation and cross-cultural adaptation of the ERC and investigate evidence of the validity of its Brazilian version. Two studies are conducted: Study I – Translation and cross-cultural adaptation of ERC for use in Brazil; and Study II – Investigation of evidence of the validity of the ERC. The sample includes 561 informants (parents and teachers) on children aged 3-12 years old. The exploratory factor analysis (EFA) assumptions are adequate, and the two-factor solution (ER and L/N) is shown to be the most adequate, explaining 57% of the variance (L/N α = .77 and ER α = .73). Subscale L/N is positively correlated with measurements of behavioral problems, while subscale ER is positively correlated with measurements of social skills. The present study provides the fi rst evidence of the validity of the ERC for use in the Brazilian context.

Performance comparison between right-handers and left-handers in a brazilian sample of the developmental neuropsychological assessment

Studies that investigate handedness are performed in order to relate hemispheric specialization and cognitive performance. The aim of study was compare the neuropsychological performance between right-handed and left-handed children with ages from five to six years who participated in the Brazilian study of standardization of the Developmental Neuropsychological Assessment. For analysis of socio-demographic characteristics, descriptive statistics were used. To compare the mean scores between the groups, normality was tested using Analysis of Variance (one-way Anova) and the Kruskal-Wallis test. When comparing right-handed and left-handed children with typical development, left-handed children presented poorer performance on the subtests involving Attention and Executive Functioning, Language, and Learning and Memory.