Structural Validity of the Wechsler Intelligence Scale for Children (WISC-IV) in a French-speaking Swiss sample

The Wechsler Intelligence Scale for Children-fourth edition (i.e. WISC-IV) recognizes a four-factor scoring structure in addition to the Full Scale IQ (FSIQ) score: Verbal Comprehension (VCI), Perceptual Reasoning (PRI), Working Memory (WMI), and Processing Speed (PSI) indices. However, several authors suggested that models based on the Cattell-Horn-Carroll (CHC) theory with 5 or 6 factors provided a better fit to the data than does the current four-factor solution. By comparing the current four-factor structure to CHC-based models, this research aimed to investigate the factorial structure and the constructs underlying the WISC-IV subtest scores with French-speaking Swiss children (N = 249). To deal with this goal, confirmatory factor analyses (CFAs) were conducted. Results showed that a CHC-based model with five factors better fitted the French-Swiss data than did the current WISC-IV scoring structure. All together, these results support the hypothesis of the appropriateness of the CHC model with French-speaking children.

Differential prefrontal-like deficit in children after cerebellar astrocytoma and medulloblastoma tumor

BACKGROUND This study was realized thanks to the collaboration of children and adolescents who had been resected from cerebellar tumors. The medulloblastoma group (CE+, n = 7) in addition to surgery received radiation and chemotherapy. The astrocytoma group (CE, n = 13) did not receive additional treatments. Each clinical group was compared in their executive functioning with a paired control group (n = 12). The performances of the clinical groups with respect to controls were compared considering the tumor's localization (vermis or hemisphere) and the affectation (or not) of the dentate nucleus. Executive variables were correlated with the age at surgery, the time between surgery-evaluation and the resected volume. METHODS The executive functioning was assessed by means of WCST, Complex Rey Figure, Controlled Oral Word Association Test (letter and animal categories), Digits span (WISC-R verbal scale) and Stroop test. These tests are very sensitive to dorsolateral PFC and/or to medial frontal cortex functions. The scores for the non-verbal Raven IQ were also obtained. Direct scores were corrected by age and transformed in standard scores using normative data. The neuropsychological evaluation was made at 3.25 (SD = 2.74) years from surgery in CE group and at 6.47 (SD = 2.77) in CE+ group. RESULTS The Medulloblastoma group showed severe executive deficit (</= 1.5 SD below normal mean) in all assessed tests, the most severe occurring in vermal patients. The Astrocytoma group also showed executive deficits in digits span, semantic fluency (animal category) and moderate to slight deficit in Stroop (word and colour) tests. In the astrocytoma group, the tumor's localization and dentate affectation showed different profile and level of impairment: moderate to slight for vermal and hemispheric patients respectively. The resected volume, age at surgery and the time between surgery-evaluation correlated with some neuropsychological executive variables. CONCLUSION Results suggest a differential prefrontal-like deficit due to cerebellar lesions and/or cerebellar-frontal diaschisis, as indicate the results in astrocytoma group (without treatments), that also can be generated and/or increased by treatments in the medulloblastoma group. The need for differential rehabilitation strategies for specific clinical groups is remarked. The results are also discussed in the context of the Cerebellar Cognitive Affective Syndrome.

Efectos de la deficiencia de yodo sobre variables intelectuales en una población infantil.

An association between severe iodine deficiency and poor mental development has been found in many studies. We examined the relationship between moderate or mild iodine deficiency and intellectual capacity in order to determine whether problems common to severe iodine deficiency (including mental retardation) also emerge in a more subtle form. We also wished to know whether the classic methodology (comparing iodine-deficient zones with nondeficient zones) is the most adequate, and propose to combine this grouping by zones with urinary iodine presented by individuals in each zone. We measured IQ, manipulative and verbal capacity, attention, visual motor ability and disruptive behaviour, variables that have barely been studied in this kind of investigations. The sample comprised 760 schoolchildren from the province of Jaén (southern Spain). Our results show that children with low levels of iodine intake and with urinary iodine concentration lower than 100 microg/litre had a lower IQ and displayed more disruptive behaviour than children with high levels of the criteria. The other variables were not associated with iodine deficiency.

Deficits in executive and memory processes in delusional disorder: a case-control study

OBJECTIVE Delusional disorder has been traditionally considered a psychotic syndrome that does not evolve to cognitive deterioration. However, to date, very little empirical research has been done to explore cognitive executive components and memory processes in Delusional Disorder patients. This study will investigate whether patients with delusional disorder are intact in both executive function components (such as flexibility, impulsivity and updating components) and memory processes (such as immediate, short term and long term recall, learning and recognition). METHODS A large sample of patients with delusional disorder (n = 86) and a group of healthy controls (n = 343) were compared with regard to their performance in a broad battery of neuropsychological tests including Trail Making Test, Wisconsin Card Sorting Test, Colour-Word Stroop Test, and Complutense Verbal Learning Test (TAVEC). RESULTS When compared to controls, cases of delusional disorder showed a significantly poorer performance in most cognitive tests. Thus, we demonstrate deficits in flexibility, impulsivity and updating components of executive functions as well as in memory processes. These findings held significant after taking into account sex, age, educational level and premorbid IQ. CONCLUSIONS Our results do not support the traditional notion of patients with delusional disorder being cognitively intact.

Inferring about individual drug and schizotypy effects on cognitive functioning in polydrug using mephedrone users before and after clubbing

Objective: Mephedrone has been recently made illegal in Europe, but little empirical evidence is available on its impact on human cognitive functions. We investigated acute and chronic effects of mephedrone consumption on drug-sensitive cognitive measures, while also accounting for the influence of associated additional drug use and personality features. Method: Twenty-six volunteers from the general population performed tasks measuring verbal learning, verbal fluency and cognitive flexibility before and after a potential drug-taking situation (pre- and post-clubbing at dance clubs, respectively). Participants also provided information on chronic and recent drug use, schizotypal (O-LIFE) and depressive symptoms (Beck depression inventory), sleep pattern and premorbid IQ. Results: We found that i) mephedrone users performed worse than non-users pre-clubbing, and deteriorated from the pre-clubbing to the post-clubbing assessment, ii) pre-clubbing cannabis and amphetamine (not mephedrone) use predicted relative cognitive attenuations, iii) post-clubbing, depression scores predicted relative cognitive attenuations, and iv) schizotypy was largely unrelated to cognitive functioning, apart from a negative relationship between cognitive disorganisation and verbal fluency. Conclusion: Results suggest that polydrug use and depressive symptoms in the general population negatively affect cognition. For schizotypy, only elevated cognitive disorganisation showed potential links to a pathological cognitive profile previously reported along the psychosis dimension.

Exome sequencing of index patients with retinal dystrophies as a tool for molecular diagnosis.

BACKGROUND: Retinal dystrophies (RD) are a group of hereditary diseases that lead to debilitating visual impairment and are usually transmitted as a Mendelian trait. Pathogenic mutations can occur in any of the 100 or more disease genes identified so far, making molecular diagnosis a rather laborious process. In this work we explored the use of whole exome sequencing (WES) as a tool for identification of RD mutations, with the aim of assessing its applicability in a diagnostic context. METHODOLOGY/PRINCIPAL FINDINGS: We ascertained 12 Spanish families with seemingly recessive RD. All of the index patients underwent mutational pre-screening by chip-based sequence hybridization and resulted to be negative for known RD mutations. With the exception of one pedigree, to simulate a standard diagnostic scenario we processed by WES only the DNA from the index patient of each family, followed by in silico data analysis. We successfully identified causative mutations in patients from 10 different families, which were later verified by Sanger sequencing and co-segregation analyses. Specifically, we detected pathogenic DNA variants (&#8764;50% novel mutations) in the genes RP1, USH2A, CNGB3, NMNAT1, CHM, and ABCA4, responsible for retinitis pigmentosa, Usher syndrome, achromatopsia, Leber congenital amaurosis, choroideremia, or recessive Stargardt/cone-rod dystrophy cases. CONCLUSIONS/SIGNIFICANCE: Despite the absence of genetic information from other family members that could help excluding nonpathogenic DNA variants, we could detect causative mutations in a variety of genes known to represent a wide spectrum of clinical phenotypes in 83% of the patients analyzed. Considering the constant drop in costs for human exome sequencing and the relative simplicity of the analyses made, this technique could represent a valuable tool for molecular diagnostics or genetic research, even in cases for which no genotypes from family members are available.

Drugs, schizotypy and cognition: Cognitive attenuations seem more consistently associated with substance use than schizotypal symptoms

Psychosis is a debilitating disease, causing harm to the individual and society. Since early detection of the disease is associated with a more benign course, factors are warranted that enable the early detection of psychosis. In the present thesis we will be focusing on two potential risk factors, namely schizotypy and drug use. The schizotypy concept, originally developed by Meehl (1962), states that schizophrenia symptoms exist on a spectrum, with symptoms ranging from the most severe in patients with schizophrenia to the least affected individual in the general population. Along the schizophrenia spectrum cognitive impairments are commonly found, for instance reduced hemispheric asymmetry or frontal lobe functions. The second risk factor (drug use), affects similar cognitive functions as those attenuated along the schizophrenia spectrum, and drug use is elevated in schizophrenia and people scoring high on schizotypy. Therefore, we set out to investigate whether cognitive attenuations formerly allocated to schizotypal symptoms could have been influenced by elevated substance use in this population. To test this idea, we assessed various drugs (nicotine, cannabis, mephedrone, general substance dependence) and schizotypy symptoms (O-LIFE), and measured either hemispheric asymmetry of function (left hemisphere dominance for language, and right hemisphere dominance for facial processing) or functions largely relying on the frontal lobes (such as cognitive flexibility, working memory, verbal short-term memory, verbal learning and verbal fluency). Results of all studies suggest that it is mostly drugs, and not schizotypy in general that predict cognitive functioning. Therefore, cognitive attenuations subscribed to schizotypy dimensions are likely to have been affected by enhanced drug use. Future studies should extend the list of potential risk factors (e.g. depression and IQ) to acquire a comprehensive overview of the most reliable predictors of disadvantageous cognitive profiles.

Adaptive strategy for the statistical analysis of connectomes.

We study an adaptive statistical approach to analyze brain networks represented by brain connection matrices of interregional connectivity (connectomes). Our approach is at a middle level between a global analysis and single connections analysis by considering subnetworks of the global brain network. These subnetworks represent either the inter-connectivity between two brain anatomical regions or by the intra-connectivity within the same brain anatomical region. An appropriate summary statistic, that characterizes a meaningful feature of the subnetwork, is evaluated. Based on this summary statistic, a statistical test is performed to derive the corresponding p-value. The reformulation of the problem in this way reduces the number of statistical tests in an orderly fashion based on our understanding of the problem. Considering the global testing problem, the p-values are corrected to control the rate of false discoveries. Finally, the procedure is followed by a local investigation within the significant subnetworks. We contrast this strategy with the one based on the individual measures in terms of power. We show that this strategy has a great potential, in particular in cases where the subnetworks are well defined and the summary statistics are properly chosen. As an application example, we compare structural brain connection matrices of two groups of subjects with a 22q11.2 deletion syndrome, distinguished by their IQ scores.

Sähköpyörätuolin jalkaohjauslaite

Opinnäytetyömme käsitti tuotekehitysprojektin, jossa suunnittelimme, kehitimme ja valmistimme jalkaohjauslaitteen sähköpyörätuoliin. Idea tuotekehitysprojektiin tuli Pasi Mäkirannalta. Tuotekehitysprojektin ideana oli kehittää parempi ja käytännöllisempi jalkaohjauslaite. Jalkaohjauslaitteen pienestä käyttäjäryhmästä johtuen markkinoilla on vain muutama versio jalkaohjauslaitteesta. Jaoimme tuotekehitysprojektin neljään vaiheeseen: käynnistäminen, luonnostelu, kehittäminen ja viimeistely. Tämän selkeytetyn työvaihejaon koimme hyväksi pohjaksi tuotekehitysprojektille. Käynnistämisvaiheessa keräsimme tarvittavaa tietoa jalkaohjauslaittesta ja tutustuimme Pasi Mäkirannan kautta yhteen malliin. Teimme myös kehityskuvauksen, jolla hahmotimme itsellemme tuotekehitysprojektin kokonaisuutta. Luonnosteluvaiheessa mietimme vaihtoehtoisia ratkaisuja ja piirsimme useita luonnoksia. Halusimme painottaa laitteen suorituskykyä, huoltoa, turvallisuutta ja ulkönäköä. Kehittelyvaiheessa aloimme rakentamaan ensimmäistä prototyyppiä. Arvioimme ensimmäisen prototyypin heikkoudet ja ongelmat, joita pyrimme ratkaisemaan toista prototyyppiä rakennettaessa. Viimeistelyvaiheessa hiomme toisen prototyypin yksityiskohtia ja teimme kokoonpanokuvat ja rakennusohjeet. Tuotekehitysprojektissa jalkaohjauslaitetta rakentaessamme otimme huomioon myös seuraavia asioita: laitteen ergonomiset vaatimukset sekä pääkäyttäjäryhmien ALS:n ja CP-oireyhtymän asettamat vaatimukset ohjainlaitteelta. Jalkaohjauslaite on tarkoitettu niille käyttäjille, joille jalkaohjain on soveltuvin ohjainmuoto sähköpyörätuoliin. Vaikka käyttäjäryhmä on pieni, on jalkaohjain käyttäjälleen tärkeä väline, joka mahdollistaa itsenäisen liikumisen ja auttaa selvyitymään arjen toiminnoissa. Koimme vieneemme jalkaohjaimen tuotekehitysprojektia eteenpäin omalta osaltamme.

Poor, Hungry and Stupid: Numeracy and the Impact of High Food Prices in Industrializing Britain, 1780-1850

This paper argues that low levels of nutrition impaired cognitive development in industrializing England, and that welfare transfers mitigated the adverse effects of high food prices. Age heaping is used as an indicator of numeracy, as derived from census data. For the cohorts from 1780-1850, we analyse the effect of high grain prices during the Napoleonic Wars. We show that numeracy declined markedly for those born during the war years, especially when wheat was dear. Crucially, where the Old Poor Law provided for generous relief payments, the adverse impact of high prices for foodstuffs was mitigated. Finally, we show some tentative evidence that Englishmen born in areas with low income support selected into occupations with lower cognitive requirements.

Intra-individual stability of neuromotor tasks from 6 to 18 years: a longitudinal study.

This study investigates the intra-individual stability of the speed of several motor tasks and the intensity of associated movements in 256 children (131 girls, 125 boys) from the Zurich generational study using the Zurich neuromotor assessment battery (ZNA) over a 12-year period from the age of 6 to 18 years. The stability was assessed by correlograms of standard deviation scores calculated from age- and gender-adjusted normative values and compared with standing height and full scale intelligence quotient (IQ). While motor tasks of hand, finger and foot (HFT) and contralateral associated movements (CAM) exhibited a moderate stability (summary measure as correlation coefficients between two measurements made 4 years apart: .61 and .60), other tasks (dynamic balance, static balance and pegboard) were only weakly stable (.46, .47 and .49). IQ and height were more stable than neuromotor components (.72 and .86). We conclude that the moderately stable HFT and CAM may reflect "motor traits", while the stability of the pegboard and balance tasks is weaker because these skills are more experience related and state-dependent.

A adubação nitrogenada e o sintoma de nematóides no algodoeiro

Em dois ensaios de campo de adubação nitrogenada, desenvolvidos com o cultivar IAC 20 de algodão em solos infestados por nematóides, nos municípios de Mococa e Tatuí (SP), em 1988/89, observou-se que a incidência de sintomas na parte aérea das plantas ocorreu de forma diferenciada em função dos tratamentos (0, 25, 50 e 75 kg ha-1 de N-cobertura). Efetuou-se, então, levantamento de sintomas, por parcela experimental, atribuindo às plantas notas crescentes de acordo com a intensidade do ataque: nota 1, para plantas com porte normal e isentas de manchas amareladas e/ou avermelhadas, salpicadas no limbo foliar ("carijó"); 2, com "carijó" (sintoma típico de mosqueamento foliar) nas folhas da base da copa ("baixeiro"); 3, com "carijó" no "baixeiro" e em folhas esparsas; 4, com "carijó" incluindo folhas do ponteiro, e nota 5, para plantas com "carijó" generalizado e deficiente desenvolvimento. A capacidade produtiva do algodoeiro, avaliada nas parcelas sem N, caiu, gradativamente, com a intensidade do "carijó", em especial após nota 3,0, que, em média, representa o deslocamento do sintoma para o ponteiro das plantas. A adubação nitrogenada, por contribuir, significativamente, para diminuir o "carijó" e para aumentar a concentração de N-foliar e a produtividade, pode representar uma alternativa viável no complemento da resistência varietal.

Gesso na produção de cultivares de milho com tolerância diferencial a alumínio em três níveis de calagem

O gesso, nos últimos anos, vem sendo considerado como um insumo capaz de melhorar o ambiente radicular de subsolos ácidos. Contudo, ainda pairam dúvidas sobre a vantagem de usá-lo em solos que, embora ácidos, tenham sido submetidos a calagens e adubações anteriores. Também há pouca informação sobre o uso de gesso em presença de aplicações elevadas de calcário ou em plantas cultivadas tolerantes à acidez. No presente trabalho, é relatado experimento com calcário e gesso, realizado, de 1987 a 1992, na Estação Experimental de Tatuí (SP), em Latossolo Vermelho-Escuro álico textura argilosa, com o objetivo de avaliar o efeito de calcário e de gesso nas produções de cultivares de milho tolerante ou susceptível a alumínio, bem como o efeito dos corretivos na acidez do solo. O experimento foi instalado em parcelas subsubdivididas, com quatro repetições, em blocos ao acaso. Nas parcelas principais, foram aplicadas 0, 6 ou 12 t ha-1 de calcário dolomítico e, nas subparcelas, 0, 4 e 8 t ha-1 de fosfogesso; nas subsubparcelas, foram plantados dois cultivares, um sensível e outro tolerante a alumínio. Para as quatro colheitas obtidas (os dados de 1990 foram considerados perdidos), percebeu-se efeito significativo para a calagem nos dois tipos de cultivares. O gesso apresentou efeito significativo nas produções apenas para o cultivar sensível ao alumínio e, nesse caso, o efeito foi aditivo ao de calcário, proporcionando, em média, cerca da metade do aumento de produção devida à calagem. A calagem influenciou, consideravelmente, a reação da camada arável do solo, aumentando o pH, os teores de Ca2+ e Mg2+ e reduzindo a acidez potencial, mas pouco influiu nas camadas mais profundas, o que, provavelmente, se deveu ao fato de o solo ter recebido aplicações anteriores de calcário e de adubos com sulfato. O gesso influiu nos teores de Ca2+ e SO4(2-) em profundidade, embora de forma pouco pronunciada em relação às quantidades aplicadas, e não alterou as características de acidez. Pode-se concluir que, mesmo tendo alterado pouco as características químicas do subsolo, o gesso favoreceu a produção de cultivar de milho sensível à acidez.

Efeitos da calagem, cobalto e molibdênio sobre a concentração de clorofila nas folhas de amendoim

Para avaliar os efeitos da calagem e da aplicação de cobalto e molibdênio nas sementes sobre a concentração de clorofila em folhas de plantas de amendoim, foram instalados experimentos, no período "das águas", nos anos agrícolas 1990/91 e 1991/92, em área de ocorrência de Latossolo Vermelho-Escuro distrófico textura média. Foram utilizadas quatro doses de calcário dolomítico calcinado: 0, 4, 6 e 8 t ha-1; dois cultivares de amendoim: "Tatu" e "Tupã", e quatro tratamentos de sementes: não tratadas, tratadas com cobalto, com molibdênio e com cobalto mais molibdênio. Verificou-se que, em condições de elevada acidez do solo, a aplicação de molibdênio nas sementes aumentou a concentração de clorofila nas folhas do amendoim, com efeito semelhante ao da calagem na ausência de molibdênio. A concentração de clorofila correlacionou-se positivamente com o teor de nitrogênio nas folhas, indicando que os efeitos da calagem e da aplicação de molibdênio sobre a concentração de clorofila foram basicamente ocasionados pela melhoria do processo de fixação simbiótica do nitrogênio por maior atividade da nitrogenase. Houve aumento linear da produção de vagens e grãos do cultivar "Tatu" com o aumento da concentração de clorofila nas folhas e, no caso do cultivar "Tupã", a máxima produção de vagens e grãos foi obtida para concentração de clorofila nas folhas de 4,6 mg dm-2.