A longitudinal study of overweight during childhood : etiology, mental health outcomes and mediating factors

Au cours des 30 dernières années, l’embonpoint et l’obésité infantile sont devenus de véritables défis pour la santé publique. Bien que l’obésité soit, à la base, un problème physiologique (i.e. balance calorique positive) une série de facteurs psychosociaux sont reliés à son développement. Dans cette thèse, nous avons étudié le rôle des facteurs périnataux et de la petite enfance dans le développement du surpoids, ainsi que la relation entre le surpoids et les troubles internalisés au cours de l’enfance et au début de l’adolescence. Nous avions trois objectifs généraux: 1) Modéliser le développement de l’indice de masse corporelle (IMC) ou du statut pondéral (le fait d’être en surpoids ou non) durant l’enfance, ainsi qu’estimer l’hétérogénéité dans la population au cours du temps (i.e. identification de trajectoires développementales de l’IMC). 2) Identifier les facteurs périnataux et de la petite enfance pouvant accroitre le risque qu’un enfant suive une trajectoire menant au surpoids adolescente. 3) Tester la possibilité que le surpoids durant l’enfance soit associé avec des problèmes de santé mentale internalisés à l’adolescence, et vérifier la possibilité qu’une telle association soit médiatisée par l’expérience de victimisation par les pairs et l’insatisfaction corporelle. Ce travail est mené dans une perspective de développement au cours de la vie (life span perspective), considérant l’accumulation des facteurs de risques au cours du temps ainsi que les facteurs qui se manifestent durant certaines périodes critiques de développement.1,2 Nous avons utilisé les données provenant de l’Étude Longitudinale du Développement des Enfants du Québec (ELDEQ), une cohorte de naissances de la province de Québec, Canada. L’échantillon initial était composé de 2120 familles avec un bébé de 5 mois nés au Québec en 1997. Ces familles ont été suivies annuellement ou à tous les deux ans jusqu’à ce que les enfants atteignent l’âge de 13 ans. En ce qui concerne le premier objectif de recherche, nous avons utilisé la méthode des trajectoires développementales fondée sur des groupes pour modéliser l’IMC en continu et en catégories (surpoids vs poids normal). Pour notre deuxième objectif, nous avons effectué des modèles de régression multinomiale afin d’identifier les facteurs périnataux et de la petite enfance associés aux différents groupes développementaux du statut pondéral. Les facteurs de risques putatifs ont été choisis parmi les facteurs identifiés dans la littérature et représentent l’environnement périnatal, les caractéristiques de l’enfant, ainsi que l’environnement familial. Ces facteurs ont été analysés longitudinalement dans la mesure du possible, et les facteurs pouvant servir de levier potentiel d’intervention, tels que l’usage de tabac chez la mère durant la grossesse, le sommeil de l’enfant ou le temps d’écoute de télévision, ont été sélectionnés pour l’analyse. Pour notre troisième objectif, nous avons examiné les associations longitudinales (de 6 à 12 ans) entre les scores-z d’IMC (selon la référence CDC 2000) et les problèmes internalisés avec les modèles d’équations structurales de type « cross-lagged ». Nous avons ensuite examiné comment la victimisation par les pairs et l’insatisfaction corporelle durant l’enfance peuvent médiatiser un lien potentiel entre le surpoids et les troubles internalisés au début de l’adolescence. Les contributions scientifiques de la présente thèse incluent l’identification de trajectoires distinctes du statut pondérale durant l’enfance (précoce, tardive, jamais en surpoids), ainsi que les facteurs de risques précoces et les profils de santé mentale pouvant différer selon la trajectoire d’un enfant. De plus, nous avons identifié des mécanismes importants qui expliquent une partie de l’association entre les trajectoires de surpoids et les troubles internalisés: la victimisation par les pairs et l’insatisfaction corporelle.

Reintegro y permanencia universitaria en Bogotá : el caso de la Facultad de Ingeniería de la Universidad Distrital, 2000-2009

El presente trabajo de investigación, estudia a través del caso de la cohorte del 2000 de la Facultad de Ingeniería de la Universidad Distrital, el tipo de coyuntura que le permitió a este grupo de jóvenes reingresar a la Universidad y culminar la carrera al haber tenido que abandonarla en un primer momento, por problemas socio-económicos y/o académicos. Por medio del estudio del reintegro universitario, este trabajo se enmarca en el campo, poco explorado, de la existencia y efectividad de medidas de "segundas oportunidades" educativas que las instituciones de educación superior le ofrecen a estudiantes que por problemas de orden estructural se ven obligados a abandonar la Universidad.

La efectividad de diferentes métodos de la enseñanza de la lecto-escritura en español. Una revisión de literatura

Para la enseñanza de lecto-escritura de español en niños existen diferentes métodos usados por los profesores. La importancia de los métodos de lecto-escritura usados para los niños de la primera infancia se vincula con el futuro educativo y profesional de la persona. Por tanto, la preocupación de este trabajo es hacer una revisión de literatura sobre cuáles son los métodos usados por las diferentes instituciones y evaluar la efectividad de dichos métodos en la enseñanza de lecto-escritura. Se hace la revisión de 26 artículos, de los cuales 15 son estudios hechos por diferentes autores para evaluar la efectividad de los diferentes métodos. En el contexto de los artículos revisados se encuentra el método global, el sintético, el fonético, el silábico, el ecléctico, junto con estrategias pictofónicas y el programa de Experiencias Comunicativas en Situaciones variadas de lectura y escritura (ECOS). Los hallazgos permiten concluir que sí hay métodos más efectivos que otros en la enseñanza de lecto-escritura de español en niños. También se puede concluir de acuerdo a la revisión, que la familiaridad de las palabras y el entrenamiento en habilidades fonológicas juega un papel importante en el desempeño de los niños en la realización de las diferentes tareas.

Pre-school contributions to future achievements

This paper provides recent evidence about the beneÖts of attending preschool on future performance. A non-parametric matching procedure is used over two outcomes: math and verbal scores at a national mandatory test (Saber11) in Colombia. It is found that students who had the chance of attending preschool obtain higher scores in math (6.7%) and verbal (5.4%) than those who did not. A considerable fraction of these gaps comes from the upper quintiles of studentís performance, suggesting that preschool matters when is done at high quality institutions. When we include the number of years at the preschool, the gap rises up to 12% in verbal and 17% in math.

Atypical neural self-representation in autism

The 'self' is a complex multidimensional construct deeply embedded and in many ways defined by our relations with the social world. Individuals with autism are impaired in both self-referential and other-referential social cognitive processing. Atypical neural representation of the self may be a key to understanding the nature of such impairments. Using functional magnetic resonance imaging we scanned adult males with an autism spectrum condition and age and IQ-matched neurotypical males while they made reflective mentalizing or physical judgements about themselves or the British Queen. Neurotypical individuals preferentially recruit the middle cingulate cortex and ventromedial prefrontal cortex in response to self compared with other-referential processing. In autism, ventromedial prefrontal cortex responded equally to self and other, while middle cingulate cortex responded more to other-mentalizing than self-mentalizing. These atypical responses occur only in areas where self-information is preferentially processed and does not affect areas that preferentially respond to other-referential information. In autism, atypical neural self-representation was also apparent via reduced functional connectivity between ventromedial prefrontal cortex and areas associated with lower level embodied representations, such as ventral premotor and somatosensory cortex. Furthermore, the magnitude of neural self-other distinction in ventromedial prefrontal cortex was strongly related to the magnitude of early childhood social impairments in autism. Individuals whose ventromedial prefrontal cortex made the largest distinction between mentalizing about self and other were least socially impaired in early childhood, while those whose ventromedial prefrontal cortex made little to no distinction between mentalizing about self and other were the most socially impaired in early childhood. These observations reveal that the atypical organization of neural circuitry preferentially coding for self-information is a key mechanism at the heart of both self-referential and social impairments in autism.

The development of children of postnatally depressed mothers: evidence from the Cambridge longitudinal study

Children with a parent who suffers from depression are at raised risk for the disorder themselves. Relatively little is known about the development of psychological vulnerability to depression through childhood, particularly during infancy and early childhood. This paper describes results from a longitudinal prospective study of the development of children, studied from birth to 16 years, of mothers who experienced postnatal depression; it highlights the roles of the developing mother-child relationship, and of physiological functioning and social relationships in the development of adolescent vulnerability.

Thinking for speaking and linguistic relativity among bilinguals: towards a new research agenda

This article evaluates how the different papers in this special issue fill a gap in our understanding of cognitive processes that are being activated when second language learners or bilinguals prepare to speak. All papers are framed in Slobin’s (1987) Thinking for Speaking theory, and aim to test whether the conceptualisation patterns that were learned in early childhood can be relearned or restructured in L2 acquisition. In many papers the focus is on identifying constraints on this restructuring process. Among these constraints, the role of typological differences between languages is investigated in great depth. The studies involve different types of learners, language combinations and tasks. As all informants were given verbal rather than non-verbal tasks, the focus is here on the effects of conceptual transfer from one language on another, and not on the effects of language on non-linguistic cognition. The paper also sketches different avenues for further research in this field and proposes that researchers working in this field might want to take up the challenge of investigating whether speakers of different languages perceive motion outside explicitly verbal contexts differently, as this will enable us to gain an understanding of linguistic relativity effects in this domain. Studying which teaching methods can help learners to restructure their conceptualisation patterns may also shed new light on the aspects of discourse organization and motion event construal that are most difficult for learners.

Implicit learning and imperceptible influence: Syncretic literacy of multilingual Chinese children.

This article reports on an ethnographic study involving the literacy practices of two multilingual Chinese children from two similar yet different cultural and linguistic contexts: Montreal and Singapore. Using syncretism as a theoretical tool, this inquiry examines how family environment and support facilitate children’s process of becoming literate in multiple languages. Informed by sociocultural theory, the inquiry looks in particular at the role of grandparents in the syncretic literacy practices of children. Through comparative analysis, the study reveals similarities and differences that, when considered together, contribute to our understanding of multilingual children’s creative forms of learning with regard to their rich literacy resources in multiple languages, the imperceptible influences of mediators, various learning styles and syncretic literacy practices.

The role of temperament and family environment in the development of anxiety disorder: two-year follow-up

Objective Behavioural inhibition (BI) in early childhood is associated with increased risk for anxiety. The present research examines BI alongside family environment factors, specifically maternal negativity and overinvolvement, maternal anxiety and mother-child attachment, with a view to providing a broader understanding of the development of child anxiety. Method Participants were 202 children classified at age 4 as either behaviourally inhibited (N=102) or uninhibited (N=100). Family environment, BI and child anxiety were assessed at baseline and child anxiety and BI were assessed again two-years later when participants were aged 6 years. Results After controlling for baseline anxiety, inhibited participants were significantly more likely to meet criteria for a diagnosis of social phobia and generalized anxiety disorder at follow-up. Path analysis suggested that maternal anxiety significantly affected child anxiety over time, even after controlling for the effects of BI and baseline anxiety. No significant paths from parenting or attachment to child anxiety were found. Maternal overinvolvement was significantly associated with BI at follow-up. Conclusions At age 4, BI, maternal anxiety and child anxiety represent risk factors for anxiety at age 6. Furthermore, overinvolved parenting increases risk for BI at age 6, which may then lead to the development of anxiety in later childhood.

Promoting mother–infant book sharing and infant attention and language development in an impoverished South African population: a pilot study

The low rates of child literacy in South Africa are cause for considerable concern. Research from the developed world shows that parental sharing of picture books with infants and young children is beneficial for child language and cognitive development, as well as literacy skills. We conducted a pilot study to examine whether such benefits might extend to an impoverished community in South Africa, by evaluating the impact of training mothers in book sharing with their 14–18 month old infants. Seventeen mothers received book sharing training; and 13 mothers did not, but instead received a comparison training in toy play. We assessed the mothers’ behavior during both book sharing and toy play before and after training, and we also assessed infant attention and language. Mothers receiving book sharing training engaged well with it, and they also benefited from it; thus, compared to the comparison group mothers, they became more sensitive, more facilitating, and more elaborative with their infants during book sharing, and they also became more sensitive to their infants during toy play. In addition, infants whose mothers received the book sharing training showed greater benefits than the comparison group infants in both their attention and language. Training in book sharing for families living in conditions of marked socio-economic adversity in South Africa has the potential to be of considerable benefit to child developmental progress. A large scale controlled trial is required to confirm this.

A prolegomenon to the construct of the native speaker: heritage speaker bilinguals are natives too!

This Forum challenges the generally accepted position in the linguistic sciences—conscious or not—that monolingualism and nativeness are essentially synonymous in an exclusive way. We discuss two consequences of our position that naturalistic bilinguals and multilinguals exposed to a language in early childhood are also native speakers: (i) that bi-/multilinguals have multiple native languages;and (ii) nativeness can be applicable to a state of linguistic knowledge that is characterized by significant differences to the monolingual baseline.

Endocannabinoid signaling in autism

Autism spectrum disorder (ASD) is a complex behavioral condition with onset during early childhood and a lifelong course in the vast majority of cases. To date, no behavioral, genetic, brain imaging, or electrophysiological test can specifically validate a clinical diagnosis of ASD. However, these medical procedures are often implemented in order to screen for syndromic forms of the disorder (i.e., autism comorbid with known medical conditions). In the last 25 years a good deal of information has been accumulated on the main components of the “endocannabinoid (eCB) system”, a rather complex ensemble of lipid signals (“endocannabinoids”), their target receptors, purported transporters, and metabolic enzymes. It has been clearly documented that eCB signaling plays a key role in many human health and disease conditions of the central nervous system, thus opening the avenue to the therapeutic exploitation of eCB-oriented drugs for the treatment of psychiatric, neurodegenerative, and neuroinflammatory disorders. Here we present a modern view of the eCB system, and alterations of its main components in human patients and animal models relevant to ASD. This review will thus provide a critical perspective necessary to explore the potential exploitation of distinct elements of eCB system as targets of innovative therapeutics against ASD.

Good practice for pupils learning English as an additional language; lessons from effective literacy teachers in inner city primary schools.

This article presents observations and discussion of the successful teaching of English to pupils, in English primary schools, for whom English is an additional language (EAL). It draws on research in Year 2 (6/7year old) classes in three inner-city primary schools carried out in 2003 and 2005. Three recognised, effective teachers of literacy were selected for case study; all worked in successful schools where results for literacy, measured by national tests, were in line with or better than national averages. Following analyses of lesson observations and interviews with the teachers, their Headteachers and the EAL co-ordinators in the schools, a number of common elements in their practice emerged. Discussion centres on how these pedagogical features supported effective learning environments for the early literacy development of bilingual children, and on the implications for the practice of teaching English to all pupils.