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Accès au langage et raisonnement de type théorie de l'esprit: recherches avec des enfants sourds signeurs natifs Ce commentaire a pour objectif de souligner les aspects fondamentaux des résultats récents concernant le raisonnement de type théorie de l'esprit (TOM) chez les jeunes enfants et ses relations avec l'accès au langage. Â maints égards, il apparaît désormais clairement que le raisonnement de type TOM et plus généralement les aspects de la mentalisation qui lui sont associés comme la compréhension des émotions, sont indépendants de l'acquisition de la syntaxe et d'autres aspects du langage, mais sont liés par contre à l'utilisation du langage comme base de discussion à propos des états mentaux. Les recherches avec les enfants sourds signeurs natifs et issus de familles de sourds sont particulièrement démonstratives de ce point de vue. Avec des environnements langagiers similaires à la maison, les enfants signeurs natifs bilingues qui ont accès à la fois au langage signé et au langage parlé à l'école ont des performances en TOM bien supérieures aux enfants qui sont dans des écoles oralistes où l'accès au langage signé est absent. De tels résultats suggèrent que l'expression d'une TOM chez les signeurs natifs pourrait être stimulée par la pratique et l'automatisation, dans un environnement où l'accès au langage natif (naturel) est continu. Dans ce cas, les enfants ont des conditions optimales pour maîtriser les aspects de la conversation portant sur les états mentaux avec toutes les implications qui en découlent dans l'évaluation métareprésentationnelle, et en particulier les états épistémiques de croyance vraie ou fausse.

According to Piagetian accounts of cognitive development, children's responses on many tasks reflect the lack of evidence for an operational competence that is conceptual rather than linguistic. In this paper, I show that such accounts assume that young children are endowed with substantial conversational wizardry, allowing them to interpret questions about cognitive tasks as intended by the experimenter. Once it is explicitly recognized that children may be less advanced in their conversational awareness than is commonly assumed, their competence can be assessed more accurately. Recent and new evidence from a variety of sources, such as research on conservation, suggestibility in memory, and theory of mind understanding in deaf and hearing children, converges to indicate that competence is inadequately characterized by a dichotomy between pre‐operational and operational logic and that what is developing in children's cognition is a complex interplay between both conversational and conceptual processes. This evidence is not merely relevant to methodological concerns. It demands a radical shift in cognitive developmental theory and research to account for the importance of children's conversational awareness.

AbstractIn three experiments involving 207 preschoolers and 28 adults, we investigated the extent to which young children base moral judgments of actions aimed to protect others on utilitarian principles. When asked to judge the rightness of intervening to hurt one person in order to save five others, the large majority of children aged 3 to 5 years advocated intervention in contrast to another situation with the reverse cost/benefit ratio. This course of action was seen as acceptable by most children only when it did not require the agent to have physical contact with the victim and the victim's harm was intended to produce the greatest good for the greatest number. Overall, the children's responses were remarkably similar to those reported in adult studies. These findings document the extent to which some constraints on moral judgment are present in early human development.

Abstract In this investigation, we examined children's knowledge of cosmology in relation to the shape of the earth and the day‐night cycle. Using explicit questioning involving a choice of alternative answers and 3D models, we carried out a comparison of children aged 4–9 years living in Australia and England. Though Australia and England have a close cultural affinity, there are differences in children's early exposure to cosmological concepts. Australian children who have early instruction in this domain were nearly always significantly in advance of their English counterparts. In general, they most often produced responses compatible with a conception of a round earth on which people can live all over without falling off. We consider coherence and fragmentation in children's knowledge in terms of the timing of culturally transmitted information, and in relation to questioning methods used in previous research that may have underestimated children's competence.

We report two studies designed to examine the role of conversational understanding in young children's scientific reasoning. The results indicate that performance can be influenced by the degree of specificity in questioning. Under nonspecific questioning, accurate reasoning was associated with both vocabulary comprehension and pragmatic ability whereas under specific questioning it was associated only with vocabulary comprehension. Findings are discussed in terms of the conversational knowledge that is required for success on measures of scientific reasoning.

AbstractBased on anticipatory looking and reactions to violations of expected events, infants have been credited with 'theory of mind' (ToM) knowledge that a person's search behaviour for an object will be guided by true or false beliefs about the object's location. However, little is known about the preconditions for looking patterns consistent with belief attribution in infants. In this study, we compared the performance of 17‐ to 26‐month‐olds on anticipatory looking in ToM tasks. The infants were either hearing or were deaf from hearing families and thus delayed in communicative experience gained from access to language and conversational input. Hearing infants significantly outperformed their deaf counterparts in anticipating the search actions of a cartoon character that held a false belief about a target‐object location. By contrast, the performance of the two groups in a true belief condition did not differ significantly. These findings suggest for the first time that access to language and conversational input contributes to early ToM reasoning.

AbstractChildren's understanding of properties of the earth was investigated by interviewing Asian and white British classmates aged 4−8 years (N = 167). Two issues were explored: whether they held mental models of the earth (Vosniadou & Brewer, 1992) or instead had fragmented knowledge (di Sessa, 1988); and the influence of the children's different cultural backgrounds. Children selected from a set of plastic models and answered forced‐choice questions. Using this methodology, there were no significant differences in the overall performance of Asian and white children after language skills were partialled out. Even young children showed an emerging knowledge of some properties of the earth, but the distributions of their combinations of responses provided no evidence that they had mental models. Instead, these distributions closely resembled those that would be expected if children's knowledge in this domain were fragmented. Possible reasons for the differences between these findings and those of previous research are discussed.

Neutron sensing is critical in civilian and military applications. Conventional neutron sensors are limited by size, weight, cost, portability and helium supply. Here the microfabrication of gadolinium (Gd) conversion material–based heterojunction diodes for detecting thermal neutrons using electrical signals produced by internal conversion electrons (ICEs) is described. Films with negligible stress were produced at the tensile-compressive crossover point, enabling Gd coatings of any desired thickness by controlling the radiofrequency sputtering power and using the zero-point near p(Ar) of 50 mTorr at 100 W. Post-deposition Gd oxidation–induced spallation was eliminated by growing a residual stress-free 50 nm neodymium-doped aluminum cap layer atop Gd. The resultant coatings were stable for at least 6 years, demonstrating excellent stability and product shelf-life. Depositing Gd directly on the diode surface eliminated the air gap, leading to a 200-fold increase in electron capture efficiency and facilitating monolithic microfabrication. The conversion electron spectrum was dominated by ICEs with energies of 72, 132 and 174 keV. Results are reported for neutron reflection and moderation by polyethylene for enhanced sensitivity, and γ- and X-ray elimination for improved specificity. The optimal Gd thickness was 10.4 μm for a 300 μm-thick partially depleted diode of 300 mm2 active surface area. Fast detection (within 10 min) at a neutron source-to-diode distance of 11.7 cm was achieved with this configuration. All ICE energies along with γ-ray and Kα,β X-rays were modeled to emphasize correlations between experiment and theory. Semi-conductor thermal neutron detectors offer advantages for field-sensing of radioactive neutron sources.