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Background:Even infants can recognize whether patterns of motion are or are not natural, yet an acknowledged challenge for science education is to promote adequate reasoning about such patterns. Since research indicates linkage between the conceptual bases of recognition and reasoning, it seems possible that recognition can be engaged to support reasoning. Purpose:Noting the theoretical and practical significance of showing that recognition can support reasoning, the reported research aimed to examine the possibility in relation to horizontal motion. Sample:The research was conducted with 167 children (mean age = 9.51 years) from Years 4, 5 and 6 of an English-medium school located in Lisbon, Portugal. Design and methods:Individual pre-tests were administered to all participants to assess initial reasoning about the direction and speed with which rolling balls travel after collision. Reasoning was assessed in the sense of both predicting and explaining. Thereafter, about two-thirds of the sample worked with software that, via simulations of the incorrect patterns that were typically predicted (and comparison with simulations of correct patterns), engaged recognition as feedback on reasoning. The remaining children became an untutored control group. Replicating characteristic computer use in classrooms, half of the software sample worked as singletons with adult guidance available on request and half worked in pairs without the option of guidance. A few weeks later, all participants were post-tested following pre-test procedures. Results:Pre- to post-test change amongst the children who worked with the software exceeded pre- to post-test change within the control group, and this was observed with both predictions and explanations. The differences were strongest amongst the children who worked as singletons, even though they seldom requested adult support. Conclusions:Although issues remain to be addressed before the approach can be optimized, its viability as support for reasoning has been demonstrated, and this may have relevance beyond horizontal motion. [ABSTRACT FROM AUTHOR]

The conceptual understanding that children display when predicting physical events has been shown to be inferior to the understanding they display when recognizing whether events proceed naturally. This has often been attributed to differences between the explicit engagement with conceptual knowledge required for prediction and the tacit engagement that suffices for recognition, and contrasting theories have been formulated to characterize the differences. Focusing on a theory that emphasizes omission at the explicit level of conceptual elements that are tacitly understood, the paper reports two studies that attempt clarification. The studies are concerned with 6- to 10-year-old children's understanding of, respectively, the direction (141 children) and speed (132 children) of motion in a horizontal direction. Using computer-presented billiards scenarios, the children predicted how balls would move (prediction task) and judged whether or not simulated motion was correct (recognition task). Results indicate that the conceptions underpinning prediction are sometimes interpretable as partial versions of the conceptions underpinning recognition, as the omission hypothesis would imply. However, there are also qualitative differences, which suggest partial dissociation between explicit and tacit understanding. It is suggested that a theoretical perspective that acknowledges this dissociation would provide the optimal framework for future research. [ABSTRACT FROM AUTHOR]

When students reason during school science, they often refer to conceptions that are derived from out-of-school experiences and are poor proxies for science orthodoxy. However, for some areas of science, these conceptions represent only a proportion of students' full conceptual knowledge, for tacit understanding exists that is superior to the understanding displayed when reasoning. Noting that tacit understanding is engaged when events are judged as natural or non-natural, the paper is concerned with software that: (a) requires direction and speed of falling objects to be predicted, i.e. a typical science reasoning task that engages conceptual knowledge; (b) presents simulations of predicted motion in the expectation that its naturalness or non-naturalness would be recognised. An evaluation study is reported where children aged 8–12 years worked with the software in contexts that typify computer use in classrooms, i.e. individually under adult guidance (n  =  44 children) or in pairs with a classmate (n  =  48 children). They were observed while they did this. Reasoning about object fall was assessed via change from individual pre-tests administered prior to software usage to individual post-tests administered a few weeks afterwards. The children who worked with the software showed greater pre- to post-test gains in conceptual understanding than control children (n  =  47 children), who lacked software experience. The gains were especially marked for the children who worked in pairs. The approach taken is contrasted with traditional approaches to conceptual change in school science, e.g. strategies that rely upon classroom experiments. [ABSTRACT FROM PUBLISHER]

Objectives: Neuropsychological studies in subjects with bipolar disorder (BD) have reported deficits on a variety of cognitive measures. However, because the majority of subjects were medicated at the time of testing in previous studies, it is currently unclear whether the pattern of deficits reported is related to BD itself or to psychotropic medication. We addressed this issue by examining cognitive performance in a group of unmedicated, currently depressed subjects with BD. Methods: Forty-nine unmedicated subjects who met DSM-IV criteria for BD, depressed phase, and 55 control subjects participated in this study. Most patients were diagnosed with bipolar II disorder. Performance on emotion-dependent, or ‘hot’, and emotion-independent, or ‘cold’, cognitive tasks was assessed using tests from the Cambridge Neuropsychological Test Automated Battery. Results: The groups were well matched with respect to general intelligence and demographic variables. Deficits in the unmedicated depressed BD group were apparent on tests tapping ‘hot’ cognitive processing, for example the Cambridge Gamble task and the Probabilistic Reversal Learning task. However, other than a deficit on the Spatial Span test in the depressed BD subjects, the groups performed equivalently on most measures of ‘cold’ cognitive processing, for example visual memory, attention, and working memory. Conclusions: These data suggest that deficits on tests involving reward processing, short-term spatial memory storage, and sensitivity to negative feedback in depressed BD subjects represent an effect of the illness itself and not mood-stabilizing medication. [ABSTRACT FROM AUTHOR]