Imagery and explanation in the dynamics of recall of intuitive and scientific knowledge : insights from research on children's cosmologies

This article closely examines (a) the representational connotation which is often implicit in many analyses of the scientific knowledge which children have (or have not) acquired when they are asked to say or show what they know and (b) the still common-place presumption that recollections are akin to the extraction of ideas from a mental database. We demonstrate how recent findings in neuroscience reject traditional thinking about the nature of ‘representation’ and the character of associated imagery and verbal explanation. Researchers have to contend with the fact that concepts must be regarded as flexible, and that memory is dynamic. Such considerations emphasise the creative, rather than the reproductive, nature of remembering, thus calling into question the status of what is thought to be ‘grasped’ and ‘imaged’ by those being interviewed, possibly casting some doubt on the status of children’s conceptions (and misconceptions) and the categories into which these are sometimes placed in schematic depictions of their understanding. Examples from research on children’s cosmologies are used to illustrate the discussion. It is argued that science education researchers endeavouring to uncover what children know, intuitively and scientifically, through interviewing them, face a reconsideration of the theoretical underpinnings to much of their work

Manipulating models and grasping the ideas they represent

This article notes the convergence of recent thinking in neuroscience and grounded cognition regarding the way we understand mental representation and recollection: ideas are dynamic and multi-modal, actively created at the point of recall. Also, neurophysiologically, re-entrant signalling among cortical circuits allows non-conscious processing to support our deliberative thoughts and actions. The qualitative research we describe examines the exchanges occurring during semi-structured interviews with 360 children age 3–13, including 294 from New Zealand (158 boys, 136 girls) and 66 from China (34 boys, 32 girls) concerning their understanding of the shape and motion of the Earth, Sun and Moon (ESM). We look closely at the relationships between what is revealed as children manipulate their own play-dough models and their apparent understandings of ESM concepts. In particular, we focus on the switching taking place between what is said, what is drawn and what is modelled. The evidence is supportive of Edelman’s view that memory is non-representational and that concepts are the outcome of perceptual mappings, a view which is also in accord with Barsalou’s notion that concepts are simulators or skills which operate consistently across several modalities. Quantitative data indicate that the dynamic structure of memory/concept creation is similar in both genders and common to the cultures/ethnicities compared (New Zealand European and Māori; Chinese Han) and that repeated interviews in this longitudinal research lead to more advanced modelling skills and/or more advanced shape and motion concepts, the results supporting hypotheses (Kolmogorov–Smirnov alpha levels.05; rs: p < .001)

Switching between everyday and scientific language

The research reported here investigated the everyday and scientific repertoires of children involved in semi-structured, Piagetian interviews carried out to check their understanding of dynamic astronomical concepts like daytime and night-time. It focused on the switching taking place between embedded and disembedded thinking; on the imagery which subjects referred to in their verbal dialogue and their descriptions of drawings and play-dough models of the Earth, Sun and Moon; and it examined the prevalence and character of animism and figurative speech in children’s thinking. Five hundred and thirty-nine children (aged 3–18) from Wairarapa in New Zealand (171 boys and 185 girls) and Changchun in China (99 boys and 84 girls) took part in the study. Modified ordinal scales for the relevant concept categories were used to classify children’s responses and data from each age group (with numbers balanced as closely as practicable by culture and gender) analysed with Kolmogorov-Smirnov two-sample tests (at an alpha level of 0.05). Although, in general, there was consistency of dynamic concepts within and across media and their associated modalities in keeping with the theory of conceptual coherence (see Blown and Bryce 2010; Bryce and Blown 2016), there were several cases of inter-modal and intra-modal switching in both cultures. Qualitative data from the interview protocols revealed how children switch between everyday and scientific language (in both directions) and use imagery in response to questioning. The research indicates that children’s grasp of scientific ideas in this field may ordinarily be under-estimated if one only goes by formal scientific expression and vocabulary

The enduring effects of early-learned ideas and local folklore on children's astronomy knowledge

The research described here examined the sources of knowledge of astronomy of children (age 3-18) in China and New Zealand, together with the development of their awareness of competing sources, ranging from everyday language, childhood literature and folklore to the scientific accounts prevalent in schools. The authors cite examples of the bootstrapping encountered during these years, where children’s expanding knowledge and how they process questions intended to probe their understandings – their meta-cognitive strategies – are mutually beneficial. The semi-structured interviews utilising three modalities (verbal language, drawing and play-dough modelling) carried out with pupils (n=358), and questionnaires administered to their parents (n=80), teachers (n=65), and local librarians (n=5), focused on young people’s understanding of daytime and night-time and the roles played by the Sun and Moon in creating familiar events. The findings underscore the arguments put forward by the authors in a recent article in this journal concerning the co-existence of everyday and scientific concepts. The influence of early-learned ideas deriving from pre-school experiences, recalled by children and largely corroborated by family members, was found to be extensive. Evidence of the migration of folklore in one of the two settings investigated (on the North East China Plain) and therefore its continuing influence on children’s comprehension is provided. With respect to teaching, the authors argue the benefits to be had in making more explicit with young students the differences between early-learned (everyday-cultural) ideas – particularly local community knowledge and folklore – and the scientific content found in the school curriculum

Ausubel's meaningful learning re-visited

This review provides a critique of David Ausubel’s theory of meaningful learning and the use of advance organizers in teaching. It takes into account the developments in cognition and neuroscience which have taken place in the 50 or so years since he advanced his ideas, developments which challenge our understanding of cognitive structure and the recall of prior learning. These include (i) how effective questioning to ascertain previous knowledge necessitates in-depth Socratic dialogue; (ii) how many findings in cognition and neuroscience indicate that memory may be non-representational, thereby affecting our interpretation of student recollections; (iii) the now recognised dynamism of memory; (iv) usefully regarding concepts as abilities or simulators and skills; (v) acknowledging conscious and unconscious memory and imagery; (vi) how conceptual change involves conceptual coexistence and revision; (vii) noting linguistic and neural pathways as a result of experience and neural selection; and (viii) recommending that wider concepts of scaffolding should be adopted, particularly given the increasing focus on collaborative learning in a technological world

Semi-analytic method for slow light photonic crystal waveguide design

We present a semi-analytic method to calculate the dispersion curves and the group velocity of photonic crystal waveguide modes in two-dimensional geometries. We model the waveguide as a homogenous strip, surrounded by photonic crystal acting as diffracting mirrors. Following conventional guided-wave optics, the properties of the photonic crystal waveguide may be calculated from the phase upon propagation over the strip and the phase upon reflection. The cases of interest require a theory including the specular order and one other diffracted reflected order. The computational advantages let us scan a large parameter space, allowing us to find novel types of solutions.Comment: Accepted by Photonics and Nanostructures - Fundamentals and Application

Some Assembly Required: How Scientific Explanations are Constructed During Clinical Interviews

This article is concerned with commonsense science knowledge, the informally-gained knowledge of the natural world that students possess prior to formal instruction in a scientific discipline. Although commonsense science has been the focus of substantial study for more than two decades, there are still profound disagreements about its nature and origin, and its role in science learning. What is the reason that it has been so difficult to reach consensus? We believe that the problems run deep; there are difficulties both with how the field has framed questions and the way that it has gone about seeking answers. In order to make progress, we believe it will be helpful to focus on one type of research instrument – the clinical interview – that is employed in the study of commonsense science. More specifically, we argue that we should seek to understand and model, on a moment-by-moment basis, student reasoning as it occurs in the interviews employed to study commonsense science. To illustrate and support this claim, we draw on a corpus of interviews with middle school students in which the students were asked questions pertaining to the seasons and climate phenomena. Our analysis of this corpus is based on what we call the mode-node framework. In this framework, student reasoning is seen as drawing on a set of knowledge elements we call nodes, and this set produces temporary explanatory structures we call dynamic mental constructs. Furthermore, the analysis of our corpus seeks to highlight certain patterns of student reasoning that occur during interviews, patterns in what we call conceptual dynamics. These include patterns in which students can be seen to search through available knowledge (nodes), in which they assemble nodes into an explanation, and in which they converge on and shift among alternative explanations

Pulsations, eruptions, and evolution of four yellow hypergiants

We aim to explore the variable photometric and stellar properties of four yellow hypergiants (YHGs), HR8752, HR 5171A, $\rho$ Cas, and HD 179821, and their pulsations of hundreds of days, and long-term variations (LTVs) of years. We tackled multi-colour and visual photometric data sets, looked for photometric indications betraying eruptions or enhanced mass-loss episodes, calculated stellar properties mainly using a published temperature calibration, and investigated the nature of LTVs and their influence on quasi-periods and stellar properties. The $BV$ photometry revealed a high-opacity layer in the atmospheres. When the temperature rises the mass loss increases as well, consequently, as the density of the high-opacity layer. As a result, the absorption in $B$ and $V$ grow. The absorption in $B$, presumably of the order of one to a few 0\fm1, is always higher than in $V$. This difference renders redder and variable $(B-V)$ colour indexes, but the absorption law is unknown. This property of YHGs is unpredictable and explains why spectroscopic temperatures are always higher than photometric ones. We propose shorter distances for $\rho$ Cas and HR 5171A than the accepted ones. Therefore, a correction to decrease the blue luminescence of HR 5171A by polycyclic aromatic hydrocarbon (PAH) molecules is necessary, and HR 5171A would no longer be a member of the cluster Gum48d. HR 5171A is only subject to one source of light variation, not by two as the literature suggests. Eruptive episodes of YHGs prefer relatively cool circumstances when a red evolutionary loop (RL) has shifted the star to the red on the HR diagram. After the eruption, a blue loop evolution (BL) is triggered lasting one to a few decades. The reddening episode of HR 5171A between 1960 and 1974 was most likely due to a red loop evolution, and the reddening after the 1975 eruption was likely due to a shell ejection.Comment: 28 pages, 18 figures, Accepted for Astronomy and Astrophysic

An assessment of the Colombian government's commitment to the goal of universal primary education

Universal primary education is the goal of many developing countries. It is a high priority in the educational planning of Colombia. The law in Colombia states that five years of 'educación primaría' is free and compulsory. Since 1955, Colombia has investigated the problems and legislated reforms to make this law an actual fact. In Latin America, reform laws and planning studies very often remain just that: the implementation of the reforms is delayed or forgotten in the maze of planning boards and government offices. This thesis examines the reforms passed by the Colombian government in the period 1955 to 1965, and assesses their implementation in public primary education. The problems that were encountered in the attempts to achieve the goal of universal primary education are studied, and the effects of the continued emphasis on the expansion of primary education are discussed in the conclusion. The information for the study was derived primarily from secondary sources, as the original Ministry of Education reports were not available. The Colombian government and United Nations statistics were used to make conclusions about the 1965 situation of primary education. The most recent comprehensive statistics were from the 1965 census. A general view of Colombia was gained from a short stay (one month) in 1970, and, a discussion with a Colombian, who visited Canada in 1972, helped to give some insight into the country's educational problems. Universal primary education was still an ideal in Colombia in 1965. Many of the reforms, because of governmental bureaucracy and the economic situation were only partially implemented. There was a percentage increase in enrollment statistics and the government demonstrated its commitment to the goal by increasing the educational budget. Generally, the targets set by the government were too optimistic; the ideals expressed in political statements were far from reality. The thesis concludes that there are two options for the educational planners of Colombia: the first, to continue to aim for the goal of universal primary education, devoting a large percentage of the budget to the primary sector, with little hope of achieving this goal in the immediate future, and the second, to distribute the money available throughout the education system to enable a greater segment of the population to obtain secondary education and thus increase the middle class, but, at the same time, accepting the fact that a proportion of the population would remain illiterate.Arts, Faculty ofFrench, Hispanic, and Italian Studies, Department ofGraduat