Mirror symmetry opposes splitting of chromatically homogeneous surfaces

Chromatically homogeneous surfaces can be seen as single figures but also as two or more overlapping figures. Local factors such as relatability have been proposed in order to explain perception of two or more figures (Kellman and Shipley, 1991 Cognitive Psychology 23 141-221). However, even when these factors are at work, there are conditions favouring the perception of a single figure, which have not been explored so far. Here we propose that one such factor is the mirror symmetry of the surface. Three experiments were designed to test: (a) the main hypothesis, that mirror symmetry enhances perception of a single figure; (b) the role of orientation; (c) the effect of the number of axes of symmetry. The results show that (i) there is a good general correlation between mirror symmetry and perception of a single figure; (ii) vertical and horizontal axes of symmetry are the most effective; and (iii) the more axes of symmetry a surface has, the more likely is the perception of a single figure. These results suggest that mirror symmetry is an important factor in the perception of chromatically homogeneous displays. Some explanations are discussed, particularly one based on the rejection-of-coincidence principle [Rock, 1983 The Logic of Perception (Cambridge, MA: MIT Press)], and a version of the minimum principle in which the strength of the global solution depends on symmetry, whereas the strength of the splitting solution depends on the strength of local factors. In brief, global and local factors compete in determining the perceptual outcome in chromatically homogeneous surfaces.     

儿童的几何图形预期表象

将儿童几何图形预期表象分为两种水平,即再认水平的预期表象和生成水平的预期表象。采用“平移”、“对称”、“重叠”三种平面几何图形的预期表象作业和“展开”、“旋转”、“截面”三种立体几何图形的预期表象作业考察了3至12岁儿童几何图形预期表象的发生和发展。结果表明：儿童再认预期表象的发生早于生成预期表象的发生;儿童预期表象的发生和发展明显受几何图形类型和作业类型的制约     

Retinal projection or size constancy as determinants of the horizontal-vertical illusion?

To compare the influence of the projected retinal size and of the figure size on the perception of the horizontal-vertical illusion, the target size, the viewing distance, and the slant of an illusion figure were varied. In the first experiment the illusion produced by two figures of the same object size but of different retinal size was compared with that of two figures projecting the same retinal size but differing in object size. The illusion diminished when the size of the retinal projection was increased, whereas a change in figure size did not change the illusion. In Exp. II the illusion figure was tilted backwards which reduced the retinal projection of the 'vertical' figure limb. The illusion decreased and became negative as a function of the retinal projection, but this decrease was relatively small compared with the reduction of the retinal image. The results are interpreted as supporting a retinal origin as an explanation of the illusion. Although there is strong evidence for size-constancy scaling in a tilted figure, constancy scaling is considered of minor importance as a determinant of the usual illusion.     

The development of enemy images in Dutch children: Measurement and initial findings

While there is ample evidence that enemies and enemy images are prerequisites in preparedness for war, little information is available about children's understanding of enemies or the presence of enemy images. Based on a pilot study in which assessment instruments were developed and validated, the present study examined the understanding of enemies and the presence of enemy images in 221 Dutch children aged between 7 and 12 years. The instruments employed involved the request to draw an enemy and an individual interview. Contrary to the expectation that younger children's enemy images would consist primarily of fictitious, non-human figures, whereas older children's images would focus more on realistic others as enemies, the findings revealed an opposite developmental course: younger children perceived enemies more often as concrete others, while older children perceived enemies more often as non-human, fictitious others. In addition, an age-related increase in children's experienced threats that cannot be reduced to concrete external causes was observed. Taken together with a growing awareness that enemies are characterized primarily by internal personality characteristics, latent (undefined) enemy images may easily become concrete enemies when an external focus is provided.     

Perceptions of body image among Japanese and Croatian children of preschool age

This study examined the differences in current and ideal body size among 108 Japanese and 129 Croatian preschool children (M=4.9 yr.). Boys and girls in both samples showed similarities by selecting the figure representing their current body size. Significant sex differences were found in selection of an ideal figure in the Japanese sample but not in the Croatian group. Japanese girls showed greater preference for a thinner figure than boys. In selection of an ideal body size significant cultural differences were found only for boys: Japanese boys preferred thinner figures. Results relating to body discrepancy (Current minus Ideal figures) indicated that there were fewer satisfied Japanese girls than Croatian girls whereas for the boys, a significantly larger number of Japanese than Croatian boys wished to be heavier.     

Errors towards the perpendicular in children's copies of angular figures: a test of the bisection interpretation

Children distort angular figures so that the constituent angles are nearer 90 degrees than they should be. This could be due to a perpendicular bias or a bisection bias, or to both. A study is reported which was designed to establish whether a perpendicular bias would appear independently of bisection. Twenty four-year-old children were tested on two types of angular figure: (i) a baseline with another line joining at the end at 45 degrees, 90 degrees, or 135 degrees and (ii) a baseline with another line joining at the middle at 45 degrees or 90 degrees. Perpendicular errors were obtained both for 'end' and for 'middle' figures, but overall more strongly for 'middle' figures. However, while 90 degrees 'middle' figures were copied more accurately than 45 degrees/135 degrees figures, this effect was only obtained for vertical and horizontal presentations of 'end' figures, and was reversed for oblique presentations. Also, for 'end' figures, directional errors varied with subtended-line orientation, whereas for 'middle' figures they varied with baseline orientation. It is concluded that although errors towards the perpendicular do occur with single-angle figures, angle equalisation may take place when there are two adjacent angles in the figure. One interpretation of the differing orientation effects is that in 'middle' figures strong internal relational forces produce a distortion that varies with the angle at which the figure is viewed, whereas in 'end' figures the absence of relational forces within the figure leads to a stronger influence from external cues.     

弱智儿童心理旋转的研究

该研究探讨了一组9~12岁弱智儿童的“心理旋转”能力,该组儿童平均年龄10.1岁,平均智商（IQ）53.8（中度智力残疾）。研究结果与正常儿童（均龄8岁）作了比较。结果显示,弱智儿童的心理旋转能力明显较之正常儿童为差,智力缺陷对视觉图形空间定向能力（心理旋转）有着明显的影响。但无论弱智儿童或是正常儿童的结果均未发现性别差异。     

Temperamental surgency and emotion regulation as predictors of childhood social competence

The primary aims of the current study were to longitudinally examine the direct relationship between children's temperamental surgency and social behaviors as well as the moderating role of children's emotion regulation. A total of 90 4.5-year-old children participated in a laboratory visit where children's temperamental surgency was rated by experimenters and children's emotion regulation abilities were assessed. The summer before entry into first grade, children's social behaviors with unfamiliar peers were observed in the laboratory and mothers completed a questionnaire about children's social behaviors. Supporting our hypotheses, results revealed that children high in temperamental surgency developed more negative peer behaviors, whereas children low in temperamental surgency were more likely to develop behavioral wariness with peers. Emotion regulatory behaviors were found to moderate the relation between temperamental surgency and aggression, where high-surgent children who showed high levels of social support seeking were less likely to be rated by their mothers as high in aggression. Furthermore, results revealed that low-surgent children who showed high levels of distraction/self-soothing were more likely to show behavioral wariness around unfamiliar peers, whereas high-surgent children who used more distraction/self-soothing behaviors were rated by their mothers as lower in social competence.     

Sex differences in proxemic behavior and personal space schemata in young children

Spatial preferences with feltboard figures, observed interpersonal distance, and sex-role identification were examined in 80 preschool children. On the feltboard measure, 4- to 5-year-olds chose generally greater interpersonal distance than younger children. Sex of stimulus figure also influenced older children's distance choices. When same-sex pair play was videotaped, older boys spent significantly more time at far distances and less time at close distances than younger boys. A positive correlation between sex-role identification, measured by the Rabban toy choice task, and feltboard figure distance was obtained for older boys only. Findings supported the notion that sex-related interpersonal spatial norms may be learned during the preschool years, particularly by boys.This study is based on a doctoral dissertation written by the author and submitted in partial fulfillment of the requirements for the Ph.D. degree at Michigan State University, 1974.     

Return of the Candy Witch: Individual differences in acceptance and stability of belief in a novel fantastical being

Recent research indicates that preschoolers make sophisticated choices in accepting testimony as a source of knowledge. Nonetheless, many children accept fantastical beings as real based on misleading testimony. The present study probes factors associated with belief in a novel fantastical figure, the Candy Witch, that 3‐ to 7‐year‐olds heard about at school. Short‐term belief was predicted by an interaction of age, existing beliefs in fantastical figures, and whether the child was ‘visited’ by the Candy Witch. Stability of belief was assessed over the course of 3 weeks and again 1‐year later. First year results revealed three patterns of belief: stable belief, wavering belief and stable non‐belief. First year belief status was not related to age, but older children from the stable belief group were more likely than younger children to disbelieve 1‐year later. The discussion presents a new proposal for the trajectory from belief to disbelief and an updated perspective on the role of individual differences in belief.     

儿童、中青年及老年人心理旋转能力的比较研究

采用12套不同视觉形状图形,探讨了儿童(7—9岁,均龄8岁)、中青年(23—47岁,均龄31．3岁)及老年人(61—79岁,均龄65．6岁)的心理旋转能力。结果表明不同年龄段被试的心理旋转能力存在明显差异。无论是对图形方位匹配判断的准确性还是完成判断任务的速度,中青年组被试的成绩均明显优于其他两组被试。儿童组被试在完成判断的速度上明显优于老年组,但在准确性方面两者不存在明显差异。各个年龄组的成绩均不存在性别差异。     

Assessing anti-fat bias in preschoolers: a comparison of a computer generated line-drawn figure array and photographic figure array

This study examined differences in preschoolers' ratings of anti-fat bias and identification of current body size depending on the realism of the figure array used: computer generated line-drawn or photographic. Children reported strong anti-fat bias with both arrays. However, less extreme bias was elicited with the photographic figure array. In addition, children were inaccurate reporters of their current body size when both figure arrays were used. However, children were consistent in their selection of figures that were thinner than their actual body size. Children's consistent selection of thinner figures as representative of their current body size may be an additional indicator of anti-fat bias. Overall, these results suggest that some of the anti-fat bias observed in preschoolers is attributable to less realistic figure arrays. Therefore, photographic figure arrays are proposed as a better measurement tool in the assessment of anti-fat bias in preschoolers.     

An exploratory study of the draw-a-person as a measure of racial identity.

The race of the figure drawn on the Draw-A-Person Test is proposed as a measure of acceptance of racial identity. Reliability and validity of this measure were explored in a two-part study. Part 1 confirmed the hypothesis that the race of the figure drawn is related to the race of the child producing the drawing. Comparison of the figures drawn by black (n = 157) and white (n = 167) children confirmed three other hypotheses based on the voluminous literature suggesting that black children are less accepting of their racial group membership than whites. These hypotheses were: (a) whites should be more likely to draw figures that are clearly white than blacks are to draw figures that are clearly black, (b) whites should be less likely to draw blacks than blacks are to draw whites, and (c) blacks should be more likely to avoid giving clear indication of the race of the figures they draw than are whites. Inter-rater reliability for the race of the figure drawn was .79. Five weeks after the initial drawing, a subsample of 28 black children drew a second figure and performed a picture choice task designed to assess acceptance of racial identity. The race of the figure drawn showed a test-retest reliability of .53 and correlated significantly with the other measure of racial identity (r27 = .39).     

Obesity Bias in Children: The Role of Actual and Perceived Body Size

The aim of this study was to examine how children perceive their body size and whether their actual or perceived body size can explain their anti‐fat views. Four hundred and fourteen 5–6, 7–8 and 9–10‐year‐old children were read short vignettes depicting two characters, one possessing a positive and the other a negative quality. Following each vignette, participants were asked to pick the story characters among thin, average and obese figures. Obesity bias was defined as the attribution of the positive quality to the thin or average figure and the corresponding negative one to the obese. Body mass index determined children's actual body size. Perceived body size was determined with the use of Collins' (1991) figures of increasing size. The results showed that actual body size affected the accuracy of perceived body size. While the majority of average children were accurate at identifying their body size, most overweight and obese children tended to underestimate it. The accuracy of body size perception improved with age. Obesity bias did not relate to children's actual but to their perceived body size: Those who perceived themselves as heavier exhibited less bias. The implications of the findings are discussed in relation to children's developing identity, and suggestions are made for future research. Copyright © 2014 John Wiley & Sons, Ltd.     

Weight attitudes in 3- to 5-year-old children: Age differences and cross-sectional predictors

We examined weight attitudes in 118 3- to 5-year-old girls and boys. Children completed an interview in which they were asked to select a figure to represent a child with positive or negative characteristics from an array of figures varying from very thin to large, and also a figure representing their own perceived size. Mothers’ body dissatisfaction, internalization of the thin ideal and dieting were assessed. Children chose larger figures to represent negative compared to positive characteristics. The figure size selected for negative characteristics was significantly greater in 5- than 3-year-olds but there was no age variation in figure size selected for positive characteristics. Children's own perceived body size positively predicted the figure size selected for positive characteristics. Maternal body image attitudes predicted figure size selection for both positive and negative characteristics. Findings suggest children's social environments are important in the development of negative and positive weight attitudes.     

Young children's change in strategies of size comparison: Effects of task repetition and strategy evaluation

This study examined how young children change their strategies for size comparison. Twenty-two 5 and 6-year-old children were asked to compare the sizes of geometric figures and their strategies were observed once a week over three weeks. Half of the children were also asked to evaluate presented strategies for comparing geometric figures. It was found that over three weeks not only children who evaluated the strategies but also children who did not increased correct responses, the strategy of placing one figure on another, and the strategy of adjusting two figures by two dimensions. Although more children became aware of the effectiveness of those strategies, there was no relationship between the evaluation and use of strategies.     

Development of Bimanual Skill: The Search for Stable Patterns of Coordination

In 2 experiments, dynamic systems theory predictions concerning intrinsic dynamics and variability of bimanual coordination were examined at different developmental stages. In Experiment 1, ten 4-, 6-, 7-, 8-, and 10-year-old children and adults performed unimanual dominant, unimanual nondominant, and bimanual continuous circle drawing. All tasks were performed at the participants' preferred rate, size, and mode of coordination. The 4-, 6-, and 7-year-old children produced larger circles with longer durations than those of the 8- and 10-year-olds and the adults. That finding demonstrates that younger children display different intrinsic dynamics than older children and adults. The 4-, 6-, and 7-year-old children also displayed more variability in bimanual coordination (more time in less stable patterns of coordination, higher standard deviation in relative phase) and produced more transitions between coordination patterns than the 8- and 10-year-olds and the adults. In Experiment 2, the same participants performed bimanual circles at increasing rates. Consistent with predictions of the HKB model (H. Haken, J. A. S. Kelso, & H. Bunz, 1985), the number of transitions decreased as speed increased. Some support was found for the notion that age-related variables of attention and rate contribute to the increased variability in young children's bimanual coordination.     

Development of bimanual skill: the search for stable patterns of coordination

In 2 experiments, dynamic systems theory predictions concerning intrinsic dynamics and variability of bimanual coordination were examined at different developmental stages. In Experiment 1, ten 4-, 6-, 7-, 8-, and 10-year-old children and adults performed unimanual dominant, unimanual nondominant, and bimanual continuous circle drawing. All tasks were performed at the participants' preferred rate, size, and mode of coordination. The 4-, 6-, and 7-year-old children produced larger circles with longer durations than those of the 8- and 10-year-olds and the adults. That finding demonstrates that younger children display different intrinsic dynamics than older children and adults. The 4-, 6-, and 7-year-old children also displayed more variability in bimanual coordination (more time in less stable patterns of coordination, higher standard deviation in relative phase) and produced more transitions between coordination patterns than the 8- and 10-year-olds and the adults. In Experiment 2, the same participants performed bimanual circles at increasing rates. Consistent with predictions of the HKB model (H. Haken, J. A. S. Kelso, & H. Bunz, 1985), the number of transitions decreased as speed increased. Some support was found for the notion that age-related variables of attention and rate contribute to the increased variability in young children's bimanual coordination.     

Distortions in memory for maps

Evidence is presented for systematic errors in memory for real and artificial maps, local environments, and visual forms. These errors are attributed to two heuristics that are derived from principles of perceptual organization. Maps of countries or localities are conceived of as figures in backgrounds. Remembering the absolute location of figures is difficult, and is facilitated by remembering locations relative to other figures and/or relative to the natural directions of the figure. In alignment, figures are lined up relative to one another, a phenomenon related to perceptual grouping by proximity. In rotation, the natural axes induced by a figure converge with frame axes (north-south, east-west, or horizontal, vertical), a phenomenon related to perceptual organization by common fate. Heuristic-induced errors occur in a variety of tasks, and even when subjects are explicitly forewarned. These heuristics may be invoked in forming representations as well as in inference, and function analogously to syntax in locating smaller elements in larger units.     

Tracking and inferring spatial rotation by children and great apes

Finding hidden objects in space is a fundamental ability that has received considerable research attention from both a developmental and a comparative perspective. Tracking the rotational displacements of containers and hidden objects is a particularly challenging task. This study investigated the ability of 3-, 5-, 7-, and 9-year-old children and great apes (chimpanzees, bonobos, gorillas, and orangutans) to (a) visually track rotational displacements of a baited container on a platform and (b) infer its displacements by using the changes of position or orientation of 3 landmarks: an object on a container, the color of the containers, and the color of the platform on which the containers rested. Great apes and 5-year-old and older children successfully tracked visible rotations, but only children were able to infer the location of a correct cup (with the help of landmarks) after invisible rotations. The ability to use landmarks changed with age so that younger children solved this task only with the most explicit marker on the baited container, whereas older children, particularly 9-year-olds, were able to use landmark orientation to infer correct locations.