How to keep a reversible figure from reversing: teasing out top-down and bottom-up processes

The nature of processes underlying our perception of reversible figures was examined through two experiments investigating the effects of prior exposure conditions on an observer's report of figural reversal. In experiment 1, observers were adapted over several minutes to an unambiguous version of a rotating Necker cube prior to the presentation of the standard ambiguous figure. Results indicated that adaptation produced an immediate bias to perceive the ambiguous figure in the opposite configuration (ie reverse bias) and to reduce reports of reversal over the test period. The introduction of a brief delay between the adaptation and test periods revealed that this bias is a highly transient effect and is only clearly evident when the adaptation and test figures are matched in size. In experiment 2, observers were primed with an unambiguous figure for a few seconds prior to the presentation of the standard ambiguous figure. In this case, the obtained bias strongly favored the observer's reporting the ambiguous figure to be in the same configuration as the adapting figure (ie positive bias); and neither introducing a delay period nor changing figure size had any effect. We conclude that these experiments reveal the distinct roles of transient, retinally localized neural processes as well as more stable, global processes under specifiable conditions.     

Human figure drawing size and body image in preschool children from a self-physique perspective

To learn about the relationship between size of human figure drawings and the physiques of children, we investigated body image characteristics in childhood by using the Human Figure Drawing test. Height, weight, Kaup Index (a body mass index for children) and Human Figure Drawing traits (vertical height, horizontal width, waist size, surface area of head, surface area of the self-drawing) were measured for drawings of 122 4- to 6-yr.-old children (62 boys, 60 girls). Analysis showed that boys, who are physically larger than girls, produced self-drawings with somewhat larger surface areas. For vertical height of self-drawings of boys, 4-yr.-olds characteristically made taller self-drawings than 5-yr.-olds. While we hypothesized that taller children would make vertically taller self-drawings, we observed a negative relationship between children's physical height and the vertical height of the self-drawings. 4-yr.-old boys showed the most interest in their own physical height, making taller drawings and in doing so gave a clue to an early childhood feature of body image.     

As the cube turns: Evidence for two processes in the perception of a dynamic reversible figure

The reported reversals of a rotating Necker cube, which changes direction of rotation when a perspective reversal occurs, were examined under a number of conditions. These permitted comparisons of reversal rates within viewing periods, across successive viewing periods within an experimental session, and across successive weekly sessions. In addition, observers viewed either one or two rotating cubes simultaneously within each of the various viewing periods. Clear evidence for a learning effect was obtained in the form of significant savings across successive viewing periods and sessions. At the same time, results from the multiple-cube conditions and from the pattern of reversals within individual viewing periods appeared to be more consistent with a process of neural fatigue. A two-stage model of reversible-figure perception is proposed which is characterized by (1) fatiguing with extended viewing of the two sets of neural channels that underlie the two percepts of the reversible figure, and (2) learning, which helps to establish the organization of the cortical channels as well as moderate channel activity via such processes as attention and strategy.     

Studies of reversible perspective: A methodological review

The lack of an adequate theory of reversible perspective is largely attributable to the haphazard methodology adopted by many workers in this area of research. After more than 60 years, no standard experimental procedure has evolved, and the comparison of results from different studies is difficult. Some representative experiments are reviewed in terms of the temporal, stimulus, and procedural factors involved. It is suggested that the general use of the reversal rate measure is the major single barrier to progress, and that a continuous recording method be adopted in future experimentation.     

Satiation in name and face recognition

Massive repetition of a word can lead to a loss of meaning (i.e., semantic satiation). Satiation is a general property of neurons and so it would be expected that semantic satiation would be found for stimuli other than words. Three experiments examined the occurrence of satiation for the repetition of names, the visualization of faces, and the repetition of faces. Reaction times to a decision based on a repeated name or face were longer following 30 repetitions than following 3 repetitions, indicating that satiation had occurred. Mere visualization over the same time interval, however, did not elicit satiation effects.     

中文词汇加工中的饱和现象

长时间注视一个字或词语后,感觉这个字词变得奇怪且陌生,这种现象称为饱和现象。本研究采用快速类别/词汇匹配范式,考察中文词汇加工中的饱和现象。实验1-3发现单纯的语义或字形的重复均未能引发饱和,只有类别标签在字形和语义上的同时重复才引发饱和,表明与英文饱和相似,中文饱和发生在字形加工和语义加工的联结阶段。实验4结果表明,中文饱和还能够由表义部件的重复引发,体现了中文饱和的特殊性。     

语义饱和现象及其认知机制

大部分人有过长时间注视一个字之后突然不认识这个字,或多次重复背诵一个词语后会发现这个词变得“陌生”的经历.早期的心理学家发现在字词持续注意过程中语义会丢失,他们将这种现象命名为语义饱和.经过100多年的研究,众多心理学家发展了多种语义评价的方法来测量语义饱和,并发现语义饱和可能发生在知觉表征、语义加工或者词语表征与语义的联结阶段.类似的现象在中文等语标文字加工中表现出一种特有的字形饱和.近年来,新的认知心理学实验范式和神经科学技术的发展将有可能使得语义饱和研究取得重要的突破.     

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.