Perceptual assumptions and projective distortions in a three-dimensional shape illusion

We examine a shape illusion, in which the balconies of a building appear to tilt up or down, depending on the viewpoint. The balconies are actually level parallelogram shapes, but appear as tilted rectangles. We measured the illusory tilts observed when parallelogram shapes are viewed above the line of sight, using three-dimensional stimuli consisting of parallelograms of various tilts viewed at different orientations. Under perspective projection, parallelism and orthogonality are not preserved. However, perspective distortions alone cannot account for the perceived tilts measured in these experiments, since observers perceived illusory tilts even for stimuli in the frontoparallel plane. We introduce a model, based on the theory that observers assume ambiguously projected three-dimensional angles to be equal to 90 degrees, but revise their predictions on the basis of observation. In the model, perceived tilt is predicted as a weighted sum of the tilts predicted by the assumptions that the shape is rectangular, and that the shape is level (i.e. that the angle between the shape and the vertical backboard is equal to 90 degrees). We prove that it is mathematically impossible for a planar rectangle to share a projection with a nonrectangular parallelogram. A less restrictive assumption that just the two leading internal angles are equal to 90 degrees is suggested as an alternative, and it is further proven that this new configuration of angles leads to a unique perceived tilt. The relative weights in the model reflect the amount that each prediction is revised, and are shown to vary systematically with stimulus orientation. For some observers a better fit was found by replacing the level-tilt assumptions with an assumption that physical tilt was equal to the projected tilt.     

达米特论意义和真

达米特的反实在论意义理论在当代语言哲学中占据重要地位.本文主要分析了他对"意义"和"真"这两个概念的解释,指出他的意义理论完全是一种形式说明,或者说,是对意义理论本身的形式构造.同时,达米特反对用真值条件来解释意义,主要是根据他对"真"这个概念有着不同的理解:他把"真"看作我们在具体场合说出的句子的属性.达米特的思想受到了各方面的批评,他也在这种批评和反批评过程中不断完善自己的思想.     

Inhibition of return to occluded objects

Since many visual objects are vulnerable to occlusion, an active process that tracks objects behind occluders confers considerable ecological validity to the visual system. We studied this possibility by testing whether inhibition of return can be observed with occluded objects. In our experiments, two moving objects disappeared or reappeared behind occluders while a cue and a probe were presented. Contrary to the results of a previous study (Tipper, Weaver, Jerreat, & Burak, 1994), responses were consistently delayed for the cued object that was occluded when it was cued (Experiment 1), when it was probed (Experiment 2), or both (Experiment 3). These results suggest that attention can select occluded objects that are out of view. Our findings are in line with prior studies that have demonstrated similar perceptual/attentional effects for occluded objects, as well as for visible objects.     

Circadian phase-shifted rats show normal acquisition but impaired long-term retention of place information in the water task

It is thought that circadian rhythms may influence learning and memory processes. However, research supporting this view does not dissociate a mnemonic impairment from other performance deficits. Furthermore, published reports do not specify the type of memory system influenced by the circadian system. The present study assessed the effects of phase shifting on acquisition and expression of place navigation in the water maze, a task sensitive to hippocampal dysfunction. The results showed that phase-shifting circadian rhythms in rats impaired the expression of place information on a retention test but not initial acquisition or encoding of place information. These results suggest that disruption of circadian rhythms may impair consolidation of previously encoded hippocampal place information.     

Models of self and others and their relation to positive and negative caregiving responses

The burden of providing informal care to a family member can lead to caregiver depression and potentially harmful caregiving behavior. Given the interpersonal nature of caregiving, the relationship between caregivers and care recipients may impact caregiver responses. We applied attachment theory to understanding caregiver depression, and both potentially harmful and exemplary caregiving responses. We present data from 430 caregivers in the Family Relationships in Late Life (FRILL 2) Project, a multisite, longitudinal study of caregiving. Age, gender, and model of self were related to caregiving responses, suggesting that model of self may help identify caregivers at risk for poor responses.     

当代大学生创业意向影响因素研究

为了深入了解当代大学生的创业意向及其影响因素,研究者以全国30所高校5000多名大学生为被试,对影响大学生创业意向的诸多因素进行了分析。研究发现:当代大学生的创业意向在性别、奖学金获得次数、学生干部经历、出生地上均存在一定差异。大学生主客观条件中的性别、学校性质、创业兴趣、创意能力改善对创业意向有显著影响。创业教育和创业环境认知的引入对于预测大学生的创业意向均有增量效度,能够在个体的主客观条件以外解释个体创业意向的变异。在大学生认知中,影响创业成功的因素主要由客观背景资源、主观能力经验和外部宏观环境3个因子组成,其中主观能力经验的作用排在首位。     

传统药物治疗认识误区几点浅析

药物是治疗疾病的物质基础,传统药物治疗认识中的许多误区影响人们对疾病的合理治疗.积极宣传药物治疗新理念,普及现代药学知识和理论,提高广大人民群众对药物治疗的认识水平,是避免出现药物治疗认识误区的主要手段.应加强宣传力度,带领群众走出误区,促进合理用药.