Edge-induced illusory contours and visual detection: Subthreshold summation or spatial cueing?

Findings that illusory contours can facilitate visual detection of a subthreshold real line (Dresp & Bonnet, 1995) were not replicated, when line-induced instead of edge-induced illusory contour stimuli were used (Salvano-Pardieu et al., 2006). Rather, the results of the latter study supported the importance of spatial cues. The present study was designed to investigate whether spatial cueing might also facilitate detection of targets superimposed on edge-induced illusory contours. In Experiment 1, a target line was superimposed on the illusory contour of a Kanizsa square, presented between dots with a precise or distant location to the target, or on a homogeneous field (control). Detection of the target was poorest for the control, followed by the distant-dots and Kanizsa conditions, whereas it was best for precisely cueing dots. Experiment 2 replicated the conditions in Experiment 1 (Kanizsa, precisely cueing dots, and control) with additional controls for possible luminance effects. The two new conditions matched the Kanizsa condition for overall luminance and preciseness of spatial cueing without generating illusory contours. Performance was best in the dot condition and worst in the control, but the same across the Kanizsa and matched luminance conditions. In Experiments 3 and 4, the stimuli presented were matched more closely to those used by Dresp and Bonnet, but still the results confirmed those obtained in our Experiments 1 and 2. Together, these experiments strongly suggest that detection is also facilitated by spatial cueing rather than subthreshold summation, in the case of edge-induced illusory contours.     

Effects of element separation on perceptual grouping by humans (Homo sapiens) and chimpanzees (Pan troglodytes): perception of Kanizsa illusory figures

The processing of Kanizsa-square illusory figures was studied in two experiments with four humans and two chimpanzees. Subjects of the two species were initially trained to select a Kanizsa-square illusory figure presented in a computerized two-alternative forced choice task. After training, adding narrow closing segments to the pacman inducers that composed the Kanisza illusory figures lowered performance in both chimpanzees and humans, suggesting that the discrimination could be controlled by the perception of illusory forms. A second experiment assessed transfer of performance with five sets of figures in which the size of the inducers and their separation were manipulated. Only for chimpanzees was performance directly controlled by separation, suggesting that chimpanzees are more sensitive than humans to the separation between visual elements. Accepted after revision: 15 August 2001 Electronic Publication     

Better safe than sorry: Simplistic fear-relevant stimuli capture attention

It has been consistently demonstrated that fear-relevant images capture attention preferentially over fear-irrelevant images. Current theory suggests that this faster processing could be mediated by an evolved module that allows certain stimulus features to attract attention automatically, prior to the detailed processing of the image. The present research investigated whether simplified images of fear-relevant stimuli would produce interference with target detection in a visual search task. In Experiment 1, silhouettes and degraded silhouettes of fear-relevant animals produced more interference than did the fear-irrelevant images. Experiment 2, compared the effects of fear-relevant and fear-irrelevant distracters and confirmed that the interference produced by fear-relevant distracters was not an effect of novelty. Experiment 3 suggested that fear-relevant stimuli produced interference regardless of whether participants were instructed as to the content of the images. The three experiments indicate that even very simplistic images of fear-relevant animals can divert attention.     

Symbolization

Abstract

The starting point of this article is that the concept of “vitality affects” is, on the one hand, very important, but, on the other, not precisely defined. The concept and its development are traced in the writings of Daniel Stern, the person who introduced the concept into practice. Three periods of Stern's conceptual development are differentiated here, and an attempt is made to summarize them as certain basic types. By this means, it is shown that vitality affects are defined in relation to most areas of developmental psychology (the neuropsychological, the bodily, the conscious, and the interactional), and that the concept is thereby extended to so many areas that it tends toward disintegration. As final remarks, those qualities of the concept that we find most constructive, especially if one desires to approach the area empirically, are highlighted.     

Macaque monkeys discriminate pitch relationships

This study demonstrates that non-human primates can categorize the direction of the pitch change of tones in a sequence. Two Macaca fascicularis were trained in a positive-reinforcement behavioral paradigm in which they listened to sequences of a variable number of different acoustic items. The training of discriminating pitch direction was divided into three phases with increasing task complexity. In the first two phases, subjects learned to employ a same/different rule. In phase 1, they discriminated acoustic items of different sound quality. Subjects had to respond when there was a change from repeating noise bursts to repeating click trains or vice versa. In phase II, acoustic items differed along one physical dimension only. Subjects had to respond to a change of the frequency of a repeating series of pure tones. In phase III, sequences consisted of three series of repeating tones of different frequency. Subjects were required to respond when the frequency of the tones changed in a downward direction and to refrain from responding when the frequency remained constant or increased. After several ten thousand trials, subjects categorized pitch direction well above chance level. The discrimination was performed over a 4.5-octave range of frequencies and was largely independent of the temporal and ordinal position of the downward pitch direction within the sequence. These results demonstrate that monkeys can recognize pitch relationships and thus that monkeys have the concept of ordinal relations between acoustic items.     

错觉轮廓的适应效应

错觉轮廓反映知觉的主动建构过程, 考察其是否存在适应效应有助于理解视觉系统反馈调节的特性。我们采用Kanizsa这种典型的错觉轮廓来研究其适应过程, 结果发现：Kanizsa错觉轮廓具有适应效应, 并且这种适应主要是由主观形成的整体轮廓造成的, 而不是由Pac-Man上的线条引起的。表明依赖于高级视觉皮层反馈调节的主观建构过程和自下而上的神经元信息一样, 会随呈现时间的增加, 神经活动减弱, 体现为适应效应。     

A new conception of visual aesthetic sensitivity

Aesthetic sensitivity has been defined as the ability to recognize and appreciate beauty and compositional excellence, and to judge artistic merit according to standards of aesthetic value. The Visual Aesthetic Sensitivity Test (VAST) has often been used to assess this ability, but recent research has revealed it has several psychometric problems. Such problems are not easily remedied, because they reflect flawed assumptions inherent to the concept of aesthetic sensitivity as traditionally understood, and to the VAST itself. We introduce a new conception of aesthetic sensitivity defined as the extent to which someone's aesthetic valuation is influenced by a given feature. Experiment 1 aimed to characterize aesthetic sensitivity to four prominent features in visual aesthetics: complexity, symmetry, contour, and balance. Experiment 2 aimed to replicate the findings of Experiment 1 and to assess the test–retest reliability of an instrument designed to measure aesthetic sensitivity to these features using an abridged set of stimuli. Our results reveal that people differ remarkably in the extent to which visual features influence their liking, highlighting the crucial role of individual variation when modelling aesthetic preferences. We did not find clear relations between the four measures of aesthetic sensitivity and personality, intelligence, and art interest and knowledge. Finally, our measurement instrument exhibited an adequate-to-good test–retest reliability.     

关于轮廓与视觉搜索顺序的实验研究

轮廓是图形识别的重要线索,在平行加工形成轮廓的基础上,进一步的特征搜索会与轮廓有关。本研究通过3个实验探讨轮廓对于搜索顺序的作用。实验一的目的在于确认轮廓因素在视觉搜索中的关键作用,实验结果进一步验证了视觉搜索中存在“可能目标”的心理表征。实验二结果显示,图形的重叠虽然可以产生新的特征,但是未必提高搜索速度。由此引入关于轮廓与视觉搜索顺序的关系问题,提出了在轮廓形成的基础上搜索区别性特征的顺序为轮廓外区→轮廓本身→轮廓内区的假设。实验三进一步检验这个假设。