Independent perceptual reversals for simultaneously presented ambiguous figures

In two successive experiments using the divided visual field paradigm with vertical or horizontal division, two ambiguous figures, the Rubin’s vase-face or the Necker cube, were projected to the right and left or to the upper and lower visual hemifields of 108 healthy volunteers. Stimulation time was 120 s. The main hypotheses were (a) that different percepts of the same ambiguous figure may be simultaneously experienced in the two hemifields and (b) that the type (vertical vs. horizontal) of visual field division influences the reversal frequency and the temporal interdependence of the percepts.Results from the first experiment showed that the temporal interdependence of reversals was very low for both ambiguous figures, suggesting that during part of the stimulation time the subjects could experience different percepts of the same figure (e.g. a vase in the right and face profiles in the left visual hemifields). The second experiment showed that this perceptual dissociation occurred on average during one third of the stimulation time. In both experiments the type of visual field division did not influence either frequency or temporal interdependence of the reversals. When one single ambiguous figure was presented in the centre of the screen, the number of reversals was approximately the sum of the reversals observed with two figures presented simultaneously each in one hemifield.     

Ambiguous figure perception and theory of mind understanding in children with autistic spectrum disorders

Researchers in early social‐cognition have found that the ability to reverse an ambiguous figure is correlated with success on theory of mind tasks (e.g. Gopnik & Rosati, 2001 ). The present experiment examined children with autistic spectrum disorders (ASD) without mental delay to see whether a similar relationship existed. Ropar, Mitchell, and Ackroyd (2003) demonstrated that children with ASD with mental delay were impaired on theory of mind tasks, but were as likely as mentally delayed controls to generate both interpretations of an ambiguous figure when informed of its ambiguity. The present study replicated this finding on children with ASD without mental delay. However, overall perception of ambiguous figures was different. These children were less likely to spontaneously generate both interpretations of the figure, and more likely to perseverate on a single interpretation than the comparison children. Like Ropar et al., we found no correlation between theory of mind and informed reversals, but spontaneous reversals were correlated with performance on an advanced theory of mind task. These data suggest that reversals of ambiguous figures are linked to higher‐level representational abilities, which might also be involved in social functioning, and impaired in children with ASD.     

汉语发展性阅读障碍儿童的视知觉学习*

研究采用知觉学习经典范式中的视觉搜索任务探讨汉语发展性阅读障碍儿童的知觉学习过程。研究考察了阅读障碍儿童与正常儿童在简单搜索任务、复杂搜索任务和限制时间的复杂搜索任务上的知觉学习特点。结果发现,阅读障碍儿童在复杂搜索任务中初始搜索时间显著长于正常控制组;在限制时间的复杂搜索任务中更进一步发现阅读障碍儿童的反应正确率显著低于正常控制组儿童;而且两组儿童视觉搜索任务的正确率与汉语阅读的识字量成绩存在显著相关。上述结果表明,汉语发展性阅读障碍儿童存在复杂搜索的知觉学习缺陷,这种缺陷可能在某种程度上与儿童的阅读技能发展有关。     

Context effects on emotional and aesthetic evaluations of artworks and IAPS pictures

In the arts emotionally negative objects sometimes can be positively judged. Defining an object as art possibly yields specific changes in how perceivers emotionally experience and aesthetically judge a stimulus. To study how emotional experiences (joy, anger, disgust, fear, sadness, and shame ratings, plus facial EMG) and aesthetic judgements (liking ratings) are modulated by an art context (“This is an artwork”) as compared to non-art reality context (“This is a press photograph”) participants evaluated IAPS pictures and veridical artworks depicting emotionally positive and negative content. In line with the assumption that emotional distancing is an essential feature of the art experience we found that positive emotional reactions were attenuated (joy, M. zygomaticus activation) in an art compared to non-art context. However, context had little influence on negative emotional reactions (anger, disgust, fear, sadness, shame, and M. corrugator activation) suggesting that these are similar in art and non-art. Importantly, only artworks of emotionally negative content were judged more positively in an art context — thus liked more. This study, in accordance with the assumption of a distanced aesthetic mode, shows that an art context fosters appraisal processes that influence emotional experiences, allowing to judge negative stimuli aesthetically more positively — thus suppressing the immediacy of emotional stimulus content.     

The effect of touch on a visually ambiguous three-dimensional figure

The effect of haptic (i.e. tactile-kinaesthetic) information on the perception of an ambiguous visual figure was investigated. The figure used was a self-luminous, threedimensional wire cube viewed in darkness. It was found that visual reversals still took place when the cube was explored with the hands, but the reversal rate was reduced and the time increased during which the cube looked as it “really” was.     

Visual mental images can be ambiguous: insights from individual differences in spatial transformation abilities

The debate about whether objects in mental images can be ambiguous has produced ambiguous results. In some studies, participants could not reinterpret objects in images, but even in the studies where participants could reinterpret visualized patterns, the results are not conclusive. The present study used a novel task to investigate the reinterpretation of ambiguous figures in imagery, which required the participants to mentally rotate a figure 180 degrees before attempting to "see" an alternate interpretation. In addition, the participants did not know the purpose of the study in advance, nor did they see alternate interpretations of the stimuli; moreover, we explicitly measured individual differences in key mental imagery abilities. Eight of the 44 participants discovered the alternate version while they were memorizing the figure; 16 reported it after mentally rotating an image; and 20 were not able to "see" the alternate version. The ability to rotate images, assessed with an independent task, was highly associated with reports of image reversals, whereas measures of other imagery abilities were not.     

Individual differences in the acquisition of non‐linguistic audio‐visual associations in 5 year olds

Audio‐visual associative learning – at least when linguistic stimuli are employed – is known to rely on core linguistic skills such as phonological awareness. Here we ask whether this would also be the case in a task that does not manipulate linguistic information. Another question of interest is whether executive skills, often found to support learning, may play a larger role in a non‐linguistic audio‐visual associative task compared to a linguistic one. We present a new task that measures learning when having to associate non‐linguistic auditory signals with novel visual shapes. Importantly, our novel task shares with linguistic processes such as reading acquisition the need to associate sounds with arbitrary shapes. Yet, rather than phonemes or syllables, it uses novel environmental sounds – therefore limiting direct reliance on linguistic abilities. Five‐year‐old French‐speaking children (N = 76, 39 girls) were assessed individually in our novel audio‐visual associative task, as well as in a number of other cognitive tasks evaluating linguistic abilities and executive functions. We found phonological awareness and language comprehension to be related to scores in the audio‐visual associative task, while no correlation with executive functions was observed. These results underscore a key relation between foundational language competencies and audio‐visual associative learning, even in the absence of linguistic input in the associative task.     

Multistable phenomena: changing views in perception

Traditional explanations of multistable visual phenomena (e.g. ambiguous figures, perceptual rivalry) suggest that the basis for spontaneous reversals in perception lies in antagonistic connectivity within the visual system. In this review, we suggest an alternative, albeit speculative, explanation for visual multistability – that spontaneous alternations reflect responses to active, programmed events initiated by brain areas that integrate sensory and non-sensory information to coordinate a diversity of behaviors. Much evidence suggests that perceptual reversals are themselves more closely related to the expression of a behavior than to passive sensory responses: (1) they are initiated spontaneously, often voluntarily, and are influenced by subjective variables such as attention and mood; (2) the alternation process is greatly facilitated with practice and compromised by lesions in non-visual cortical areas; (3) the alternation process has temporal dynamics similar to those of spontaneously initiated behaviors; (4) functional imaging reveals that brain areas associated with a variety of cognitive behaviors are specifically activated when vision becomes unstable. In this scheme, reorganizations of activity throughout the visual cortex, concurrent with perceptual reversals, are initiated by higher, largely non-sensory brain centers. Such direct intervention in the processing of the sensory input by brain structures associated with planning and motor programming might serve an important role in perceptual organization, particularly in aspects related to selective attention.     

The Effect of Age on Rule-Based Category Learning

ABSTRACT

An explicit, rule-based, category-learning task with abstract visual stimuli was administered to 50 healthy older adults and 48 younger adults. Accuracy and reaction time (RT) were examined for the effects of age, perceptual abilities, rule memory, rule complexity, stimulus novelty, and response competition. Older adults performed at equivalent levels to younger adults when applying a simple rule, but showed performance decrements when applying a more complex rule. The age effect interacted with both stimulus novelty and response competition, and was not eliminated after controlling for basic perceptual abilities and rule memory. The authors suggest that older adults show category learning deficits in conditions that require enhanced cognitive control. These results are discussed in reference to the growing body of literature regarding age-related change in executive abilities and frontal lobe function.     

中国画审美一致性的专业知识效应:一项fNIRS研究

摘 要 本研究结合fNIRS技术,考察了美术训练学生和普通学生在中国画审美一致性上的差异。行为上,虽然两组被试在审美评分上没有显著差异,但在评分一致性上,美术训练学生相比普通学生在“好看”评分上更一致。脑活动上,美术训练学生右侧颞顶联合区的16通道和24通道的神经活动一致性显著高于普通学生,且美术训练学生的神经活动一致性与“好看”评分呈负相关。本研究揭示了艺术专业知识对中国画审美的重要性,且神经活动一致性可作为中国画审美判断的一项潜在神经标记。     

Illusions of integration are subjectively impenetrable: Phenomenological experience of Lag 1 percepts during dual-target RSVP

We investigated the relationship between different kinds of target reports in a rapid serial visual presentation task, and their associated perceptual experience. Participants reported the identity of two targets embedded in a stream of stimuli and their associated subjective visibility. In our task, target stimuli could be combined together to form more complex ones, thus allowing participants to report temporally integrated percepts. We found that integrated percepts were associated with high subjective visibility scores, whereas reports in which the order of targets was reversed led to a poorer perceptual experience. We also found a reciprocal relationship between the chance of the second target not being reported correctly and the perceptual experience associated with the first one. Principally, our results indicate that integrated percepts are experienced as a unique, clear perceptual event, whereas order reversals are experienced as confused, similar to cases in which an entirely wrong response was given.     

Multistable perception: when bottom-up and top-down coincide

During prolonged observation of an ambiguous figure sudden perceptual reversals occur, while the stimulus itself stays unchanged. There is a vivid debate about whether bottom-up or top-down mechanisms underlie this phenomenon. In the present study, we investigated the interrelation of two experimental factors: volitional control and discontinuous stimulus presentation. Both factors strongly modulate the rate of perceptual reversals and each is attributed either as top-down or bottom-up. We found that participants can apply specific strategies to volitionally increase and/or decrease the stability duration of each of the possible percepts according to the experimental instructions. When attempts of volitional control are combined with discontinuous stimulus presentation the effects are fully additive. Our results indicate that perceptual reversals can originate from different neural mechanisms on different time scales.     

Medial prefrontal cortex is selectively involved in response selection using visual context in the background

The exact roles of the medial prefrontal cortex (mPFC) in conditional choice behavior are unknown and a visual contextual response selection task was used for examining the issue. Inactivation of the mPFC severely disrupted performance in the task. mPFC inactivations, however, did not disrupt the capability of perceptual discrimination for visual stimuli. Normal response selection was also observed when nonvisual cues were used as conditional stimuli. The results strongly suggest that the mPFC is not necessarily involved in the inhibition of response or flexible response selection in general, but is rather critical when response selection is required conditionally using visual context in the background.     

执行功能与数量加工：回顾与展望

回顾了执行功能与数量加工之间的复杂关系。其中,执行功能的4个子系统——抑制、转换、刷新和双任务协调对数量加工的影响各不相同：抑制可以在一定程度上改变数量加工时的自动激活程度;转换功能则主要依赖注意来进行调节;刷新与数量加工关系的研究成果比较少;而双任务协调与数量加工之间的联系存在争论。文章最后分3个方面进行了研究趋势的展望,认为未来执行功能与数量加工的研究将突破相关研究的局限,通过更精巧的设计和大量特殊被试的研究取得突破性进展。     

The effect of age on rule-based category learning

An explicit, rule-based, category-learning task with abstract visual stimuli was administered to 50 healthy older adults and 48 younger adults. Accuracy and reaction time (RT) were examined for the effects of age, perceptual abilities, rule memory, rule complexity, stimulus novelty, and response competition. Older adults performed at equivalent levels to younger adults when applying a simple rule, but showed performance decrements when applying a more complex rule. The age effect interacted with both stimulus novelty and response competition, and was not eliminated after controlling for basic perceptual abilities and rule memory. The authors suggest that older adults show category learning deficits in conditions that require enhanced cognitive control. These results are discussed in reference to the growing body of literature regarding age-related change in executive abilities and frontal lobe function.     

Children's understanding of ambiguous figures: Which cognitive developments are necessary to experience reversal?

In two experiments involving one hundred and thirty-eight 3- to 5-year-olds we examined the claim that a complex understanding of ambiguity is required to experience reversal of ambiguous stimuli [Gopnik, A., & Rosati, A. (2001). Duck or rabbit? Reversing ambiguous figures and understanding ambiguous representations. Developmental Science, 4, 175–183]. In Experiment 1 a novel Production task measured the ability to acknowledge both interpretations of ambiguous figures. This was as easy as and significantly correlated with a False Belief task, and easier than a Droodle task. We replicated this finding in Experiment 2, and also found that perceiving reversal of ambiguous figures was harder than either the False Belief or Production tasks. In contrast to previous findings, the Reversal and Droodle tasks were not specifically related. We conclude that children only attempt reversal once they can understand the representational relationship between the figure and its two interpretations. The process resulting in reversal however is hard, probably requiring additional developments in executive functioning and imagery abilities.     

A dot that went for a walk: People prefer lines drawn with human-like kinematics

A dominant theory of embodied aesthetic experience (Freedberg & Gallese, 2007, Trends in Cognitive Sciences, 11, 197) posits that the appreciation of visual art is linked to the artist’s movements when creating the artwork, yet a direct link between the kinematics of drawing actions and the aesthetics of drawing outcomes has not been experimentally demonstrated. Across four experiments, we measured aesthetic responses of students from arts and non-arts backgrounds to drawing movements generated from computational models of human writing. Experiment 1 demonstrated that human-like drawing movements with bell-shaped velocity profiles (Sigma Lognormal [SL] and Minimum Jerk [MJ]) are perceived as more natural and pleasant than movements with a uniform profile, and in both Experiments 1 and 2 movements that were perceived as more natural were also preferred. Experiment 3 showed that this effect persists if lower-level dynamic stimulus features are fully matched across experimental and control conditions. Furthermore, aesthetic preference for human-like movements were associated with greater perceptual fluency in Experiment 3, evidenced by unbiased estimations of the duration of natural movements. In Experiment 4, line drawings with visual features consistent with the dynamics of natural, human-like movements were preferred, but only by art students. Our findings directly link the aesthetics of human action to the visual aesthetics of drawings, but highlight the importance of incorporating artistic expertise into embodied accounts of aesthetic experience.     

Visual Perception in Japanese Rock Garden Design

We present an investigation into the relation between design principles in Japanese gardens, and their associated perceptual effects. This leads to the realization that a set of design principles described in a Japanese gardening text by Shingen (1466), shows many parallels to the visual effects of perceptual grouping, studied by the Gestalt school of psychology. Guidelines for composition of rock clusters closely relate to perception of visual figure. Garden design elements are arranged into patterns that simplify figure-ground segmentation, while seemingly balancing the visual salience of subparts and the global arrangement. Visual ‘ground’ is analyzed via medial axis transformation (MAT), often associated with shape perception in humans. MAT analysis reveals implicit structure in the visual ground of a quintessential rock garden design. The MAT structure enables formal comparison of structure of figure and ground. They share some aesthetic qualities, with interesting differences. Both contain naturalistic asymmetric, self-similar, branching structures. While the branching pattern of the ground converges towards the viewer, that of the figure converges in the opposite direction.     

Competition effects of threatening faces in social anxiety

Threatening faces involuntarily grab attention in socially anxious individuals. It is unclear, however, whether attention capture is at the expense of concurrent visual processing. The current study examined the perceptual cost effects of viewing fear-relevant stimuli (threatening faces) relative to a concurrent change-detection task. Steady-state visual evoked potentials (ssVEPs) were used to separate the neural response to 2 fully overlapping types of stimuli flickering at different frequencies: Task-irrelevant facial expressions (angry, neutral, happy) were overlaid with a task-relevant Gabor patch stream, which required a response to rare phase reversals. Groups of 17 high and 17 low socially anxious observers were recruited through online prescreening of 849 students. A prominent competition effect of threatening faces was observed solely in elevated social anxiety: When an angry face, relative to a neutral or happy face, served as a distractor, heightened ssVEP amplitudes were seen at the tagging frequency of that facial expression. Simultaneously, the ssVEP evoked by the task-relevant Gabor grating was reliably diminished compared with conditions with neutral or happy distractor faces. Thus, threatening faces capture and hold low-level perceptual resources in viewers symptomatic for social anxiety at the cost of a concurrent primary task. It is important to note that this competition in lower tier visual cortex was maintained throughout the viewing period and was unaccompanied by competition effects on behavioral performance. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

自我相关信息对视觉搜索主动抑制的易化作用

工作记忆表征会以自上而下的方式调控注意选择过程, 其中一种表现就是能够对储存的干扰物表征产生注意的主动抑制, 进而提高对目标的搜索效率。另一方面, 凸显性刺激也会以自下而上的方式优先捕获注意。那么, 当保持在工作记忆中的干扰物为更具社会凸显性特征的刺激(如与自己有关的信息)时, 会对视觉搜索过程中的注意抑制产生怎样的影响, 目前尚不清楚。本研究采用短暂联结任务和工作记忆引导的视觉搜索任务范式, 探讨了自我凸显性对注意主动抑制的影响。结果发现, 相比他人和中性条件, 当工作记忆表征为自我联结刺激时, 目标搜索反应更快。本研究从行为层面为自我相关信息能够易化主动抑制过程提供了证据。