Perceived slant has often been characterized as a component of 3D shape perception for polyhedral objects. Like 3D shape, slant is often perceived inaccurately. Lind, Lee, Mazanowski, Kountouriotis, ...and Bingham (2014) found that 3D shape was perceived accurately with perspective changes ≥45°. We now similarly tested perception of 3D slant. To account for their results, Lind et al. (2014) developed a bootstrap model based on the assumption that optical information yields perception of 3D relief structure then used with large perspective changes to bootstrap to perception of 3D Euclidean structure. However, slant perception usually entails planar surfaces and structure-from-motion fails in the absence of noncoplanar points. Nevertheless, the displays in Lind et al. (2014) included stereomotion in addition to monocular optical flow. Because stereomotion is higher order, the bootstrap model might apply in the case of strictly planar surfaces. We investigated whether stereomotion, monocular structure-from-motion (SFM), or the combination of the two would yield accurate 3D slant perception with large continuous perspective change. In Experiment 1, we found that judgments of slant were inaccurate in all information conditions. In Experiment 2, we added noncoplanar structure to the surfaces. We found that judgments in the monocular SFM and combined conditions now became correct once perspective changes were ≥45°, replicating the results of Lind et al. (2014) and supporting the bootstrap model. In short, we found that noncoplanar structure was required to enable accurate perception of 3D slant with sufficiently large perspective changes.
Public Significance Statement
A majority of the studies on slant perception as well as perception of other spatial properties, like shape, have shown perception is inaccurate. This is a problem for the control of actions that are not continuously guided by vision. In this study, we investigated visual information generated by motion, and showed that with sufficiently large continuous perspective change, surface orientation was perceived accurately. Such perspective changes would be generated by the locomotion of observers in everyday environments. This result not only provided additional confirmation for a model developed in a previous study on accurate shape perception, but also showed that the 3D structure of natural environments is important for perception of surface orientations.
In the first comprehensive study of the relationship between music and language from the standpoint of cognitive neuroscience, Aniruddh D. Patel challenges the widespread belief that music and ...language are processed independently. This volume argues that music and language share deep and critical connections, and that comparative research provides a powerful way to study the cognitive and neural mechanisms underlying these uniquely human abilities.
In 1996, the Los Angeles Bus Riders Union, a grassroots advocacy organization, won a historic legal victory against the citys Metropolitan Transit Authority. The resulting consent decree forced the ...MTA for a period of ten years to essentially reorient the mass transit system to better serve the citys poorest residents. A stunning reversal of conventional governance and planning in urban America, which almost always favors wealthier residents, this decision is also, for renowned urban theorist Edward W. Soja, a concrete example of spatial justice in action.In Seeking Spatial Justice , Soja argues that justice has a geography and that the equitable distribution of resources, services, and access is a basic human right. Building on current concerns in critical geography and the new spatial consciousness, Soja interweaves theory and practice, offering new ways of understanding and changing the unjust geographies in which we live. After tracing the evolution of spatial justice and the closely related notion of the right to the city in the influential work of Henri Lefebvre, David Harvey, and others, he demonstrates how these ideas are now being applied through a series of case studies in Los Angeles, the city at the forefront of this movement. Soja focuses on such innovative laborcommunity coalitions as Justice for Janitors, the Los Angeles Alliance for a New Economy, and the Right to the City Alliance; on struggles for rent control and environmental justice; and on the role that faculty and students in the UCLA Department of Urban Planning have played in both developing the theory of spatial justice and putting it into practice.Effectively locating spatial justice as a theoretical concept, a mode of empirical analysis, and a strategy for social and political action, this book makes a significant contribution to the contemporary debates about
justice, space, and the city.
Speech is robustly audiovisual from early in infancy. Here we show that audiovisual speech perception in 4.5-month-old infants is influenced by sensorimotor information related to the lip movements ...they make while chewing or sucking. Experiment 1 consisted of a classic audiovisual matching procedure, in which two simultaneously displayed talking faces (visual i and u) were presented with a synchronous vowel sound (audio /i/ or /u/). Infants' looking patterns were selectively biased away from the audiovisual matching face when the infants were producing lip movements similar to those needed to produce the heard vowel. Infants' looking patterns returned to those of a baseline condition (no lip movements, looking longer at the audiovisual matching face) when they were producing lip movements that did not match the heard vowel. Experiment 2 confirmed that these sensorimotor effects interacted with the heard vowel, as looking patterns differed when infants produced these same lip movements while seeing and hearing a talking face producing an unrelated vowel (audio /a/). These findings suggest that the development of speech perception and speech production may be mutually informative.
Human multisensory systems are known to bind inputs from the different sensory modalities into a unified percept, a process that leads to measurable behavioral benefits. This integrative process can ...be observed through multisensory illusions, including the McGurk effect and the sound-induced flash illusion, both of which demonstrate the ability of one sensory modality to modulate perception in a second modality. Such multisensory integration is highly dependent upon the temporal relationship of the different sensory inputs, with perceptual binding occurring within a limited range of asynchronies known as the temporal binding window (TBW). Previous studies have shown that this window is highly variable across individuals, but it is unclear how these variations in the TBW relate to an individual's ability to integrate multisensory cues. Here we provide evidence linking individual differences in multisensory temporal processes to differences in the individual's audiovisual integration of illusory stimuli. Our data provide strong evidence that the temporal processing of multiple sensory signals and the merging of multiple signals into a single, unified perception, are highly related. Specifically, the width of right side of an individuals' TBW, where the auditory stimulus follows the visual, is significantly correlated with the strength of illusory percepts, as indexed via both an increase in the strength of binding synchronous sensory signals and in an improvement in correctly dissociating asynchronous signals. These findings are discussed in terms of their possible neurobiological basis, relevance to the development of sensory integration, and possible importance for clinical conditions in which there is growing evidence that multisensory integration is compromised.
In 1912, Max Wertheimer published his paper on phi motion, widely recognized as the start of Gestalt psychology. Because of its continued relevance in modern psychology, this centennial anniversary ...is an excellent opportunity to take stock of what Gestalt psychology has offered and how it has changed since its inception. We first introduce the key findings and ideas in the Berlin school of Gestalt psychology, and then briefly sketch its development, rise, and fall. Next, we discuss its empirical and conceptual problems, and indicate how they are addressed in contemporary research on perceptual grouping and figure-ground organization. In particular, we review the principles of grouping, both classical (e.g., proximity, similarity, common fate, good continuation, closure, symmetry, parallelism) and new (e.g., synchrony, common region, element and uniform connectedness), and their role in contour integration and completion. We then review classic and new image-based principles of figure-ground organization, how it is influenced by past experience and attention, and how it relates to shape and depth perception. After an integrated review of the neural mechanisms involved in contour grouping, border ownership, and figure-ground perception, we conclude by evaluating what modern vision science has offered compared to traditional Gestalt psychology, whether we can speak of a Gestalt revival, and where the remaining limitations and challenges lie. A better integration of this research tradition with the rest of vision science requires further progress regarding the conceptual and theoretical foundations of the Gestalt approach, which is the focus of a second review article. (Contains 24 figures and 6 tables.)
What factors constrain whether tool use modulates the user's body representations? To date, studies on representational plasticity following tool use have primarily focused on the act of using the ...tool. Here, we investigated whether the tool's morphology also serves to constrain plasticity. In 2 experiments, we varied whether the tool was morphologically similar to a target body part (Experiment 1, hand; Experiment 2, arm). Participants judged the tactile distance between pairs of points applied to their tool-using target body surface and forehead (control surface) before and after tool use. We applied touch in 2 orientations, allowing us to quantify how tool use modulates the representation's shape. Significant representational plasticity in hand shape (increase in width, decrease in length) was found when the tool was morphologically similar to a hand (Experiment 1A), but not when the tool was arm-shaped (Experiment 1B). Conversely, significant representational plasticity was found on the arm when the tool was arm-shaped (Experiment 2B), but not when hand-shaped (Experiment 2A). Taken together, our results indicate that morphological similarity between the tool and the effector constrains tool-induced representational plasticity. The embodiment of tools may thus depend on a match-to-template process between tool morphology and representation of the body.
Despite decades of research, little is known about how people visually perceive object shape. We hypothesize that a promising approach to shape perception is provided by a "visual perception as ...Bayesian inference" framework which augments an emphasis on visual representation with an emphasis on the idea that shape perception is a form of statistical inference. Our hypothesis claims that shape perception of unfamiliar objects can be characterized as statistical inference of 3D shape in an object-centered coordinate system. We describe a computational model based on our theoretical framework, and provide evidence for the model along two lines. First, we show that, counterintuitively, the model accounts for viewpoint-dependency of object recognition, traditionally regarded as evidence against people's use of 3D object-centered shape representations. Second, we report the results of an experiment using a shape similarity task, and present an extensive evaluation of existing models' abilities to account for the experimental data. We find that our shape inference model captures subjects' behaviors better than competing models. Taken as a whole, our experimental and computational results illustrate the promise of our approach and suggest that people's shape representations of unfamiliar objects are probabilistic, 3D, and object-centered.
The research is devoted to the study of the actualization of meanings in a literary text. The study is based on the material of a medieval novel. The subject of the study was the corpus of texts of ...chivalric novels. In the aggregate, the study of (linguistic-rhetorical) works. The analysis was carried out from the position of studying the author's strategy of influencing the reader in order to have a certain attitude to the hero or plot of the work. The author's influencing strategy in novels is conceptually different from the strategies in works of other genres. The fact that in the works of different authors, united by one image of the main character, use similar elements of influence on the reader, which indicates a special perception of the image of the main character in the minds of people of the XII–XV centuries. This perception is formed both from the totality of literary techniques that pass from work to work, and at the level of linguistic means.
The action-specific perception account holds that people perceive the environment in terms of their ability to act in it. In this view, for example, decreased ability to climb a hill because of ...fatigue makes the hill visually appear to be steeper. Though influential, this account has not been universally accepted, and in fact a heated controversy has emerged. The opposing view holds that action capability has little or no influence on perception. Heretofore, the debate has been quite polarized, with efforts largely being focused on supporting one view and dismantling the other. We argue here that polarized debate can impede scientific progress and that the search for similarities between 2 sides of a debate can sharpen the theoretical focus of both sides and illuminate important avenues for future research. In this article, we present a synthetic review of this debate, drawing from the literatures of both approaches, to clarify both the surprising similarities and the core differences between them. We critically evaluate existing evidence, discuss possible mechanisms of action-specific effects, and make recommendations for future research. A primary focus of future work will involve not only the development of methods that guard against action-specific postperceptual effects but also development of concrete, well-constrained underlying mechanisms. The criteria for what constitutes acceptable control of postperceptual effects and what constitutes an appropriately specific mechanism vary between approaches, and bridging this gap is a central challenge for future research.
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