This paper argues that a common form of representationalism has trouble accommodating empirical findings about visual space perception. Vision science tells us that the visual system systematically gives rise to different experiences of the same spatial property. This, combined with a naturalistic account of content, suggests that the same spatial property can have different veridical looks. I use this to argue that a common form of representationalism about spatial experience must be rejected. I conclude by considering (...) alternatives to this view. (shrink)

In the philosophy of perception, direct realism has come into vogue. Philosophical authors assert and assume that what their readers want, and what anyone should want, is some form of direct realism. There are disagreements over precisely what form this direct realism should take. The majority of positions in favor now offer a direct realism in which objects and their material or physical properties constitute the contents of perception, either because we have an immediate or intuitive acquaintance with (...) those objects and properties, or because our perceptual states have informational content that represents the properties of those objects (and which is not itself an object of perception and has no specifically subjective aspect). This paper considers various forms of perceptual realism, including, for purposes of comparison, the largely abandoned indirect or representative realism. After surveying the variety of perceptual realisms and considering their various commitments, I introduce some considerations concerning the phenomenology of visual space that cause trouble for most forms of direct realism. These considerations pertain to the perception of objects in the distance and, secondarily, to the perception of shapes at a slant. I argue that one of the lesser known varieties of perceptual realism, critical direct realism, can meet the challenges offered by the facts of spatial perception. (shrink)

Some recently popular accounts of perception account for the phenomenal character of perceptual experience in terms of the qualities of objects. My concern in this paper is with naturalistic versions of such a phenomenal externalist view. Focusing on visual spatial perception, I argue that naturalistic phenomenal externalism conflicts with a number of scientific facts about the geometrical characteristics of visual spatial experience.

Kant, Wittgenstein, and Husserl all held that visual awareness of objects requires visual awareness of the space in which the objects are located. There is a lively debate in the literature on spatial perception whether this view is undermined by the results of experiments on a Balint’s syndrome patient, known as RM. I argue that neither of two recent interpretations of these results is able to explain RM’s apparent ability to experience motion. I outline some ways (...) in which each interpretation may respond to this challenge, and suggest which way of meeting the challenge is preferable. I conclude that RM retains some awareness of the larger space surrounding the objects he sees. (shrink)

Visual space can be distinguished from physical space. The first is found in visual experience, while the second is defined independently of perception. Theorists have wondered about the relation between the two. Some investigators have concluded that visual space is non-Euclidean, and that it does not have a single metric structure. Here it is argued that visual space exhibits contraction in all three dimensions with increasing distance from the observer, that experienced (...) features of this contraction are not the same as would be the experience of a perspective projection onto a fronto-parallel plane, and that such contraction is consistent with size constancy. These properties of visual space are different from those that would be predicted if spatial perception resulted from the successful solution of the inverse problem. They are consistent with the notion that optical constraints have been internalized. More generally, they are also consistent with the notion that visual spatial structures bear a resemblance relation to physical spatial structures. This notion supports a type of representational relation that is distinct from mere causal correspondence. The reticence of some philosophers and psychologists to discuss the structure of phenomenal space is diagnosed in terms of the simple materialism and the functionalism of the 1970s and 1980s. (shrink)

Cognitive impenetrability (CI) of a large part of visual perception is taken for granted by those of us in the field of computational vision who attempt to recover descriptions of space using geometry and statistics as tools. These tools clearly point out, however, that CI cannot extend to the level of structured descriptions of object surfaces, as Pylyshyn suggests. The reason is that visual space – the description of the world inside our heads – is (...) a nonEuclidean curved space. As a consequence, the only alternative for a vision system is to develop several descriptions of space–time; these are representations of reduced intricacy and capture partial aspects of objective reality. As such, they make sense in the context of a class of tasks/actions/plans/purposes, and thus cannot be cognitively impenetrable. (shrink)

The two contrasting theoretical approaches to visual perception, the constructivist and the ecological, are briefly presented and illustrated through their analyses of space and size perception. Earlier calls for their reconciliation and unification are reviewed. Neurophysiological, neuropsychological, and psychophysical evidence for the existence of two quite distinct visual systems, the ventral and the dorsal, is presented. These two perceptual systems differ in their functions; the ventral system's central function is that of identification, while the dorsal (...) system is mainly engaged in the visual control of motor behavior. The strong parallels between the ecological approach and the functioning of the dorsal system, and between the constructivist approach and the functioning of the ventral system are noted. It is also shown that the experimental paradigms used by the proponents of these two approaches match the functions of the respective visual systems. A dual-process approach to visual perception emerges from this analysis, with the ecological-dorsal process transpiring mainly without conscious awareness, while the constructivist-ventral process is normally conscious. Some implications of this dual-process approach to visual-perceptual phenomena are presented, with emphasis on space perception. Key Words: constructivist; dual-process approach; ecological; size perception; space perception; two visual systems; visual perception theories. (shrink)

A meta-analysis and an experiment show that the degree of compression of the in-depth dimension of visual space relative to the frontal dimension increases quickly as a function of the distance between the stimulus and the observer at first, but the rate of change slows beyond 7 m from the observer, reaching an apparent asymptote of about 50 %. In addition, the compression of visual space is greater for monocular and reduced cue conditions. The pattern of (...) compression of the in-depth dimension as a function of distance is similar to the ratio of in-depth to frontal visual angles of stimuli, but is not as extreme as this ratio would suggest, implying that observers are incapable of fully ignoring size information provided by cues to depth. Size and distance judgments may be described by an Affine transformation of physical space; however, the compression parameter in this model changes as a function of distance from the observer and other experimental conditions. (shrink)

In spatial sequence synaesthesia ordinal stimuli are perceived as arranged in peripersonal space. Using fMRI, we examined the neural bases of SSS and colour synaesthesia for spoken words in a late-blind synaesthete, JF. He reported days of the week and months of the year as both coloured and spatially ordered in peripersonal space; parts of the days and festivities of the year were spatially ordered but uncoloured. Words that denote time-units and triggered no concurrents were used in a (...) control condition. Both conditions inducing SSS activated the occipito-parietal, infero-frontal and insular cortex. The colour area hOC4v was engaged when the synaesthetic experience included colour. These results confirm the continued recruitment of visual colour cortex in this late-blind synaesthetes. Synaesthesia also involved activation in inferior frontal cortex, which may be related to spatial memory and detection, and in the insula, which might contribute to audiovisual integration related to the processing of inducers and concurrents. (shrink)

A period of exposure to trains of simultaneous but spatially offset auditory and visual stimuli can induce a temporary shift in the perception of sound location. This phenomenon, known as the 'ventriloquist aftereffect', reflects a realignment of auditory and visual spatial representations such that they approach perceptual alignment despite their physical spatial discordance. Such dynamic changes to sensory representations are likely to underlie the brain's ability to accommodate inter-sensory discordance produced by sensory errors (particularly in sound localization) (...) and variability in sensory transduction. It is currently unknown, however, whether these plastic changes induced by adaptation to spatially disparate inputs occurs automatically or whether they are dependent on selectively attending to the visual or auditory stimuli. Here, we demonstrate that robust auditory spatial aftereffects can be induced even in the presence of a competing visual stimulus. Importantly, we found that when attention is directed to the competing stimuli, the pattern of aftereffects is altered. These results indicate that attention can modulate the ventriloquist aftereffect. © 2010 Elsevier B.V. (shrink)

Maurice Merleau-Ponty argued that the seeing of things together (focal figure and background objects) accounted for the sense that things possess unseen depth: they are three-dimensional entities, not facades. I compare this idea to the law of large numbers. In both cases, single entities take on substance, depth, or meaning when assimilated into a large body of comparable instances. Thinking along these lines, Erwin Schrödinger proposed that living processes achieve order by virtue of the multiplicity of their constituent parts, any (...) of which, when considered individually, militate against perception and understanding. He further suggested that those parts take their place as things to be perceived even as they constitute our perceiving faculties, and this is why uncertainty occasions their reality. Thus he offers an instance of Merleau-Ponty’s notion of chiasmic intertwining, which allows for world-body interchange or reversibility beyond the reach of unequivocal apprehension. (shrink)

Maurice Merleau-Ponty argued that the seeing of things together (focal figure and background objects) accounted for the sense that things possess unseen depth: they are three-dimensional entities, not facades. I compare this idea to the law of large numbers. In both cases, single entities take on substance, depth, or meaning when assimilated into a large body of comparable instances. Thinking along these lines, Erwin Schrödinger proposed that living processes achieve order by virtue of the multiplicity of their constituent parts, any (...) of which, when considered individually, militate against perception and understanding. He further suggested that those parts take their place as things to be perceived even as they constitute our perceiving faculties, and this is why uncertainty occasions their reality. Thus he offers an instance of Merleau-Ponty’s notion of chiasmic intertwining, which allows for world-body interchange or reversibility beyond the reach of unequivocal apprehension. (shrink)

Visual Perception of Shape, Space and Appearance Liliana Albertazzi. the sort I have in mind. What I am speaking of is the mandatory correlations between attributes of visual space (those of, e.g., surfaces, shape, distance, direction) and  ...

This paper examines Berkeley's attitude toward our perception of spatial relations on the two- dimensional visual field. This is a topic on which there has been some controversy. Historians of visual theory have tended to suppose that Berkeley took "all" spatial relations to be derived in the way our knowledge of depth is: from association of more primitive sensations which are themselves in no way spatial. But many philosophers commenting on Berkeley have supposed that he takes our (...) awareness of two- dimensional visual layout to be directly perceived. I argue that Berkeley's position on this issue is deeply ambivalent and that neither alternative sits well with the rest of his philosophy. (shrink)

This project uses machine learning and computer vision techniques and a novel interactive visualization tool to provide street-level characterization of urban spaces such as safety and maintenance in urban neighborhoods. This is achieved by collecting and annotating street-view images, extracting objective metrics through computer vision techniques, and using crowdsourcing to statistically model the perception of subjective metrics such as safety and maintenance. For modeling human perception and scaling it up with a predictive algorithm, we evaluate perception predictions (...) across two points in time separated by economic changes in the urban core of Raleigh, North Carolina, in the aftermath of the 2008 Great Recession. We hypothesize specific socioeconomic processes can be substantially reflected in the built environment of cities and, thus, render themselves visible at the street level. This paper describes the process of incorporating subjective visual ratings across two datasets of temporally separated street-view images, an algorithm, and a visualization tool. This work serves as a case study for utilizing AI and visualization techniques in a richer characterization of urban spaces that includes both objective metrics such as income (that operates at a broader scale) and subjective metrics such as perception of individuals (that operates at a narrower scale at specific locations). We outline an interdisciplinary methodology to test this hypothesis in streetscape data from Raleigh, NC, from 2008 to 2020. We describe the results of training algorithms that utilized image features with crowdsourced human perception ratings. We provide a comparison of the results with income data. The analysis and interpretation of this comparison provide insight into the challenges and opportunities for using AI technology in characterizing changes in urban environments. One challenge is the ability of human domain experts to interpret the output of algorithms through manipulation and to integrate these results into their workflow. This is addressed with a novel interface designed for interactive analysis and visualization. We conclude with a discussion of some of the benefits and limitations of integrating AI models in the human expert’s decision-making process in the presence of both subjective and objective metrics. (shrink)

Many philosophers have held that it is not possible to experience a spatial object, property, or relation except against the background of an intact awareness of a space that is somehow ‘absolute’. This paper challenges that claim, by analyzing in detail the case of a brain-damaged subject whose visual experiences seem to have violated this condition: spatial objects and properties were present in his visual experience, but space itself was not. I go on to suggest that (...) phenomenological argumentation can give us a kind of evidence about the nature of the mind even if this evidence is not absolutely incorrigible. (shrink)

Although the “Transcendental Aesthetic” is the briefest part of the first Critique, it has garnered a lion's share of discussion. This fact reflects the important implications that Kant drew from his arguments there. He used the arguments concerning space and time to display examples of synthetic a priori cognition, to secure his division between intuitions and concepts, and to support transcendental idealism. Earlier, in the years around 1770, Kant's investigations into space and time had facilitated his turn toward (...) “critical” philosophy. Prior to that time, Kant's main interests in space and time pertained to physics and metaphysics. As he entered the critical period, he delved into the cognitive basis of our experience of space (and time), and drew his conclusions about their ideality. Kant's doctrines of space and time provoked extensive response in his own time and throughout the nineteenth century. These responses variously concerned the metaphysics, physics, epistemology, psychology, and geometry of space. Throughout the nineteenth century, philosophers, physiologists, and psychologists sought to extend or to refute Kant's theories of space. By the last decades of the nineteenth century, many had rightly concluded that the existence of non-Euclidean geometry as a candidate description of physical space refuted Kant's full doctrine of space - though some have hoped that his position might be saved by restricting it to “visual space.”. (shrink)

Visually impaired people have unique perceptions of and usage requirements for various urban spaces. Therefore, understanding these perceptions can help create reasonable layouts and construct urban infrastructure. This study recruited 26 visually impaired volunteers to evaluate 24 sound environments regarding clarity, comfort, safety, vitality, and depression. This data was collected in seven different types of urban spaces. An independent sample non-parametric test was used to determine the significance of the differences between environmental evaluation results for each evaluation dimension and to (...) summarize the compositions of sound and space elements in the positive and negative influence spaces. The results suggested that visually impaired people feel comfort, safety, and clarity in parks, residential communities, and shopping streets; have negative perceptions of vegetable markets, bus stops, hospitals, and urban departments; feel anxious when traffic sounds, horn sounds, manhole cover sounds, and construction sounds occur; and prefer spaces away from traffic, with fewer and slower vehicles, with a suitable space scale, and moderate crowd density. These results provide a reference for the future design of activity venues and the planning of accessibility systems for visually impaired urban residents. (shrink)

Color coding is used to guide attention in computer displays for such critical tasks as baggage screening or air traffic control. It has been shown that a display object attracts more attention if its color is more similar to the color for which one is searching. However, what does similar precisely mean? Can we predict the amount of attention that a display color will receive during a search for a given target color? To tackle this question, two color‐search experiments measuring (...) the selectivity of saccadic eye movements and mapping out its underlying color space were conducted. A variety of mathematical models, predicting saccadic selectivity for given target and display colors, were devised and evaluated. The results suggest that applying a Gaussian function to a weighted Euclidean distance in a slightly modified HSI color space is the best predictor of saccadic selectivity in the chosen paradigm. Hue and intensity information by itself provides a basis for useful predictors, spanning a possibly spherical color space of saccadic selectivity. Although the current models cannot predict saccadic selectivity values for a wide variety of visual search tasks, they reveal some characteristics of color search that are of both theoretical and applied interest, such as for the design of human–computer interfaces. (shrink)

Prior to the discovery of linear perspective in the fifteenth century, European artists based their compositions more on imagination than the direct observation of nature. Medieval paintings, therefore, can be thought of as ‘mental projections’ of space rather than optical projections, and were sometimes regarded as ‘primitive’ by historians as they lacked the spatial consistency of later works based on the rules of linear perspective. There are noticeable differences in the way objects are depicted in paintings of the different (...) periods. For example, human figures in pre-linear perspective works often vary greatly in size in ways that are not consistent with the laws of optics. Some art historians have attributed this to ‘hierarchical scaling’ in which larger figures have greater narrative significance. But there are examples of paintings that contradict this explanation. In this paper we will consider an alternative to the hierarchical scaling hypothesis: that medieval artists used relative size to elicit empathy and to reflect the perceptual structure of imagination. This hypothesis was first proposed by the art historian Oskar Wulff, but has largely been dismissed since. We argue that artists of this period, far from being naïve, used sophisticated techniques for directing the attention of the viewer to a particular figure in a painting and encouraging them to ‘see’ the depicted space from that figure’s point of view. We offer some experimental evidence in support of this hypothesis and suggest that the way artists have depicted space in paintings has an important bearing on how we imagine and perceive visual space. (shrink)

Ordinary human perceivers know that visual objects are perceivable from standpoints other than their own. The aim of this paper is to provide an explanation of how perceptual experience equips perceivers with this knowledge. I approach the task by discussing a variety of action-based theories of perception. Some of these theories maintain that standpoint transcendence is required for shape perception. I argue that this standpoint transcendence must take place in the phenomenal present and that it can be (...) explained in terms of the experience of perceivers who jointly attend to an object. Joint perceivers experience objects as being perceived from standpoints other than their own. They operate in what I call “social space”, in which they single out objects by triangulating targets’ locations relative to their co-perceivers’ standpoints on these targets. It is then possible to explain the public character of the objects of individual experience by appeal to what I call “public space”. This is a spatial framework whose locations are presented as standpoints whence joint attention to the target would ensue, were they occupied by co-perceivers. If shape perception requires standpoint transcendence, then shape perceivers operate in public space and are thus capable of singling out targets by triangulating their locations from standpoints other than their own. If it doesn’t, then the introduction of a public spatial framework is an additional step whose introduction explains how perceivers come to experience objects as perceivable from standpoints other than their own. (shrink)

Thomas Reid's Geometry of Visibles, according to which the geometrical properties of an object's perspectival appearance equal the geometrical properties of its projection on the inside of a sphere with the eye in its centre allows for two different interpretations. It may (1) be understood as a theory about phenomenal visual space – i.e. an account of how things appear to human observers from a certain point of view – or it may (2) be seen as a mathematical (...) model of viewpoint-relative but mind-independent relational properties of objects. This paper makes a systematic and a historical claim. I shall argue, first, that given certain features of the human visual system phenomenal visual space differs in several aspects from Reidean visual space. Secondly, I suggest that, since Reid was aware of some of these empirical facts, we should interpret Reid as endorsing the second interpretation of the Geometry of Visibles. (shrink)

Representation and content in some (actual) theories of perception -- Representation in perception and cognition : task analysis, psychological functions, and rule instantiation -- Perception as unconscious inference -- Representation and constraints : the inverse problem and the structure of visual space -- On perceptual constancy -- Getting objects for free (or not) : the philosophy and psychology of object perception -- Color perception and neural encoding : does metameric matching entail a loss (...) of information? -- Objectivity and subjectivity revisited : color as a psychobiological property -- Sense data and the mind body problem -- The reality of qualia -- The sensory core and the medieval foundations of early modern perceptual theory -- Postscript (2008) on Ibn al-Haytham's (Alhacen's) theory of vision -- Attention in early scientific psychology -- Psychology, philosophy, and cognitive science : reflections on the history and philosophy of experimental psychology -- What can the mind tell us about the brain? : psychology, neurophysiology, and constraint -- Introspective evidence in psychology. (shrink)

Global era is an era of acculturation which may surface difficulties due to the tendency of becoming global chaos that may influence people’s thought. Everyonehas their own views and has made changes with their own worldview perception; hybrid and heterodox. Changes without wisdom will eliminate local elements.This phenomenon has influenced myriad forms of visual composition and architecture of Bali Madya dwelling. Balinese culture has gone through various changes since Rsi Markandeya in the 9th century, Empu Kuturan in the (...) 10th century and Danghyang Nirartha in the 14th century. They changed many dwelling arrangements in architecture. Changes do not mean that one has to demolish the local indigenous elements but, instead, should attempt to develop various indigenous elements with the intention that the visual interior and architectural compositions have their own distinctive characters. In relation to that, aesthetic image and traditional space concept will be arranged in various kinds of acculturation in global visual forms. The dwelling space of Bali Madya concept was acculturated from the Bali Aga’s space concept during the era of Majapahit. This research is based on aesthetic and historical approach that stressed on the artistic aspects and design that are associated with aesthetic appeal. The analysis was done using observations of form and function including the meaning of space composition which was arranged to produce a proportionate composition with local images. (shrink)

Global era is an era of acculturation which may surface difficulties due to the tendency of becoming global chaos that may influence people’s thought. Everyonehas their own views and has made changes with their own worldview perception; hybrid and heterodox. Changes without wisdom will eliminate local elements.This phenomenon has influenced myriad forms of visual composition and architecture of Bali Madya dwelling. Balinese culture has gone through various changes since Rsi Markandeya in the 9th century, Empu Kuturan in the (...) 10th century and Danghyang Nirartha in the 14th century. They changed many dwelling arrangements in architecture. Changes do not mean that one has to demolish the local indigenous elements but, instead, should attempt to develop various indigenous elements with the intention that the visual interior and architectural compositions have their own distinctive characters. In relation to that, aesthetic image and traditional space concept will be arranged in various kinds of acculturation in global visual forms. The dwelling space of Bali Madya concept was acculturated from the Bali Aga’s space concept during the era of Majapahit. This research is based on aesthetic and historical approach that stressed on the artistic aspects and design that are associated with aesthetic appeal. The analysis was done using observations of form and function including the meaning of space composition which was arranged to produce a proportionate composition with local images. (shrink)

Facial information is a powerful channel for human-to-human communication. Characteristically, faces can be defined as biological objects that are four-dimensional (4D) patterns, whereby they have concurrently a spatial structure as well as temporal dynamics. The spatial characteristics of facial objects possess three dimensions (3D), namely breadth, height and importantly, depth. The temporal properties of facial objects are defined by how a 3D facial structure evolves dynamically over time; where time is referred to as the fourth dimension (4D). Our entire perspective (...) of another’s face, whether it be social, affective or cognitive perceptions, is therefore built on a combination of 3D and 4D visual cues. Counterintuitively, over the past few decades of experimental research in psychology, facial stimuli have largely been presented to participants as a spatial pattern that has been flattened into two dimensions (2D), while remaining largely static. The following review aims to advance and update facial researchers, on the recent revolution in computer-generated, realistic 4D facial models produced from real-life human subjects. We delve in-depth to summarize recent studies which have utilized facial stimuli that possess 3D structural cues (geometry and depth) and 4D temporal cues (3D structure + dynamic viewpoint and movement). In sum, we have found that higher-order perceptions such as identity, gender, ethnicity, emotion and personality, are critically influenced by the 4D characteristics embedded within natural human faces. In future, it is recommended that facial stimuli incorporate the 4D space-time perspective with the proposed time-resolved methods. (shrink)

How space – mental, emotional, visual – is implicated in our constructions of reality and our art is the focus of this set of innovative essays. For the first time art theorists and historians, visual artists, literary critics and philosophers have come together to assay the problem of space both within conventional discipline boundaries and across them. What emerges is a stimulating discussion of the problem of embodied space and situated consciousness that will be of (...) interest to the general reader as well as specialists working in the fields of art history and art practice, literature, philosophy and education. (shrink)

Seeing happens effortlessly and yet is endlessly complex. Among the most fascinating aspects of visual perception is its stability and constancy. As we shift our gaze or move about the world, the light projected onto the retinas is constantly changing. Yet the surrounding objects appear stable in their properties. Psychologists have long been interested in the constancies. They have asked questions such as: How good is constancy? Is constancy a fact about how things look, or is it a (...) product of our beliefs and judgments about how things look? How can the contents of visual experience be studied experimentally? Philosophers have long been interested in characterizing visual experience and have become widely interested in the constancies more recently. As psychologists and philosophers have interacted, new questions have arisen: If experience is not as of retinal stimulation (proximal mode), but does not always exhibit constancy (or at least not in all respects), how shall we describe this intermediate state? Also, should we regard any departure from constancy as a failure of the visual system, or might it be a reasonable or adaptive response? In what circumstances is seeing highly conditioned by cognitive factors such as background assumptions, and in what circumstances not? Our volume focuses on size constancy and color constancy. It considers methodologies for studying conscious visual perception, efforts to describe visual experience in relation to constancy, what it means that constancy is not always perfect, and the conceptual resources needed for explaining visual experience. (shrink)

This paper examines Helmholtz's attempt to use empirical psychology to refute certain of Kant's epistemological positions. Particularly, Helmholtz believed that his work in the psychology of visual perception showed Kant's doctrine of the a priori character of spatial intuition to be in error. Some of Helmholtz's arguments are effective, but this effectiveness derives from his arguments to show the possibility of obtaining evidence that the structure of physical space is non-Euclidean, and these arguments do not depend on (...) his theory of vision. Helmholtz's general attempt to provide an empirical account of the "inferences" of perception is regarded as a failure. (shrink)