The Dimensionality of Visual Space

The empirical study of visual space (VS) has centered on determining its geometry, whether it is a perspective projection, flat or curved, Euclidean or non-Euclidean, whereas the topology of space consists of those properties that remain invariant under stretching but not tearing. For that reason distance is a property not preserved in topological space whereas the property of spatial order is preserved. Specifically the topological properties of dimensionality, orientability, continuity, and connectivity define “real” space as studied by physics and are the spatial properties that characterize the physical universe as being an integral whole. By contrast the geometrical analysis of VS has taken little cognizance of its topology. Instead such properties have been presupposed a priori rather than being established a posteriori by empirical means, perhaps because these properties are self-evident. Applying the method of coordinative definition expounded by Hans Reichenbach for determining geometrical and topological properties of physical space (PS), it can be shown that VS fulfills the topological criteria of being a “real” space sui generis. Though theorized to be produced by the brain, the topology of VS is not topologically equivalent (homeomorphic) with the structure and activity of the brain because, as will be shown, the topology of VS cannot be formed from the topology of the brain without tearing and/or cutting and pasting.     

Representation and constraints: the inverse problem and the structure of visual space

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 (1) that visual space exhibits contraction in all three dimensions with increasing distance from the observer, (2) that experienced features of this contraction (including the apparent convergence of lines in visual experience that are produced from physically parallel stimuli in ordinary viewing conditions) are not the same as would be the experience of a perspective projection onto a frontoparallel plane, and (3) 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.     

动、静态视觉信息在真实世界视觉搜索中的作用

真实环境中的视觉搜索是人和动物赖以生存的重要能力。目前的视觉搜索研究多使用静态的观察者和静止的二维搜索对象, 侧重于探究注意在搜索中的作用; 现有的视觉搜索理论模型主要概括了影响搜索的自上而下的注意因素, 而将自下而上影响因素简单归结为影像显著性, 然而在真实环境中, 观察者或搜索对象是可以运动的, 搜索时可利用的视觉信息包括动态光流和静态影像结构信息。已有的视觉识别研究发现这两种信息相结合可以使观察者准确持久地识别场景、事件和三维结构。在现有视觉搜索理论模型中引入两种视觉信息可以较好还原真实环境中的搜索任务。我们提出研究构想和实验方案,探究利用动、静态视觉信息的视觉搜索过程, 从而完善现有的视觉搜索模型。我们认为充分利用环境信息可以提高搜索效率, 且在视觉搜索训练和智能搜索设计等方面有重要的应用价值。     

Against Radical Quantum Ontologies

Some theories of quantum mechanical phenomena endorse wave function realism, according to which the physical space we inhabit is very different from the physical space we appear to inhabit. In this paper I explore an argument against wave function realism that appeals to a type of simplicity that, although often overlooked, plays a crucial role in scientific theory choice. The type of simplicity in question is simplicity of fit between the way a theory says the world is and the way the world appears to be. This argument can be understood as one way of spelling out the so‐called “incredulous stare objection” that is sometimes leveled against surprising metaphysical theories.     

Geometrical structures of photographic and stereoscopic spaces

Two experiments were conducted to investigate the geometrical structures of photographic and stereoscopic spaces. In Experiment 1, it was investigated how accurately photographic space reproduces real physical space, and the geometrical structure of photographic space was compared with that of visual space. As a result, the mapping function of distance between photographic and physical spaces (delta = ad(b)) shows that a and b range from 0.96-1.1 and 0.69-0.78. The mapping function of angle between photographic and physical spaces (phi = g phi(h)) shows that g and h range from 2.37-5.29 and 0.74-0.97. Further, photographic space has larger anisotropic property than visual space and photographic space may be hyperbolic. In Experiment 2, the geometrical structure of stereoscopic space was compared with that of visual space. It was found that stereoscopic space was almost the same as visual space.     

PHYSICAL REALISM

Physical realism is the thesis that the world is more or less as present‐day physical theory says it is, i.e. a mind‐independent reality, that consists fundamentally of physical objects that have causal powers, are located in space and time, belong to natural kinds, and interact causally with each other in various natural kinds of ways. It is thus a modern form of physicalism that takes due account of the natural kinds structure of the world. It is a thesis that many present‐day scientific realists would surely accept. Indeed, some might say that physical realism just is scientific realism, but under another name. However, the argument that is presented for physical realism is not the standard one for scientific realism. It is not a two‐stage argument from the success of science to the truth of scientific theories to the reality of the entities postulated in these theories. It is more powerful than this, because it is more direct, and its premisses are more secure. It is more direct, because it develops what is basically a physicalist ontology as the only plausible metaphysical explanation of the new scientific image of the world. It is more secure, in that it does not depend, as the standard argument does, on any doubtful generalisations about the nature or role of scientific theory.     

The Epistemological Status of Vision and its Implications for Design

Computational theories of vision typically rely on the analysis of two aspects of human visual function: (1) object and shape recognition (2) co-calibration of sensory measurements. Both these approaches are usually based on an inverse-optics model, where visual perception is viewed as a process of inference from a 2D retinal projection to a 3D percept within a Euclidean space schema. This paradigm has had great success in certain areas of vision science, but has been relatively less successful in understanding perceptual representation, namely, the nature of the perceptual encoding. One of the drawbacks of inverse-optics approaches has been the difficulty in defining the constraints needed to make the inference computationally tractable (e.g. regularity assumptions, Bayesian priors, etc.). These constraints, thought to be learned assumptions about the nature of the physical and optical structures of the external world, have to be incorporated into any workable computational model in the inverse-optics paradigm. But inference models that employ an inverse optics plus structural assumptions approach inevitably result in a naïve realist theory of perceptual representation. Another drawback of inference models for theories of perceptual representation is their inability to explain central features of the visual experience. The one most evident in the process and visual understanding of design is the fact that some visual configurations appear, often spontaneously, as perceptually more coherent than others. The epistemological consequences of inferential approaches to vision indicate that they fail to capture enduring aspects of our visual experience. Therefore they may not be suited to a theory of perceptual representation, or useful for an understanding of the role of perception in the design process and product.     

Visual perception of collinearity

In a metrical space, there exists an intimate relation between collinearity and parallelity. In particular, in a Riemannian space collinearity is just a special case of parallelity. Is this true for visual space as well? We investigated the visual perception of collinearity by having subjects align two bars in the horizontal plane at eye height. The distances of the bars from the subject and the angles at which they were placed were varied. We found deviations of up to 22 degrees. The deviations of the left and right bars could be split into two independent components: namely, the sum and the difference of the deviations of the left and right bars. We found that the former depended only on the ratio between the distances of each bar from the subject, whereas the latter was largely independent of the positions of the bars. The difference in deviations corresponded to the deviation from parallelity. Compared with the results in the parallelity task (Cuijpers, Kappers, & Koenderink, 2000b), the deviations from parallel were much smaller. As a consequence, the results of the two experiments cannot be described by the same Riemannian geometry. This indicates that the intrinsic geometry of visual space differs across tasks. This is conceivable if the intrinsic geometry of visual space is operationally defined.     

Can a nonspecific bias toward top-heavy patterns explain newborns' face preference?

This study examined newborns' face preference using images of natural and scrambled faces in which the location of the inner features was distorted. The results demonstrate that newborns' face preference is not confined to schematic configurations, but can be obtained also with veridical faces. Moreover, this phenomenon is not produced by a specific bias toward the face geometry, but derives from a domain-general bias toward configurations with more elements in the upper than in the lower half (i.e., top-heavy patterns). These results suggest that it may be unnecessary to assume the existence of a prewired tendency to orient toward the face geometry, and support the idea that faces do not possess a special status in newborns' visual world.     

Representationalism and the Metonymic Fallacy

Representationalism in cognitive science holds that semantic meaning should be explained by representations in the mind or brain. In this paper it is argued that semantic meaning should instead be explained by an abstract theory of semantic machines -- machines with predicative capability. The concept of a semantic machine (like that of a Turing machine or of Dennett's intentional systems) is not a physical concept -- although it has physical implementations. The predicative competence of semantic machines is defined in terms of independent agreement alone (cf. independent, and yet synchronised, clocks). Abstract theories are analysed as systems of quasi-apriori rules for abstract predicates. A relatively limited number of such theories and a few fundamental dimensions (space, time, mass, etc.) are today assumed to exhaust physical reality. However, that assumption need not be in conflict with predicates that cannot be defined in physical terms – for instance the functional and intentional terms that are crucial for cognitive science.     

Solving the "real" mysteries of visual perception: the world as an outside memory.

Visual science is currently a highly active domain, with much progress being made in fields such as colour vision, stereo vision, perception of brightness and contrast, visual illusions, etc. But the "real" mystery of visual perception remains comparatively unfathomed, or at least relegated to philosophical status: Why it is that we can see so well with what is apparently such a badly constructed visual apparatus? In this paper I will discuss several defects of vision and the classical theories of how they are overcome. I will criticize these theories and suggest an alternative approach, in which the outside world is considered as a kind of external memory store which can be accessed instantaneously by casting one's eyes (or one's attention) to some location. The feeling of the presence and extreme richness of the visual world is, under this view, a kind of illusion, created by the immediate availability of the information in this external store.     

A critical review of the physicalistic approaches of the mind and consciousness

The aim of this paper is to construct a critical evaluation of the advantages and disadvantages of the physicalistic theory concerning mental phenomena and consciousness. Physicalism can, better than other theories, explain mental phenomena, such as intentionality and reasonability of human beings and other biological organisms. Modern neuroscience corroborates the conviction that the brain is a physical mind capable of giving meaning to, evaluating and further cognitively and behaviorally transforming complex aspects of the world. On the other hand, the emergence of consciousness from brain states seems to be a paradoxical, intransparent, physical coincidence hardly explained by the mental function of the brain at the physical level. Moreover, the intentionality and reasonability of psychic phenomena per se cannot be explained as a repercussion of the same attributes characterizing the brain function. In conclusion, the old debate between physicalism and other philosophical theories remains open. It can be expected that the progress of sciences will inspire novel approaches to the problem of the relations between matter, mind and consciousness.     

Visual categorization of social interactions

Prominent theories of action recognition suggest that during the recognition of actions the physical patterns of the action is associated with only one action interpretation (e.g., a person waving his arm is recognized as waving). In contrast to this view, studies examining the visual categorization of objects show that objects are recognized in multiple ways (e.g., a VW Beetle can be recognized as a car or a beetle) and that categorization performance is based on the visual and motor movement similarity between objects. Here, we studied whether we find evidence for multiple levels of categorization for social interactions (physical interactions with another person, e.g., handshakes). To do so, we compared visual categorization of objects and social interactions (Experiments 1 and 2) in a grouping task and assessed the usefulness of motor and visual cues (Experiments 3, 4, and 5) for object and social interaction categorization. Additionally, we measured recognition performance associated with recognizing objects and social interactions at different categorization levels (Experiment 6). We found that basic level object categories were associated with a clear recognition advantage compared to subordinate recognition but basic level social interaction categories provided only a little recognition advantage. Moreover, basic level object categories were more strongly associated with similar visual and motor cues than basic level social interaction categories. The results suggest that cognitive categories underlying the recognition of objects and social interactions are associated with different performances. These results are in line with the idea that the same action can be associated with several action interpretations (e.g., a person waving his arm can be recognized as waving or greeting).     

Competition for consciousness among visual events: the psychophysics of reentrant visual processes

Advances in neuroscience implicate reentrant signaling as the predominant form of communication between brain areas. This principle was used in a series of masking experiments that defy explanation by feed-forward theories. The masking occurs when a brief display of target plus mask is continued with the mask alone. Two masking processes were found: an early process affected by physical factors such as adapting luminance and a later process affected by attentional factors such as set size. This later process is called masking by object substitution, because it occurs whenever there is a mismatch between the reentrant visual representation and the ongoing lower level activity. Iterative reentrant processing was formalized in a computational model that provides an excellent fit to the data. The model provides a more comprehensive account of all forms of visual masking than do the long-held feed-forward views based on inhibitory contour interactions.     

肢体运动信息如何在工作记忆中存储?

肢体运动(空间位置运动与身体模式运动)是个体与环境交互作用的重要途径。以往行为学和脑成像研究分别探讨了空间位置运动信息和身体模式运动信息的工作记忆存储问题, 发现两种肢体运动信息的存储均独立于语音环、视空间画板的视觉子系统, 需要视空间画板的空间子系统的参与; 两种肢体运动信息激活的脑区(运动相关皮层)独立于语音环、视空间画板的视觉子系统和空间子系统, 并存在差异。这表明, 现有的工作记忆多成分模型不能完全解释肢体运动信息的存储。据此可推论, 工作记忆系统中可能存在一个负责处理肢体运动信息的“肢体运动系统”, 其隶属于视空间画板, 与视觉子系统和空间子系统并存; 其激活脑区因肢体运动的不同而存在差异。     

The theory‐ladenness of observations,the role of scientific instruments,and the Kantian a priori

During the last decades it has become widely accepted that scientific observations are ‘theory‐laden’. Scientists ‘see’ the world with their theories or theoretical presuppositions. In the present paper it is argued that they ‘see’ with their scientific instruments as well, as the uses of scientific instruments is an important characteristic of modern natural science. It is further argued that Euclidean geometry is intimately linked to technology, and hence that it plays a fundamental part in the construction and operation of scientific instruments. Finally, Euclidean geometry is compared to fractal geometry, and the question of its a priori status is raised. Although the position that Euclidean geometry is a priori in the original Kantian sense is untenable, the paper concludes that in some restricted sense Euclidean geometry may be said to be a priori.     

Concavities as basic features in visual search: evidence from search asymmetries

Concave cusps and negative curvature minima play an important role in many theories of visual shape perception. Cusps and minima are taken to be part boundaries, used to segment an object into parts. Because of their important role in determining object structure and because there is some evidence that object structure is processed in parallel, it might be expected that concave cusps and negative curvature minima are processed preferentially. We tested this conjecture in several visual search experiments. Visual search for a target with a concave cusp among totally convex distractors yields nearly flat slopes (< 10 msec/item) for both present and absent trials. Reversing the roles of the target and the distractor results in inefficient search. The same asymmetry is found when the concave cusp is replaced by other types of concavity. We conclude, therefore, the concavities can serve as basic features in visual search experiments. This conclusion implies that the unit of selection in a visual search task is an object, rather than a location.     

拓扑几何在知觉组织与空间概念形成中的运用

陈霖的拓扑知觉理论运用几何性质解释知觉组织,并强调拓扑性质的优先性——拓扑知觉是其他几何知觉的基础,拓扑知觉先于其他几何知觉发生。皮亚杰的拓扑首位理论认为儿童的空间概念发展顺序为先发展拓扑几何概念,之后再发展射影与欧式几何概念。两大理论都运用拓扑性质来解释心理现象,其研究对象、研究方法存在很大不同,但它们在理论结构上具有高度一致性,对几何学在心理学上的运用有非常重要的启示意义。     

Quality spaces: Mental and physical

Perceptual-role theories of mental qualities hold that we can discover the nature of a being’s mental qualities by investigating that being’s capacity to make perceptual discriminations. Many advocates of perceptual-role theories hold that the best explanation of these capacities is that mental quality spaces are homomorphic to the spaces of the physical properties that they help to discriminate. This paper disputes this thesis on largely empirical grounds, and offers an alternative. The alternative explains interesting patterns in our perception of color differences and similarities across edges, emphasizing the importance of visual discontinuities. Further, it provides a simple explanation of the intransitivity of indiscriminability. The homomorphism thesis can explain this intransitivity only with the addition of an independently unsupported empirical hypothesis. Also, in contrast to the homomorphism thesis, the alternative view is perfectly consistent with empirical data that suggest (a) that the visual system uses the dynamic allocation of a limited range of responses in order to discriminate a wider range of physical stimuli and (b) that we are much better at detecting changes in relative luminance than changes in absolute luminance. Moreover, it does all this while using a more efficient strategy for encoding sensory information.