Fodor & Pylyshyn (1981) criticize J. J. Gibson's ecological account of perception for failing to address what I call the 'correlation problem' in visualperception. That is, they charge that Gibson cannot explain how perceivers learn to correlate detectable properties of the light with perceptible properties of the environment. Furthermore, they identify the correlation problem as a crucial issue for any theory of visualperception, what I call a 'primary problem'—i.e. a problem which plays a (...) definitive role in establishing the concerns of a particular scientific research program. If they are correct, Gibson's failure to resolve this problem would cast considerable doubt upon his ecological approach to perception. In response, I argue that both Fodor & Pylyshyn's problem itself and their proposed inferential solution embody a significant mistake which needs to be eliminated from our thinking about visualperception. As part of my response, I also suggest a Gibsonian alternative to Fodor & Pylyshyn's primary problem formulation. (shrink)
In his ecological approach to perception, james gibson introduced the concept of affordance to refer to the perceived meaning of environmental objects and events. this paper examines the relational and causal character of affordances, as well as the grounds for extending affordances beyond environmental features with transcultural meaning to include those features with culturally-specific meaning. such an extension is seen as warranted once affordances are grounded in an intentional analysis of perception. toward this end, aspects of merleau-ponty's treatment (...) of perception are explored. finally, a resolution of the apparent tension between the relational and perceiver-independent nature of affordances is presented. (shrink)
A range of arguments are presented to demonstrate that (1) human visual orientations are conceptually constituted (concept?bound); (2) the concept?boundedness of visual orientations does not require a cognitivist account according to which a mental process of ?inference? or of ?interpretation? must be postulated to accompany a purely ?optical? registration of ?wavelengths of light?, ?photons?, or contentless ?information'; (3) concept?bound visual orientations are not all instances of ?seeing as?, contrary to some currently prominent cognitivist accounts; (4) the dispute (...) between cognitivist and realist accounts about the phenomenon of ?seeing as? is spurious, and is based upon a confusion about the fundamental analytical distinction made by Wittgenstein between ?seeing? and ?seeing as'; (5) ?perceiving?, ?seeing?, and ?seeing as? are but three of a large array of verbs of human visual orientation, and are not ?master categories? under which one can subsume these other modalities; (6) one cannot deduce a continuity of human visual orientation from a continuity of photon?photoreceptor interaction, a point we characterize as the ?staggered character? of human visual orientations; (7) detailed attention to the grammars of the diverse verbs of human visual orientation can open up a domain of study which we here refer to as a ?praxiology of perception'; (8) the nature of such an inquiry can be illustrated with exemplary reference to the analysis of the properties of ?noticing? as embedded in courses of practical action; and (9) such arguments, which claim that existing perceptual theories overly homogenize what is involved in visual orientations to the world, parallel those of Stroll, who proposes that standard accounts of ?what is perceived? overly homogenize the perceptible environment. (shrink)
In this paper I present a transcendental argument based on the findings of cognitive psychology and neurophysiology which invites two conclusions: First and foremost, that a pre-condition of visualperception itself is precisely what the Aristotelian and other commonsense realists maintain, namely, the independent existence of a featured, or pre-packaged world; second, this finding, combined with other reflections, suggests that, contra McDowell and other neo-Kantians, human beings have access to things as they are in the world via non-projective (...)perception. These two conclusions taken together form the basis of Aristotelian metaphysical realism and a refutation of the neo-Kantian two-factor approach to perception. (shrink)
Although the study of visualperception has made more progress in the past 40 years than any other area of cognitive science, there remain major disagreements as to how closely vision is tied to general cognition. This paper sets out some of the arguments for both sides (arguments from computer vision, neuroscience, Psychophysics, perceptual learning and other areas of vision science) and defends the position that an important part of visualperception, which may be called early (...) vision or just vision, is prohibited from accessing relevant expectations, knowledge and utilities - in other words it is cognitively impenetrable. That part of vision is complex and articulated and provides a representation of the 3-D surfaces of objects sufficient to serve as an index into memory, with somewhat different outputs being made available to other systems such as those dealing with motor control. The paper also addresses certain conceptual and methodological issues, including the use of signal detection theory and event-related potentials to assess cognitive penetration of vision. A distinction is made among several stages in visual processing. These include, in addition to the inflexible early-vision stage, a pre-perceptual attention allocation stage and a post-perceptual evaluation, memory-accessing, and inference stage which provide several different highly constrained ways in which cognition can affect the outcome of visualperception. The paper discusses arguments that have been presented in both computer vision and psychology showing that vision is "intelligent" and involves elements of problem solving". It is suggested that these cases do not show cognitive penetration, but rather they show that certain natural constraints on interpretation, concerned primarily with optical and geometrical properties of the world, have been compiled into the visual system. The paper also examines a number of examples where instructions and "hints" are alleged to affect. (shrink)
I set out two theses. The first is Lynn Robertson’s: (a) spatial awareness is a cause of object perception. A natural counterpoint is: (b) spatial awareness is a cause of your ability to make accurate verbal reports about a perceived object. Zenon Pylyshyn has criticized both. I argue that nonetheless, the burden of the evidence supports both (a) and (b). Finally, I argue conscious visualperception of an object has a different causal role to both: (i) non-conscious (...)perception of the object, and (ii) experience, e.g. hallucination, that may be subjectively indiscriminable from, but is not, perception of the object. (shrink)
Pessoa et al. fail to make a clear distinction between visualperception and subjective visual awareness. Their most controversial claims, however, concern subjective visual awareness rather than visualperception: visual awareness is externalized to the “personal level,” thus denying the view that consciousness is a natural biological phenomenon somehow constructed inside the brain.
Standard models of visualperception hold that vision is an inferential or interpretative process. Such models are said to be superior to competing, non-inferential views in explanatory power. In particular, they are said to be capable of explaining a number of otherwise mysterious, visual phenomena such as multi-stable perception. Multi-stable perception paradigmatically occurs in the presence of ambiguous figures, single images that can give rise to two or more distinct percepts. Different interpretations are said to (...) produce the different percepts. In this paper, I argue that a non-inferential account of visualperception is just as capable of explaining multi-stable perception. I propose an embedded understanding of vision, and show how the embedded account can, after properly qualifying them, use the explanatory resources of the inferential view to explain just what such a view explains. (shrink)
This thesis falls into two parts, a characterizing part, and an explanatory part. In the first part, I outline some of the core aspects of our ordinary understanding of visualperception, and how we regard it as a means of knowing. What explains the fact that I know that the lemon before me is yellow is my visualperception: I know that the lemon is yellow because I can see it. Some explanations of how one knows (...) specify that in virtue of which one genuinely knows, as opposed to merely believes, some content. Such explanations are epistemically satisfactory explanations. We think that visual perceptual explanations of knowledge can be epistemically satisfactory. I argue that that is what it is to regard visualperception as being among our means of knowing. In the second part, I explore how we might explain the fact that visualperception is a means of knowing (assuming that it is a fact). I ask what makes it the case that visualperception is a means of knowing (in the way we ordinarily think that it is)? I suggest that part of the answer to this question is that visualperception, given the nature it has, has a reason giving role. And that is just to say that the nature of visualperception is such that visually perceiving can ensure the satisfaction of some important condition on knowledge (namely, that if one knows that something is the case one must have a good reason to believe that it is the case). In concluding I suggest that giving this sort of explanation doesn't require a specific theory of perception. (shrink)
Philosophical inquiries into the nature of consciousness have long been intrinsically tied to questions regarding the nature of the self. Although philosophers of mind seldom make reference to the role of cultural context in shaping consciousness, since antiquity culture has played a notable role in philosophical conceptions of the self. Western philosophers, from Plato to Locke, have emphasized an individualistic view of the self that is autonomous and consistent across situations, while Eastern philosophers, such as Lao Tzu and Confucius, have (...) argued for a collectivistic view of the self, one that is interconnected to others and embedded within specific social contexts and situations. Here we argue that a comprehensive theory of consciousness needs to account for the role of cultural context and its bidirectional interaction with neural and genetic mechanisms in shaping a variety of conscious phenomena, from visualperception to self- awareness. We review recent evidence of cultural variation in neurobiological mechanisms underlying these phenomena and discuss the implications of these cultural neuroscience findings for the study of consciousness. (shrink)
What is difficult to imagine is also surprising to perceive. This indicates that active visual imagery is an integral part of active visualperception. Erroneous mental transformations provide clues to prior assumptions in visual imagery, just as visual illusions provide clues to perceptual assumptions. Visual imagery and perception share generic assumptions about invariants in images of rigid objects.
Pylyshyn could have strengthened his case by avoiding side issues and by taking a sterner, firmer line on the unresolved (and perhaps unresolvable) problems plaguing the sensitivity (d') measure of top-down, cognitive effects, as well as the general (nearly utter!) lack of convincing evidence provided by proponents of the cognitive penetrability of visualperception.
Recent developments in vision science have resulted in several major changes in our understanding of human visualperception. For example, attention no longer appears necessary for "visual intelligence"--a large amount of sophisticated processing can be done without it. Scene perception no longer appears to involve static, general-purpose descriptions, but instead may involve dynamic representations whose content depends on the individual and the task. And vision itself no longer appears to be limited to the production of a (...) conscious "picture"--it may also guide processes outside the conscious awareness of the observer. (shrink)
Shepard's notion of “internalisation” is better interpreted as a simile than a metaphor. A fractal encoding model of visualperception is sketched, in which image elements are transformed in such a way as to maximise symmetry with the current input. This view, in which the transforming system embodies what has been internalised, resolves some problems raised by the metaphoric interpretation. [Hecht; Shepard].
Whether designing animals, insects, or plants, Nature draws upon symmetry and periodicity to play a fundamental role in defining the body plan. When implemented with the proper chemical mechanisms, these principles guide our bodies from single-celled embryos to bilaterally symmetric creatures with intricate periodic structures, such as the spine and rib cage. The properties of symmetry and periodicity also appear to be fundamental to visualperception. We will show that this is no coincidence, but is a consequence of (...) the fact that these properties are generated by the same underlying phenomenon, standing wave patterns formed from harmonic resonances. The symmetry in life forms arises from chemical harmonic resonances, whereas the symmetry in visualperception arises from harmonic resonances in the visual system. We will show that harmonic resonances have very interesting properties for the representation of geometrical form that make them eminently suitable for encoding geometric form for body plans as well as for visualperception. In particular, we will show that by being simultaneously invariant to perspective transformation and robust to deformation, such resonant representations have fundamental advantages over more traditional techniques. (shrink)
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. (shrink)
Three case studies offered here will support the conclusion that a successful scientific theory of visual cognition still makes room for some rather systematic and rather striking semantic indeterminacies-W.V. Quine's well-known pessimism about the wages of such indeterminacy not withstanding. The first case concerns the perception of shape, the second concerns color vision, and the third concerns the rules of inference involved in "unconscious inference" within the visual system.
Machine generated contents note: -- 1. Introduction -- Consciousness and Sensorimotor Dynamics: Methodological Issues -- 2. Computational consciousness, D. Ballard -- 3. Explaining what people say about sensory qualia, J. Kevin O'Regan -- 4. Perception, action, and experience: unraveling the golden braid, A. Clark -- The Two-Visual Systems Hypothesis -- 5. Cortical visual systems for perception and action, A.D. Milner and M.A. Goodale -- 6. Hermann Lotze's Theory of 'Local Sign': evidence from pointing responses (...) in an illusory figure, D.R. Melmoth -- Understanding Agency and Object Perception -- 7. Two visual systems and the feeling of presence, M. Matthen -- 8. Spatial coordinates and phenomenology in the two-visual systems model, P. Jacob and F. de Vignemont -- 9. Perceptual experience and the capacity to act, S. Schellenberg -- Perception and Action: Studies in Cognitive Neuroscience -- 10. Why does the perception-action functional dichotomy not match the ventral-dorsal streams in anatomical segregation: optic ataxia and the function of the dorsal stream, Y. Rossetti et al -- 11. Mapping the neglect syndrome onto neurofunctional streams, G. Vallar and F. Mancini -- 12. Motor representations and the perception of space: perceptual judgments of the boundary of action space, Y. Delevoye-Turrell -- The Role of Action and Sensorimotor Knowledge in Sensorimotor Theories of Perception -- 13. Vision without representation, A. Noe -- 14. Sensorimotor knowledge and the contents of experience, J. Kiverstein -- Boundaries of the Agent -- 15. Extended vision, R. A. Wilson. (shrink)
Visual thinking -- visual imagination or perception of diagrams and symbol arrays, and mental operations on them -- is omnipresent in mathematics. Is this visual thinking merely a psychological aid, facilitating grasp of what is gathered by other means? Or does it also have epistemological functions, as a means of discovery, understanding, and even proof? By examining the many kinds of visual representation in mathematics and the diverse ways in which they are used, Marcus Giaquinto (...) argues that visual thinking in mathematics is rarely just a superfluous aid; it usually has epistemological value, often as a means of discovery. Drawing from philosophical work on the nature of concepts and from empirical studies of visualperception, mental imagery, and numerical cognition, Giaquinto explores a major source of our grasp of mathematics, using examples from basic geometry, arithmetic, algebra, and real analysis. He shows how we can discern abstract general truths by means of specific images, how synthetic a priori knowledge is possible, and how visual means can help us grasp abstract structures. Visual Thinking in Mathematics reopens the investigation of earlier thinkers from Plato to Kant into the nature and epistemology of an individual's basic mathematical beliefs and abilities, in the new light shed by the maturing cognitive sciences. Clear and concise throughout, it will appeal to scholars and students of philosophy, mathematics, and psychology, as well as anyone with an interest in mathematical thinking. (shrink)
The two contrasting theoretical approaches to visualperception, 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 visualperception 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; visualperception theories. (shrink)
The “Perky effect” is the interference of visual imagery with vision. Studies of this effect show that visual imagery has more than symbolic properties, but these properties differ both spatially (including “pictorially”) and temporally from those of vision. We therefore reject both the literal picture-in-the-head view and the entirely symbolic view.
As many as two million people in the United Kingdom repeatedly see people, animals, and objects that have no objective reality. Hallucinations on the border of sleep, dementing illnesses, delirium, eye disease, and schizophrenia account for 90% of these. The remainder have rarer disorders. We review existing models of recurrent complex visual hallucinations (RCVH) in the awake person, including cortical irritation, cortical hyperexcitability and cortical release, top-down activation, misperception, dream intrusion, and interactive models. We provide evidence that these can (...) neither fully account for the phenomenology of RCVH, nor for variations in the frequency of RCVH in different disorders. We propose a novel Perception and Attention Deficit (PAD) model for RCVH. A combination of impaired attentional binding and poor sensory activation of a correct proto-object, in conjunction with a relatively intact scene representation, bias perception to allow the intrusion of a hallucinatory proto-object into a scene perception. Incorporation of this image into a context-specific hallucinatory scene representation accounts for repetitive hallucinations. We suggest that these impairments are underpinned by disturbances in a lateral frontal cortex–ventral visual stream system. We show how the frequency of RCVH in different diseases is related to the coexistence of attentional and visual perceptual impairments; how attentional and perceptual processes can account for their phenomenology; and that diseases and other states with high rates of RCVH have cholinergic dysfunction in both frontal cortex and the ventral visual stream. Several tests of the model are indicated, together with a number of treatment options that it generates. Key Words: Blindness; Charles Bonnet; cholinergic; cortical release; delirium; dementia; dream intrusion; hallucination; Perception and Attention Deficit (PAD) model; schizophrenia. (shrink)
L. Albertazzi, G. J. van Tonder, and D. Vishwanath (eds): Perception Beyond Inference: The Information Content of Visual Processes Content Type Journal Article Pages 53-55 DOI 10.1007/s11023-011-9253-z Authors Lorenzo Magnani, Department of Philosophy and Computational Philosophy Laboratory, University of Pavia, Pavia, Italy Journal Minds and Machines Online ISSN 1572-8641 Print ISSN 0924-6495 Journal Volume Volume 22 Journal Issue Volume 22, Number 1.
Neuroscience studies show many examples of very early modulation of visual cortex responses. It is argued that such early routing is essential for a rapid processing of information by the visual system.
One of the more compelling beliefs about vision is that it is based on representations that are coherent and complete, with everything in the visual field described in great detail. However, changes made during a visual disturbance are found to be difficult to see, arguing against the idea that our brains contain a detailed, picture-like representation of the scene. Instead, it is argued here that a more dynamic, "just-in-time" representation is involved, one with deep similarities to the way (...) that users interact with external displays. It is further argued that these similarities can provide a basis for the design of intelligent display systems that can interact with humans in highly effective and novel ways. (shrink)
Commentators agree that the Perception and Attention Deficit (PAD) model is a promising model for accounting for recurrent complex visual hallucinations (RCVH) across several disorders, though with varying detailed criticisms. Its central tenets are not modified, but further consideration of generative models of visual processing and the relationship of proto-objects and memory systems allows the PAD model to deal with variations in phenomenology. The commentaries suggest new ways to generate evidence that will test the model.
O'Regan & Noë mistakenly identify visual processing with visual experience. I outline some reasons why this is a mistake, taking my data and arguments mainly from the literature on subliminal processing.
Visual conscious perception could be grounded in a nonconscious sensorimotor domain. Although invisible, information can be processed up to the level of response activation. Moreover, these nonconscious processes are modified by actual intentions. This notion bridges a gap in the theoretical framework of O'Regan & Noë.
To see whether the mental and the neural have common attributes that could resolve some of the traditional dichotomies, we review neuroscientific data on the visual system. The results show that neuronal and perceptual function share a parallel and hierarchical architecture which is manifest not only in the anatomy and physiology of the visual system, but also in normal perception and in the deficits caused by lesions in different parts of the system. Based on the description of (...) parallel hierarchical levels of active information processing in the visual brain, we suggest a concept of dissociable levels of perception, advocating that the phenomenal perception and recognition is realized in the functional integrity of a network of reciprocal cortico-cortical connections. The properties shared by neuronal and perceptional functions provide a basis for a neuromental monism in which both functions are attributed a causal role. (shrink)
We question the usefulness of Pylyshyn's dichotomy between cognitively penetrable and cognitively impenetrable mechanisms as the basis for his distinction between cognition and early vision. This dichotomy is comparable to others that have been proposed in psychology prompting disputes that by their very nature could not be resolved. This fate is inevitable for Pylyshyn's thesis because of its reliance on internal representations and their interpretation. What is more fruitful in relation to this issue is not a difficult dichotomy, but a (...) different look at perception such as proposed by Gibson (1979). (shrink)
Lehar's lively discussion builds on a critique of neural models of vision that is incorrect in its general and specific claims. He espouses a Gestalt perceptual approach rather than one consistent with the “objective neurophysiological state of the visual system” (target article, Abstract). Contemporary vision models realize his perceptual goals and also quantitatively explain neurophysiological and anatomical data.
Seeking whether our perception produces knowledge which is not only relative or subjective perspective on things, is to be engaged in the realist/anti-realist debate regarding perception. In this article I pursue the naturalistic approach according to which the question whether perception delivers objective knowledge about the external world is inseparable from empirical investigation into mechanisms of perception. More precisely, I have focused on the dual aspect theory of perception, one of the most influential recent theories (...) of perception which unifies two traditionally opposite approaches to perception: ecological and constructivist. I have tried to show that the dualistic model of human vision does not support the majority of realist theses aimed at non-relativism, but supports only pragmatic realism about observational reports (dorsal system) and the moderate realism about observational reports (ventral system). (shrink)
Pylyshyn's argument is very similar to one made in the 1960s to the effect that vision may be influenced by spatial selective attention being directed to distinctive stimulus features, but not by mental set for meaning or membership in an ill-defined category. More recent work points to a special role for spatial attention in determining the contents of perception.
Vision has been the primary focus of naturalistic philosophical research concerning perception and perceptual experience. Guided by visual experience and vision science, many philosophers have focused upon theoretical issues dealing with the perception of objects. Recently, however, hearing researchers have discussed auditory objects. I present the case for object perception in vision, and argue that an analog of object perception occurs in auditory perception. I propose a notion of an auditory object that is stronger (...) than just that of an intentional object of audition, but that does not identify auditory objects with the ordinary material objects we see. (shrink)
A serious crisis is identified in theories of neurocomputation, marked by a persistent disparity between the phenomenological or experiential account of visualperception and the neurophysiological level of description of the visual system. In particular, conventional concepts of neural processing offer no explanation for the holistic global aspects of perception identified by Gestalt theory. The problem is paradigmatic and can be traced to contemporary concepts of the functional role of the neural cell, known as the Neuron (...) Doctrine. In the absence of an alternative neurophysiologically plausible model, I propose a perceptual modeling approach, to model the percept as experienced subjectively, rather than modeling the objective neurophysiological state of the visual system that supposedly subserves that experience. A Gestalt Bubble model is presented to demonstrate how the elusive Gestalt principles of emergence, reification, and invariance can be expressed in a quantitative model of the subjective experience of visual consciousness. That model in turn reveals a unique computational strategy underlying visual processing, which is unlike any algorithm devised by man, and certainly unlike the atomistic feed-forward model of neurocomputation offered by the Neuron Doctrine paradigm. The perceptual modeling approach reveals the primary function of perception as that of generating a fully spatial virtual-reality replica of the external world in an internal representation. The common objections to this picture-in-the-head concept of perceptual representation are shown to be ill founded. Key Words: brain-anchored; Cartesian theatre; consciousness; emergence; extrinsic constraints; filling-in; Gestalt; homunculus; indirect realism; intrinsic constraints; invariance; isomorphism; multistability; objective phenomenology; perceptual modeling; perspective; phenomenology; psychophysical parallelism; psychophysical postulate; qualia; reification; representationalism; structural coherence. (shrink)
Looking at a person’s expression is a good way of telling what she feels—what emotions she has. Why is that? Is it because we see her emotion, or is it because we infer her mental state from her expression? My claim is that there is a sense in which we do see the person’s emotion. I first argue that expressions are physical events that carry information about the emotions that produce them. I then examine evidence suggesting that specific brain areas (...) and structures are involved in the process that extracts such information and makes it available in the content of visual experience. I consider only what happens in early stages of visual processing and make no claim about the role of simulation and empathy. (shrink)
I consider the way in which spatial perception is necessary for object seeing. In section 1 I outline the operative conception of object seeing. I consider Cassam’s view that in order to see o, you must see it as spatially located (section 2). I argue that Cassam’s argument is unsound. Cassam’s argument relies on the claim that seeing o requires visual differentiation. But it is not the case that seeing o requires visual differentiation. This is because the (...) following principle is true: if S sees a visible proper part of o, then S sees o, and since there are cases in which S sees a visible proper part of o yet o is not visually differentiated for S , seeing o doesn’t require visual diﬀerentiation (section 3). In section 4 I suggest an alternative way of understanding the idea that spatial perception is necessary for object seeing. (shrink)
Ideally, psychological and phenomenological studies of visual experience should be mutually informative. In that spirit, this article outlines parts of Maurice Merleau-Ponty's phenomenological view of visual experience as a kind of independently active opaque bodily synthesis, and uses those views to (a) help ground and extend Alva Noë's rejection of the “snapshot” theory of visual experience in favor of a more enactive view of visual content, (b) critique a failing of Noë's account, and (c) show how (...) the assumptions underlying more internalist and Cartesian views of visual experience can illegitimately creep in even when they are being carefully criticized. (shrink)
In their target article, O'Regan & Noë (O&N) give convincing arguments for there being no elaborate internal representation of the outside world. We show two more categories of empirical results that can easily be understood within the view that the world serves as an outside memory that is probed only when specific information is needed.
Through computational modeling, here we examine whether visual and task characteristics of writing systems alone can account for lateralization differences in visual word recognition between different languages without assuming influence from left hemisphere (LH) lateralized language processes. We apply a hemispheric processing model of face recognition to visual word recognition; the model implements a theory of hemispheric asymmetry in perception that posits low spatial frequency biases in the right hemisphere and high spatial frequency (HSF) biases in (...) the LH. We show two factors that can influence lateralization: (a) Visual similarity among words: The more similar the words in the lexicon look visually, the more HSF/LH processing is required to distinguish them, and (b) Requirement to decompose words into graphemes for grapheme-phoneme mapping: Alphabetic reading (involving grapheme-phoneme conversion) requires more HSF/LH processing than logographic reading (no grapheme-phoneme mapping). These factors may explain the difference in lateralization between English and Chinese orthographic processing. (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)
Perceptual experience can be explained by contextualized brain dynamics. An inner loop of ongoing activity within the brain produces dynamic patterns of synchronization and de- synchronization that are necessary, but not sufficient, for visual experience. This inner loop is controlled by evolution, development, socialization, learning, task and perception- action contingencies, which constitute an outer loop. This outer loop is sufficient, but not necessary, for visual experience. Jointly, the inner and outer loop may offer sufficient and necessary conditions (...) for the emergence of visual experience. This hypothesis has methodological, empirical, theoretical, and philosophical implications. (shrink)
"This collection of classic essays in the study of visual culture fills a major gap in this new and expanding intellectual field. Its major strength is its insistence on the importance of three central aspects of the study of visual culture: the sign, the institution and the viewing subject. It will provide readers, teachers and students with an essential text in visual and cultural studies." - Janet Wolff, University of Rochester Visual Culture: The Reader provides an (...) invaluable resource of over 30 key statements from a wide range of disciplines. Although underpinned by a focus on contemporary cultural theory, this reader puts issues of visual culture and the rhetoric of the image at centre stage. Divided into three parts, The Culture of the Visual, Regulating Photographic Meaning, Looking and Subjectivity, this reader enables students to make hitherto unmade connections across art, film and photography history and theory, semiotics, history, semiotics and communications, media studies, and cultural theory. The key statements are from the work of: Visual Culture: The Reader sets the agenda for the study of Visual Culture and will be an essential sourcebook for researchers and students alike. This is the reader for the module The Image and Visual Culture (D850) - part of The Open University Masters in Social Sciences Programme. (shrink)
It has been shown that visual awareness in the blind hemifield of hemianopic cats that have undergone unilateral ablations of visual cortex can be restored by sectioning the commissure of the superior colliculus or by destroying a portion of the substantia nigra contralateral to the cortical lesion (the Sprague effect). We propose that the visual awareness that is recovered is due to synchronized oscillatory activities in the superior colliculus ipsilateral to the cortical lesion. These oscillatory activities are (...) normally partially suppressed by the inhibitory, GABAergic contralateral nigrotectal projection, and the destruction of the substantia nigra, or the sectioning of the collicular commissure, disinhibits the collicular neurons, causing an increase in the extent of oscillatory activity and/or synchronization between activities at different sites. This increase in the oscillatory and synchronized character is sufficient for the activities to give rise to visual awareness. We argue that in rodents and lower vertebrates, normal visual awareness is partly due to synchronized oscillatory activities in the optic tectum and partly due to similar activities in visual cortex. It is only in carnivores and primates that visual awareness is wholly due to cortical activities. Based on von Baerian recapitulation theory, we propose that, even in humans, there is a period in early infancy when visual awareness is partially due to activities in the superior colliculus, but that this awareness gradually disappears as the nigrotectal projection matures. (shrink)
The importance of the visual aspects of the fantastic reverberates even into theory, as shown by several researchers throughout the last decades. These researchers distinguished themselves from their predecessors, whose definition of the fantastic implied mainly an involvement of the intellect. From the many forms it takes, we will concentrate in this article on the thematic level of the text, or, more precisely, on the use of the mirrors and other forms of reflection as a form of exploration of (...) the self in the fantastic tales of the Belgian writer Thomas Owen. Vision becomes more than a common way of perceiving reality for the writer’s characters, now looking to shed a new light on the unknown and offering an insight on things beyond reason. (shrink)