Although the study of visual perception 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 and defends the position that an important part of visual perception, 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 visual perception. 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)

Standard models of visual perception 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 visual perception 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)

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

This is a book about how we see: the environment around us (its surfaces, their layout, and their colors and textures); where we are in the environment; whether or not we are moving and, if we are, where we are going; what things are good for; how to do things (to thread a needle or drive an automobile); or why things look as they do.The basic assumption is that vision depends on the eye which is connected to the brain. The (...) author suggests that natural vision depends on the eyes in the head on a body supported by the ground, the brain being only the central organ of a complete visual system. When no constraints are put on the visual system, people look around, walk up to something interesting and move around it so as to see it from all sides, and go from one vista to another. That is natural vision—and what this book is about. (shrink)

Several arguments are considered which purport to demonstrate the impossibility of theory-neutral observation. The most important of these infers the continuity of observation with theory from the presumed continuity of perception with cognition, a doctrine widely espoused in recent cognitive psychology. An alternative psychological account of the relation between cognition and perception is proposed and its epistemological consequences for the observation/theory distinction are then explored.

The doctrine that the character of our perceptual knowledge is plastic, and can vary substantially with the theories embraced by the perceiver, has been criticized in a recent paper by Fodor. His arguments are based on certain experimental facts and theoretical approaches in cognitive psychology. My aim in this paper is threefold: to show that Fodor's views on the impenetrability of perceptual processing do not secure a theory-neutral foundation for knowledge; to show that his views on impenetrability are almost certainly (...) false; and to provide some additional arguments for, and illustrations of, the theoretical character of all observation judgments. (shrink)

Highlights of a difficult history -- The preliminary identification of our topic -- Approaches -- Bradley's protest -- James's disjunctive theory -- The source of Bradley's dissatisfaction -- Behaviourism and after -- Heirs of Bradley in the twentieth century -- The underlying metaphysical issue -- Explanatory tactics -- The basic distinction -- Metaphysical categories and taxonomies -- Adverbialism, multiple realizability, and natural kinds -- Adverbialism and levels of explanation -- Taxonomies and supervenience relations -- Rejecting the process : first view (...) -- Supervenience-failure -- The modal commitments of the process : first view -- The interference argument : a putative problem for adverbialist accounts -- Cognitive unison -- The problem with attitude based adverbialism -- Gilbert Ryle and Alan White -- White's argument against disposition-based adverbialism -- The cognitive unison theory -- Tasks -- Cognitive processes -- Potential service of a task -- Superordinate tasks -- Some features of the theory -- Divided attention -- Degrees of attention and merely partial attention -- The causal life of attention -- Mental causation -- How to respond to mental causation objections -- The causal role of attention -- Attention as an enabling condition -- Counterfactuals -- The causal relevance of attention per se -- Counterfactuals and causally relevant properties -- Objections to counterfactual analysis of causation and of causal relevance -- The extrinsicness of unison -- The privative character of unison and the problem of absence causation -- Causal exclusion -- Consequences for cognitive psychology -- Psychology and metaphysics -- The metaphysical commitments of the process-identifying project -- The diverse explanatory construals of current psychological results -- Reasons for deflation -- Inductively unreliable properties -- Questions without answers -- The positive payoff -- Philosophical work for the theory of attention -- Putting attention to philosophical work -- Attention and reference -- Attention and consciousness -- Prospects for optimism. (shrink)

This study synthesizes current information from the various fields of cognitive science in support of a new and exciting theory of mind. Most psychologists study horizontal processes like memory and information flow; Fodor postulates a vertical and modular psychological organization underlying biologically coherent behaviors. This view of mental architecture is consistent with the historical tradition of faculty psychology while integrating a computational approach to mental processes. One of the most notable aspects of Fodor's work is that it articulates features not (...) only of speculative cognitive architectures but also of current research in artificial intelligence. (shrink)

The theory of visual perception that Irvin Rock develops and supports in this book with numerous original experiments, views perception as the outcome of a process of unconscious inference, problem solving, and the building of structural descriptions of the external world.

This textbook on vision reflects the integrated computational approach of modern research scientists, combining psychological, computational and neuroscientific perspectives.

"Perception is not something that happens to us, or in us," writes Alva Noe. "It is something we do." In Action in Perception, Noe argues that perception and perceptual consciousness depend on capacities for action and thought — that ...

I recently discovered that work I was doing in the laboratory and in theoretical writings was implicitly taking a position on a set of questions that philosophers had been worrying about for much of the past 30 or more years. My clandestine involvement in philosophical issues began when a computer science colleague and I were trying to build a model of geometrical reasoning that would draw a diagram and notice things in the diagram as it drew it (Pylyshyn, Elcock, Marmor, (...) & Sander, 1978). One problem we found we had to face was that if the system discovered a right angle it had no way to tell whether this was the intersection of certain lines it had drawn earlier while constructing a certain figure, and if so which particular lines they were. Moreover, the model had no way of telling whether this particular right angle was identical to some bit of drawing it had earlier encountered and represented as, say, the base of a particular triangle. There was, in other words, no way to determined the identity of an element (I use the term “element” when referring to a graphical unit such as used in experiments. Otherwise when speaking informally I use the term “thing” on the grounds that nobody would mistake that term for a technical theoretical construct. Eventually I end up calling them “Visual Objects” to conform to usage in psychology) at two different times if it was represented differently at those times. This led to some speculation about the need for what we called a “finger” that could be placed at a particular element of interest and that could be used to identify it as particular token thing (the way you might identify a particular feature on paper by labeling it). In general we needed something like a finger that would stay attached to a particular element and could be used to maintain a correspondence between the individual element that was just noticed now and one that had been represented in some fashion at an earlier time. The idea of such fingers (which.... (shrink)

We investigated the possible causes of perceptual switching in ambiguous figures. Ambiguous figures are a special class of visual stimuli that can give rise to at least two alternative interpretations. Because the figures themselves stay the same, these stimuli are particularly suitable to study the dynamic changes in our visual apparatus that enable us to see the world in different ways. Recent studies stress the importance of both low-level and high-level processes in switching. We show that these processes lead to (...) switching independently, and that, when they co-occur, they do not occur at exactly the same time.We take these results to indicate that perceptual switching is a radically multiply realizable process, in that various neurological states can instantiate it in a single individual from time to time. We reflect on the consequences of this conclusion for experiential realism, in particular the notion that embodiment misleads us in identifying psychological types. (shrink)

Can one see one thing as another without possessing a concept of it? The answer to this question is intuitively negative. This is because seeing x as F is usually taken to consist in the application of the concept F to x . Seeing the duck-rabbit figure as a duck figure, for instance, involves applying the concept DUCK to the figure; thus, one cannot see the figure as the figure of a duck unless one has the concept of a duck (...) and is able to deploy it when looking at the figure. Nearly by definition, then, one cannot see x as F without possessing a concept of F. Contrary to this line of reasoning, this article treats the question of whether we can see x as F without possessing a concept of F as an open and partially empirical question. Seeing x as F involves seeing x in a certain way, namely as F, and whether concepts are required in order to see something in a certain way is an open question. Accordingly, what follows offers a proposal for an alternative way of understanding seeing–as that does not appeal to concept application. (shrink)

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