This paper argues that a theory of situated vision, suited for the dual purposes of object recognition and the control of action, will have to provide something more than a system that constructs a conceptual representation from visual stimuli: it will also need to provide a special kind of direct (preconceptual, unmediated) connection between elements of a visual representation and certain elements in the world. Like natural language demonstratives (such as `this' or `that') this direct connection allows entities to be (...) referred to without being categorized or conceptualized. Several reasons are given for why we need such a preconcep- tual mechanism which individuates and keeps track of several individual objects in the world. One is that early vision must pick out and compute the relation among several individual objects while ignoring their properties. Another is that incrementally computing and updating representations of a dynamic scene requires keeping track of token individuals despite changes in their properties or locations. It is then noted that a mechanism meeting these requirements has already been proposed in order to account for a number of disparate empiri- cal phenomena, including subitizing, search-subset selection and multiple object tracking (Pylyshyn et al., Canadian Journal of Experimental Psychology 48(2) (1994) 260). This mechanism, called a visual index or FINST, is brie. (shrink)

Large changes in a scene often become difficult to notice if made during an eye movement, image flicker, movie cut, or other such disturbance. It is argued here that this _change blindness_ can serve as a useful tool to explore various aspects of vision. This argument centers around the proposal that focused attention is needed for the explicit perception of change. Given this, the study of change perception can provide a useful way to determine the nature of visual attention, and (...) to cast new light on the way that it is?and is not?involved in visual perception. To illustrate the power of this approach, this paper surveys its use in exploring three different aspects of vision. The first concerns the general nature of _seeing_. To explain why change blindness can be easily induced in experiments but apparently not in everyday life, it is proposed that perception involves a _virtual representation_, where object representations do not accumulate, but are formed as needed. An architecture containing both attentional and nonattentional streams is proposed as a way to implement this scheme. The second aspect concerns the ability of observers to detect change even when they have no visual experience of it. This _sensing_ is found to take on at least two forms: detection without visual experience (but still with conscious awareness), and detection without any awareness at all. It is proposed that these are both due to the operation of a nonattentional visual stream. The final aspect considered is the nature of visual attention itself?the mechanisms involved when _scrutinizing_ items. Experiments using controlled stimuli show the existence of various limits on visual search for change. It is shown that these limits provide a powerful means to map out the attentional mechanisms involved. (shrink)

There has recently been much interest in the role of attention in controlling action. The role has been mischaracterized as an element in necessary and sufficient conditions on agential control. In this paper I attempt a new characterization of the role. I argue that we need to understand attentional control in order to fully understand agential control. To fully understand agential control we must understand paradigm exercises of agential control. Three important accounts of agential control—intentional, reflective, and goal-represented control—do not (...) fully explain such exercises. I argue that understanding them requires understanding how deployments of visual attention implement flexible occurrent control, or a capacity to flexibly adjust the degree of control that individuals exercise over their actions. While such deployments of attention are neither necessary nor sufficient for exercising agential control, they constitute an attentional skill for controlling action, understanding which is central to fully understanding agential control. We can appreciate its centrality if we appreciate that this attentional skill for controlling action is plausibly crucial to acting non-negligently. (shrink)

This book draws on Iris Murdoch's philosophy to explore questions related to the importance of attention in ethics. In doing so, it also engages with Murdoch's ideas about the existence of a moral reality, the importance of love, and the necessity but also the difficulty, for most of us, of fighting against our natural self-centred tendencies. Why is attention important to morality? This book argues that many moral failures and moral achievements can be explained by attention. Not only our actions (...) and choices, but the possibilities we choose among, and even the meaning what we perceive, are to a large extent determined by whether we pay attention, and what we attend do. In this way, the book argues that attention is fundamental, though often overlooked, in morality. While the book's discussion of attention revolves primarily around Murdoch's thought, it also engages significantly with Simone Weil, who introduced the concept of attention in a spiritual context. The book also engages with contemporary debates concerning moral perception and motivation, empirical psychology, animal ethics, and Buddhist philosophy. The Ethics of Attention will be of interest to researchers and advanced students working on Iris Murdoch, Simone Weil, ethics and moral psychology, and the philosophy of attention. (shrink)

In this paper I propose a model of demonstrative thought. I distinguish token-demonstratives, that pick out individuals, from type-demonstratives, that pick out kinds, or properties, and provide a similar treatment for both. I argue that it follows from my model of demonstrative thought, as well as from independent considerations, that demonstration, as a mental act, operates directly on mental representations, not external objects. That is, though the relation between a demonstrative and the object or property demonstrated is semantically direct, the (...) mechanism by which a demonstrative acquires its referent involves mediation by a perceptual representation. Finally, I argue that so-called 'demonstrative concepts'—which I treat as type-demonstratives—cannot perform the various philosophical functions that have been assigned to them. (shrink)

What is attention? Attention is often seen as a subject matter for the hard sciences of cognitive and brain processes, and is understood in terms of sub-personal mechanisms and processes. Correspondingly, there still is a stark contrast between the central role attention plays for the empirical investigation of the mind in psychology and the neurosciences, and its relative neglect in philosophy. Yet, over the past years, several philosophers have challenged the standard conception. A number of interesting philosophical questions concerning the (...) nature of attention arise. This article provides an introduction to contemporary debates concerning these questions. In particular, it discusses the question of how the pre-theoretic conception of attention might be reconciled with a scientific conception, arguments that provide support for an anti-reductivist theory of attention, and sketches several recent anti-reductivist theories and their inter-relations. (shrink)

We propose a framework for including information‐processing bounds in rational analyses. It is an application of bounded optimality (Russell & Subramanian, 1995) to the challenges of developing theories of mechanism and behavior. The framework is based on the idea that behaviors are generated by cognitive mechanisms that are adapted to the structure of not only the environment but also the mind and brain itself. We call the framework computational rationality to emphasize the incorporation of computational mechanism into the definition of (...) rational action. Theories are specified as optimal program problems, defined by an adaptation environment, a bounded machine, and a utility function. Such theories yield different classes of explanation, depending on the extent to which they emphasize adaptation to bounds, and adaptation to some ecology that differs from the immediate local environment. We illustrate this variation with examples from three domains: visual attention in a linguistic task, manual response ordering, and reasoning. We explore the relation of this framework to existing “levels” approaches to explanation, and to other optimality‐based modeling approaches. (shrink)

_René Descartes proposed an interactive dualism that posits an interaction between the_ _mind of a human being and some of the matter located in his or her brain. Isaac Newton_ _subsequently formulated a physical theory based exclusively on the material/physical_ _part of Descartes’ ontology. Newton’s theory enforced the principle of the causal closure_ _of the physical, and the classical physics that grew out of it enforces this same principle._ _This classical theory purports to give, in principle, a complete deterministic account (...) of the_ _physically described properties of nature, expressed exclusively in terms of these_ _physically described properties themselves. Orthodox contemporary physical theory_ _violates this principle in two separate ways. First, it injects random elements into the_ _dynamics. Second, it allows, and also requires, abrupt probing actions that disrupt the_ _mechanistically described evolution of the physically described systems. These probing_ _actions are called Process 1 interventions by von Neumann. They are psycho-physical_ _events. Neither the content nor the timing of these events is determined either by any_ _known law, or by the afore-mentioned random elements. Orthodox quantum mechanics_ _considers these events to be instigated by choices made by conscious agents. In von_ _Neumann’s formulation of quantum theory each such intervention acts upon the state of_ _the brain of some conscious agent. Thus orthodox von Neumann contemporary physics_ _posits an interactive dualism similar to that of Descartes. But in this quantum version the_ _effects of the conscious choices upon our brains are controlled, in part, by the known_ _basic rules of quantum physics. This theoretically specified mind-brain connection allows_ _many basic psychological and neuropsychological findings associated with the apparent_ _physical effectiveness of our conscious volitional efforts to be explained in a causal and_ _practically useful way.. (shrink)

Neuropsychological research on the neural basis of behaviour generally posits that brain mechanisms will ultimately suffice to explain all psychologically described phenomena. This assumption stems from the idea that the brain is made up entirely of material particles and fields, and that all causal mechanisms relevant to neuroscience can therefore be formulated solely in terms of properties of these elements. Thus, terms having intrinsic mentalistic and/or experiential content (e.g. ‘feeling’, ‘knowing’ and ‘effort’) are not included as primary causal factors. This (...) theoretical restriction is motivated primarily by ideas about the natural world that have been known to be fundamentally incorrect for more than three-quarters of a century. Contemporary basic physical theory differs profoundly from classic physics on the important matter of how the consciousness of human agents enters into the structure of empirical phenomena. The new principles contradict the older idea that local mechanical processes alone can account for the structure of all observed empirical data. Contemporary physical theory brings directly and irreducibly into the overall causal structure certain psychologically described choices made by human agents about how they will act. This key development in basic physical theory is applicable to neuroscience, and it provides neuroscientists and psychologists with an alternative conceptual framework for describing neural processes. Indeed, owing to certain structural features of ion channels critical to synaptic function, contemporary physical theory must in principle be used when analysing human brain dynamics. The new framework, unlike its classic-physics-based predecessor, is erected directly upon, and is compatible with, the prevailing principles of physics. It is able to represent more adequately than classic concepts the neuroplastic mechanisms relevant to the growing number of empirical studies of the capacity of directed attention and mental effort to systematically alter brain function.. (shrink)

Goal‐directed cognition is often discussed in terms of specialized memory structures like the “goal stack.” The goal‐activation model presented here analyzes goal‐directed cognition in terms of the general memory constructs of activation and associative priming. The model embodies three predictive constraints: (1) the interference level, which arises from residual memory for old goals; (1) the strengthening constraint, which makes predictions about time to encode a new goal; and (3) the priming constraint, which makes predictions about the role of cues in (...) retrieving pending goals. These constraints are formulated algebraically and tested through simulation of latency and error data from the Tower of Hanoi, a means‐ends puzzle that depends heavily on suspension and resumption of goals. Implications of the model for understanding intention superiority, postcompletion error, and effects of task interruption are discussed. (shrink)

René Descartes proposed an interactive dualism that posits an interaction between the mind of a human being and some of the matter located in his or her brain. Isaac Newton subsequently formulated a physical theory based exclusively on the material/physical part of Descartes’ ontology. Newton’s theory enforced the principle of the causal closure of the physical, and the classical physics that grew out of it enforces this same principle. This classical theory purports to give, in principle, a complete deterministic account (...) of the physically described properties of nature, expressed exclusively in terms of these physically described properties themselves. Orthodox contemporary physical theory violates this principle in two separate ways. First, it injects random elements into the dynamics. Second, it allows, and also requires, abrupt probing actions that disrupt the mechanistically described evolution of the physically described systems. These probing actions are called Process 1 interventions by von Neumann. They are psycho-physical events. Neither the content nor the timing of these events is determined either by any known law, or by the afore-mentioned random elements. Orthodox quantum mechanics considers these events to be instigated by choices made by conscious agents. In von Neumann’s formulation of quantum theory each such intervention acts upon the state of the brain of some conscious agent. Thus orthodox von Neumann contemporary physics posits an interactive dualism similar to that of Descartes. But in this quantum version the effects of the conscious choices upon our brains are controlled, in part, by the known basic rules of quantum physics. This theoretically specified mind-brain connection allows many basic psychological and neuropsychological findings associated with the apparent physical effectiveness of our conscious volitional efforts to be explained in a causal and practically useful way.. (shrink)

Neural Darwinism (ND) is a large scale selectionist theory of brain development and function that has been hypothesized to relate to consciousness. According to ND, consciousness is entailed by reentrant interactions among neuronal populations in the thalamocortical system (the ‘dynamic core’). These interactions, which permit high-order discriminations among possible core states, confer selective advantages on organisms possessing them by linking current perceptual events to a past history of value-dependent learning. Here, we assess the consistency of ND with 16 widely recognized (...) properties of consciousness, both physiological (for example, consciousness is associated with widespread, relatively fast, low amplitude interactions in the thalamocortical system), and phenomenal (for example, consciousness involves the existence of a private flow of events available only to the experiencing subject). While no theory accounts fully for all of these properties at present, we find that ND and its recent extensions fare well. (shrink)

Human vision briefly retains a trace of a stimulus after it disappears. This trace—iconic memory—is often believed to be a surrogate for the original stimulus, a representational structure that can be used as if the original stimulus were still present. To investigate its nature, a flicker-search paradigm was developed that relied upon a full scan (rather than partial report) of its contents. Results show that for visual search it can indeed act as a surrogate, with little cost for alternating between (...) visible and iconic representations. However, the duration over which it can be used depends on the type of task: some tasks can use iconic memory for at least 240 ms, others for only about 190 ms, while others for no more than about 120 ms. The existence of these different limits suggests that iconic memory may have multiple layers, each corresponding to a particular level of the visual hierarchy. In this view, the inability to use a layer of iconic memory may reflect an inability to maintain feedback connections to the corresponding representation. (shrink)

To study conscious experience we must, to some extent, trust introspective reports; yet introspective reports often do not merit our trust. A century ago, E.B. Titchener advocated extensive introspective training as a means of resolving this difficulty. He describes many of his training techniques in his four-volume laboratory manual of 1901- 1905. This paper explores Titchener's laboratory manual with an eye to general questions about the prospects of introspective training for contemporary consciousness studies, with a focus on the following examples: (...) introspective knowledge of the combination tones that arise when a musical interval is played; the 'flight of colours' in the afterimage of a field of bright, broad- spectrum light; and the possibility of non-obvious visual illusions. Introspective training appears to have some merit, but also to involve significant hazards. (shrink)

Explicatures are not cancellable. Theoretical considerations.

This article addresses issues in developing cognitive architectures--generic computational models of cognition. Cognitive architectures are believed to be essential in advancing understanding of the mind, and therefore, developing cognitive architectures is an extremely important enterprise in cognitive science. The article proposes a set of essential desiderata for developing cognitive architectures. It then moves on to discuss in detail some of these desiderata and their associated concepts and ideas relevant to developing better cognitive architectures. It argues for the importance of taking (...) into full consideration these desiderata in developing future architectures that are more cognitively and ecologically realistic. A brief and preliminary evaluation of existing cognitive architectures is attempted on the basis of these ideas. (shrink)

The essays collected in this volume are all concerned with the connection between fiction and truth. This question is of utmost importance to metaphysics, philosophy of language, philosophical logic and epistemology, raising in each of these areas and at their intersections a large number of issues related to creation, existence, reference, identity, modality, belief, assertion, imagination, pretense, etc. All these topics and many more are addressed in this collection, which brings together original essays written from various points of view by (...) philosophers of diverse trends. These essays constitute major contributions to the current debates that the connection between truth and fiction continually enlivens, and give a sense of the directions in which research on this question is heading. Contributors: Fred Adams, Frederick Kroon, Robert Howell, Brendan Murday, Terence Parsons, Graham Priest, Erich Rast, Manuel Rebuschi, Marion Renauld, R.M. Sainsbury, Grant Tavinor, Alberto Voltolini. (shrink)

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)

Attention is a complex process that modulates perception in various ways. Phenomenological philosophy provides an array of concepts for describing the rich structures of attention, thereby avoiding reductions to singular aspects of an experiential spectrum. By suggesting various modes and levels of attentional experience, we intend to do some justice to its complexity, taking into account sub-personal and personal factors on the side of subjective (noetic) horizons and feature-oriented as well as context-oriented aspects on the side of objective (noematic) horizons.

The nature of attention has been the topic of a lively research programme in psychology for over a century. But there is widespread agreement that none of the theories on offer manage to fully capture the nature of attention. Recently, philosophers have become interested in the debate again after a prolonged period of neglect. This paper contributes to the project of explaining the nature of attention. It starts off by critically examining Christopher Mole’s prominent “adverbial” account of attention, which traces (...) the failure of extant psychological theories to their assumption that attending is a kind of process. It then defends an alternative, process-based view of the metaphysics of attention, on which attention is understood as an activity and not, as psychologists seem to implicitly assume, an accomplishment. The entrenched distinction between accomplishments and activities is shown to shed new light on the metaphysics of attention. It also provides a novel diagnosis of the empirical state of play. (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 visual perception 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)

Quantum mechanical theories of consciousness are contrasted to classical ones. A key difference is that the quantum laws are fundamentally psychophysical and provide an explanation of the causal effect of conscious effort on neural processes, while the laws of classical physics, being purely physical, cannot. The quantum approach provides causal explanations, deduced from the laws of physics, of correlations found in psychology and in neuropsychology.

Existentialist accounts maintain that visual phenomenal content takes the logical form of an existentially quantified sentence. These accounts do not make phenomenal content specific enough. Singularist accounts posit a singular content in which the seen object is a constituent. These accounts make phenomenal content too specific. My account gets the specificity of visual phenomenal content just right. My account begins with John Searle's suggestion that visual experience represents an object as seen, moves this relation outside the scope of the existential (...) quantifier and then replaces it with the relation of objects being ‘present as accessible’, as described by Alva Noë. (shrink)

We take self‐governance or autonomy to be a central feature of human agency: we believe that our actions normally occur under our guidance and at our command. A common criticism of the standard theory of action is that it leaves the agent out of his actions and thus mischaracterizes our autonomy. According to proponents of the endorsement model of autonomy, such as Harry Frankfurt and David Velleman, the standard theory simply needs to be supplemented with the agent's actual endorsement of (...) his actions in order to make room for our autonomy. I argue that their proposal fails and that a more substantive enrichment of the standard theory is called for. (shrink)

Scientific concepts are defined by metaphors. These metaphors determine what atten- tion is and what count as adequate explanations of the phenomenon. The authors analyze these metaphors within 3 types of attention theories: (a) --cause-- theories, in which attention is presumed to modulate information processing (e.g., attention as a spotlight; attention as a limited resource); (b) --effect-- theories, in which attention is considered to be a by-product of information processing (e.g., the competition meta- phor); and (c) hybrid theories that combine (...) cause and effect aspects (e.g., biased- competition models). The present analysis reveals the crucial role of metaphors in cognitive psychology, neuroscience, and the efforts of scientists to find a resolution to the classic problem of cause versus effect interpretations. (shrink)

In this work, we evaluate the status of both theory and empirical evidence in the field of experimental rest-break research based on a framework that combines mental-chronometry and psychometric-measurement theory. To this end, we provide a taxonomy of rest breaks according to which empirical studies can be classified. Then, we evaluate the theorizing in both the basic and applied fields of research and explain how popular concepts relate to each other in contemporary theoretical debates. Here, we highlight differences between all (...) these models in the light of two symbolic categories, termed the resource-based and satiation-based model, including aspects related to the dynamics and the control mechanisms at work. Based on a critical assessment of existing methodological and theoretical approaches, we finally provide a set of guidelines for both theory building and future empirical approaches to the experimental study of rest breaks. We conclude that a psychometrically advanced and theoretically focused research of rest and recovery has the potential to finally provide a sound scientific basis to eventually mitigate the adverse effects of ever increasing task demands on performance and well-being in a multitasking world at work and leisure. (shrink)

Quantum approaches to consciousness are sometimes said to be motivated simply by the idea that quantum theory is a mystery and consciousness is a mystery, so perhaps the two are related. That opinion betrays a profound misunderstanding of the nature of quantum mechanics, which consists fundamentally of a pragmatic scientific solution to the problem of the connection between mind and matter.

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)