This paper concerns how motor actions are neurally represented and coded. Action planning and motor preparation can be studied using a specific type of representational activity, motor imagery. A close functional equivalence between motor imagery and motor preparation is suggested by the positive effects of imagining movements on motor learning, the similarity between the neural structures involved, and the similar physiological correlates observed in both imaging and preparing. The content of motor representations can be inferred from motor images at a (...) macroscopic level, based on global aspects of the action (the duration and amount of effort involved) and the motor rules and constraints which predict the spatial path and kinematics of movements. A more microscopic neural account calls for a representation of object-oriented action. Object attributes are processed in different neural pathways depending on the kind of task the subject is performing. During object-oriented action, a pragmatic representation is activated in which object affordances are transformed into specific motor schemas (independently of other tasks such as object recognition). Animal as well as human clinical data implicate the posterior parietal and premotor cortical areas in schema instantiation. A mechanism is proposed that is able to encode the desired goal of the action and is applicable to different levels of representational organization. (shrink)

Examines the theses that the postulation of mental processing is unnecessary to account for our perceptual relationship with the world, see turvey etal. for a criticque.

Ecological psychology is one of the most influential theories of perception in the embodied, anti-representational, and situated cognitive sciences. However, radical enactivists claim that Gibsonians tend to describe ecological information and its ‘pick up’ in ways that make ecological psychology close to representational theories of perception and cognition. Motivated by worries about the tenability of classical views of informational content and its processing, these authors claim that ecological psychology needs to be “RECtified” so as to explicitly resist representational readings. In (...) this paper, we argue against this call for RECtification. To do so, we offer a detailed analysis of the notion of perceptual information and other related notions such as specificity and meaning, as they are presented in the specialized ecological literature. We defend that these notions, if properly understood, remain free of any representational commitment. Ecological psychology, we conclude, does not need to be RECtified. (shrink)

A traditional view of perception and action makestwo assumptions: that the causal flow betweenperception and action is primarily linear or one-way,and that they are merely instrumentally related toeach other, so that each is a means to the other.Either or both of these assumptions can be rejected. Behaviorism rejects the instrumental but not theone-way aspect of the traditional view, thus leavingitself open to charges of verificationism. Ecologicalviews reject the one-way aspect but not theinstrumental aspect of the traditional view, so thatperception and (...) action are seen as instrumentallyinterdependent. It is argued here that a betteralternative is to reject both assumptions, resultingin a two-level interdependence view in whichperception and action co-depend on dynamicallycircular subpersonal relations and as a result may bemore than merely instrumentally interdependent. Thisis illustrated by reference to motor theories ofperception and control theories of action. (shrink)

How do minds emerge from developing brains? According to the representational features of cortex are built from the dynamic interaction between neural growth mechanisms and environmentally derived neural activity. Contrary to popular selectionist models that emphasize regressive mechanisms, the neurobiological evidence suggests that this growth is a progressive increase in the representational properties of cortex. The interaction between the environment and neural growth results in a flexible type of learning: minimizes the need for prespecification in accordance with recent neurobiological evidence (...) that the developing cerebral cortex is largely free of domain-specific structure. Instead, the representational properties of cortex are built by the nature of the problem domain confronting it. This uniquely powerful and general learning strategy undermines the central assumption of classical learnability theory, that the learning properties of a system can be deduced from a fixed computational architecture. Neural constructivism suggests that the evolutionary emergence of neocortex in mammals is a progression toward more flexible representational structures, in contrast to the popular view of cortical evolution as an increase in innate, specialized circuits. Human cortical postnatal development is also more extensive and protracted than generally supposed, suggesting that cortex has evolved so as to maximize the capacity of environmental structure to shape its structure and function through constructive learning. (shrink)

Noam Chomsky and other linguists and psychologists have suggested that human linguistic behavior is somehow governed by a mental representation of a transformational grammar. Challenges to this controversial claim have often been met by invoking an explicitly computational perspective: It makes perfect sense to suppose that a grammar could be represented in the memory of a computational device and that this grammar could govern the device's use of a language. This paper urges, however, that the claim that humans are such (...) a device is unsupported and that it seems unlikely that linguists and psychologists really want to claim any such thing. Evidence for the linguists' original claim is drawn from three main sources: the explanation of language comprehension and other linguistic abilities; evidence for formal properties of the rules of the grammar; and the explanation of language acquisition. It is argued in this paper that none of these sources provides support for the view that the grammar governs language processing in something like the way a program governs the operation of a programmed machine. The computational approach, on the contrary, suggests ways in which linguistic abilities can be explained without the attribution of any explicit representation of rules governing linguistic behavior. (shrink)

I aim to show that perception depends counterfactually on the action we want to perform. Perception is not all-purpose: what we want to do does influence what we see. After clarifying how this claim is different from the one at stake in the cognitive penetrability debate and what counterfactual dependence means in my claim, I will give a two-step argument: one’s perceptual attention depends counterfactually on one’s intention to perform an action and one’s perceptual processing depends counterfactually on one’s perceptual (...) attention. If we put these claims together, what we get is that one’s perceptual processing depends counterfactually on one’s intention to perform an action. (shrink)

Intelligent systems are faced with the problem of securing a principled (ideally, veridical) relationship between the world and its internal representation. I propose a unified approach to visual representation, addressing both the needs of superordinate and basic-level categorization and of identification of specific instances of familiar categories. According to the proposed theory, a shape is represented by its similarity to a number of reference shapes, measured in a high-dimensional space of elementary features. This amounts to embedding the stimulus in a (...) low-dimensional proximal shape space. That space turns out to support representation of distal shape similarities which is veridical in the sense of Shepard's (1968) notion of second-order isomorphism (i.e., correspondence between distal and proximal similarities among shapes, rather than between distal shapes and their proximal representations). Furthermore, a general expression for similarity between two stimuli, based on comparisons to reference shapes, can be used to derive models of perceived similarity ranging from continuous, symmetric, and hierarchical, as in the multidimensional scaling models (Shepard, 1980), to discrete and non-hierarchical, as in the general contrast models (Tversky, 1977; Shepard and Arabie, 1979). (shrink)

I argue that the most promising approach to understanding J.J. Gibson's "affordances" takes affordances themselves as ontological primitives, instead of treating them as dispositional properties of more primitive things, events, surfaces, or substances. These latter are best treated as coalescences of affordances present in the environment (or "coalescences of use-potential," as in Sanders (1994) and Hilditch (1995)). On this view, even the ecological approach's stress on the complementary organism/environment pair is seen as expressing a particular affordance relation between the world (...) and the analyst. That the world is parsed in any way among events and objects, perceivers and worlds, etc., reflects equally features of certain real or possible perspectives on the world and features of the world itself. In section 1, I begin by contending that, contrary to the apparent expectations of some in the field, the bare existence of affordances is surely quite uncontroversial. In section 2, I argue that the most reasonable approach to foundational ontology is a relativistic one. In section 3, I address the claim that affordances must be ontologically complemented by effectivities for the sake of completeness, and I shall argue against that claim on grounds that I take to reflect some of Gibson's most important insights. This work will help to clarify the way affordances are to be used in the fourth and final section, where I argue that ontological work, even within special sciences, should not be merely "regional," and that the most attractive general approach to ontological questions is one that is based on affordances, rather than upon things, events, surfaces, and the like. (shrink)

Behaviour is often described as the computation of a response to a stimulus. This description is incomplete in an important way because it only examines what occurs between the reception of stimulus information and the generation of an action. Behaviour is more correctly described as a control process where actions are performed in order to affect perceptions. This closed-loop nature of behaviour is de-emphasized in modern discussions of brain function, leading to a number of artificial mysteries. A notable example is (...) the ‘symbol grounding problem'. When behaviour is viewed as a control process, it is natural to explain how internal representations, even symbols, can have meaning for an organism, and how actions can be motivated by organic needs. (shrink)

Post-Gibson attempts to set out a definition of affordance generally agree that this notion can be understood as a property of the environment with salience for an organism’s behavior. According to this view, some scholars advocate the idea that affordances are dispositional properties of physical objects that, given suitable circumstances, necessarily actualize related actions. This paper aims at assessing this statement in light of a theory of affordance perception. After years of discontinuity between strands of empirical and theoretical research, the (...) time is ripe for addressing the question of whether the dispositional interpretation of affordance is in accordance with some recent evidence from cognitive science and neuroscience. Following this line, I clarify that there are some cases of affordance-related effects that neither require the actualization of an action, nor the presence of an action-related property bearer in the environment, and that the identification of affordance with physical properties provides only a partial explanation of the wide range of affordance-related effects. Accordingly, I argue in favor of a more general account of affordance perception based on the ability to directly detect perceptual patterns in the environment. (shrink)

Recent discussions in the philosophy of psychology have examined the use and legitimacy of such notions as “representation”, “content”, “computation”, and “inference” within a scientific psychology. While the resulting assessments have varied widely, ranging from outright rejection of some or all of these notions to full vindication of their use, there has been notable agreement on the considerations deemed relevant for making an assessment. The answer to the question of whether the notion of, say, representational content may be admitted into (...) a scientific psychology has often been made to hinge upon whether the notion can be squared with our “ordinary” or “folk” style of psychological explanation, with its alleged commitment to the idiom of beliefs and desires. In this article, I proceed the other way around, starting with experimental psychology itself and asking whether such notions as the above play a legitimate role within a particular area of contemporary theory, the psychology of perception. My conclusion will be that especially the first three have a legitimate place in theories of perception, albeit one that differs from that ascribed to them in a significant portion of the philosophical literature. Along the way I develop a notion of noncognitive functional analysis, which separates the notion of contentful perceptual processing and perceptual representation from cognitive or conceptual content. (This paper has been reprinted, with stylistic revisions, in Perception and Cognition, Essays in the Philosophy of Psychology, Oxford, Clarendon Press, 2009, pp. 50-87.). (shrink)

This paper argues that an ecological approach to psychology of the sort advanced by J. J. Gibson provides a coherent and powerful alternative to the computational, information-processing, paradigm. The paper argues for two principles. Firstly, one cannot begin to understand what internal information processing an organism must accomplish until one understands what information is available to the organism in its environment. Secondly, an organism can process information by acting on or manipulating physical structures in its environment. An attempt is made (...) to show how these principles can be extended to cognition as a whole. It is suggested that these principles may have a foundation in evolutionary biology. (shrink)

The following paper presents a characterization of three distinctions fundamental to computationalism, viz., the distinction between analog and digital machines, representation and nonrepresentation-using systems, and direct and indirect perceptual processes. Each distinction is shown to rest on nothing more than the methodological principles which justify the explanatory framework of the special sciences.

The resent paper reviews three phases in the literature on cognition and colour, and also Luria's (1976) observations of the effects that literacy and/or schooling have on colour naming and colour categorization. It is argued that Luria's own interpretation of his findings is partiafly flawed by inconsistency, and by ethnocentric presuppositions concerning mediation and abstraction. A revised interpretation is proposed that draws on Gibson's (1950, 1966) contrast between direct and indirect perceptions. It is suggested that language usage and cultural practices (...) come to exert a joint effect upon the experience of colour by selectively directing attention towards or away from the various perceptible aspects of coloured objects. (shrink)

In this paper we suggest that differing approaches to the science of social cognition mirror the arguments between radical embodied and traditional approaches to cognition. We contrast the use in social cognition of theoretical inference and mental simulation mechanisms with approaches emphasizing a direct perception of others’ mental states. We build from a recent integrative framework unifying these divergent perspectives through the use of dual-process theory and supporting social neuroscience research. Our elaboration considers two complementary notions of direct perception: one (...) primarily stemming from ecological psychology and the other from enactive cognition theory. We use this as the foundation from which to offer an account of the informational basis for social information and assert a set of research propositions to further the science of social cognition. In doing so, we point out how perception of the minds of others can be supported in some cases by lawful information, supporting direct perception of social affordances and perhaps, mental states, and in other cases by cues that support indirect perceptual inference. Our goal is to extend accounts of social cognition by integrating advances across disciplines to provide a multi-level and multi-theoretic description that can advance this field and offer a means through which to reconcile radical embodied and traditional approaches to cognitive neuroscience. (shrink)

Jeannerod's target article describes support, through empirical and neurological findings, for the intriguing idea of motor imagery, a form of representation hypothesized to have levels of functional equivalence with motor preparation, while being consciously accessible. Jeannerod suggests that the subjectively accessible content of motor imagery allows it to be distinguished from motor preparation, which is unconscious. Motor imagery is distinguished from visual imagery in terms of content. Motor images are kinesthetic in nature; they are parametrized by variables such as force (...) and time and they are potentially governed by kinematic rules. Jeannerod acknowledges, however, that motor and visual imagery may not easily be separated, because actions take place in a spatial environment. I agree; in fact, I suggest here that visualization may generally be concomitant with, and may even subjectively dominate, motor imagery. (shrink)

This paper re-addresses Quine's indeterminacy of translation/inscrutability of reference thesis, as a problem for cognitive theories of content. In contradistinction with Quine's behavioristic semantics, theories of meaning, or content, in the cognitivist tradition endorse intentional realism, and are prone to be unsympathetic to Quine's thesis. Yet, despite this fundamental difference, I argue that they are just as vulnerable to the indeterminacy. I then argue that the vulnerability is rooted in a theoretical commitment tacitly shared with Quine, namely, the commitment to (...) the view that the perceptual input to the cognitive system is extensional - differentiating objects, but not the aspects (or, properties) they manifest. Thus, input extensionalism, and not behaviorism, is what forces the indeterminacy. I conclude by suggesting that the solution to Quine's indeterminacy problem hinges on the elaboration of an intensional theory of perceptual input, and of content in general. (shrink)

The strategies of action employed by a human subject in order to perceive simple 2-D forms on the basis of tactile sensory feedback have been modelled by an explicit computer algorithm. The modelling process has been constrained and informed by the capacity of human subjects both to consciously describe their own strategies, and to apply explicit strategies; thus, the strategies effectively employed by the human subject have been influenced by the modelling process itself. On this basis, good qualitative and semi-quantitative (...) agreement has been achieved between the trajectories produced by a human subject, and the traces produced by a computer algorithm. The advantage of this reciprocal modelling option, besides facilitating agreement between the algorithm and the empirically observed trajectories, is that the theoretical model provides an explanation, and not just a description, of the active perception of the human subject. (shrink)

According to the traditional inferential theory of perception, percepts of object motion or stationarity stem from an evaluation of afferent retinal signals (which encode image motion) with the help of extraretinal signals (which encode eye movements). According to direct perception theory, on the other hand, the percepts derive from retinally conveyed information only. Neither view is compatible with a perceptual phenomenon that occurs during visually induced sensations of ego motion (vection). A modified version of inferential theory yields a model in (...) which the concept of extraretinal signals is replaced by that of reference signals, which do not encode how the eyes move in their orbits but how they move in space. Hence reference signals are produced not only during eye movements but also during ego motion (i.e., in response to vestibular stimulation and to retinal image flow, which may induce vection). The present theory describes the interface between self-motion and object-motion percepts. An experimental paradigm that allows quantitative measurement of the magnitude and gain of reference signals and the size of the just noticeable difference (JND) between retinal and reference signals reveals that the distinction between direct and inferential theories largely depends on: (1) a mistaken belief that perceptual veridicality is evidence that extraretinal information is not involved, and (2) a failure to distinguish between (the perception of) absolute object motion in space and relative motion of objects with respect to each other. The model corrects these errors, and provides a new, unified framework for interpreting many phenomena in the field of motion perception. (shrink)