Visual illusions and direct perception: Elaborating on Gibson's insights

Gibson argued that illusory pictorial displays contain “inadequate” information (1966, p. 288) but also that a “very special kind of selective attention” (p. 313) can dispel the illusion–suggesting that adequate perceptual information could in fact be potentially available to observers. The present paper describes Gibson's treatment of geometrical illusions and reviews pertinent empirical evidence. Interestingly, Gibson's insights have been corroborated by recent findings of inter- and intra-observer variability in susceptibility to visual illusions as a function of culture, learning and task. It is argued that these findings require a modification of the general Gibsonian principle of perception as the detection of specifying information. Withagen and Chemero's (2009) evolutionary motivated reconceptualization of perception predicts observers' use of both specifying and non-specifying information and inter- and intra-observer variability therein. Based on this reconceptualization we develop an ecological approach to visual illusions that explains differential illusion effects in terms of the optical variable(s) detected.     

Guiding Movement by Coupling Taus

Studies of sensory guidance of movement in animals show that large nervous systems are not necessary for accurate control, suggesting that guidance may be based on some simple principles. In search for those principles, a theory of guidance of movement is described, which has its roots in Gibson's pathfinding work on visual control of locomotion (J. J. Gibson, 1958/this issue). The theory is based on the use of the simple but powerful variable tau, the time-to-closure of a gap at the current gap closure rate (whatever the gap's dimension—distance, angle, force, etc.); and on the principle of tau-coupling (keeping two Ts in constant ratio). In this article, I show how tau-coupling could be used to synchronize movements and regulate their kinematics. Supportive experimental results are reported. I also show theoretically how sensory-taus, defined on sensory input arrays, can specify motion-taus through tau-coupling; how the braking procedure of keeping tau.dot stable is a particular case of tau.coupling; and how tools for steering (e.g., limbs, whole bodies, cars, or aircraft) could be built from tau-couplings, which would enable steering control in a variety of situations, including steering straight and curved courses to goals, steering and controlling speed at the same time, steering around obstacles, and asymptoting on surfaces as when landing. Some movements also involve intrinsic guidance from within, and a hypothesis on intrinsic guidance by tau is introduced, supported by experiments spanning different activities.     

A Systems Approach to Perception and Action

ABSTRACT

On the 50th anniversary of its publication, we look back on some of the intellectual contributions of Gibson's (1966) The Senses Considered as Perceptual Systems. This work is often seen as contributing a new perspective to our understanding of the 5 senses. In this paper, we explore another intellectual contribution: Gibson's treatment of perception–action as an irreducible, functional system. We review select examples of systems thinking from the physical, animal, and human social domains. Our suggestion is that a systems-level approach to social interactions would have been a natural extension of Gibson's ideas.     

Visually Controlled Locomotion: Its Dependence on Optic Flow,Three-Dimensional Space Perception,and Cognition

Gibson (1958/this issue) and his followers have emphasized the role of optic flow in the control of locomotion. In recent years much research has been devoted to the visual control of aiming and braking, mainly in connection with terrestrial locomotion. The goal of this article is to broaden the topic empirically and theoretically. At the empirical level, we argue that there are a number of visually controlled maneuvers that need to be addressed for their own sake, for they involve more than can be learned from research on aiming and braking. At the theoretical level, we argue that optic flow needs to be supplemented by other explanatory primitives, including the actor's perception of three-dimensional spatial layout and the actor's cognitive representations of the spatial envelope and plant dynamics of his or her body or vehicle.     

The topological approach to perceptual organization

To address the fundamental question of “what are the primitives of visual perception”, a theory of topological structure and functional hierarchy in visual perception has been proposed. This holds that the global nature of perceptual organization can be described in terms of topological invariants, global topological perception is prior to the perception of other featural properties, and the primitives of visual form perception are geometric invariants at different levels of structural stability. In Part I of this paper, I will illustrate why and how the topological approach to perceptual organization has been advanced. In Part II, I will provide empirical evidence supporting the early topological perception, while answering some commonly considered counteraccounts. In Part III, to complete the theory, I will apply the mathematics of tolerance spaces to describe global properties in discrete sets. In Part IV, I will further present experimental data to demonstrate the global-to-local functional hierarchy in form perception, which is stratified with respect to structural stability defined by Klein's Erlangen Program. Finally, in Part V, I will discuss relations of the global-to-local topological model to other theories: The topological approach reformulates both classical Gestalt holism and Gibson's direct perception of invariance, while providing a challenge to computational approaches to vision based on the local-to-global assumption.     

The Ecological Revolution: The Senses Considered as Perceptual Systems, 50 Years Later - Part 2

ABSTRACT

This editorial presents the second of a 2-part special issue honoring the publication of James J. Gibson's 1966 book, The Senses Considered as Perceptual Systems. As was pointed out by several reviews of this book written just after its publication (i.e., between 1967 and 1969), Gibson's 1966 book represents a revolution not only for the psychological science but also for domains beyond that of psychology. This second part of the special issue is composed of 5 theoretical contributions that represent, in addition to the 4 pieces previously published in the first part, the far-reaching influence of Gibson's ecological revolution.     

Discussion: The Roots of Emerging Ecological Psychology

I briefly trace the topics presented in the 4 symposium papers in a cyclic order. Sheena Rogers' (this issue) paper discussing an example of J. J. Gibson's sense of 'information' (the horizon ratio) and Eleanor J. Gibson's (this issue) paper discussing affordance learning bring together the 2 core concepts of ecological psychology (information and affordance). Robert Lickliter (this issue) and Gene C. Goldfield (this issue), along with E. J. Gibson, discuss skill development in context utilizing comparative psychology and human infant research. For the recent history that holds these topics together, the early contributions of E. B. Holt and J. J. Gibson are emphasized.     

1966 and All That: James Gibson and Bottom-Down Theory

ABSTRACT

The “later” James Gibson is widely misrepresented as an extreme stimulus–response theorist. In fact, Gibson's 1966 book presents a radical alternative to stimulus–response theory. “Perceptual systems” are not passive and receptive but “organs of active attention” (1966/1968, p. 58). Perceivers “reach out” into the world. This commentary examines some of the implications of Gibson's systems-cum-functionalist-cum-ecological approach, including the relations between the senses; the concept of “sensationless” perception; and most fundamentally, the nature of perceptual systems as extending beyond the body. I conclude that an adequate understanding of perception cannot be limited to the already severely limited domain of psychology. If Gibson is right, “ecological psychology” is a contradiction in terms.     

Origins of Self-Perception in Infancy

Most accounts of the origins of the self-concept in humans rely on the mirror self-recognition (rouge removal) task whereby the infant is credited with self-awareness at about 15 months, once it is able to use the mirror reflection to locate a dab of rouge on the nose. But mirror self- recognition may require relatively advanced cognitive abilities and may reveal relatively little about the ontogenetic origins of self-knowledge. The aim of this article is to consider the antecedents of self-knowledge in processes of sensory perception during infancy. J. J. Gibson' s ecological approach to sensory perception asserts that there is information for the distinction between self and nonself inherent in perception. Evidence from human infants who are too young to recognize themselves in mirrors is reviewed for a sensory perceptual basis for the existential self (the I) and for the categorical self (the me) in William James' s terminology. Studies of the visual proprioceptive control of posture in babies may be interpreted to support an inherent distinction between self and nonself in infantperception, rather than the traditional account of an "adualistic confusion." Similarly, various aspects of bodily self-awareness manifested even by fetuses demonstrate some basis for a categorical self as an original aspect of experience. Self-specification in perception is also indicated in recent research on imitation in very young infants, a possible mechanism for the essentially social component of self-concept development. Although a case for early self-specification in perception can readily be made, it is much more difficult to explain how self-perception gives rise to self-conception. One possibility briefly discussed is that a process of representation and re-representation of information originally obtained through interaction with physical and social objects gives rise to reflective self- awareness and the particularly autobiographical knowledge of self which we take to be species- typical of humans.     

The Senses Considered as One Perceptual System

ABSTRACT

J. J. Gibson (1966) rejected many classical assumptions about perception but retained 1 that dates back to classical antiquity: the assumption of separate senses. We suggest that Gibson's retention of this assumption compromised his novel concept of perceptual systems. We argue that lawful, 1:1 specification of the animal–environment interaction, which is necessary for perception to be direct, cannot exist in individual forms of ambient energy, such as light, or sound. We argue that specification exists exclusively in emergent, higher order patterns that extend across different forms of ambient energy. These emergent, higher order patterns constitute the global array. If specification exists exclusively in the global array, then direct perception cannot be based upon detection of patterns that are confined to individual forms of ambient energy and, therefore, Gibson's argument for the existence of several distinct perceptual systems cannot be correct. We argue that the senses function as a single, irreducible perceptual system that is sensitive exclusively to patterns in the global array. That is, rather than distinct perceptual systems there exists only 1 perceptual system.     

Invariants and Information Pickup in The Senses Considered as Perceptual Systems: Implications for the Experimental Analysis of Behavior

ABSTRACT

Although Gibson focused his agenda on the study of perception and Skinner on learning as contingencies of reinforcement, they shared a nonrepresentational approach. We propose that the ecological concept of invariants developed in Gibson's book The Senses Considered as Perceptual Systems (1966) could underlie Skinner's notion of contingencies of reinforcement as environmental opportunities for behaving. The proposal is divided in 3 parts: the concept of stimulus for perception, the role of the notion of invariants in the operant contingency, and the information for perception and behavior. We conclude that approximating contingencies of reinforcement as instances of environmental invariants can be fruitful for studying a number of phenomena within the context of operant conditioning.     

What Is an Affordance?

What should and should not be considered an affordance is still an open issue. At the 2002 North American meeting of the International Society for Ecological Psychology, a symposium was held concerning this topic. The articles in this special issue are expanded versions of the papers presented at that symposium. To set the stage for those discussions, this article presents an analysis of the evolution of J. J. Gibson's thinking on this issue, from some of his earliest writings (i.e., J. J. Gibson & Crooks, 1938) through his most recent writings (i.e., J. J. Gibson, 1979/1986). It is hoped that this forum will stimulate thinking concerning this important ecological concept.     

Christ in the Limelight: Contemporary Films and Christological Discourse

The aim of this article is to show how theology can, through the medium of film, engage contemporary interpretations of Jesus’ person and work. Starting out by tracing the development taking place in films about Jesus throughout the twentieth century, the focus then moves to a theological reading of Mel Gibson's interpretation of the passion story for the twenty‐first century in his movie The Passion of the Christ.     

Practical Perception and Intelligent Action

Perceiving things to be a certain way may in some cases lead directly to action that is intelligent (e.g., skillful, wise, clever, astute). This phenomenon has not often been discussed, though it is of broad philosophical interest. It also raises a difficult question: how can perception produce intelligent action? After clarifying the question—which I call the question of “practical perception”—and explaining what is required for an adequate answer, I critically examine two candidate answers drawn from work on related topics: the first, inspired by Hubert Dreyfus's phenomenological analysis of absorbed coping (and of a piece with James Gibson's theory of affordances), focuses on awareness of situational features; the other, suggested by Gilbert Ryle's classic treatment of knowledge‐how, focuses on possession of behavioral dispositions. I argue that neither approach is adequate. Subsequently, I develop and defend an alternative answer that emphasizes the agent's conceptual understanding.     

An Ecological Approach to Reducing the Social Isolation of People With an Intellectual Disability

An ecological approach to understanding insecure attachments and social isolation among people with an intellectual disability is constructed using Gibson's (1979/1986) affordance-based theory. Although environmental affordances and individual limitations interact to limit the development of social competence, we believe that by focusing on the immediate environment, community-based approaches to helping people with an intellectual disability are often ignored, which increases the burden on individual caregivers. A more comprehensive strategy, which extends Gibson's theory of affordances, allows us to consider how higher level social systems influence the immediate environment and provides the context for understanding why successful change occurs when a multifaceted, holistic approach that works on several levels is adopted. Examining these systems within an ecological framework fundamentally redefines our thinking by shifting the focus from a person's disability to a more nuanced understanding of a person's abilities within the context of appropriate environmental supports in which the person's disability becomes less salient.     

Evidence for Direct Perception From Cognition in the Wild

This article describes a portion of a study of cognition in the wild that was conducted to investigate how human operators of nuclear power plants monitor the state of the plant to detect abnormalities. Although the study was originally motivated by applied concerns, it surprisingly led to evidence relevant to basic theories of perception. The findings reveal that the instruments in the control room that operators can use for monitoring are both fallible and limited in their informativeness, thereby occasionally providing an inaccurate indication of plant status. As a result, operators sometimes leave the control room to directly observe components in the plant using their unaided perceptual systems. Because such information is lawfully constrained and not mediated by instruments, it provides a rich, reliable, and therefore, unique and highly valued indication of the true status of the environment. These findings show that Gibson's (1979/1986) distinction between directed and mediated perception is both pragmatically and psychologically relevant. The results also have very important implications for experiments on direct perception based on computer-simulated, rather than lawfully constrained, experimental stimuli.     

Computational Cognitive Neuroscience of the Visual System

ABSTRACT— Should psychologists care about functional magnetic resonance imaging (fMRI)? Within the field of visual perception, the answer to this question is an emphatic "yes." There is a long history of close interactions between psychology and neuroscience in the study of vision. In the 1980s, vision researchers developed a general framework for combining the two fields, and that framework still supports much current research. This article will briefly cover this general approach and then will illustrate how neuroimaging allows the framework to be applied to human perception. In short, fMRI can measure how information is represented in sequential stages of processing. These same representations can also be measured behaviorally. Theories of vision specify how the sequential representations participate in well-defined computations that underlie perception.     

The Need for an Encyclopedia of Psychological Information

The relationship was examined between judgments of relative distance and judgments of relative size made over a surface on which the packing density of the texture elements was progressively increased, from one end of the surface to the other along the S's line of sight. Significant positive correlations were obtained between distance and size judgments made by 32 Ss. This confirmed a weak version of the size-distance invariance hypothesis and supported a prediction contained in Gibson's theory of space perception.     

The dramaturgic perspective: Implications for the study of person perception

The major theoretical contributions to the study of attribution, those of Heider (1958), Kelley (1967) and Jones and Davis (1965) have worked from the assumption that person perception is analogous to object perception and scientific investigation. Goffman's dramaturgic analysis of the social self provides an alternative framework for addressing the problem of how we perceive and understand the behaviour of others. In this paper, I explore the implications of the dramaturgic perspective for the study of person perception and discuss the ways in which it diverges from the traditional approach to attribution. In addition, I present an alternative account of the Fundamental Attributional Error that arises in light of Goffman's dramaturgic analysis.