Eleanor J. Gibson

Development of knowledge of visual-tactual affordances of substance

Infants of 12 months were familiarized in the dark with an object of either a hard or an elastic (spongy) substance. Following 60 sec of manipulation, a visual preference test was given with simultaneous presentation of 2 films of identical objects, 1 moving in a pattern characteristic of a rigid object and 1 moving in a pattern characteristic of an elastic object. Infants handled the 2 substances differently in an appropriate manner and looked preferentially with more and longer first looks to the type of substance familiarized. A replication of this experiment with familiarization in the light yielded comparable results. A third experiment with 1-month-old infants allowed them to mouth objects of either a hard or a soft substance for haptic familiarization and then tested looking preferences with real objects moving rigidly or deforming. These infants looked longer at the object moving in a manner characteristic of the novel substance. The results, together, suggest that quite young infants detect intermodal invariants specifying some substances and perceive the affordance of the substance.

Detection of the traversability of surfaces by crawling and walking infants.

In four studies we investigated the perception of the affordance for traversal of a supporting surface. The surface presented was either rigid or deformable, and this property was specified either optically, haptically, or both. In Experiment 1A, crawling and walking infants were presented with two surfaces in succession: a standard surface that both looked and felt rigid and a deforming surface that both looked and felt nonrigid. Latency to initiate locomotion, duration of visual and haptic exploration, and displacement activity were coded from videotapes. Compared with the standard, the deforming surface elicited longer latency, more exploratory behavior, and more displacement in walkers, but not in crawlers, suggesting that typical mode of locomotion influences perceived traversability. These findings were replicated in Experiment 1B, in which the infant was presented with a dual walkway, forcing a choice between the two surfaces. Experiments 2, 3A and B, and 4A and B investigated the use of optical and haptic information in detecting traversability of rigid and nonrigid surfaces. Patterns of exploration varied with the information presented and differed for crawlers and walkers in the case of a deformable surface, as an affordance theory would predict.

Perceptual Learning in Development: Some Basic Concepts

The reciprocity of organism and environment and the reciprocity of perception and action are both reflected in the concept of affordance. Perceiving an affordance entails detecting the relation between the organism’s power of control and some offering of the environment (i.e., perceiving that that resource or support for action has utility for this person, child, or animal). Such a relation (often referred to as an organism–environment fit) is seldom perceived automatically. We learn to perceive affordances of events, objects, and places (layouts) in the course of development. For example, a child may learn that a slope of more than 10° cannot be safely descended upright and on foot but can be negotiated by sitting and sliding. Such learning can be referred to as discovering meaning and is perceived accordingly. Perceptual learning is equally the means of discovering distinctive features and invariant properties of things and events (E. J. Gibson, 1969). Learning to distinguish faces from one another or to distinguish letters of the alphabet are such cases. Discovering a repeated theme in a symphony and the variations on it is another. Discovering distinctiveness and invariance is another kind of meaning, also a product of perceptual learning. ECOLOGICAL PSYCHOLOGY, 12(4), 295–302 Copyright

Where Is the Information for Affordances

Two questions have priority for a perception psychologist: What is perceived, and what is the information for it? What we perceive are the affordances of the world. Because perception is prospective and goes on over time, the information for affordances is in events, both external and within the perceiver. Hence, we must study perception of events if we would understand how affordances are perceived.

The World Is So Full of a Number of Things: On Specification and Perceptual Learning

Two basic concepts of James Gibsons ecological theory of perception are information and affordance. Discovering the information that specifies an affordance is a task confronting all of us and is an essential process in development. Information in the world is manifold and must be narrowed down to perceive what specifies an affordance. Perceptual learning is the process that we study to understand how this comes about.

What Psychology Is About: Ruminations of an Opinionated Aged Psychologist

Psychology is about behavior. That is my firm, well-considered opinion. I believe that psychology should and can be a science, a branch of biology that includes all animals and can be studied from a Darwinian approach as well as an objective experimental one. There must be observables that can be counted, if it is to be a science (and there are). There must be living functions that can be served, if it is to be a branch of biology (and there are). There must be a relationship between those functions and the environment that is inhabited, if we ground it in a Darwinian approach (and there is). Behavior takes place in the world, changes the world, and makes it possible for an organism to use what the world affords. How does one get to this position? We were all taught that psychology was born in philosophy and took its concepts from metaphysics. But it is no longer the study of mind. It has come a long way. Consider some leaps along the way. A century or two ago, the radical notion was proposed that psychology should be modeled after physics. Structure was the focus of research, and the method to be followed was analysis into parts (particles) as the physicists do. Reductionism was the goal, theprinciple tobe followed.Psychologistsbravely looked formental “structure” and reduced mind into parts, such as sensations. German psychologists, notably Wundt, were early exponents of this view, followed by such keen exponents as Titchener. Boring (1933) declared in his book, The Physical Dimensions of Consciousness, that “thorough knowledge of sensations” constituted all of psychology. In a sense, the structuralists have been betrayed by the physicists, who changed key as the theory of relativity came in. As for today: