Gibson, Eleanor Jack

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GIBSON, ELEANOR JACK

(b. Peoria, Illinois, 7 December 1910; d. Columbia, South Carolina, 30 December 2002),

psychology, perceptual learning and development.

Gibson was one of the most prominent experimental psychologists of the twentieth century, contributing profound conceptual and empirical insights about the nature and development of perception and action. Her theory of perceptual learning, including the ideas that differentiation is an essential form of learning and that learning brings about changes in what is perceived, led to new understanding of perceptual development in human infants and children and of basic processes in reading. She was elected to the National Academy of Sciences, and, in 1992, was awarded the National Medal of Science, the highest scientific honor in the United States.

The Early Years . Eleanor Grier Jack received her bachelor’s degree from Smith College, a well-known women’s college, in 1931. She described Smith as “a place where women were not only permitted but encouraged to be scholars, even scientists” (Gibson, 1980, p. 240). Kurt Koffka, the famous Gestalt psychologist, was a member of the faculty, but a far more profound influence on her was that of James J. Gibson who became a junior faculty member as she became a psychology major. Their marriage in 1932 marked the formal beginning of a close personal and intellectual colleagueship that continued until his death in 1979.

After obtaining her master’s degree from Smith (1933), Gibson (known to her colleagues and friends as “Jackie”) went to Yale intending to pursue a PhD studying animal behavior with Robert Yerkes. However, at their first meeting Yerkes informed her that he did not permit women to work in his laboratory. Manifesting a different attitude, Clark Hull, a renowned S-R (stimulus–response) learning theory psychologist, welcomed her as an advisee. She completed her dissertation under his direction on principles of conditioning applied to verbal learning. Gibson first began to clarify the concepts of generalization and especially differentiation, fundamental in all of her subsequent work, in her dissertation. She worked out a detailed theoretical analysis of how generalization and differentiation might influence performance in traditional paired associate learning tasks. This was followed by a systematic series of experiments testing multiple specific hypotheses from that theoretical analysis (Gibson, 1939; 1940; 1941; 1942). The elegance of this programmatic research, with rigorous empirical work closely tied to the theoretical analyses from which it derived, characterized her science throughout her career.

Even before completing her dissertation, Gibson returned to Smith College and full-time teaching. The Gibsons’ first child, a son, was born in 1940, and their daughter was born in 1943. World War II interrupted the Gibsons’ academic careers: They spent the war years in Texas and California, where James Gibson conducted research on aircraft recognition and space perception for the Army Air Forces Aviation Psychology Program. After the war, they returned to Smith and both resumed their academic lives, but in 1949 they moved to Cornell University, where they remained for the rest of their careers.

The Cornell Years and the Study of Perceptual Learning . Cornell, unlike Smith, had a nepotism rule that precluded close relatives from serving on the faculty. Thus Eleanor Gibson was given the title research associate, a small office, and the obligation to support herself and her research as best she could. She found a way to act on her conviction of the importance of a comparative approach to understanding learning and development, a conviction that had taken her to Yale in the first place. She began to study conditioning and maternal-infant interaction with a new species, young goats. In the course of this work she made an observation that foreshadowed some of her most well known subsequent research. Newborn kids, genetically related to mountain dwellers but never having experienced a drop-off, would stand motionless on a small platform several feet above the ground. Students of psychology the world over now learn about the elegant systematic “visual cliff” studies of the sensitivity of the young of many species to information concerning a drop-off.

Gibson and Richard Walk, a faculty colleague at Cornell, devised an apparatus for studying the development of depth discrimination, a visual (or virtual) cliff. The apparatus consisted of a rectangular sheet of glass supported parallel to the floor and some distance above it. A textured pattern is fixed directly to the underside of one-half of the glass (the “near” or “shallow” side of the cliff), and the same textured pattern covers the floor below visible through the other half of the glass (the “far” or “deep” side of the cliff). A slightly raised platform bisects the glass, separating the two sides of the cliff. An animal, or a young human, is placed on the platform and its exploratory behavior and descent to one side or the other of the cliff are observed. Using this simple situation, Gibson and Walk studied depth discrimination in a variety of species and found that, for the most part, animals and humans discriminate the optically deep drop-off from the shallow one at least by the time they can locomote (Walk and Gibson, 1961). For example, human infants who are crawling will readily cross the shallow side to reach their parents who are holding out an attractive toy. The same infants, when encouraged in the same way by their parents to crawl over the deep side, rarely will do so, despite the fact that their tactile contact with the glass surface provides information that it is a suitable surface of support for locomotion.

An important feature of the visual cliff situation is that it uses a natural response of the creatures being observed—that is, locomoting over surfaces. The use of naturally occurring behaviors, for example exploratory behaviors, to study the development of perception characterized most of Gibson’s research, especially her research with human infants.

The visual cliff studies followed a series of experiments on the effects of early experience on rats’ discrimination of two-dimensional shapes. In these experiments rats were raised with geometric forms hanging on the sides of their cages, and their subsequent discrimination of similar forms was assessed (Gibson and Walk, 1956). The question of interest was whether perceptual learning would occur without differential reinforcement of particular responses.

This is the same question that Gibson first began to investigate in her dissertation experiments in the context of verbal learning. Previous theorists had argued that improvement in perceptual discrimination is brought about by the reinforced learning of some kind of responses attached to the items to be discriminated. This is a kind of “enrichment” process that renders the items more distinctive than they once were. Gibson argued that to associate or attach new responses to two similar items logically requires that the items must be distinguishable in the first place. Gibson and her husband published an important paper titled “Perceptual Learning: Differentiation or Enrichment?” in which they articulated a “specificity” theory of the nature of perceptual learning (1955). Departing radically from then-current theories of perceptual learning, they argued that the information available to the sensory systems to support perceiving is rich, and fully specifies its sources in the environment. Perceptual learning involves improvement in discrimination rather than association or inference-making. Through such learning, perception changes, becoming into ever-closer correspondence with the environment. There are many examples of such learning by adults, such as skilled wine tasters, birders, and interpreters of radiological images (such as x-rays and scans). This kind of learning is especially important in understanding development as children, in the normal course of growing up, increasingly distinguish among the features of the worlds in which they function.

During the early 1960s Gibson’s research was concentrated on perceptual development and learning in the context of children’s acquisition of reading skill. Her empirical investigations ranged from questions about the processes of learning to discriminate among letters to questions about extracting the structure of the written language. The focus of this work was on development: how perception develops during childhood, what perceptual learning is, and how it comes about. During this period she wrote a monograph, Principles of Perceptual Learning and Development (1969), in which she presented extant theories of perceptual learning, organized the very large experimental literature on perceptual learning and development, and first laid out in detail her own new theory of perceptual development.

The theory was summarized in terms of three trends in perceptual development. The first is a trend toward increasing specificity of discrimination. Perceptual learning involves a gradual, progressive increase in the specificity of discrimination to what she then called “stimulus information.” Perceiving becomes in closer correspondence to the properties of things and events in the world.

The second trend she described as the optimization of attention. This trend refers to changes in the nature of the exploratory activity that underlies perceptual learning. Such activity becomes more active and more systematic and less captured by the immediate features of the objects of perception. The third trend is toward an increasing economy of perceiving, including processing of larger units of stimulus structure—so-called higher order structure.

After more research on reading, she wrote another book with her research colleague Harry Levin, The Psychology of Reading(1975). In this book they elaborated and extended the principles of perceptual learning to include processes of children’s progression toward becoming skilled readers.

A Laboratory of her Own . Sixteen years after she arrived at Cornell and after she had begun to receive many academic and professional honors, Gibson was appointed a full professor, and shortly thereafter was awarded an endowed professorship. She now had her own laboratory, the Eleanor J. Gibson Laboratory of Developmental Psychology, and she turned to new questions about the development of perception during infancy.

She began to investigate the development of perception of invariants during infancy. For example, using habituation methods, she discovered that young infants detect invariant information for the rigidity or elasticity of moving objects. It had been found that repeated viewing of a display (habituation) changes infants’ preference for looking at that display. Gibson presented repeatedly to infants an object undergoing three rigid motions: rotation in a frontal plane, rotation around the vertical axis, and rotation around the horizontal axis. Then, the infants would be shown an object undergoing a fourth rigid motion, displacement to and fro on the Z axis (so-called looming), as well as the object undergoing a deforming motion. The infants would generalize habituation to the object in rigid motion, and visually discriminate between it and the deforming apparently elastic object (Gibson, Owsley, and Johnston, 1978).

The research on the development of the perception of invariants led quite directly to new research on the development of the perception of affordances in young infants. The concept of affordances was introduced widely in James Gibson’s last book, The Ecological Approach to Visual Perception (1979)—published shortly before his death—although the concept had been evolving for many years. Affordances are features of the world that provide possibilities for action for creatures with specific capabilities. Eleanor Gibson’s first paper on the implications of the affordance concept for a theory of development was titled “The Concept of Affordances in Development: The Renascence of Functionalism” (1982) and the title captures well her point of view. It is first of all a functional view, emphasizing the relation of the perceiver and the environment. For example, she argued that perceptual development and motor development, or the development of action systems, are bound up together. This view is reflected in a conceptual analysis of the development of mobility in infants and young children (Gibson and Schmuckler, 1989).

In that analysis Gibson suggested that three essential components in a child’s mobility are guiding or steering their movement, choosing a traversable surface for locomotion, and maintaining balance (when walking). She and her students investigated all three of these components. Illustrative of the research on surface traversibility was a series of experiments in which infants (about eleven months of age) and toddlers (about fourteen months of age) were presented with two surfaces over which they might locomote (Gibson, Riccio, Schmuckler, et al., 1987). One was a rigid surface and the second was a waterbed surface covered in the same pattern as the first. The infants were all locomoting by crawling and the toddlers were all walking. The question of interest was whether the children would differentiate the two surfaces of support in relation to their own locomotion capabilities. Encouraged by their mothers, the toddlers readily locomoted over the rigid surface but not over the waterbed surface. If they did cross the latter surface, they crawled over it. The younger, crawling infants readily locomoted over both surfaces to reach their mothers. Thus, the children detected the affordances of the surfaces for supporting locomotion relative to their own mode of locomotion.

In addition to stressing the functional nature of the perceiver and the environment, Gibson’s view of perceptual development stressed the importance of exploratory activity in learning about affordances. Babies as young as one month were found to acquire information about objects’ substances by exploring them in their mouths (Gibson and Walker, 1984). In this experiment, the infants’ mothers encouraged them to mouth either a hard object or a spongy object. They inserted the objects in the babies’ mouths in such a way as to conceal the objects from the babies’ view. After a period of mouthing, the objects were removed and the babies watched a rigid object in motion and a spongy object in motion. The babies showed preferential looking (i.e., looked longer) to the object of novel substance—that is, a different substance than the object they had mouthed. Thus, what they had learned about the objects’ substances by mouthing them was reflected in their preferential looking. This learning by exploring is similar to the learning demonstrated by the older babies described above who learned about objects’ substances by watching them move in ways that specified their rigidity or elasticity. Moreover, in this case the infants demonstrated a rather remarkable capacity to detect the correspondence of haptic (active tactual) and visual information about object substance.

The examples just described illustrate Gibson’s idea that differentiation is a fundamental process of perceptual learning. She disliked reductionism and was not interested in uncovering mechanisms of change at the physiological or neural level. Instead, she advocated the description of learning processes at the behavioral level. Differentiation as perceptual learning is a concept analogous at the behavioral level to the biological differentiation process where it refers to cell division and reorganization during embryonic development. For perceptual development, differentiation refers to discerning finer distinctions, finer discrimination of specific features, as well as abstracting higher order structure in the information available to the sensory systems. A previously mentioned illustrative example of perceptual learning in adults is learning to “read” radiological images. One learns to perceive more distinctions among the subtle shadings and also to discover or identify the structural patterns in the display. Perceptual development and learning in infants and young children is characterized by progressive increase in discrimination and detection of the meaningful properties of the environment, the affordances.

Gibson argued that exploratory behavior plays a fundamental role in perceptual learning and development, a point of view she elaborated on in a review essay titled “Exploratory Behavior in the Development of Perceiving, Acting, and the Acquiring of Knowledge” (1988). She summed up her argument by asking a rhetorical question, whether evolution has prepared infants to learn by providing “representations of the world, and rules for how to act?” Her answer: “I doubt that very much. But I think evolution has provided (them) with action systems and sensory systems that equip (them) to discover what the world is all about” (p. 37).

The Ecological Approach to Perceptual Learning and Development . Gibson’s approach to understanding perceptual development, like that of James Gibson for understanding perception, came to be called an “ecological” approach, emphasizing the reciprocity and complementarity of the animal (including humans) and the environment in which it lives and behaves. Beginning in about 1980 and continuing through the early years of the twenty-first century, the study of human development had a heavy emphasis on the period of infancy. This was also true of the study of development from an ecological perspective as Gibson and her colleagues, many of them former students, produced much new knowledge about the development of perception and action during infancy. The publication of a new book with Anne Pick, An Ecological Approach to Perceptual Learning and Development(2000), presented the theoretical formulation as it had evolved and incorporated much of the most recent research on perceptual development in infancy as it pertains to the theory.

The book is organized around three general modes of behavior that emerge during infancy and underlie and affect all subsequent complex activities. These are (1) early social interaction and communication, (2) the emergence of reaching and knowledge of objects, and (3) locomotion, getting around in the environment. With respect to each of these developing modes of behavior, Gibson stressed that learning changes the relations of a developing baby with the environment.

The first mode of behavior addressed in Gibson and Pick’s 2000 work is communication and social interaction. Although human newborns are completely dependent on adult caregivers, they begin life as active perceivers of their caregivers’ faces and voices. From the start infants participate in rudimentary face-to-face interactions, thus providing opportunities for learning from others. Care-givers’ affective expressiveness toward infants has obvious important significance as it may foretell comfort and soothing or distress or avoidance. Perceiving affect in others directed to oneself is thus an important achievement, and infants begin to develop sensitivity to facial and vocal expressions during their first months of life. In addition to facial/gestural patterns, infants come to detect information for affective meaning in the intonation, rhythm, and stress patterns of others’ speech.

The second mode of behavior addressed is the emergence of goal-directed reaching. Inanimate objects become accessible for exploration by the middle of the first year as infants gain motor and postural control necessary for reaching, grasping, and manipulating. Exploration by mouthing continues, however, as evidenced by the well-known proclivity of infants to transport objects of appropriate size and substance quickly and directly to their mouths. Exploratory behaviors—banging, throwing, squeezing, mouthing, shaking, and so on—are the means by which infants discover the affordances of objects. Especially important in such exploratory activities is multi-modal exploration, integrated exploration by more than one sensory modality. Important examples are visual and manual exploration, actively looking at and manipulating objects, examining them and bringing them up close for further scrutiny, mouthing and manipulating, and banging or shaking objects to learn about the sounds they make. Exploratory actions become increasingly differentiated in relation to objects’ specific properties.

The component abilities of goal-directed reaching develop earlier in infancy, including visually tracking moving objects, and gaining visual and motor control of arm movements. The development of such component skills of functional reaching demonstrate how exploratory actions are the means for linking perceptual information with motor control.

The third mode of behavior addressed by Gibson and Pick (2000) is learning to locomote. Human infants become capable of active self-locomotion typically sometime during the latter months of their first year. Gibson emphasized that active self-locomotion emerges gradually, from rolling over, to changing posture to sitting, to crawling, cruising, and eventually bipedal locomotion, usually more or less in that order. The achievements of postural stability, orientation to the environment, and balance underlie the development of each new phase of locomotion. The research with crawling and walking babies locomoting over rigid and pliable surfaces described earlier highlights the role of perceptual exploration in guiding locomotion as new action systems gradually become available.

Persistence of Perceptual Learning in Cognitive Development . Gibson’s research during her last decades as well as her theorizing was concentrated on development during infancy. Her discoveries countered a view prevalent at the time that in the course of development beyond infancy, perceiving becomes overridden by knowledge acquired by “higher” cognitive processes. Further, Gibson’s own earlier research—for example, on reading—attests that perceptual learning is fundamental for later achievements of language, conceptualization, and thinking.

What characterized Gibson’s approach to her science? First, beginning with her dissertation, her experimental investigations were always theoretically motivated. This meant that not only were the immediate empirical results informative, but also that the theoretical and conceptual analysis that was the context for the problem yielded new understanding and questions. Second, her experimental questions were posed clearly and distinctly, permitting the use of straightforward and rigorous methods to answer them. The research in which she discovered that young infants perceive objects’ substance (solid or elastic) from kinetic information as they move in particular ways illustrates this characteristic of her research.

Finally, she devised elegantly simple tasks and situations to investigate her experimental questions. The visual cliff is perhaps the most well-known example of this characteristic of her science. She was a consummate experimenter. In a memorial tribute, Elizabeth Spelke, a student of Gibson’s and herself an eminent scientist, wrote that at Gibson’s death at the age of ninety-two, “we lost the greatest experimental psychologist of the twentieth century. Twenty-first century psychology will be built on the comparative, developmental, and experimental foundations that Eleanor J. Gibson gave us” (2003, p. 26).

BIBLIOGRAPHY

WORKS BY GIBSON

“Sensory Generalization with Voluntary Reactions.” Journal of Experimental Psychology 24 (1939): 237–253.

“A Systematic Application of the Concepts of Generalization and Differentiation to Verbal Learning.” Psychological Review 47 (1940): 196–229.

“Retroactive Inhibition as a Function of Degree of Generalization Between Tasks.” Journal of Experimental Psychology 28 (1941): 93–115.

“Intralist Generalization as a Factor in Verbal Learning.” Journal of Experimental Psychology 30 (1942): 185–200.

With James J. Gibson. “Perceptual Learning: Differentiation or Enrichment?” Psychological Review 62 (1955): 32–41.

With Richard D. Walk. “The Effect of Prolonged Exposure to Visually Presented Patterns on Learning to Discriminate Them.” Journal of Comparative and Physiological Psychology 49 (1956): 239–242.

With Richard D. Walk. “A Comparative and Analytical Study of Visual Depth Perception.” Psychological Monographs 75, no. 15 (1961).

Principles of Perceptual Learning and Development. New York: Appleton-Century-Crofts, 1969.

With Harry Levin. The Psychology of Reading. Cambridge, MA: MIT Press, 1975.

With Cynthia J. Owsley and J. Johnston. “Perception of Invariants by Five-Month-Old Infants: Differentiation of Two Types of Motion.” Developmental Psychology 14 (1978): 407–415.

“Eleanor J. Gibson.” In A History of Psychology in Autobiography, Vol. VII, edited by Gardner Lindzey. San Francisco: W. H. Freeman, 1980.

“The Concept of Affordances in Perceptual Development: The Renascence of Functionalism.” In The Minnesota Symposia on Child Psychology, Vol. 15: The Concept of Development, edited by W. Andrew Collins. Hillsdale, NJ: Erlbaum, 1982.

With Arlene S. Walker. “Development of Knowledge of Visual-Tactual Affordances of Substances.” Child Development 55 (1984): 453–460.

With Gary Riccio, Mark A. Schmuckler, Thomas A. Stoffregen, et al. “Detection of the Traversability of Surfaces by Crawling and Walking Infants.” Journal of Experimental Psychology: Human Perception and Performance 13 (1987): 533–544.

“Exploratory Behavior in the Development of Perceiving, Acting, and the Acquiring of Knowledge.” Annual Review of Psychology 39 (1988): 1–41.

With Mark A. Schmuckler. “Going Somewhere: An Ecological and Experimental Approach to Development of Mobility.” Ecological Psychology 1 (1989): 3–25.

An Odyssey in Learning and Perception. Cambridge, MA: MIT Press, 1991.

With Ann D. Pick. An Ecological Approach to Perceptual Learning and Development. New York: Oxford University Press, 2000.

Perceiving the Affordances: A Portrait of Two Psychologists. Mahwah, NJ: Lawrence Erlbaum, 2002.