Sensory Experience, Adaptation, and Perception

Festschrift for Ivo Kohler

Lothar Spillman, Bill R. Wooten

• Publisher: Psychology Press
• Year: 2013
• Print ISBN: 9780898592184
• eBook ISBN: 9781134921133
• Topic: Psychology
• Subtopic: Cognitive Psychology & Cognition
• Index: Psychology

Published in 1983, Sensory, Experience, Adaptation, and Perception is a valuable contribution to the field of Cognitive Psychology.

I	HISTORICAL REVIEWS

1	Through the Looking Glass and What Ivo Kohler Found There: Contours, Colors and Situational Aftereffects

Alberta S. Gilinsky

University of Bridgeport

ABSTRACT

Kohler's Innsbruck experiments with distorting goggles resulted in variable aftereffects and variable degrees of resistance to reconditioning and correct seeing. Recent neurophysiological discoveries based on receptive field studies of cats and monkeys subjected to “environmental surgery” are here shown to account for Kohler's remarkable research and its fruitful extension into modern psychophysiology. The use of Konorski's theory as a framework into which to fit both lines of investigation provides the synthesis of two points of view desired by Kohler. that of “situational aftereffects” and “conditioned sensations.”

Alice looked round eagerly and found that it was the Red Queen. “She's grown a good deal,” was her first remark. She had indeed: when Alice first found her in the ashes, she had been only three inches high—and here she was, half a head taller than Alice herself….

“I think I'll go and meet her.” said Alice, for though the flowers were interesting enough, she felt that it would be far grander to have a talk with a real Queen.

“You can't possibly do that,” said the Rose. “I should advise you to walk the other way.”

This sounded nonsense to Alice, so she said nothing, but set off at once towards the Red Queen. To her surprise she lost sight of her in a moment, and found herself walking in at the front door again.

A little provoked, she drew back, and after looking everywhere for the Queen (whom she spied out at last, a long way off) she thought she would try the plan this time, of walking in the opposite direction.

It succeeded beautifully. She had not been walking a minute before she found herself face to face with the Red Queen, and full in sight of the hill she had been so long aiming at. (Carroll, 1872, p. 191–192)

Lewis Carroll might have been a subject in one of the Innsbruck experiments (Kohler, 1962; 1964) with goggles. These subjects wore reversing mirrors, prismatic and half-prism spectacles, even split-color goggles to study the effects of these experimental disturbances on behavior and perception. Forward and back are reversed in a mirror, as are left and right; objects are simultaneously enlarged and reduced—in a mirror all asymmetrical objects (objects not superposable on their mirror images) “go the other way.”

The prism goggles reverse right and left, and near and far. They also change the sizes of things in a surprising way, depending upon the direction of gaze. When Alice eats the left side of the mushroom she grows larger; the right side has the reverse effect.

The fact that the first verse of the Jabberwocky appeared reversed to Alice is evidence that she herself was not reversed by her passage through the mirror. Martin Gardner (1965) points out that there are new scientific reasons for suspecting that an unreversed Alice could not exist for more than a fraction of a second in a looking glass world composed of “antimatter.”

Ivo Kohler and his subjects not only survived long periods of wearing goggles that warp, distort, reverse, invert, and recolor the familiar world, but overcame the disturbances with new habits of both behavior and perception—habits that ran counter to a lifetime of previous experience and activity.

The Innsbruck experiments uncovered an adaptive process of general validity. The most remarkable finding—Ivo Kohler's gay and wonderful discovery that stimulation of the same retinal area could lead not only to a variety of visual aftereffects but that these aftereffects were contingent upon the presence or absence of certain conditions of stimulation—is called both “the situational aftereffect” and “conditioned perception.”

The discovery was prophetic. Now as the result of a series of remarkable psychophysiological experiments we are beginning to understand the organization of the perceptual system and its modification as the result of experience.

The central finding of the Innsbruck studies was the differential adaptation that occurred in one and the same area of the retina. “It is as though,” Kohler wrote, “the particular retinal area had not one but a whole series of subjective standards of reaction for the same visual stimulation” (1964, p. 26).

The problem is to explain the occurrence of variable aftereffects; variable degrees of resistance to the transformation of old habits and the formation of new habits; the lead role of motor behavior and only secondarily, of vision; and complete failure of certain visual phenomena, e.g., the color-stereo effect, to show any adaptation, whatsoever.

Kohler's insight into the value of these experiments as probes to discover the genesis of correct perception and coordinated visual-motor behavior in normal development is now confirmed by new discoveries of the activity and organization of the cerebral cortex.

RECEPTIVE FIELD STUDIES

In the mammalian visual system, the important discovery is that any given retinal area transmits information to the brain in a hierarchy of stages of neural activity, corresponding to increasingly higher orders of abstraction of specific features of stimulation. Especially significant is the finding that single cells in the eye and brain are organized into receptive fields of mutually antagonistic activity. In consequence, the visual system tends to dichotomize perception not only into such opposites as light and dark, black and white, red and green, but also into such spatial opposites as left and right, near and far, above and below, and concave and convex. This opponent organization is maintained by a functional architecture that enables us to respond selectively not to absolute properties of stimulation but to the relations between them.

We find selectivity at every stage. A particular retinal area gives different reactions to the same total stimulation at different times and under different conditions because cells farther upstream select the features to which they respond and reject the others. Some regions react to the onset; others to the offset of stimulation. Individual neurons react to lines, bars or gratings with specific sizes, shapes, orientations, directions of movement, and contrasts, dark against light, or light against dark backgrounds. This selective processing is repeated again and again at progressively higher levels. In this processing, the neural activity sharpens gradations and turns them into contours.

Direction is an important factor in the perception of form since the same contour will look different if it is attached to the right or to the left, above or below the figure it outlines. The receptive field studies show clearly that both the direction of movement and the brightness gradient or spatial phase (light to dark, or dark to light) is critical for the response of a single cortical cell in cat or monkey. Human perception emphasizes this feature of contour also; the onesided action of contour is fundamental to the discrimination of objects and the segregation of figure and ground.

The apparent paradox of opposite aftereffects arising from one retinal area is no longer bewildering. Having available the data derived from Hubel and Wiesel's (1962; 1979) experiments, we know that the same retinal area sends convergent and divergent impulses to many cells of different receptive field types. Single cell studies using microelectrodes have examined and compared the effective stimuli for cells of the visual pathway from the retina to successive levels of the cortex in cat and monkey. Their results provide a physiological and anatomical basis for understanding the sensory disturbance experiments in animals and human beings.

The visual cortex of cats and monkeys contains sets of neurons that receive information from lower levels of the visual pathways and are cither excited or inhibited by slits of light or gratings selectively oriented and placed in the visual field. Within the cortex each region of visual space is “… represented over and over again in column after column, first for one receptive field organization and then another” (Hubel & Wiesel, 1962, p. 106). Although there appears to be an initially organized functional architecture ready to work soon after birth, the details of these structures depend strikingly on the previous experience of the individual.

Most neurons in the visual cortex of normal cats and monkeys respond selectively to moving contrasts, lines, or gratings presented to one eye alone or both eyes together. Some cortical cells react preferentially to vertical, some to horizontal, and some to oblique orientations of lines or gratings with all orientations being represented. Cells with similar characteristics are grouped together; their receptive fields are close together also; usually they overlap but each group includes various sizes and some scatter. The important point is that each small region of the retina has input to many cells with different response characteristics and different stimulus requirements. Sweeping an optimally oriented grating across the receptive field of a cell is a powerful stimulus, depending on the direction of movement, although some cells respond to movement in two diametrically opposite directions. The cell soon adapts to continued or repeated stimulation and ceases to respond, although the termination of a stimulus may evoke a burst of excited activity.

Long sequences of cells with the same receptive field orientation are found as the electrode advances through the cortex; then a sudden shift occurs to a new sequence with a common orientation preference. These cell sequences are grouped together in columns containing tens of thousands of cells. Any small region of the retina is represented by many columns subserving different stimulus features. The aggregate fields are linked to eccentricity, or the distance of a cell's receptive field from the center of gaze. “Moving the electrode about 1 or 2 mm in an oblique direction always produces a displacement in the visual field that takes one into an entirely new region. Strongly interconnected cells are grouped together and neighboring regions are not random but systematically related to each other in orderly progression…. The column systems are a (possible) solution to the problem of portraying more than two dimensions on a two-dimensional surface … the cortex is dealing with at least four sets of values: two for the X and Y position variables in the visual field, one for orientation and one for the different degrees of eye preference” (Hubel & Wiesel, 1979, p. 162).

SENSORY DISTURBANCE EXPERIMENTS

The Innsbruck experiments on the transformation of human perception fit hand in glove with the recent neurophysiological studies of the effects of early distortion of sensory input on the visual system of kittens and monkeys.

Taken together with the research on single cells of the nervous system in various species, these different lines of investigation enable us to understand how the structure and function of the brain are affected by the history of the organism. The ability to undergo long-term alterations as a result of experience is a remarkable property of the nervous system. The factors that influence this relearning or rehabituation are presumably no different than those involved in the initial formation of the perceptual world.

Yet there is one important exception. A brief early experience during a critical period of development may cause irreversible effects. In newborn animals the closure of one eye may result in permanent damage even though the neuronal circuits required for vision were already present and ready to work at birth (Hubel & Wiesel, 1963). Kittens are born with the basic wiring already established. Both eyes drive cortical neurons and these cells have receptive fields like those in the adult cat. Some cells are driven better by one eye, some by the other and some are driven equally well by both eyes. What happens when one eye is deprived of all visual experience?

Hubel and Wiesel (1965) tried the experiment on a newborn kitten by sewing the lid of one eye closed for 3 months and then recorded the activity of the cortical cells. The effect in the kitten's visual cortex was extraordinary. Not a single cell could be influenced by the eye that had been closed.

When the previously deprived eye was opened and the experienced eye closed (reverse suturing) the kittens were practically blind. They would bump into objects and fall off tables even though no gross defect could be found in the operated eye. But electrical recordings of the responses of cortical cells showed striking changes. Very few cells showed any response to the stimulation of that eye. In short, deprivation of the use of one eye at a critical period of development leads to permanent loss of function in that eye. As little as a day of deprivation at about 4 weeks of age (the height of a “sensitive period”) can provoke the permanent reorganization of the visual cortex in the kitten (Movshon & Dürsteler, 1977; Olson & Freeman, 1975).

In the kitten, Blakemore and Van Sluyters (1974) have shown that if the originally experienced eye is closed at the time that the deprived one is reopened there can be virtually total capture of neurons by the newly opened eye. This reverse suturing procedure is more effective the earlier in the sensitive period it is done; at 4 or 5 weeks of age it causes total re-invasion of input from the deprived eye. Blakemore, Garcy, and Vital-Durand (1978) found the same result in monkeys following reverse suturing. After early reverse suturing (5–8 weeks) the newly opened eye gained complete dominance.

EFFECTS OF ABNORMAL VISUAL EXPOSURE

If young kittens are raised during the critical period (3–14 weeks) in a visual environment consisting only of stripes of one orientation, most cortical neurons will be maximally sensitive to orientations within ± 30° of the one to which they had been exposed. That may sound like a wide range until you consider that the hands of the clock between 12 and 1 o'clock are 30° apart.

What are the effects of selective exposure to tilt on mature animals? Creutzfeldt and Heggelund (1975) exposed seven adult cats to vertical stripes for 1 hour a day and for...

Table of contents

• Cover
• Full Title
• Copyright
• Contents
• Preface
• For Ivo Kohler: Scientist and Teacher on the Occasion of His 65th Birthday
• Publications by Professor Ivo Kohler
• List of Selected Readings on Perceptual and Sensori-motor Adaptation: Historical Beginnings, Monographs, and Recent Reviews
• Bibliography of Japanese Studies of Disarranged Vision
• PART I: HISTORICAL REVIEWS
• PART II: THEORY
• PART III: SPACE PERCEPTION AND BODY ORIENTATION
• PART IV: DIRECTIONAL ADAPTATION AND LEARNED REVERSAL
• PART V: INDUCTION BY BRIGHTNESS, COLOR, ORIENTATION, MOTION, AND DEPTH
• PART VI: NEUROPSYCHOLOGICAL EVALUATION OF CENTRAL VISUAL DEFICITS
• Author Index
• Subject Index