07.09.2019
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The images of the 1959 visual cliff experiment — the red-and-white checkered surface, the baby hesitating at the edge of a glass-topped drop-off, the beckoning mother — rank among psychology’s most famous, familiar even to introductory psychology students. In perception: Innate versus learned perception human babies. One technique (the visual cliff) depends on the evident reluctance of young animals to step off the. More Visual Cliff images.
The visual cliff apparatus was created by psychologists and Richard D. Walk at to investigate in human and animal species. This apparatus allowed them to experimentally adjust the optical and tactical stimuli associated with a simulated cliff while protecting the subjects from injury. The visual cliff consists of a sheet of that covers a cloth with a high-contrast pattern. On one side the is placed immediately beneath the Plexiglas, and on the other, it is dropped about 4 feet below. Since the Plexiglas supports the weight of the this is a visual cliff rather than a drop off.
Using a visual cliff apparatus, Gibson and Walk examined possible perceptual differences at crawling age between human infants born preterm and human infants born at term without documented visual or motor impairments. Contents. The original visual cliff study Gibson and Walk (1960) hypothesized that depth perception is inherent as opposed to a learned process. To test this, they placed 36 infants, 6 to 14 months of age, on the shallow side of the visual cliff apparatus. Once the infant was placed on the opaque end of the platform, the caregivers (typically a parent) stood on the other side of the transparent plexiglas, calling out for them to come or holding some sort of enticing stimulus such as a toy so that the infant would be motivated to crawl across towards them. It was assumed if the child was reluctant to crawl to their caregiver, he or she was able to perceive depth, believing that the transparent space was an actual cliff. The researchers found that 27 of the infants crawled over to their mother on the 'deep' side without any problems.
A few of the infants crawled but were extremely hesitant. Some infants refused to crawl because they were confused about the perceived drop between them and their mothers. The infants knew the glass was solid by patting it, but still did not cross. In this experiment, all of the babies relied on their vision in order to navigate across the apparatus. This shows that when healthy infants are able to crawl, they can perceive depth. However, results do not indicate that avoidance of cliffs and fear of heights is innate. Human infants studies Preterm infants Sixteen infants born at term and sixteen born preterm were encouraged to crawl to their caregivers on a modified visual cliff.
Successful trials, crossing time, duration of visual attention, duration of, and were analyzed. A significant surface effect was found, with longer crossing times and longer durations of visual attention and tactile exploration in the condition with the visual appearance of a deep cliff. Although the two groups of infants did not differ on any of the timed measurements, infants born at term demonstrated a larger number of motor strategies and avoidance behaviors by simple tally. This study indicates that infants born at term and those born preterm can perceive a visual cliff and change their responses accordingly. Prelocomotor infants Another study measured the cardiac responses of younger than crawling age on the visual cliff. This study found that the infants exhibited distress less frequently when they were placed on the shallow side of the apparatus in contrast to when they were placed on the deep side.
This means that prelocomotor infants can discriminate between the two sides of the cliff. Maternal signaling James F Sorce et al. Tested to see how maternal emotional signaling affected the behaviors of 1-year-olds on the visual cliff. To do this they placed the infants on the shallow side of the visual cliff apparatus and had their mothers on the other side of the visual cliff eliciting different emotional facial expressions. When the mothers posed joy or interest most of the babies crossed the deep side but if the mothers posed fear or anger, most of the babies did not cross the apparatus. On the contrary, in the absence of depth, most of the babies crossed regardless of the mother’s facial expressions.
This suggests that babies look to their mother’s emotional expressions for advice most often when they are uncertain about the situation. The study in different species The visual cliff was not only tested on human infants, it was applied to other as well.
A few of these species included rats, cats, turtles, cows, and chickens. Rats do not depend upon visual cues like some of the other species tested. Their nocturnal habits lead them to seek food largely by smell. When moving about in the dark, they respond to tactual cues from their stiff whiskers (vibrissae) located on the snout. Hooded rats tested on the visual cliff show little preference for either side of the visual cliff apparatus as long as they could feel the glass with their vibrissae.
When placed upon the glass over the deep side, they move about as if there was no cliff. Cats , like rats, are nocturnal animals, sensitive to tactual cues from their vibrissae. But the cat, as a predator, must rely more on its sight. Kittens were observed to have excellent depth-discrimination.
At four weeks, the earliest age that a kitten can skillfully move about, they preferred the shallow side of the cliff. When placed on the glass over the deep side, they either freeze or circle backward until they reach the shallow side of the cliff. Turtles The late of Harvard University found in 1904 that aquatic turtles have somewhat worse depth-discrimination than land turtles. On the visual cliff one might expect an aquatic turtle to respond to the reflections from the glass as it might to water and prefer the deep side for this reason. They showed no such preference; 76% of the aquatic turtles crawled onto the shallow side. The large percentage that choose the deep side suggests either that this turtle has worse depth-discrimination than other animals, or that its natural habitat gives it less occasions to 'fear' a fall. Cows The ability for to perceive a visual cliff was tested by NA Arnold et al.
Twelve dairy heifers were exposed to a visual cliff in the form of a milking pit while walking through a milking facility. Over this five-day experiment the heifers’ heart rates were measured along with the number of times they stopped throughout the milking facility. Dairy heifers in the experimental group were exposed to a visual cliff while dairy heifers in the control group were not. The experimental group was found to have significantly higher heart rates and stop more frequently than the heifers in the control group. Depth exposure did not have any effect on cortisol levels or the ease of handling of the animals.
These findings provide evidence of both depth perception and acute fear of heights in cows. This may lead to a reorganization of the way milking factories function. Chicks Two-day-old responded to the visual cliff when tested by PR Green et al. As the depth of the visual cliff below the chicks was increased, the latency for the chick to move towards the incentive, another chick on the far side of the apparatus, was increased while the speed at which they moved decreased.
On the other hand, chicks that were given the same incentive to jump over a visible edge, onto the deep side of the apparatus, were less inclined to move at all depths. This illustrates that the absolute depth of a surface and the relative depth of an edge affect behavior differently in chicks. Lambs are able to stand and learn to walk almost as soon as they are born. Just like chicks, they were able to be tested as soon as they could stand. They did not make one error when tested on the visual cliff. When placed on the deep side of the glass, they would become scared and they would tense up and be afraid to move.
However, when they were moved to the shallow side they would relax and jump onto the visually shallow surface. This showed that visual sense, instead of the ability of the animal to feel the stableness of the glass, was in control. Criticisms One of the criticisms of the visual cliff study was, 'Did they really support the hypothesis that depth perception was innate in humans?' One issue was about the glass over the deep part of the visual cliff. By covering up the deep side with glass the researchers enabled the babies to feel the solidity of the glass before they would cross over. This response was repeated over and over again in tests.
Another criticism has to do with the experience of the infant. Infants who learned to crawl before 6.5 months of age had crossed the glass, but the ones that learned to crawl after 6.5 months of age avoided crossing the glass. This helps support the hypothesis that experience does influence avoidance of the glass, rather than just being innate. See also. References. ^ Gibson, E.J.; Walk, R.D. (April 1960).
Visual Cliff Article
Scientific American. 202 (4): 64. ^ Lin, Yuan-Shan; Rielly, Marie; Mercer, Vicki S. 'Responses to a Modified Visual Cliff by Pre-Walking Infants Born Preterm and at Term'.
Physical & Occupational Therapy in Pediatrics. 30 (1): 66–78. Cherry, Kendra. The Neuron (29 March 2009). J., Langer, A., & Krowitz, A.
'Cardiac Responses on the Visual Cliff in Prelocomotor Human Infants'. 170 (3954): 196–7. CS1 maint: Multiple names: authors list. Gibson, E.
D., & Tighe, T. 'Behavior of Light- and Dark-Reared Rats on a Visual Cliff'. 126 (3263): 80. CS1 maint: Multiple names: authors list. ^ Fantz, R.L. 'The origin of form perception'.
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T., Jongman, E. C., & Hemsworth, P.
'Responses of dairy heifers to the visual cliff formed by a herringbone milking pit: evidence of fear of heights in cows ( Bos taurus)'. Journal of Comparative Psychology. 121 (4): 440–6. CS1 maint: Multiple names: authors list.
Visual Cliff Questions
Adolph, K. E., & Kretch, K. S., Infants on the Edge: Beyond the Visual Cliff, Adobe PowerPoint. Nancy Rader, Mary Bausano and John E.
Richards, On the Nature of the Visual Cliff Avoidance Response in Human Infants, Adobe PowerPoint External links.
The images of the 1959 visual cliff experiment — the red-and-white checkered surface, the baby hesitating at the edge of a glass-topped drop-off, the beckoning mother — rank among psychology’s most famous, familiar even to introductory psychology students. The fame of this classic experiment, which established that infants can perceive depth by the time they learn to crawl, has overshadowed the brilliant woman behind the experiment — Eleanor J. Gibson (1910–2002). But Gibson’s life, including how she came to conduct the visual cliff experiment, is well worth remembering. Eleanor discovers two loves Eleanor Jack (popularly known as Jackie) got her start in psychology in 1927 at Smith College, where she discovered experimental psychology and her husband-to-be, James Gibson. Eleanor and James met at a Smith graduation garden party where she, a junior, was assigned to serve punch and he, a young professor, was assigned to greet parents.
A sudden rain caused them to seek shelter in the same area, which led to a ride home for Eleanor in James’s ancient Model T. The car ride left grease on her best blue organdy dress, but the next day Eleanor dashed back to campus to change her fall course schedule to include James’s advanced experimental psychology class before catching her train home for the summer. Eleanor’s love of psychology and James grew as she worked on her master’s in psychology at Smith, with James as her adviser. In 1932, they married. After a few years teaching at Smith, Eleanor got a year’s leave to pursue her doctorate at Yale’s new interdisciplinary Institute of Human Relations, where she managed to cram all of her required coursework into one year. Gibson chose Yale due to her desire for a “super-scientific, strongly experimental atmosphere where I could work with animals,” she later said.
But when Gibson approached Robert Yerkes, hoping to work in his chimpanzee lab, Yerkes proclaimed, “I have no women in my laboratory.” Science and laboratory work in particular were seen as masculine pursuits, with the laboratory environment incompatible with femininity. Instead, there were several areas within psychology that, consistent with, were unofficially demarcated as “women’s work,” such as developmental and applied psychology. Women like Gibson, who had their hearts set on hard science, had to be extraordinarily gifted and stubborn to succeed. The incident with Yerkes was the first of many occasions in which Gibson would experience gender barriers. Her response in this case was typical of her response to obstacles throughout her life: Rather than bemoaning the injustice of the situation, she sought creative alternatives that, while not ideal, would help her progress toward her goals.
In this case, Gibson asked Clark Hull to supervise her dissertation topic on differentiation and thus was able to pursue a topic she found interesting, even though she had to mask her true functionalist views with behaviorist terminology to fit her work within Hull’s research program. Gibson’s strategy of flexibility in the face of obstacles meant that she often worked in areas that were not directly related to her most central interests. However, reflecting on her career, Gibson had a sanguine take on this strategy: “I did have a theme, a sort of direction, and opportunities, even very unlikely ones, can sometimes be bent to one’s theme.” Stumbling into the visual cliff It was at Cornell University that Gibson’s struggles to conduct research began in earnest.
Like many schools at midcentury, Cornell had antinepotism rules that barred married couples from being hired by the same department. Since James Gibson received the offer from Cornell based on his groundbreaking perception research, this meant that Eleanor would work as an unpaid research associate at Cornell for 16 years. From 1949–1966, Gibson carried out her research by applying for government grants and partnering with Cornell faculty. The first of these endeavors was working as an assistant at the Behavior Farm, a laboratory of Cornell professor Howard Liddell, a staunch behaviorist engaged in the classical conditioning of goats using shock to induce experimental neurosis. Since goats were bred on the farm, Gibson also set up her own study of goat development and imprinting, but this research came to a premature end when she returned to the farm one weekend only to discover that some of her subjects had been given away as Easter presents. Frustrated by this experience, Gibson began collaborating with Richard Walk, whose Cornell faculty status meant he had access to laboratory facilities.
Together they conducted a series of experiments testing the effect of an enriched rearing environment on learning in rats. One experiment called for rats raised in the dark, and the invention of the visual cliff was the serendipitous result of Gibson’s and Walk’s attempt to get more use out of painstakingly dark-reared rats.
To their surprise, the dark-reared rats avoided the glass-covered drop-off portion of the cliff, showing that they could perceive depth despite their lack of visual experience. Gibson and Walk found that a variety of species could discriminate depth by the time they could walk, and animals such as chicks and goats that walk at birth could immediately perceive depth. Eventually, Gibson and Walk tested crawling babies on the cliff, using the presence of the babies’ mothers to motivate the infants to crawl. Their findings were published in Scientific American and covered in the popular press, including a feature in Life magazine. It quickly became one of psychology’s most famous experiments, its engaging photographs incorporated in numerous introductory textbooks.
Accolades in later life Over the course of Gibson’s career, her research interests converged on perceptual learning. In 1969, she published “Principles of Perceptual Learning and Development,” in which she argued for her differentiation theory of perceptual learning, in contrast to the dominant associationist theories. At the time of the book’s publication, accurate methods for studying perceptual development in infants were a relatively recent development, so there was a limited body of relevant research. Gibson’s review of the field and methodological suggestions in “Principles” thus served to galvanize the field and to define perceptual learning as a distinct research focus. In 1966, Cornell finally recognized Gibson’s accomplishments and made her a professor, complete with a lab where she could conduct the research she called for in “Principles.” Although she was resistant to a feminist interpretation of her life, in 1977 in a talk called “A Lab of One’s Own,” Gibson acknowledged the profound effect her lack of a laboratory had had on her career. Following Virginia Woolf’s “A Room of One’s Own,” Gibson connected her experience to those of women writers who lacked a quiet room in which to write: “Things have changed.
Most of us have a desk now. But a woman who would be a scientist needs a lab, too, a lab of her own.” Reviewing the course of her career, Gibson showed how her various research projects were each in response to her lack of a lab: “Couldn’t I just set out to work on the research of my choice? No, I couldn’t. One needs a lab, and I didn’t have one.” Yet her strategy of flexibility and creativity in response to career obstacles proved a winning one; in her later life, she received many accolades for her work, including the National Medal of Science in 1992. She was only the fifth psychologist ever to receive the award. Gibson accepted the award, wryly noting that the medal “has a picture of a man, of course.” Elissa N.
Rodkey is a psychology graduate student at York University. Milar, PhD, of Earlham College, is historical editor for “Time Capsule.” To see historic footage Dr.
Eleanor Gibson and Dr. Richard Walk made about their visual cliff experiment, go to. Caudle, F.M. Eleanor Jack Gibson. O’Connell & N. Russo (Eds.). Women of psychology: A bio-bibliographic sourcebook (104–116).
Westport, CT: Greenwood Press. Gibson, E.J. Principles of perceptual learning and development. New York: Meredith Corporation. Gibson, E.J.
Perceiving the affordances: A portrait of two psychologists. Mahwah, NJ: Lawrence Erlbaum Associates. Gibson, E.J., & Pick, A.D.
Perceptual learning and development: An ecological approach to perceptual learning and development. Oxford: Oxford University. Gibson, E.J., & Walk, R.D. The “visual cliff.” Scientific American, 202, 67–71. Johnston, E., & Johnson, A.
Searching for the second generation of American women psychologists. History of Psychology, 11, 40–69.
Visual Cliff Experiment
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