What Is The Visual Cliff

Apparatus used to test depth perception in babies

This female parent is encouraging her child to crawl across the visual cliff. The kid hesitates to movement frontwards as they come across the transparent surface.

The visual cliff is an apparatus created by psychologists Eleanor J. Gibson and Richard D. Walk at Cornell University to investigate depth perception in homo and other brute species. It consists of a sturdy surface that is flat but has the appearance of a several-foot drop office-way across. The visual cliff appliance allowed them to conduct an experiment in which the optical and tactile stimuli associated with a simulated cliff were adjusted while protecting the subjects from injury.^[1]

Using a visual cliff appliance, Gibson and Walk examined possible perceptual differences at crawling age between human being infants born preterm and man infants built-in at term without documented visual or motor impairments.^[2]

Blueprint [edit]

The visual cliff consisted of a sheet of Plexiglas that covers a cloth with a loftier-dissimilarity checkerboard pattern. On ane side the cloth is placed immediately beneath the Plexiglas, and on the other it is dropped nigh four feet (one.2 m) below.

Original study [edit]

Gibson and Walk (1960)^[1] hypothesized that depth perception is inherent equally opposed to a learned procedure. To test this, they placed 36 infants, half-dozen to fourteen months of age, on the shallow side of the visual cliff appliance. Once the infant was placed on the opaque stop of the platform, the caregiver (typically a parent) stood on the other side of the transparent plexiglas, calling out for them to come or property an enticing stimulus such as a toy. This immune so the infant would be motivated to crawl across towards them. Information technology was causeless if the kid was reluctant to clamber to their caregiver, he or she was able to perceive depth, assertive that the transparent space was an actual cliff.^[3] The researchers found that 27 of the infants crawled over to their mother on the "shallow" side without whatsoever problems.^[4] A few of the infants crawled merely 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 clamber, they tin can perceive depth.^[1] However, results do not indicate that avoidance of cliffs and fear of heights is innate.^[i]

Infant studies [edit]

During early development, infants begin to crawl, sit, and walk. These actions impact how the infants view depth perception. Thus, babe studies are an important part of the visual cliff. When an infant starts to engage in crawling, to sit, or walking, they utilize perception and activeness. During this time, infants begin to develop a fright of height. The everyday exploration of infants gives them clues about things or objects to avoid when exploring.^[v] Other research that has used the visual cliff focuses on preterm infants, prelocomotor Infants, and maternal signaling.

Preterm infants [edit]

Xvi infants born at term and sixteen born preterm were encouraged to clamber to their caregivers on a modified visual cliff. Successful trials, crossing fourth dimension, duration of visual attending, elapsing of tactile exploration, motor strategies, and avoidance behaviors were analyzed. A significant surface effect was institute, 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 built-in 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 modify their responses appropriately.^[2]

Prelocomotor infants [edit]

Another written report measured the cardiac responses of human infants younger than crawling age on the visual cliff.^[6] 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 betwixt the two sides of the cliff.^[vii]

Maternal signaling [edit]

James F Sorce et al. tested ^[8] to meet how maternal emotional signaling affected the behaviors of one-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 involvement most of the babies crossed the deep side but if the mothers posed fear or anger, about of the babies did not cross the apparatus.

On the contrary, in the absence of depth, nigh of the babies crossed regardless of the mother'due south facial expressions. This suggests that babies look to their mother's emotional expressions for advice near often when they are uncertain nigh the situation.^[9] Joseph J. Campos inquiry focuses on facial expressions between the caregiver and infant. Specifically his researcher shows that the infants will not crawl if the caregiver expresses a bespeak of distress. If the caregiver gives the babe a positive facial expression the kid is more likely to crawl beyond the visual cliff.

Non-human experiments [edit]

Before Gibson and Walk conducted their study with human infants, multiple experiments were conducted using rats, one-day-old chicks, newborn kids, kittens, pigs, adult chickens, dogs, lambs, and monkeys. Overall, most species would avert the deep side of the visual cliff, some right afterward being born. The first visual cliff experiment was conducted with rats who were raised in the dark and in the light. The results were that both groups of rats would walk all over the shallow and deep parts of the cliff without an outcome, which surprised Gibson, Walk, and Thomas Tighe (a enquiry assistant). A later on experiment with kittens raised in the night and then placed on the visual cliff showed that depth perception was not innate in all species as the kittens would walk on either side of the visual cliff. After 6 days of existence in the light, the kittens would avoid the deep side of the visual cliff (Rodkey, 2015). Later researchers conducted experiments using other species.^[10]

Rats [edit]

Rats do not depend upon visual cues similar 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 testify petty preference for either side of the visual cliff appliance every bit long as they could experience the glass with their vibrissae. When placed upon the glass over the deep side, they motility virtually equally if there was no cliff.^[11]

Cats [edit]

Cats, like rats, are nocturnal animals, sensitive to tactual cues from their vibrissae. Only the cat, as a predator, must rely more on its sight. Kittens were observed to have excellent depth-discrimination. At four weeks, the primeval age that a kitten tin can skillfully move nearly, they preferred the shallow side of the cliff. When placed on the glass over the deep side, they either freeze or circumvolve astern until they reach the shallow side of the cliff.^[11]

Turtles [edit]

The late Robert G. Yerkes of Harvard University establish in 1904 that aquatic turtles take somewhat worse depth-discrimination than land turtles. On the visual cliff one might await 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 information technology less occasions to "fear" a fall.^[11]

Cows [edit]

The ability for cows to perceive a visual cliff was tested by NA Arnold et al. Twelve dairy heifers were exposed to a visual cliff in the grade of a milking pit while walking through a milking facility. Over this v-day experiment the heifers' centre rates were measured forth 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 grouping were non. The experimental group was establish to have significantly higher heart rates and stop more than frequently than the heifers in the command group. Depth exposure did not have whatsoever effect on cortisol levels or the ease of treatment of the animals. These findings provide bear witness of both depth perception and acute fearfulness of heights in cows. This may lead to a reorganization of the way milking factories function.^[12]

Criticisms [edit]

One of the criticisms of the visual cliff study was whether the research in the written report actually supported the hypothesis that depth perception was innate in humans. Ane issue was about the glass over the deep part of the visual cliff. By roofing up the deep side with drinking glass the researchers enabled the babies to feel the solidity of the drinking glass before they would cross over. This response was repeated over and over again in tests.^[thirteen] Another criticism has to do with the experience of the infant. Infants who learned to crawl before half-dozen.v months of age had crossed the glass, but the ones that learned to clamber after 6.v months of historic period avoided crossing the glass. This helps support the hypothesis that feel does influence avoidance of the glass, rather than just existence innate.^[14]

See too [edit]

Developmental psychology
Psychology
Cognitive psychology

References [edit]

^ ^a ^b ^c ^d Gibson, E.J.; Walk, R.D. (April 1960). "Visual Cliff". Scientific American. 202 (4): 64–71. Bibcode:1960SciAm.202d..64G. doi:10.1038/scientificamerican0460-64. PMID 13827949.
^ ^a ^b Lin, Yuan-Shan; Rielly, Marie; Mercer, Vicki Due south. (2010). "Responses to a Modified Visual Cliff by Pre-Walking Infants Born Preterm and at Term". Physical & Occupational Therapy in Pediatrics. 30 (1): 66–78. doi:10.3109/01942630903291170. PMID 20170433. S2CID 1378458.
^ Cherry, Kendra. What Is a Visual Cliff? psychology.about.com.
^ Watch Out For The Visual Cliff date= 2014-02-05 at the Wayback Machine (archived 2013-02-05)^{[ unreliable source? ]} The Neuron (29 March 2009).
^ Karen, Adolph (2017). "Specificity of Learning: Why Infants Fall Over a Veritable Cliff". Psychological Science. 11 (four): 290–295. doi:10.1111/1467-9280.00258. PMID 11273387. S2CID 17845674.
^ "Babe Experiments: The Visual Cliff | Stellar Caterpillar". Retrieved 2019-xi-24 .
^ Campos, J. J., Langer, A., & Krowitz, A. (1970). "Cardiac Responses on the Visual Cliff in Prelocomotor Human Infants". Science. 170 (3954): 196–7. Bibcode:1970Sci...170..196C. doi:10.1126/science.170.3954.196. PMID 5456616. S2CID 28877905. {{cite periodical}}: CS1 maint: multiple names: authors list (link)
^ maternal emotional signaling^{[ total commendation needed ]}
^ Gibson, East. J., Walk, R. D., & Tighe, T. J. (1957). "Beliefs of Lite- and Dark-Reared Rats on a Visual Cliff". Science. 126 (3263): 80–81. Bibcode:1957Sci...126...80W. doi:x.1126/science.126.3263.lxxx-a. PMID 13442652. S2CID 36208087. {{cite periodical}}: CS1 maint: multiple names: authors list (link)
^ Rodkey, Elissa (Bound 2015). "The Visual Cliff'south Forgotten Menagerie: Rats, Goats, Babies, and Myth-Making in the History of Psychology". Journal of the History of the Behavioral Sciences. 51 (2): 113–140. doi:x.1002/jhbs.21712. PMID 25728287.
^ ^a ^b ^c Fantz, R.L. (1961). "The origin of form perception". Scientific American. 204 (5): 66–72. Bibcode:1961SciAm.204e..66F. doi:10.1038/scientificamerican0561-66. PMID 13698138.
^ Arnold, N. A., Ng, K. T., Jongman, E. C., & Hemsworth, P. H. (2007). "Responses of dairy heifers to the visual cliff formed by a herringbone milking pit: testify of fear of heights in cows (Bos taurus)". Journal of Comparative Psychology. 121 (4): 440–6. doi:x.1037/0735-7036.121.iv.440. PMID 18085928. {{cite journal}}: CS1 maint: multiple names: authors listing (link)
^ Adolph, Chiliad. Due east., & Kretch, Chiliad. S., "Infants on the Edge: Beyond the Visual Cliff". In A. Slater, & P. Quinn (Eds.), Developmental psychology: Revisiting the classic studies (pp. 36-55). SAGE Publications. 2012
^ Nancy Rader, Mary Bausano and John Due east. Richards, "On the Nature of the Visual Cliff Avoidance Response in Man Infants". Child Dev. 1980 Mar;51(1):61-8. PMID 7363749

External links [edit]

Visual Cliff Video