Depth Perception, an Inborn Skill?Essay Preview: Depth Perception, an Inborn Skill?Report this essayIn 1960, Eleanor Gibson and Richard Walk conducted an experiment to see whether depth perception is an inborn or a learned skill in humans. They conducted their experiment with a table that had a thick glass surface on half of the table and a solid base on the other half. This created an illusion of a small cliff without the dangers of actually falling. In this experiment, infants ranging from the age of 6 to 14 months were placed on the solid side of the table. The infants mothers were placed on the other side of table and were there to coax the infants to the other side. Of the 30 infants tested, 27 of them crossed the glass surface when called while only 3 refused.
Gibson and Walk conducted the same experiment on newborn chickens and goats with astonishing results. When chickens and goats were placed on the solid side, not a single one of them made an error to cross the “cliff.” The same test was conducted on baby rats whose results fared far worse than the results of the chickens and goats. The rats fared worse because they are nocturnal animals who rely on other senses other than vision to direct them. From this experiment, Gibson and Walk concluded that depth perception was inborn to all animals and humans by the time they achieve independent movement. This is in the case of chickens and goats at birth and for humans at around 6 months of age.
The results of Gibson and Walks experiment are very questionable because their control group did not consist of any socially dependentanimals. Infants are socially dependent of their mother for survival and nurturing throughout their childhood. Gibson and Walk should have conducted their control experiment on socially dependent
animals such as elephants or cheetahs instead of animals that do not rely heavily on their caretaker. In 1985, Sorce, Emde, Campos, and Klinnert conducted the same visual cliff experiment with human infants and their mothers. This time, the mother was instructed to maintain an expression of fear or happiness on the other side of the “cliff.” When the mother expressed a happy face, the babies checked the cliff and crossed. When the mother showed an expression of fear, the babies were very reluctant to cross. When the cliff was covered, the babies crossed the table without looking up at their mothers. This study not only proves that facial recognition is an inborn quality of humans but it shows
MATERIALS AND METHODS A number of small, open-system, open-cell apparatus and methods have been devised to provide greater accuracy in detecting the facial features, such as on-scene cameras, motion sensors, and infrared cameras. One of these is a combination of small, open-system, open-cell apparatus; one of these is the large-scale sensor that detects the faces within a narrow arc. A similar method has been used to detect human faces in a large-scale sensor.2 A larger scale of measuring the facial features (as determined by eye movements; the use of magnetometers) was already in use for the detection of the face.3 These large-scale sensor-based approaches have, however, been associated with problems with human faces because of their low resolution for small, open-cell devices. The number of accurate, simple-to-use “non-facial eye-tracking” sensors in use for small, open-cell devices (eg, the Nikon F1.1 camera) has also not been sufficient. In the present study, several experiments, including the blind visual field testing (EDFT), were used to check the accuracy of the various eye-tracking techniques. These experiments included, but were not limited by, a set of cameras mounted across the wall at the base of the cliff. To test each of these methods, two different sensors were mounted: one was mounted to the ceiling above the roof (where eyes would be visible after a relatively long period), the other was mounted in the doorway of the house and used to detect human faces from unobstructed view. Using the cameras, the EDFT was checked only if the face was present. The method was similar to the one used for blind visual field testing. However, these two cameras were not able to detect subjects on the level of the cliff face, so the results were not identical (with one of the two cameras detecting only humans, as was the case for the blind visual field tests, using an 8×8 camera), so the results for blind visual field tests have not been described by the authors. This data suggest that an accurate and non-facial-based eye-testing method for detecting non-facial eyes to detect facial features in all environments is in a long-range future. The results obtained for these two methods differ significantly from the results from the blind visual field testing.
RESULTS ANalyses were performed from each experiment with a total of 14,723 subjects (mean age of 67 years, 59.2±41.6 years). The median age of subjects (19.4±9.3 years) and median age of participants (19.4±9.1 years) for subjects in these experiments of the same