A2 PSYA3 - How many marks is my essay?Watch
One research study carried out by Gibson and Walk, aimed to look at the development of depth and distance cues in infants. They constructed a visual cliff apparatus, which halfway through, showed a drop underneath a glass table of a checked material. The glass continued to reside over the drop. Thirty six infants aged 6-14 months, were placed on the shallow end of the visual cliff. Their mothers stood on the side beyond the drop, encouraging the infants to cross the cliff.
The results showed that infants would crawl over the shallow part, but not over the drop. If they accidently toppled towards the drop they showed a fear reaction. It is therefore assumed they were able to detect depth and Gibson believed they used motion parallax to do this. However, since infants of 6 months had to be used as they had the ability to crawl, it could be argued they had learnt through experience to develop depth perception.
In response to this criticism Gibson carried out an animal study to test this hypothesis. Animals that can walk almost from birth such as kittens and chicks were used on the visual cilff. They were found to hesistate crossing over the drop. If placed above the drop they froze and wouldn't stand, indicating fear and knowledge of the dangers involved. Since these animals were just born they couldn't have learnt depth cues through experience, proving they were instinctual. This study would have been easier to carry out in practical terms, as the animals could walk after birth. However, perceptual development may be different in animals than in humans, and maturation may occur at different rates. This means the results can't for sure be generalised to humans making it difficult to make solid conclusions.
Indeed parental consent was required for Gibson's study and so having the infants' mothers being part of the experiment provided useful. The infants may have suffered mild distress upon being separated from their mothers by a frightening obstacle. The animals used have to be taken care of ethically during experiments as strict rules apply. The benefits of the study must be worthy of putting animals through any distress through experimentation.