Nurturists believe we develop this ability over time, through experience and observation in our environment. For example, a child may reach for an object and will develop their hand-eye coordination by repetition of this action, as they begin to learn how far an object is, from how far away it appears to be. Nurturists support the nurture side of the nature/nurture arguments.
Nativists, on the other, believe that depth perception is an innate ability that we possess from birth. They believe that although the ability needs to mature to be fully functioning, it exists from birth. It is true that all the components necessary for depth perception exist, for example optic nerves which are shorter and narrower when a person is young (slowing the transmission of information from the eye to the brain). Nativists support the nature side of the nature/nurture debate.
Interactionists believe that although our abilities are innate, they need develop within our environments and certain internal systems need to mature. In the instance of depth perception, they are likely to argue that a developed visual system is necessary for accurate depth perception. Interactionists support a mixture of nature and nurture ideas.
Experiments, done in the 1930's by Lashley and Russell, had already looked into the development of depth perception. Lashley and Russel experimented on rats, some of which were raised in the dark, some in the light, inducing them to jump from one platform to another. The platforms were places at varying distances from the “jumping stand” the rats jumped from. Their results found that the rats, whether raised in the light or dark, jumped with a force closely correlated with distance, suggesting that depth perception in rats is innate. These findings were disputed however, due to the pre-training required to carry out the experiment.
Gibson and walked aimed to create an experiment to accurately and carefully investigate the development of depth perception in both human and non-human animals, whether this ability is innate and if not, how long it takes to develop and why. They believed that if it was innate it would be apparent by the time they could move independently.
