What experiment provides evidence of depth perception in infants?

The visual cliff experiment is a key study in understanding depth perception in infants. Conducted by Eleanor J. Gibson and Richard D. Walk in the 1960s, the study presented infants with a platform that had a clear drop-off on one side, creating the illusion of a cliff. The infants, typically around six to twelve months old, were placed on this platform, which featured a patterned surface on the "shallow" side and a clear drop on the "deep" side.

The critical observation was that most infants would hesitate to crawl over the "cliff" side, indicating that they had developed a sense of depth perception. This behavior suggests that even at a young age, infants are capable of interpreting visual cues to navigate their environment safely. The results of the visual cliff experiment demonstrated that depth perception is innate and begins to develop in the early stages of life, as infants can discern dangerous situations even if they have not had prior experiences of falling.

In contrast, other options, such as the A-not-B task, the marshmallow test, and the strange situation, pertain to different developmental concepts, such as object permanence, impulse control, and attachment styles, respectively. These do not specifically focus on the development of depth perception, making