Representation of object continuity in the visual cortex.

An amazing feature of our visual system is the ability to detect and track objects in the stream of continually changing retinal images. Theories have proposed that the system creates temporary internal representations that persist across changing images, providing continuity. However, how such representations are formed in the brain is not known. Here we examined the time course of the responses of border-ownership-selective neurons in the visual cortex to displays that portray object continuity. We found that the neurons signal border ownership immediately when new objects appear, but when a border that has been assigned to one object is reassigned to another object while the first remains in the display, the initial responses persist. The neurons continue to signal the initial assignment despite the presence of contradicting figure--ground cues. We propose that border ownership selectivity reflects mechanisms that create object continuity.