Binocular Invariants in Interceptive Tasks: A Directed Perception Approach

While the perceptual substratum of interceptive tasks has been largely investigated, no studies report unequivocal evidence for the use of a specific source of information. This result can be interpreted differently according to the perceptual theory considered. In the framework of directed perception this result would illustrate the flexibility of our perceptual system performing the same task in different ways under different circumstances. This paper is designed to formalise, for each category of invariant considered (ie temporal, spatial, and spatiotemporal), a binocular invariant leading to specification of the same physical quantity as a monocular invariant identified in the literature. This formalisation illustrates a redundancy of monocular and binocular invariants that is particularly appealing from the viewpoint of directed perception.