Causal contraction: spatial binding in the perception of collision events.

Causality is a higher-level mental construct derived from low-level percepts such as contiguity in space-time. We show that low-level spatial perception is distorted by the presence of a causal connection, such that two objects appear closer in space when they are causally linked than when they are not. This finding parallels recent demonstrations of temporal causal binding and suggests that causality is at the root of a general ambiguity-resolution process operating on the human perceptual system.