Global representations of occluded objects hinder priming effects of local interpolations in a complex matching prime paradigm.

Abstract

In this study, we explore the type of representations that observers have about surfaces that are partially occluded.  When a surface is partially occluded, we can have a theoretically infinite number of representations for that surface.  Most prominent are local (based on local good continuation of the intersecting edges) and global (based on the Pragnanz principle and stimulus symmetry) representations and both have been shown to exist in our cognitive system.

We employed a priming matching paradigm (van Lier, van der Helm & Leeuwenberg, 1995) but added more objects to the series of surfaces used in the trials.  Observers had to respond quickly to a pair of stimuli (same/different response) that followed a brief presentation of a prime stimulus of several types (local, global, etc.).

Our data show that there was no priming effect for either category of primes unlike the original study, but that the global category of stimuli was processed faster than the other categories.  We take these results to suggest that in complex stimulus environments, “primes” may not be good facilitators, and that the visual system completes the task at hand based on core global representations.