PREATTENTIVE PERCEPTION OF ELEMENTARY 3-DIMENSIONAL SHAPES

Experiments in which a single target pattern is discriminated from mul tiple background distracters show that certain shaded, two-dimensional (2-D) stimuli consistent with a top-lit, polyhedral interpretation ca n be processed fast (<80 msec) and in parallel. Unshaded line drawings of the same shapes, however, are processed serially. Strong pop-out a symmetries and control experiments involving shaded patterns that do n ot have familiar 3-D interpretations suggest that such fast, parallel processing is dependent upon perception of 3-D shape. Furthermore, thi s process can be influenced by contextual scene information, in a mann er that is dependent upon whether the additional cues contribute to th e perception of a consistent 3-D scene. Copyright (C) 1996 Elsevier Sc ience Ltd.