Amodal perception

Overview
Amodal perception is the term used to describe the full perception of a physical structure when it is only partially perceived. For example, a table will be perceived as a complete volumetric structure even if only part of it is visible; the internal volumes and hidden rear surfaces are perceived despite the fact that only the near surfaces are exposed to view, and the world around us is perceived as a surrounding void, even though only part of it is in view at any time.

Formulation of the theory is credited to the Belgian psychologist Albert Michotte and Fabio Metelli, an Italian psychologist, with their work developed in recent years by E.S. Reed and the Gestaltists.

Modal completion is a similar phenomena in which a shape is perceived to be occluding other shapes even when the shape itself is not drawn. Examples include the triangle that appears to be occluding three disks in the Kanizsa triangle and the circles and squares that appear in different versions of the Koffka cross.