Manipulation of integration mechanisms under identical visual angle

The coherent processing of our environment requires the integration of local elements into a global gestalt. Among a number of principles that have been suggested by Gestalt psychologists to facilitate grouping mechanisms size and proximity appeared to be powerful features. At the present stage, it remains unclear if the integration of local elements into a global gestalt can be manipulated independently from its projection to the retina. To answer this question, we took advantage of the well known illusion that an object located far from an observer is perceived larger compared to the same object located at sho…