Objective measurement of gestalts: Quantifying grouping effect by tilt aftereffect.

The importance of holistic perception is described by Gestalt psychology and its principles. Gestalt psychologists have promoted a formal and testable framework for these principles. Quantitative measurements have been introduced from Gestalt psychology in order to complement traditional phenomenal descriptions. Here we demonstrated a new method of measuring grouping effects objectively and quantitatively, by means of tilt aftereffect (TAE) from visual adaptation. Experiment 1 validated the method by measuring grouping based on either proximity or color similarity. Experiments 2 and 3 verified that this paradigm is also effective with dimotif lattices in which different perceptual organizations compete. The novel TAE-based paradigm is an objective and effective method for studying perceptual organization, especially the relationship between different Gestalt principles.