Amodal Completion Revisited.

Walter Gerbino

doi:10.1177/2041669520937323

Abstract

Amodal completion (AC) is analyzed, by looking at its historical roots and persisting conceptual difficulties. Looking at the origin of the concept, it becomes clear that it is not equivalent to perception of occluded parts. The role of fragment incompleteness is discussed, to clarify that it cannot be taken as a necessary factor for eliciting AC. The standard view of AC, depicted as a set of processes that extrapolate from veridically represented image fragments, is evaluated and rejected on the basis of evidence that AC modifies also modal parts. The theoretical importance of AC phenomena and their potential to reveal the inner forces of perceptual organization are emphasized, with specific reference to the minimum principle. Instances in which AC might be expected but does not occur are examined, to define the limits of such an integrative process.

Highlights

Amodal completion (AC) is analyzed, by looking at its historical roots and persisting conceptual difficulties
Amodal completion (AC) has grown in interest—as demonstrated by this special issue of i-Perception—but has kept the enigmatic nature that marked its official birth in the scientific literature (Michotte & Burke, 1951/1962), possibly because of persisting ambiguities in its definition and the intrinsic vagueness of phenomena grouped under its umbrella
Some computational models embody AC processes (Follman et al, 2018; Oliver et al, 2016; Zhu et al, 2017), while occasional references to AC are found in the broader literature on object recovery from images with missing regions, not necessarily due to occlusion (Ehsani et al, 2017; Guo et al, 2018; Han et al, 2017; Harary et al, 2014; Hueting et al, 2017; Li & Malik, 2016; Mavridis et al, 2015; Oliver et al, 2017; Perez et al, 2016; Shao et al, 2014)

Summary

Introduction

Amodal completion (AC) is analyzed, by looking at its historical roots and persisting conceptual difficulties. Michotte and Burke (1951/1962) discussed two paradigmatic instances of amodal presence: the tunnel effect (involving the continuous presence of a moving object behind a screen, when only the entry and exit motion segments are modally visible) and the perceived back of opaque solid bodies (involving the colorless continuation of the front surface into the occluded space).

Results

Conclusion