Global scene layout modulates contextual learning in change detection

Markus Conci,Hermann J Müller

doi:10.3389/fpsyg.2014.00089

Abstract

Change in the visual scene often goes unnoticed – a phenomenon referred to as “change blindness.” This study examined whether the hierarchical structure, i.e., the global–local layout of a scene can influence performance in a one-shot change detection paradigm. To this end, natural scenes of a laid breakfast table were presented, and observers were asked to locate the onset of a new local object. Importantly, the global structure of the scene was manipulated by varying the relations among objects in the scene layouts. The very same items were either presented as global-congruent (typical) layouts or as global-incongruent (random) arrangements. Change blindness was less severe for congruent than for incongruent displays, and this congruency benefit increased with the duration of the experiment. These findings show that global layouts are learned, supporting detection of local changes with enhanced efficiency. However, performance was not affected by scene congruency in a subsequent control experiment that required observers to localize a static discontinuity (i.e., an object that was missing from the repeated layouts). Our results thus show that learning of the global layout is particularly linked to the local objects. Taken together, our results reveal an effect of “global precedence” in natural scenes. We suggest that relational properties within the hierarchy of a natural scene are governed, in particular, by global image analysis, reducing change blindness for local objects through scene learning.

Highlights

Complex natural environments require the visual system to provide structure to the visual input, integrating fragmentary parts into coherent objects that are segregated from the background and other objects
This analysis shows that global congruent scene layouts attenuated change blindness
GENERAL DISCUSSION The present study examined whether the global layout, provided by the relational structure of a natural scene, can influence change blindness

Summary

Introduction

Complex natural environments require the visual system to provide structure to the visual input, integrating fragmentary parts into coherent objects that are segregated from the background and other objects. Similar hierarchical relations have been demonstrated for a variety of composite figures that require global- and local-level structural elements to be integrated (see, e.g., Hübner and Volberg, 2005). The Navon letter (Navon, 1977) depicted in Figure 1A consists of an arrangement of the local letters “H,” which combine to form the global letter “U.” Kanizsa figures (Kanizsa, 1976) comprise a local arrangement of circular inducers, which yield the impression of a salient, global square shape (Figure 1B). Comparable relationships can emerge from other hierarchical shape stimuli, were, for instance, local squares combine to form a global triangle (Figure 1C; Kimchi and Palmer, 1982)

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