The utility of different object properties in change detection

Previous research has shown that changes to the configuration

of an object’s parts are better detected than changes to the

shape/arrangement of those parts. This finding suggests that

configural, rather than shape, information plays a critical role

in object change detection. The current study investigated

configural and shape changes in greater detail to determine

what aspects of these two types of object properties, if any,

were more or less important for change detection. Specifically

we investigated configural changes in terms of the orientation

of the part change and shape changes in terms of the nonaccidental

properties of the part change. Using a one-shot

change detection task with a single object display, we

manipulated: (i) the orientation of a configuration change (0º,

90º or 180º) and (ii) both the number and the type of nonaccidental

object properties (NAPs) involved in each shape

change (3 NAPs were manipulated in total: curvature of axis,

curvature of edges, and constancy of size). We found that

changes to the curvature of the axis were better detected than

changes to either the curvature of edges or to the constancy of

size. Detection accuracy was better when there were more

NAPs involved in a change. Configural changes involving

180º were more accurately detected than changes involving

either 0º or 90º. These results suggest that the axes and basic

layout of parts is critical information in change detection.

Implications for theories of object recognition are discussed.