Pixel asymmetry predicts between-object differences in the object-based compatibility effect

Abstract

When participants make left/right responses to unimanually graspable objects, response times (RTs) are faster when the responding hand is aligned with the viewed object's handle. This object-based compatibility effect (CE) is often attributed to motor activation elicited by the object's afforded grasp. However, some evidence suggests that the object-based CE is an example of spatial CEs, or Simon effects, elicited by the protruding nature of objects' handles. Moreover, recent work shows that the way in which objects are centred on-screen might attenuate or reverse CEs, perhaps due to differences in pixel asymmetry (the proportion of pixels either side of fixation) between centralities. In th..