Spatial Biases in Perception and Cognition

What is a spatial bias? This can be most easily understood if we consider each of the words in the term. First, “spatial” refers to configurations of or distances between objects in the environment. Its use in the term “spatial bias” fits our everyday conception of what we mean by “space,” but also goes considerably beyond our everyday conception to include stimuli that might not initially be considered spatial. For example, we might think of different auditory pitches as being located in an auditory space (e.g., height on a musical staff ) or different numerical quantities as providing a framework for mapping space (e.g., reflecting different extents or different coordinates in a graph). Second, “bias” refers to aconsistent pattern of perceptual judgment or motor action. In some cases, there might be a consistent direction of error in judgment or action away from the veridical response (e.g., as when observers consistently overshoot the actual final location of a moving target in their judgment of the final location); in other cases, there might be a consistent pattern of judgment or action in the absence of a clear veridical response (e.g., associating higher auditory pitches with higher locations in the picture plane). Thus, a “spatial bias” is a consistent pattern of perceptual or cognitive judgments or motor actions involving configuration or distance in response to a stimulus when those judgments or actions do not correspond to the veridical stimulus or when there is no clear veridical stimulus to compare with those judgments or actions.