Coding of Far and Near Space in Neglect Patients

Abstract

Far (extrapersonal) and near (peripersonal) spaces are behaviorally defined as the space outside arm-reaching distance and the space within arm-reaching distance. Animal and human studies have shown that this behavioral distinction corresponds in the brain to a composite neural architecture for space representation. In this paper we discuss how the activation of the neural correlates of far and near space can be modulated by the use of tools that change the effective spatial relationship between the agent's body and the target object. When subjects reach for a far object with a tool, it is possible to show that far space is remapped as near. We shall also argue that space remapping may not occur when far space is reached by walking instead of using a tool.