Functional actions of hands and tools influence attention in peripersonal space

Abstract

Abstract Human perceptual and attentional systems operate to help us perform functional and adaptive actions in the world around us. In this review, we consider different regions of peripersonal space—peri-hand space, reachable space, and tool space when used in both peri- and extrapersonal space. Focusing on behavioural and electrophysiology/event-related potentials (EEG/ERP) studies using comparable target detection paradigms, we examine how visuospatial attention is facilitated or differentiated due to the current proximity and functional capabilities of our hands and the tools we hold in them. The functionality of the hand and tool is defined by the action goals of the user and the available functional affordances or parts available to achieve the goals. Finally, we report recent tool-use studies examining how the distribution of attention to tool space can change as a result of tool functionality and directional action crossing peripersonal and extrapersonal space boundaries. We propose that the functional capabilities of the hand and tools direct attention to action-relevant regions of peripersonal space. Although neural mechanisms such as bimodal neurons may enhance the processing of visual information presented in near-hand regions of peripersonal space, functional experience and the relevance of the space for upcoming actions more strongly direct attention within regions of peripersonal space. And, while some aspects of functionality can be extended into extrapersonal space, the multimodal nature of peripersonal space allows it to be more modifiable in the service of action.