The contribution of peripheral visual information to visuospatial mapping prior to movement initiation

Abstract

Compensatory balance reactions impose tight temporal constraints to motor responses employed to re–capture stability. Vision is particularly important for compensatory reach–to–grasp reactions as locations of hand hold targets have varying inherent features and locations in 3D space, requiring precise motor commands in order to successfully contact the target. Internalizing a representation of the surrounding environment by creating a visuospatial map is possible means of circumventing temporal lags associated with using online visual feedback when performing compensatory reactions. Hand hold targets are often located in the peripheral visual field. This suggests an importance of mapping from the peripheral visual field and further suggests mapping of peripherally located targets may require the allocation of attentional resources in order to correctly encode their location. The purpose of this thesis was to examine the contribution of peripheral vision and associated attentional requirements of visuospatial mapping for rapid upper limb movements. Study 1 was designed to examine the influence of mapping with peripheral vision for compensatory reach–to–grasp reactions, specifically the influence of timing and location of visual information. Study 2 was designed to examine the potential effect a secondary visual attention task would have on mapping peripheral located targets prior to movement initiation. Overall the results from these studies show support for the ability to map peripherally located targets with peripheral visual feedback, and suggest that this mapping may be an automatic process. Findings from this thesis provide a basic insight into the incorporation of peripheral visual information into intrinsic visuospatial maps that provides a framework for future experiments into the understanding of how visuospatial maps are incorporated into compensatory balance reactions.