Coordination of Eye and Hand for Aimed Limb Movements

This chapter discusses the nature of the information that the eyes can provide that might be used to guide limb movements. This chapter discusses the several features of limb movements that might yield some insight into how the information provided by the eye may actually be used and presents the results of three experiments designed to address different questions about the relation between eye and hand. The role of the various types of visual information provided by the eyes (e.g., vision of the moving limb or of the target for the movement) and the role of eye movements in enhancing nonvisual information that could be useful in guiding limb movements are discussed. There are two distinct types of information that can be obtained from the eyes for use in controlling limb movements: retinal and extraretinal. Retinal information includes information obtained from the patterns of stimulation on the retina regarding the location and movement of the limb and of the target for a movement. Extraretinal information includes information about the movement and position of the eyes obtained from nonretinal sources.