Interactions between dorsal and ventral streams for controlling skilled grasp

Vonne Van Polanen,Marco Davare

doi:10.1016/j.neuropsychologia.2015.07.010

Abstract

The two visual systems hypothesis suggests processing of visual information into two distinct routes in the brain: a dorsal stream for the control of actions and a ventral stream for the identification of objects. Recently, increasing evidence has shown that the dorsal and ventral streams are not strictly independent, but do interact with each other. In this paper, we argue that the interactions between dorsal and ventral streams are important for controlling complex object-oriented hand movements, especially skilled grasp. Anatomical studies have reported the existence of direct connections between dorsal and ventral stream areas. These physiological interconnections appear to be gradually more active as the precision demands of the grasp become higher. It is hypothesised that the dorsal stream needs to retrieve detailed information about object identity, stored in ventral stream areas, when the object properties require complex fine-tuning of the grasp. In turn, the ventral stream might receive up to date grasp-related information from dorsal stream areas to refine the object internal representation. Future research will provide direct evidence for which specific areas of the two streams interact, the timing of their interactions and in which behavioural context they occur.

Highlights

The two visual systems hypothesis suggests processing of visual information into two distinct routes in the brain: a dorsal stream for the control of actions and a ventral stream for the identification of objects
Since the introduction of the dual-stream theory, many studies have confirmed and disproved hypotheses of this theory. It is not the scope of this paper to provide an extended review of the literature, as others have provided such overviews (Cloutman, 2013; Grafton, 2010; Milner and Goodale, 2008)
This paper proposes that these interactions might be especially important for complex object-oriented hand movements, such as skilled grasp

Summary

Introduction

While dorsomedial regions classically contribute to the planning of reaching movements (Davare et al, 2015; Davare et al, 2012; Vesia and Crawford, 2012), dorsolateral areas integrate grasp-related information (Davare et al, 2007; Davare et al, 2010; Tunik et al, 2005). These two subcircuits have been found to interact depending on the degree of online control required by the action (Grol et al, 2007; Verhagen et al, 2013). The context in which the object is grasped plays a role, for instance in the use of tools or when the same object can be used for different applications

Anatomical connections between dorsal and ventral streams

Behavioural studies in patients and healthy subjects

Interactions between dorsal and ventral stream subserve skilled grasp

Conclusions