Reaching and grasping in autism spectrum disorder: a review of recent literature

Abstract

Impairments in motor functioning, which, until recently, have rarely been a primary focus in autism spectrum disorder (ASD) research, may play a key role in the early expression of biological vulnerability and be associated with key social-communication deficits. This review summarizes current knowledge of motor behavior in ASD, focusing specifically on reaching and grasping. Convergent data across the lifespan indicate that impairments to reaching and grasping emerge early in life, affect the planning and execution of motor programs, and may be impacted by additional impairments to sensory control of motor behavior. The relationship between motor impairments and diagnostic outcomes will be discussed.

Keywords: autism spectrum disorder; motor execution; motor planning; movement; reach-to-grasp; reaching; review.

Figure 1

Framework of review. A movement is planned and then executed. The executed movement is monitored, as online corrections aide ongoing movements and offline corrections aide the planning of subsequent movements.

Figure 2

Experimental design of the underhand grasps used in Hughes (17). (A) The rod and ring set-up; (B) example of a comfortable end-state underhand grasp; (C) example of an uncomfortable end-state underhand grasp. Note that the rod is positioned the same for each trial, only the color of the end of the rod to be placed in the ring differs between trials [adapted from Ref. (17)].

Figure 3

Example of the cueing used by Stoit et al. (51). (A) Pointing cue to indicate cylinder to be grasped (left or right); (B) hand shape cue to indicate cylinder to be grasped (precision or power).