The effects of monocular viewing on hand-eye coordination during sequential grasping and placing movements

Abstract

The contribution of binocular vision to the performance of reaching and grasping movements has been examined previously using single reach-to-grasp movements. However, most of our daily activities consist of more complex action sequences, which require precise temporal linking between the gaze behaviour and manual action phases. Many previous studies found a stereotypical hand-eye coordination pattern, such that the eyes move prior to the reach initiation. Moving the eyes to the target object provides information about its features and location, which can facilitate the predictive control of reaching and grasping. This temporal coordination pattern has been established for the performance of sequential movements performed during binocular viewing. Here we manipulated viewing condition and examined the temporal hand-eye coordination pattern during the performance of a sequential reaching, grasping, and placement task. Fifteen participants were tested on a sequencing task while eye and hand movements were recorded binocularly using a video-based eyetracker and a motion capture system. Our results showed that monocular viewing disrupted the temporal coordination between the eyes and the hand during the place-to-reach transition phase. Specifically, the gaze shift was delayed during monocular compared to binocular viewing. The shift in gaze behaviour may be due to increased uncertainty associated with the performance of the placement task because of increased vergence error during monocular viewing, which was evident in all participants. These findings provide insight into the role of binocular vision in predictive control of sequential reaching and grasping movements.

Evaluation of the Leap Motion Controller during the performance of visually-guided upper limb movements

“…Placement time was defined from the end of reach-to-needle to the initiation of a reach away from the needle. These criteria are consistent with our previous work [ 19 , 20 ], as well as the aiming literature [ 6 , 32 , 33 ]. Because maximum grip aperture (MGA) is often used to assess grasping movements, MGA obtained from the Optotrak and the LMC systems was also compared during the bead-threading task.…”

Three-dimensional binocular eye–hand coordination in normal vision and with simulated visual impairment

“…Binocular vision and stereoscopic depth perception are fundamental in everyday eye–hand coordination (Fielder and Moseley 1996; O’Connor et al 2010; Gonzalez and Niechwiej-Szwedo 2016). Consequently, patients with stereovision deficits are known to have impairments in reaching and grasping hand movements [e.g., children with amblyopia (Grant et al 2014; Suttle et al 2011; Sloper et al 2011) or adults with age-related macular degeneration (Verghese et al 2016) or glaucoma (Kotecha et al 2009)].…”

Characteristic of Motor Control in Three-Dimensional Circular Tracking Movements during Monocular Vision

“…The increase of ω indicates that, during faster velocities, the subjects struggled to track the object accurately. During monocular vision, a delay in circular tracking movements can occur due to a gaze shift, as opposed to binocular vision where this effect is not as great, and therefore, Δ ω increases in line with the speed [25, 43]. Also, we can infer that Δ ω is larger in the ROT90 during monocular vision when the depth of the target cannot be accurately gauged [21].…”