Influence of Perspective of Action Observation Training on Residual Limb Control in Naïve Prosthesis Usage

Abstract

Prior work in amputees and partial limb immobilization have shown improved neural and behavioral outcomes in using their residual limb with prosthesis when undergoing observationbased training with a prosthesis-using actor compared to an intact limb. It was posited that these improvements are due to an alignment of user with the actor. It may be affected by visual angles that allow emphasis of critical joint actions which may promote behavioral changes. The purpose of this study was to examine how viewing perspective of observation-based training effects prosthesis adaptation in naïve device users. Twenty non-amputated prosthesis users (NAPUs) learned how to use an upper extremity prosthetic device while viewing a training video from either a sagittal or coronal perspective. These views were chosen as they place visual emphasis on different aspects of task performance to the device. We found that perspective of actions has a significant role in adaptation of the residual limb while using upper limb prostheses. Perspectives that demonstrate elbow adaptations to prosthesis usage may enhance the functional motor outcomes of action observation therapy. This work has potential implications on how prosthetic device operation is conveyed to persons adapting to prostheses through action observation based therapy.

Efficacy and Characteristics of the Stimuli of Action Observation Therapy in Subjects With Parkinson's Disease: A Systematic Review

“…It is worth underlining that MNS activity during AOT also seems to be influenced by empathy of observers, which is the ability to understand and perceive what another person is experiencing ( 53 , 54 ). Additionally, studies reported that, not only person-related perspective, but also viewing perspective represent a potential influencing factor on AOT efficacy ( 55 ). In particular, observing actions from a perspective that emphasizes motor details seems to improve motor imitation.…”

“…In the studies of this review, where AOT was proposed to patients with PD, stimuli showed actions performed by healthy subjects, except for the study of Jaywant et al ( 19 ) which included also patients with PD. Although the use of video-clips representing patients with the same pathological conditions of observers revealed positive results in terms of MNS recruitment in prosthesis users, no studies have investigated the effects of this stimuli characteristics in patients with neurological disorders ( 55 , 72 ). However, the use of subjects with the same clinical condition as the observers could be limited due to the difficulty in reproducing the features of pathological movements and the need to overcome their motor impairments through AOT stimuli.…”

Implicit development of gaze strategies support motor improvements during action encoding training of prosthesis use

“…We sought to identify a potential mechanism that could explain neuromotor benefits of matched over mismatched limb training for prosthesis users seen in prior studies [13][14][15] with eye movements as the primary outcome of interest. Findings reveal that gaze patterns significantly differentiate matched versus mismatched trained groups.…”

“…A recent longitudinal training study showed increased neural activation in parietofrontal areas and improved motor performance for matched limb training compared to mismatched training 15 . Further, we have identified improved kinematic outcomes, such as decrease in shoulder motion variability along with greater novel elbow motion variability, to matched limb training compared to mismatched limb training 13,14 . Thus, participants in the mismatched observation mimic the motor patterns of an intact person while matched observation promoted the generation of new movement patterns that is more efficient for prosthesis use 13 .…”

“…Research reveals that gaze of body cues can support understanding action intent in others 19,20 which could be beneficial to understanding of action observation-based rehabilitation outcomes 21 . We postulate that the neurobehavioral improvements seen in matched limb over mismatched limb training [13][14][15] are initially driven by implicitly divergent gaze strategies between the two training approaches.…”