The Effects of Action Observation Therapy as a Rehabilitation Tool in Parkinson's Disease Patients: A Systematic Review.

Ioannis Giannakopoulos,Panagiotis Tsaklis,Charalambos Papaxanthis,Panagiota Karanika

doi:10.3390/ijerph19063311

Abstract

During Action Observation (AO), patients observe human movements that they then try to imitate physically. Until now, few studies have investigated the effectiveness of it in Parkinson’s disease (PD). However, due to the diversity of interventions, it is unclear how the dose and characteristics can affect its efficiency. We investigated the AO protocols used in PD, by discussing the intervention features and the outcome measures in relation to their efficacy. A search was conducted through MEDLINE, Scopus, Cochrane, and WoS until November 2021, for RCTs with AO interventions. Participant’s characteristics, treatment features, outcome measures, and main results were extracted from each study. Results were gathered into a quantitative synthesis (MD and 95% CI) for each time point. Seven studies were included in the review, with 227 participants and a mean PEDro score of 6.7. These studies reported positive effects of AO in PD patients, mainly on walking ability and typical motor signs of PD like freezing of gait. However, disagreements among authors exist, mainly due to the heterogeneity of the intervention features. In overall, AO improves functional abilities and motor control in PD patients, with the intervention dose and the characteristics of the stimulus playing a decisive role in its efficacy.

Highlights

Action observation (AO) therapy/training is based on the significant discovery of mirror neurons, initially found in the monkey cerebral cortex [1,2]
Agosta et al [38] found that immediately after the end of AO training (W4), participants reduced FoG severity and enhanced Unified Parkinson’s Disease Rating Scale (UPDRS)-III ON, Parkinson’s Disease Questionnaire-39 (PDQ-39), Berg Balance Scale (BBS), and 10 Meters Walking Test (10M-WT) scores, with improvements maintained until the follow up (W8), while the UPDRS-III ON score showed a trend towards a significant improvement at W8 in the AO group compared to the control group
Despite that there was no significant difference on the sit-to-walk times at any time point after training, the Centre of Pressure (COP) profiles showed significant differences between the two groups post-training, with patients in the AO enhancing the quality of COP profiles even 3 months post-intervention

Summary

Introduction

Action observation (AO) therapy/training is based on the significant discovery of mirror neurons, initially found in the monkey cerebral cortex [1,2]. It was observed that these neurons discharge, during the execution of goal-directed actions, and during the observation of the same actions performed by other macaques. The. MNS was found to be present in the human brain [3,4]. During AO, the excitability of the motor cortex is enhanced [5], and brain areas in the frontal and parietal lobes are recruited, to motor execution [6]. The MNS is involved in ‘’imitation” within a circuit, engaging the inferior parietal lobule, the inferior frontal gyrus, and the premotor cortex [7]. It is derived that the MNS is significantly exploited in humans during AO training [8].

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Results

Discussion

Conclusion