Functional Correlates of Action Observation of Gait in Patients with Parkinson’s Disease

Abstract

Background. Action observation (AO) relies on the mirror neuron system (MNS) and has been proposed as a rehabilitation tool in Parkinson’s disease (PD), in particular for gait disorder such as freezing of gait (FOG). In this study, we aimed to explore the brain functional correlates of the observation of human gait in PD patients with (FOG+) and without (FOG-) FOG and to investigate a possible relationship between AO-induced brain activation and gait performance. Methods. Fifty-four participants were enrolled in the study (15 PD FOG+; 18 PD FOG-; 21 healthy subjects (HS)) which consisted of two tasks in two separate days: (i) gait assessment and (ii) task-fMRI during AO of gait. Differences between patients with PD (FOG+ and FOG-) and HS were assessed at the level of behavioral and functional analysis. Results. Gait parameters, including gait velocity, stride length, and their coefficients of variability (CV), were different in PD patients compared to HS, whereas gait performance was similar between FOG+ and FOG-. The PD group, compared to HS, presented reduced functional activation in the frontal, cingulum, and parietooccipital regions. Reduced activity was more pronounced in the FOG+ group, compared to both HS and FOG- groups. Gait variability positively correlated with precuneus neural activity in the FOG+ group. Discussion. Patients with PD present a reduced functional activity during AO of gait, especially if FOG+. A baseline knowledge of the neural correlates of AO of gait in the clinical routine “on” status would help for the design of future AO rehabilitative interventions.

Gait-Related Brain Activation During Motor Imagery of Complex and Simple Ambulation in Parkinson's Disease With Freezing of Gait

“…In particular, the activity of bilateral SMA and right frontal and right superior temporal lobules in PD NOFOG decreased compared with normal controls during normal gait MI. These findings are consistent with the results of an action observation fMRI study of normal walking in PD (Bommarito et al, 2020 ). From the physiological point of view, the SMA and premotor cortex have a tight connection to the spinal cord and brainstem reticular formation, including the pedunculopontine nucleus (PPN) area and MLR (Aravamuthan et al, 2009 ).…”

“…It could not simply be explained by a single gait parameter or the activity in one single brain region. A recent study illustrated that gait variability of stride length and walking velocity positively correlated with precuneus neural activity in PD FOG (Bommarito et al, 2020 ). The finding charged a new possibility for exploiting the relationship among the sophisticated FOG brain activities and gait parameters in the future.…”

Early modulations of neural oscillations during the processing of emotional body language

“…Indeed, these oscillations have shown sensitivity both to action observation and EBL. In particular, the mu rhythm – a well‐known oscillation in the alpha band (i.e., 8–13 Hz) recorded over central sensors – shows a consistent ERD during action execution and observation (Bommarito et al, 2020; Debnath et al, 2019; Oberman et al, 2005; Pineda, 2005). This activity reflects motor resonance, i.e., the mapping of observed motor actions onto one's motor representations – a phenomenon occurring later than the early freezing response to EBL (Borgomaneri et al, 2015a; Spaccasassi et al, 2022).…”

Effects of movement congruence on motor resonance in early Parkinson’s disease

“…The observation of action seems to involve the generation of the internal representation of that same action in the observer, a process named Motor Resonance (MR) 1 , 2 . Importantly, action observation determines the activation of different networks located in the visual, motor, and perceptive areas 3 .…”

“…People with Parkinson's disease appear to have a slowdown in the form of motor learning, probably due to impairment in executive functions 6 . Recent neuroimaging studies reported a defect in brain areas during observation of gait in Parkinson’s disease patients 3 . The basal dysfunction of PD may play a role in the functioning of motor resonance mechanisms.…”