Plasticity and modular control of locomotor patterns in neurological disorders with motor deficits

Ivanenko, Yuri P.; Cappellini, Germana; Солопова, И. А.; Гришин, А. М.; MacLellan, Michael J.; Poppele, R. E.; Lacquaniti, Francesco

doi:10.3389/fncom.2013.00123

Cited by 43 publications

(37 citation statements)

References 94 publications

(143 reference statements)

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“…Tens of muscles participate in the control of limb and body movements during locomotion, and redundancy in the neuromuscular system is an essential element of gait adaptability (Winter, 1989; Cai et al, 2006; Noble and Prentice, 2006; Molinari, 2009; Duysens et al, 2013; Ivanenko et al, 2013). Due to muscle redundancy, various neuromotor strategies may exist to compensate for decreased muscle strength and pathology (Grasso et al, 2004; Goldberg and Neptune, 2007; Huang and Ferris, 2012; Gordon et al, 2013).…”

Section: Discussionmentioning

confidence: 99%

EMG patterns during assisted walking in the exoskeleton

Sylos-Labini

Scaleia

d’Avella

et al. 2014

Front. Hum. Neurosci.

113

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Neuroprosthetic technology and robotic exoskeletons are being developed to facilitate stepping, reduce muscle efforts, and promote motor recovery. Nevertheless, the guidance forces of an exoskeleton may influence the sensory inputs, sensorimotor interactions and resulting muscle activity patterns during stepping. The aim of this study was to report the muscle activation patterns in a sample of intact and injured subjects while walking with a robotic exoskeleton and, in particular, to quantify the level of muscle activity during assisted gait. We recorded electromyographic (EMG) activity of different leg and arm muscles during overground walking in an exoskeleton in six healthy individuals and four spinal cord injury (SCI) participants. In SCI patients, EMG activity of the upper limb muscles was augmented while activation of leg muscles was typically small. Contrary to our expectations, however, in neurologically intact subjects, EMG activity of leg muscles was similar or even larger during exoskeleton-assisted walking compared to normal overground walking. In addition, significant variations in the EMG waveforms were found across different walking conditions. The most variable pattern was observed in the hamstring muscles. Overall, the results are consistent with a non-linear reorganization of the locomotor output when using the robotic stepping devices. The findings may contribute to our understanding of human-machine interactions and adaptation of locomotor activity patterns.

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Section: Discussionmentioning

confidence: 99%

EMG patterns during assisted walking in the exoskeleton

Sylos-Labini

Scaleia

d’Avella

et al. 2014

Front. Hum. Neurosci.

113

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“…For instance, in amputees, the occurrence of the heel strike transient is evident on the sound side while the prosthetic limb exhibits smooth loading, presumably due to a lack of active push-off from the prosthetic feet in late stance and/or reduced energy storage and return from the prosthetic feet (Klodd et al, 2010). Nevertheless, the weakness of distal extensors does not inevitably result in the abnormal GRF transient since it was not observed in peripheral neuropathy (Ivanenko et al, 2013a). Further experiments are needed to understand better its biomechanical nature.…”

Section: Foot Loading In Camentioning

confidence: 99%

“…into account the ability of the central nervous system to adapt when faced with a specific gait pathology, often it is difficult to distinguish what primarily comes from pathology and what comes from compensatory mechanisms (Dietz, 2002;Grasso et al, 2004;Ivanenko et al, 2013a). The observed widening of EMG bursts (Fig.…”

Section: Muscle Activation Patterns In Cerebellar Ataxiamentioning

confidence: 99%

Locomotor patterns in cerebellar ataxia

Martino

Ivanenko

Serrao

et al. 2014

Journal of Neurophysiology

Self Cite

118

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Several studies have demonstrated how cerebellar ataxia (CA) affects gait, resulting in deficits in multijoint coordination and stability. Nevertheless, how lesions of cerebellum influence the locomotor muscle pattern generation is still unclear. To better understand the effects of CA on locomotor output, here we investigated the idiosyncratic features of the spatiotemporal structure of leg muscle activity and impairments in the biomechanics of CA gait. To this end, we recorded the electromyographic (EMG) activity of 12 unilateral lower limb muscles and analyzed kinematic and kinetic parameters of 19 ataxic patients and 20 age-matched healthy subjects during overground walking. Neuromuscular control of gait in CA was characterized by a considerable widening of EMG bursts and significant temporal shifts in the center of activity due to overall enhanced muscle activation between late swing and mid-stance. Patients also demonstrated significant changes in the intersegmental coordination, an abnormal transient in the vertical ground reaction force and instability of limb loading at heel strike. The observed abnormalities in EMG patterns and foot loading correlated with the severity of pathology [International Cooperative Ataxia Rating Scale (ICARS), a clinical ataxia scale] and the changes in the biomechanical output. The findings provide new insights into the physiological role of cerebellum in optimizing the duration of muscle activity bursts and the control of appropriate foot loading during locomotion.

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“…The idea of plasticity and modular control of locomotor patterns [9] could be useful for further interpretations.…”

Section: Discussionmentioning

confidence: 99%