Explaining Parkinsonian postural sway variabilities using intermittent control theory

Postural impairment due to neuro-degenerative disorders such as Parkinson’s Disease (PD) leads to restricted gait patterns, fall-related injuries, decreased mobility, and loss of functional independence. Though several clinical and posturographic studies have attempted to reveal the complex pathophy...

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Vydáno v:	Journal of biomechanics Ročník 105; s. 109791
Hlavní autoři:	Dash, Ranjita, Shah, Vrutangkumar V., Palanthandalam-Madapusi, Harish J.
Médium:	Journal Article
Jazyk:	angličtina
Vydáno:	United States Elsevier Ltd 22.05.2020 Elsevier Limited
Témata:	Active control Ankle Basal ganglia Center of pressure Central nervous system diseases Computer simulation Control stability Control theory Disease Progression Energy efficiency Feedback control Gait Human quiet stance Humans Intermittent control Movement disorders Neurodegenerative diseases Noise Parkinson Disease Parkinson's disease Pilot Projects Postural Balance Posture Strategy Center of pressure Intermittent control Human quiet stance Parkinson’s disease
ISSN:	0021-9290, 1873-2380, 1873-2380
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Abstract	Postural impairment due to neuro-degenerative disorders such as Parkinson’s Disease (PD) leads to restricted gait patterns, fall-related injuries, decreased mobility, and loss of functional independence. Though several clinical and posturographic studies have attempted to reveal the complex pathophysiology involved in PD, the diversity of Parkinsonian population makes them unclear and sometimes even contradictory. For instance, studies related to the Center of Pressure (CoP) sway during quiet stance in PD patients highlight both increase and reduction of magnitude in contrast to age-matched healthy individuals. A possible explanation for this contradiction is presented in this article. While the presence of intermittent control has been observed in postural control in human quiet stance, we hypothesize that one of the factors that affects postural instability in PD might be the increase in intermittency in active feedback control. Using a simulation model representing the Anterior-Posterior dynamics of human quiet standing, the intermittent control strategy is first contrasted against continuous control strategy in terms of stability, energy efficiency and settling time, thus establishing the inherent advantages of an intermittent control strategy. Further, the ability of the intermittent control strategy to explain several clinical observations in PD is demonstrated. An experimental pilot study is also conducted to support the simulation study, and several body sway parameters derived from recordings of CoP are presented. The presented results are in close agreement with reported clinical observations and may also prove useful for the assessment of disease progression and future fall risk.
AbstractList	Postural impairment due to neuro-degenerative disorders such as Parkinson's Disease (PD) leads to restricted gait patterns, fall-related injuries, decreased mobility, and loss of functional independence. Though several clinical and posturographic studies have attempted to reveal the complex pathophysiology involved in PD, the diversity of Parkinsonian population makes them unclear and sometimes even contradictory. For instance, studies related to the Center of Pressure (CoP) sway during quiet stance in PD patients highlight both increase and reduction of magnitude in contrast to age-matched healthy individuals. A possible explanation for this contradiction is presented in this article. While the presence of intermittent control has been observed in postural control in human quiet stance, we hypothesize that one of the factors that affects postural instability in PD might be the increase in intermittency in active feedback control. Using a simulation model representing the Anterior-Posterior dynamics of human quiet standing, the intermittent control strategy is first contrasted against continuous control strategy in terms of stability, energy efficiency and settling time, thus establishing the inherent advantages of an intermittent control strategy. Further, the ability of the intermittent control strategy to explain several clinical observations in PD is demonstrated. An experimental pilot study is also conducted to support the simulation study, and several body sway parameters derived from recordings of CoP are presented. The presented results are in close agreement with reported clinical observations and may also prove useful for the assessment of disease progression and future fall risk. Postural impairment due to neuro-degenerative disorders such as Parkinson's Disease (PD) leads to restricted gait patterns, fall-related injuries, decreased mobility, and loss of functional independence. Though several clinical and posturographic studies have attempted to reveal the complex pathophysiology involved in PD, the diversity of Parkinsonian population makes them unclear and sometimes even contradictory. For instance, studies related to the Center of Pressure (CoP) sway during quiet stance in PD patients highlight both increase and reduction of magnitude in contrast to age-matched healthy individuals. A possible explanation for this contradiction is presented in this article. While the presence of intermittent control has been observed in postural control in human quiet stance, we hypothesize that one of the factors that affects postural instability in PD might be the increase in intermittency in active feedback control. Using a simulation model representing the Anterior-Posterior dynamics of human quiet standing, the intermittent control strategy is first contrasted against continuous control strategy in terms of stability, energy efficiency and settling time, thus establishing the inherent advantages of an intermittent control strategy. Further, the ability of the intermittent control strategy to explain several clinical observations in PD is demonstrated. An experimental pilot study is also conducted to support the simulation study, and several body sway parameters derived from recordings of CoP are presented. The presented results are in close agreement with reported clinical observations and may also prove useful for the assessment of disease progression and future fall risk.Postural impairment due to neuro-degenerative disorders such as Parkinson's Disease (PD) leads to restricted gait patterns, fall-related injuries, decreased mobility, and loss of functional independence. Though several clinical and posturographic studies have attempted to reveal the complex pathophysiology involved in PD, the diversity of Parkinsonian population makes them unclear and sometimes even contradictory. For instance, studies related to the Center of Pressure (CoP) sway during quiet stance in PD patients highlight both increase and reduction of magnitude in contrast to age-matched healthy individuals. A possible explanation for this contradiction is presented in this article. While the presence of intermittent control has been observed in postural control in human quiet stance, we hypothesize that one of the factors that affects postural instability in PD might be the increase in intermittency in active feedback control. Using a simulation model representing the Anterior-Posterior dynamics of human quiet standing, the intermittent control strategy is first contrasted against continuous control strategy in terms of stability, energy efficiency and settling time, thus establishing the inherent advantages of an intermittent control strategy. Further, the ability of the intermittent control strategy to explain several clinical observations in PD is demonstrated. An experimental pilot study is also conducted to support the simulation study, and several body sway parameters derived from recordings of CoP are presented. The presented results are in close agreement with reported clinical observations and may also prove useful for the assessment of disease progression and future fall risk.
ArticleNumber	109791
Author	Shah, Vrutangkumar V. Palanthandalam-Madapusi, Harish J. Dash, Ranjita
Author_xml	– sequence: 1 givenname: Ranjita surname: Dash fullname: Dash, Ranjita organization: SysIDEA Lab, Mechanical Engineering, Indian Institute of Technology Gandhinagar, India – sequence: 2 givenname: Vrutangkumar V. surname: Shah fullname: Shah, Vrutangkumar V. organization: SysIDEA Lab, Mechanical Engineering, Indian Institute of Technology Gandhinagar, India – sequence: 3 givenname: Harish J. surname: Palanthandalam-Madapusi fullname: Palanthandalam-Madapusi, Harish J. email: harish@iitgn.ac.in organization: SysIDEA Lab, Mechanical Engineering, Indian Institute of Technology Gandhinagar, India
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Keywords	Center of pressure Intermittent control Human quiet stance Parkinson’s disease
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Snippet	Postural impairment due to neuro-degenerative disorders such as Parkinson’s Disease (PD) leads to restricted gait patterns, fall-related injuries, decreased... Postural impairment due to neuro-degenerative disorders such as Parkinson's Disease (PD) leads to restricted gait patterns, fall-related injuries, decreased...
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SubjectTerms	Active control Ankle Basal ganglia Center of pressure Central nervous system diseases Computer simulation Control stability Control theory Disease Progression Energy efficiency Feedback control Gait Human quiet stance Humans Intermittent control Movement disorders Neurodegenerative diseases Noise Parkinson Disease Parkinson's disease Pilot Projects Postural Balance Posture Strategy
Title	Explaining Parkinsonian postural sway variabilities using intermittent control theory
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