Ali Falaki1, Hang Jin Jo2, Mechelle M Lewis3, Barbara O'Connell4, Sol De Jesus4, James McInerney4, Xuemei Huang5, Mark L Latash6. 1. Department of Kinesiology, The Pennsylvania State University, University Park, PA 16802, USA. 2. Department of Neurological Surgery, The Miami Project to Cure Paralysis, Miami, FL 33136, USA. 3. Departments of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA. 4. Departments of Neurosurgery, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA. 5. Departments of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA; Departments of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA; Departments of Radiology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA; Departments of Neurosurgery, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA. 6. Department of Kinesiology, The Pennsylvania State University, University Park, PA 16802, USA. Electronic address: mll11@psu.edu.
Abstract
OBJECTIVE: We explored effects of deep brain stimulation (DBS) in patients with Parkinson's disease (PD) on the synergic control of fingers in a multi-finger force production task and of muscles in a task involving vertical posture. METHODS: The finger task involved the four fingers of a hand producing accurate total force followed by a targeted quick force pulse. The postural task involved releasing a load from extended arms. The analysis of synergies was performed within the framework of the uncontrolled manifold hypothesis. RESULTS: DBS led to no significant changes in indices of stability during steady-state phases. In contrast, DBS improved indices of agility, quantified as anticipatory synergy adjustments that reduced stability of salient performance variables in preparation to their quick change. There were moderate-to-strong correlations between indices of both stability and agility measured in the multi-finger force production and multi-muscle whole-body action. CONCLUSIONS: Our results point at systemic changes in synergic control in PD. They show that DBS is effective in improving only one components of synergic control related to agility in performance being relatively ineffective for the stability component. SIGNIFICANCE: The results show systemic brain mechanisms of synergies and suggest differential effects of DBS on indices of stability and agility.
OBJECTIVE: We explored effects of deep brain stimulation (DBS) in patients with Parkinson's disease (PD) on the synergic control of fingers in a multi-finger force production task and of muscles in a task involving vertical posture. METHODS: The finger task involved the four fingers of a hand producing accurate total force followed by a targeted quick force pulse. The postural task involved releasing a load from extended arms. The analysis of synergies was performed within the framework of the uncontrolled manifold hypothesis. RESULTS: DBS led to no significant changes in indices of stability during steady-state phases. In contrast, DBS improved indices of agility, quantified as anticipatory synergy adjustments that reduced stability of salient performance variables in preparation to their quick change. There were moderate-to-strong correlations between indices of both stability and agility measured in the multi-finger force production and multi-muscle whole-body action. CONCLUSIONS: Our results point at systemic changes in synergic control in PD. They show that DBS is effective in improving only one components of synergic control related to agility in performance being relatively ineffective for the stability component. SIGNIFICANCE: The results show systemic brain mechanisms of synergies and suggest differential effects of DBS on indices of stability and agility.
Authors: Daniel Martinez-Ramirez; Wei Hu; Alberto R Bona; Michael S Okun; Aparna Wagle Shukla Journal: Transl Neurodegener Date: 2015-06-27 Impact factor: 8.014
Authors: Elke Heremans; Evelien Nackaerts; Griet Vervoort; Sarah Vercruysse; Sanne Broeder; Carolien Strouwen; Stephan P Swinnen; Alice Nieuwboer Journal: PLoS One Date: 2015-11-18 Impact factor: 3.240
Authors: Sandra M S F Freitas; Paulo B de Freitas; Mechelle M Lewis; Xuemei Huang; Mark L Latash Journal: Exp Brain Res Date: 2018-11-20 Impact factor: 1.972