Abstract
BackgroundArrhythmokinesis, the variability in repetitive movements, is a fundamental feature of Parkinson’s disease (PD). We hypothesized that unimanual repetitive alternating finger tapping (AFT) would reveal more arrhythmokinesis compared to bimanual single finger alternating hand tapping (SFT), in PD.MethodsThe variability of inter-strike interval (CVISI) and of amplitude (CVAMP) during AFT and SFT were measured on an engineered, MRI-compatible keyboard in sixteen PD subjects off medication and in twenty-four age-matched controls.ResultsThe CVISI and CVAMP of the more affected (MA) and less affected (LA) sides in PD subjects were greater during AFT than SFT (P < 0.05). However, there was no difference between AFT and SFT for controls. Both CVISI and CVAMP were greater in the MA and LA hands of PD subjects versus controls during AFT (P < 0.01). The CVISI and CVAMP of the MA, but not the LA hand, were greater in PDs versus controls during SFT (P < 0.05). Also, AFT, but not SFT, detected a difference between the MA and LA hands of PDs (P < 0.01).ConclusionsUnimanual, repetitive alternating finger tapping brings out more arrhythmokinesis compared to bimanual, single finger tapping in PDs but not in controls. Arrhythmokinesis during unimanual, alternating finger tapping captured a significant difference between both the MA and LA hands of PD subjects and controls, whereas that during a bimanual, single finger tapping task only distinguished between the MA hand and controls. Arrhythmokinesis underlies freezing of gait and may also underlie the freezing behavior documented in fine motor control if studied using a unimanual alternating finger tapping task.
Highlights
Arrhythmokinesis, the variability in repetitive movements, is a fundamental feature of Parkinson’s disease (PD)
Unimanual, repetitive alternating finger tapping brings out more arrhythmokinesis compared to bimanual, single finger tapping in PDs but not in controls
Arrhythmokinesis during unimanual, alternating finger tapping captured a significant difference between both the more affected (MA) and less affected (LA) hands of PD subjects and controls, whereas that during a bimanual, single finger tapping task only distinguished between the MA hand and controls
Summary
Arrhythmokinesis, the variability in repetitive movements, is a fundamental feature of Parkinson’s disease (PD). Arrhythmokinesis has subsequently been revealed in many studies of repetitive movement in Parkinson’s disease (PD) and has been shown to be a useful marker of overall disease severity and of the effectiveness of medication and deep brain stimulation [2,3,4,5,6,7,8,9,10]. In studies using single finger flexion-extension movements, alternating between hands, the number of freezing episodes correlated with self-reported (FOG) severity but arrhythmokinesis was not observed during the task [14,15,16,17]. The authors concluded that arrhythmokinesis of upper extremity movements may not be a useful marker of freezing behavior as had been reported for FOG. Using a unimanual alternating finger tapping task we have reported both freezing episodes and arrhythmokinesis
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
