We study the effects of Parkinson's disease (PD) on the long-term fluctuation and phase synchronization properties of gait timing (series of interstride intervals) as well as gait force profiles (series characterizing the morphological changes between the steps). We find that the fluctuations in the gait timing are significantly larger for PD patients and early PD patients, who were not treated yet with medication, compared to age-matched healthy controls. Simultaneously, the long-term correlations and the phase synchronization of right and left leg are significantly reduced in both types of PD patients. Surprisingly, long-term correlations of the gait force profiles are relatively weak for treated PD patients and healthy controls, while they are significantly larger for early PD patients. The results support the idea that timing and morphology of recordings obtained from a complex system can contain complementary information.
|Number of pages||11|
|Journal||Physica A: Statistical Mechanics and its Applications|
|State||Published - 15 Sep 2007|
Bibliographical noteFunding Information:
We thank Shay Moshel, Avi Gozolchiani and Leor Gruendlinger for helpful discussions as well as the subjects for their participation, time and effort. This work was supported in part by the Minerva Foundation, by NIH Grants AG-14100, RR-13622, HD-39838 and AG-08812, by the US-Israel Binational Science Foundation, by the Parkinson's Disease Foundation (PDF), New York, by the National Parkinson Foundation (NPF), Miami USA, by the EU project DAPHNet (Grant 018474-2), and by the Deutsche Forschungsgemeinschaft (Grant KA 1676/3).
- Detrended fluctuation analysis
- Parkinson's disease
- Phase synchronization