Upper extremity freezing and Dyscoordination in Parkinson's disease: Effects of amplitude and cadence manipulations

April J. Williams, Daniel S. Peterson, Michele Ionno, Kristen A. Pickett, Gammon M. Earhart

Research output: Contribution to journalArticlepeer-review

19 Scopus citations


Purpose. Motor freezing, the inability to produce effective movement, is associated with decreasing amplitude, hastening of movement, and poor coordination. We investigated how manipulations of movement amplitude and cadence affect upper extremity (UE) coordination as measured by the phase coordination index (PCI) - only previously measured in gait - and freezing of the upper extremity (FO-UE) in people with Parkinson's disease (PD) who experience freezing of gait (PD + FOG), do not experience FOG (PD-FOG), and healthy controls. Methods. Twenty-seven participants with PD and 18 healthy older adults made alternating bimanual movements between targets under four conditions: Baseline; Fast; Small; SmallFast. Kinematic data were recorded and analyzed for PCI and FO-UE events. PCI and FO-UE were compared across groups and conditions. Correlations between UE PCI, gait PCI, FO-UE, and Freezing of Gait Questionnaire (FOG-Q) were determined. Results. PD + FOG had poorer coordination than healthy old during SmallFast. UE coordination correlated with number of FO-UE episodes in two conditions and FOG-Q score in one. No differences existed between PD-/+FOG in coordination or number of FO-UE episodes. Conclusions. Dyscoordination and FO-UE can be elicited by manipulating cadence and amplitude of an alternating bimanual task. It remains unclear whether FO-UE and FOG share common mechanisms.

Original languageEnglish (US)
Article number595378
JournalParkinson's Disease
StatePublished - 2013
Externally publishedYes

ASJC Scopus subject areas

  • Neuroscience (miscellaneous)
  • Clinical Neurology
  • Psychiatry and Mental health


Dive into the research topics of 'Upper extremity freezing and Dyscoordination in Parkinson's disease: Effects of amplitude and cadence manipulations'. Together they form a unique fingerprint.

Cite this