Related Experiment Videos
Fluctuations and phase symmetry in coordinated rhythmic movements
Journal of Experimental Psychology. Human Perception and Performance
|November 1, 1986
Summary
Human rhythmic movements, like swinging pendulums, show distinct timing patterns. Clocking fluctuations increase with out-of-phase movements, suggesting phase constraints impact movement stability.
Area of Science:
- Biomechanics
- Human Locomotion
- Movement Science
Background:
- Mammalian terrestrial locomotion is characterized by pendular, clocking movements.
- Rhythmic movements involve periodic timing and powering, governed by distinct principles.
- Investigating human locomotion can provide insights into fundamental movement control.
Purpose of the Study:
- To examine pendular, clocking behavior in human wrist movements.
- To differentiate between 'clock' and 'motor' contributions to movement timing.
- To assess the impact of in-phase versus out-of-phase coordination on movement stability.
Main Methods:
- Utilized a hand-held pendulum swinging task at the wrists.
- Applied Wing and Kristofferson's (1973) method to parse timing variance.
- Analyzed periodicity and fluctuations in 'clock' and 'motor' components under different phase conditions.
Main Results:
- Mean periodicity of wrist-pendulum movements remained consistent regardless of phase.
- 'Clock' fluctuations were significantly greater in out-of-phase movements compared to in-phase movements.
- 'Motor' fluctuations were independent of phase and reflected individual system deviations from preferred periods.
Conclusions:
- Movement phase relations act as constraints on the internal timing ('clock') mechanisms.
- In-phase coordination leads to more stable 'clock' states than out-of-phase coordination.
- The findings elucidate the distinct roles of timing and motor processes in rhythmic human locomotion.