Coupling dynamics in interlimb coordination.
In 1:1 frequency locking, the interlimb phase difference phi is an order parameter quantifying the spatial-temporal organization of 2 rhythmic subsystems. Dynamical modeling and experimental analyses indicate that an intentional parameter phi psi (intended coordination mode, phi = 0 degrees or phi = 180 degrees) and 2 control parameters omega c (coupled frequency) and delta omega (difference between uncoupled eigen-frequencies) affect phi. An experiment was conducted on 1:1 frequency locking in which phi psi, omega c, and delta omega were manipulated using a paradigm in which a person swings hand-held pendulums. As delta omega deviated from 0, the observed phi deviated from the phi psi, indicating a displacement in the phi attractor point. The displacements were exaggerated by increasing omega c. The displacements were coordinated with a decrease in the stability of phi and with higher harmonics in power spectrum of phi. Implications of the results for modeling interlimb coordination are discussed.
Schmidt
R C
RC
Department of Psychology, Tulane University, New Orleans, Louisiana 70118.
Shaw
B K
BK
Turvey
M T
MT
D000328:Adult; D001288:Attention; D005260:Female; D007839:Functional Laterality; D006112:Gravitation; D006801:Humans; D007699:Kinesthesis; D008297:Male; D009039:Motion Perception; D009043:Motor Activity; D004856:Postural Balance; D011601:Psychophysics; D011930:Reaction Time