Practice effects on local and global dynamics of the ski-simulator task

• Published in: Experimental brain research 2006-03, Vol.169 (3), p.350-360
• Main Authors: HONG, S. L, NEWELL, K. M
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Analysis of Variance; Audition; Biological and medical sciences; Biomechanical Phenomena; Computer Simulation; Female; Fundamental and applied biological sciences. Psychology; Humans; Knee Joint - physiology; Male; Motor control and motor pathways. Reflexes. Control centers of vegetative functions. Vestibular system and equilibration; Motor Skills - physiology; Nonlinear Dynamics; Perception; Postural Balance - physiology; Practice (Psychology); Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Skiing - education; Skiing - physiology; Spectrum Analysis; Vertebrates: nervous system and sense organs
• ISSN: 0014-4819; 1432-1106
• DOI: 10.1007/s00221-005-0145-4

This experiment examined the acquisition of the global and local dynamics of the changes in the total body center of mass-platform and inter-limb coordination motions over the course of practice (20, 30 s trials each day for 7 days) in the ski-simulator task. Four blocks of trials, representative of early, moderate, and extensive practice were analyzed through power spectrum and coherence analyses. The oscillation frequencies of the knee joints became tuned to that of the platform-performer system and there were changes due to practice in the lower inter-limb coordination dynamics independent of the center of mass and platform coordination pattern. Acquisition of global level dynamics occurs to achieve a stable task solution that can allow for degenerate frequency- and phase-locking of the mechanical degrees of freedom at both the local intra- and inter-limb levels.