Subcortical locus of temporal coupling in the bimanual movements of a callosotomy patient
Journal/Book: Hum Movement Sci. 1999; 18: PO Box 211, 1000 AE Amsterdam, Netherlands. Elsevier Science Bv. 345-375.
Abstract: The timing of repetitive movements was assessed in a callosotomy patient under unimanual and bimanual conditions. Similar to neurologically healthy individuals, the patient exhibited strong temporal coupling in the bimanual condition. Moreover, for both the left and right hands, within-hand temporal variability was reduced in the bimanual condition compared to the unimanual conditions. This bimanual advantage is hypothesized to reflect the temporal integration of separable timing signals, one associated with the left hand and one associated with the right hand (Helmuth, L. L., & Ivry, R. B. (1996). When two hands are better than one: Reduced timing variability during bimanual movements. Journal of Experimental Psychology. Human Perception and Performance, 2, 278-293). The fact that it persists following callosotomy is inconsistent with models that attribute bimanual coordination in these patients to the control of a single hemisphere. Rather, the results suggest that motor commands from the two hemispheres are integrated subcortically.
Note: Article Ivry RB, Univ Calif Berkeley, Dept Psychol, 3210 Tolman Hall, Berkeley,CA 94720 USA
Keyword(s): temporal coupling; callosotomy; timing; motor control; bimanual; RHYTHMIC MOVEMENTS; SYNERGETIC THEORY; LEARNED PATTERNS; COORDINATION; INFORMATION; DYNAMICS; DISSOCIATION; FLUCTUATIONS; SYSTEMS; CORTEX