Alazmani, A., Culmer, P., Levesley, M., Mon-Williams, M. and Bhakta, B. (2009) The coordination of upper and lower arm rotation. Experimental Brain Research, 192 (4). pp. 635-649. ISSN 0014-4819Full text not available from this repository.
We tested the hypothesis that the upper and lower arm act as a coordinative structure coupled through a higher order control system. Five healthy participants moved their hand between two targets in ten conditions via internal/external rotation of the shoulder. In eight conditions, the task required concurrent rotation of the lower arm (180° pronation/supination). Movements were stereotypical within a condition but plotting the upper and lower arm angle against each other produced an asymmetrical pattern. With internal rotation, the upper arm reached peak angular velocity slower than the lower arm but this was reversed with external rotation. In two conditions, participants were asked to move faster and slower than their normal speed. The peak speed, time to peak speed and duration were predictable for the different tasks. Internal and external asymmetries decreased with faster movements. In addition a decrease in upper arm amplitude (from 90° to 30°) removed the asymmetry. The asymmetry was unaffected by initial posture but was exaggerated when external rotation was paired with pronation rather than supination, and internal rotation combined with supination (versus pronation). However, the presence of the same fundamental pattern suggests that the asymmetry is not due to biomechanical factors but might arise because of the difficulties involved in visually monitoring the hand when it is close to the body. The results support the idea that functional coupling can occur between upper and lower arm rotations and thus provides further evidence for a higher order control system which is responsible for coordination of arm segment movement.
|Keywords:||arm movement; coordination; coordinative structure; lower arm rotation; Prehension|
|Institution:||The University of Leeds|
|Academic Units:||The University of Leeds > Faculty of Engineering (Leeds) > School of Mechanical Engineering (Leeds)
The University of Leeds > Faculty of Medicine and Health (Leeds) > Institute of Psychological Sciences (Leeds) > Cognitive Psychology (Leeds)
The University of Leeds > Faculty of Medicine and Health (Leeds) > Institute of Molecular Medicine (LIMM) (Leeds)
|Depositing User:||Repository Officer|
|Date Deposited:||18 Jun 2009 14:59|
|Last Modified:||29 Sep 2010 14:24|