Differences in Cross Modulation of Physiological Tremor in Pianists and Nonmusicians


Medicine & Science in Sports & Exercise: September 2011 - Volume 43 - Issue 9 - pp 1707-1715
doi: 10.1249/MSS.0b013e318213f262
Applied Sciences

Purpose: The study was undertaken to investigate the contralateral overflow effect on physiological tremors in pianists and nonmusicians. Group differences in cross modulation on underlying finger fractionated movement were characterized.

Methods: Physiological tremors of the right index, middle, ring, and little fingers were recorded in 12 right-handed pianists and 12 matched nonmusician controls; meanwhile, two contralateral resistance protocols (unilateral handgrip using the left hand at slight and maximal efforts) were randomly conducted.

Results: Digit tremors of the control and pianist groups were differentially modulated with the resistance protocols. An increase in gripping force led to cross excitations over 8-12 Hz digit tremors and interdigit tremor coupling for the nonmusicians. An opposite cross effect was noted for the pianists, who exhibited significant tremor suppression and the release of interdigit tremor coupling. Further analysis of tremor dynamics revealed that contralateral gripping reduced the complexity of digit tremors of the pianists but added to the tremor complexity of the nonmusicians.

Conclusions: Cross modulation on digit tremors suggests that pianists could centrally suppress unintended motor excitation across the midline. When the opposite hand is active, pianists have superior finger independence that allows them to achieve artistic aspects of musical performance.

1School of Physical Therapy, Chung Shan Medical University, Taichung, TAIWAN; 2Physical Therapy Room, Chung Shan Medical University Hospital, Taichung, TAIWAN; 3Institute of Allied Health Sciences, College of Medicine, National Cheng Kung University, Tainan, TAIWAN; and 4Department of Physical Therapy, College of Medicine, National Cheng Kung University, Tainan, TAIWAN

Address for correspondence: Ing-Shiou Hwang, Ph.D., Institute of Allied Health Sciences, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan; E-mail: ishwang@mail.ncku.edu.tw.

Submitted for publication October 2010.

Accepted for publication January 2011.

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©2011The American College of Sports Medicine