TY - JOUR
T1 - Hand dominance and multi-finger synergies
AU - Zhang, Wei
AU - Sainburg, Robert L.
AU - Zatsiorsky, Vladimir M.
AU - Latash, Mark
N1 - Funding Information:
The study was in part supported by NIH grants NS-35032, AG-018751, and AR-048563.
PY - 2006/12/6
Y1 - 2006/12/6
N2 - Recent studies of arm movement reaching to a target have provided support for the Dynamic Dominance model of handedness, which proposes that each hemisphere/limb system is specialized for controlling different features of performance: The dominant system for control of the trajectory, and the nondominant system for control of the steady state final position. We now examine a more general form of this hypothesis by investigating differences between the right and left hands of right-handed persons in their ability to stabilize the combined action of a set of fingers. The subjects produced very quick pulses and steps of force from a low background force level while pressing with four fingers of one hand. An index of force stabilizing synergy showed a strong multi-finger synergy during steady-state force production followed by a small anticipatory drop in the index prior to the force increase. Hand differences emerged during the force increase: The left (non-dominant) hand showed a significantly larger drop in the synergy index. While our findings support the idea that the dominant system is specialized for stabilizing quick changes in performance variables, we failed to support a nondominant specialization for stabilizing steady-state isometric force. This may be a ceiling effect due to the simplicity of the task for either hand, or it might indicate that this aspect of the dynamic dominance hypothesis does not generalize to isometric conditions.
AB - Recent studies of arm movement reaching to a target have provided support for the Dynamic Dominance model of handedness, which proposes that each hemisphere/limb system is specialized for controlling different features of performance: The dominant system for control of the trajectory, and the nondominant system for control of the steady state final position. We now examine a more general form of this hypothesis by investigating differences between the right and left hands of right-handed persons in their ability to stabilize the combined action of a set of fingers. The subjects produced very quick pulses and steps of force from a low background force level while pressing with four fingers of one hand. An index of force stabilizing synergy showed a strong multi-finger synergy during steady-state force production followed by a small anticipatory drop in the index prior to the force increase. Hand differences emerged during the force increase: The left (non-dominant) hand showed a significantly larger drop in the synergy index. While our findings support the idea that the dominant system is specialized for stabilizing quick changes in performance variables, we failed to support a nondominant specialization for stabilizing steady-state isometric force. This may be a ceiling effect due to the simplicity of the task for either hand, or it might indicate that this aspect of the dynamic dominance hypothesis does not generalize to isometric conditions.
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U2 - 10.1016/j.neulet.2006.09.048
DO - 10.1016/j.neulet.2006.09.048
M3 - Article
C2 - 17018249
AN - SCOPUS:33750429616
SN - 0304-3940
VL - 409
SP - 200
EP - 204
JO - Neuroscience letters
JF - Neuroscience letters
IS - 3
ER -