Bilateral multifinger deficits in symmetric key-pressing tasks
Bilateral multifinger deficits in symmetric key-pressing tasks
复制标题
对称按键任务中的双侧多指缺陷
DOI：
10.1007/s002210100801
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发表时间：
2001
影响因子：
2
通讯作者：
M. Latash
中科院分区：
文献类型：
--
作者：
Zong;V. Zatsiorsky;Sheng Li;F. Danion;M. Latash
抽象的。同时双侧和多指用力时的最大随意力已被证明小于单侧或单指用力的总和。本研究的目的是研究与双侧多指任务相关的力缺陷。8名大学生被试分别完成了4种类型的最大等长按键任务：（1）单侧单指，（2）双侧单指，（3）单侧多指，（4）双侧多指。记录食指（I）、中指（M）、无名指（R）和小指（L）产生的力以及外源性手指屈肌的表面肌电图（EMG）。多指缺陷（MFD）定义为在单侧单指任务中，一组手指产生的力（或EMG）与单个手指产生的力（或EMG）之和之间的百分比差异。双侧缺陷（BLD）定义为一组手指产生的力（或EMG）与左右手手指子集产生的力（或EMG）之和之间的百分比差异。在所有的双侧多指任务和一些双侧单指任务中，都发现了显著的BLD和MFD。BLD和MFD都依赖于涉及的手指数量。BLD的范围为3%至22.7%的力量和8.9%至31.0%的肌电图，包括双边单指和双边多指任务。在双侧I-、IM-、IMR-和IMRL-手指任务中，有效MFD分别为13.2%、37.8%、53.2%和52.3%; EMG中相应的MFD分别为11.7%、51.3%、67.6%和71.0%。肌电图中的BLD和MFD与相应的力缺陷平行变化。有人认为，神经天花板效应仍然是最合理的机制所观察到的赤字。在涉及多个身体部位的任务期间，中枢神经系统无法同时最大限度地激活大量肌肉群。在双侧多指任务期间，天花板效应可以分层地组织：（1）双侧共享某个有限的神经驱动，导致BLD;（2）在每只手处，多个手指共享某个有限的神经驱动，导致手内的MFD;（3）双侧和单侧多指水平的缺陷在双侧多指任务中是累积的，导致与任务相关的更高的赤字。
Abstract. Maximal voluntary force during simultaneous bilateral and multifinger exertion has been shown to be smaller than the sum of unilateral or single-finger exertions. The goal of this study was to study the force deficit associated with bilateral multifinger tasks. Eight normal college students performed four types of maximal isometric key-pressing tasks: (1) unilateral single-finger, (2) bilateral single-finger, (3) unilateral multifinger, and (4) bilateral multifinger. Forces produced by the index (I), middle (M), ring (R), and little (L) fingers and surface electromyography (EMG) of extrinsic finger flexors were recorded. Multifinger deficit (MFD) was defined as the percentage difference between the force (or EMG) produced by a set of fingers and the sum of the forces (or EMGs) produced by the individual fingers in their unilateral single-finger tasks. Bilateral deficit (BLD) was defined as the percentage difference between the force (or EMG) produced by a set of fingers and the sum of the forces (or EMGs) produced by the finger subsets of the left and right hands. Significant BLD and MFD in force and EMG were found for all bilateral multifinger tasks and some of the bilateral single-finger tasks. Both BLD and MFD were dependent on the number of fingers involved. BLD ranged from 3% to 22.7% for force and from 8.9% to 31.0% for EMG, including bilateral single-finger and bilateral multifinger tasks. MFDs in force during bilateral I-, IM-, IMR-, and IMRL-finger tasks were 13.2%, 37.8%, 53.2%, 52.3%, respectively; and the corresponding MFDs in EMG were 11.7%, 51.3%, 67.6%, and 71.0%, respectively. BLD and MFD in EMG were found to vary in parallel with the corresponding force deficits. It was suggested that the neural ceiling effect remains the most plausible mechanism underlying the observed deficits. The central nervous system is unable to activate maximally a large number of muscle groups at the same time during tasks involving multiple body parts. During bilateral multifinger tasks, the ceiling effect may be organized hierarchically: (1) a certain limited neural drive is shared bilaterally, leading to a BLD; (2) at each hand, a certain limited neural drive is shared by multiple fingers, leading to MFD within a hand; (3) the deficits at bilateral and unilateral multifinger levels are cumulative during bilateral multifinger tasks, leading to a higher deficit associated with the tasks.
猴子前臂多腱外在手指肌肉的形态区域。
DOI：
10.1159/000147465
发表时间：
1993
期刊：
Acta anatomica
影响因子：
--
作者：
Serlin,DM;Schieber,MH
通讯作者：
Schieber,MH
影响因子：
56.9
作者：
SCHIEBER, MH;HIBBARD, LS
通讯作者：
HIBBARD, LS