Brain correlates of right-handedness
Brain correlates of right-handedness
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DOI：
10.55782/ane-2007-1631
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发表时间：
2007-01-01
影响因子：
1.4
通讯作者：
Grabowska, Anna
中科院分区：
文献类型：
--
作者：
Gut, Malgorzata;Urbanik, Andrzej;Grabowska, Anna
神经影像技术的最新发展为研究惯用手与大脑功能结构之间的关系开辟了新的可能性。在这里，我们使用块设计报告了 12 名惯用右手的受试者的优势手和非优势手运动表征的功能磁共振成像测量。我们测量了用右手或左手进行简单和复杂的手指运动期间两个半球激活的神经组织总体积可能存在的不对称性。简单的动作包括食指的收缩/伸展，复杂的动作包括从小指到食指连续的手指-拇指相对。发现左半球激活相对于右半球激活普遍占主导地位。运动活动复杂性的增加导致持续激活区域的体积扩大以及同侧区域的更多参与，特别是在左半球。惯用手的运动引起较大的对侧激活（大于非惯用手的运动）和相对较小的同侧激活。由于同侧激活相对较大，非惯用手的运动导致两个半球的激活模式更加平衡。这表明惯用手（右手）主要由对侧（左）半球控制，而非惯用手则由左右半球控制。这种效果在执行复杂动作时尤其明显。惯用手对侧半球中参与运动控制的大脑区域的扩展可能为首选手的更高效率和更强大的运动技能提供神经基础。
Recent development of neuroimaging techniques has opened new possibilities for the study of the relation between handedness and the brain functional architecture. Here we report fMRI measurements of dominant and non-dominant hand movement representation in 12 right-handed subjects using block design. We measured possible asymmetry in the total volume of activated neural tissue in the two hemispheres during simple and complex finger movements performed either with the right hand or with the left hand. Simple movements consisted in contraction/extension of the index finger and complex movements in successive finger-thumb opposition from little finger to index finger. A general predominance of left-hemisphere activation relative to right hemisphere activation was found. Increasing the complexity of the motor activity resulted in an enlargement of the volume of consistently activated areas and greater involvement of ipsilateral areas, especially in the left hemisphere. Movements of the dominant hand elicited large contralateral activation (larger than movements of the non-dominant hand) and relatively smaller ipsilateral activation. Movements of the non-dominant hand resulted in a more balanced pattern of activation in the two hemispheres, due to relatively greater ipsilateral activation. This suggests that the dominant (right) hand is controlled mainly by the contralateral (left) hemisphere, whereas the non-dominant hand is controlled by both left and right hemispheres. This effect is especially apparent during execution of complex movements. The expansion of brain areas involved in motor control in the hemisphere contralateral to the dominant hand may provide neural substrate for higher efficiency and a greater motor skill repertoire of the preferred hand.