Whole brain functional connectivity in the early blind
Whole brain functional connectivity in the early blind
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失明早期的全脑功能连接
DOI：
10.1093/brain/awm121
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发表时间：
2007-08-01
期刊：
影响因子：
14.5
通讯作者：
Jiang, Tianzi
中科院分区：
文献类型：
--
作者：
Liu, Yong;Yu, Chunshui;Jiang, Tianzi
早期视觉剥夺会导致大脑发生变化，这可以用两种假说中的任何一种来解释。一般损失假说被提出来解释适应不良的情况，而代偿性可塑性假说则可以解释在使用剩余感官方面的一种优越能力。以前大多数基于任务的功能性磁共振成像（fMRI）研究都支持代偿性可塑性假说，但由于盲人无法执行视觉任务，所以很难提供证据来支持一般损失假说。对静息态fMRI数据的研究可能提供一个机会来同时检测盲人变化的两个方面。在这项研究中，我们从全脑的角度，利用静息态fMRI数据研究了早期盲人功能连接性的降低和增强。通过比较16名早期盲人（9名男性；年龄范围：15.6 - 29.3岁，平均年龄：22.1岁）每对大脑区域的相关系数与性别和年龄匹配的视力正常志愿者的相应系数，来确定改变的功能连接性。与视力正常的受试者相比，盲人在枕叶视觉皮层内部以及枕叶视觉皮层与顶叶躯体感觉皮层、额叶运动皮层和颞叶多感觉皮层之间表现出功能连接性降低。这种差异可能支持一般损失假说。然而，我们还发现，在生命早期开始学习盲文且每天练习时间更长，会使这些大脑区域之间产生更强的功能连接性。这些发现可能支持代偿性可塑性假说。此外，我们发现那些早期失明的人在枕叶皮层和额叶语言皮层之间有几种功能连接性增强，这表明代偿性可塑性占优势。我们的研究结果表明，当一种感觉模式被剥夺时，静息态功能连接性的变化可能是一般损失和代偿性可塑性的综合反映。
Early visual deprivation can lead to changes in the brain, which may be explained by either of two hypotheses. The general loss hypothesis has been proposed to explain maladjustments, while the compensatory plasticity hypothesis may explain a superior ability in the use of the remaining senses. Most previous task-based functional MRI (fMRI) studies have supported the compensatory plasticity hypothesis, but it has been difficult to provide evidence to support the general loss hypothesis, since the blind cannot execute visual tasks. The study of resting state fMRl data may provide an opportunity to simultaneously detect the two aspects of changes in the blind. In this study, using a whole brain perspective, we investigated the decreased and increased functional connectivities in the early blind using resting state fMRl data. The altered functional connectivities were identified by comparing the correlation coefficients of each pair of brain regions of 16 early blind subjects (9 males; age range: 15.6-29.3 years, mean age: 22.1 years) with the corresponding coefficients of gender- and age-matched sighted volunteers. Compared with the sighted subjects, the blind demonstrated the decreased functional connectivities within the occipital visual cortices as well as between the occipital visual cortices and the parietal somatosensory, frontal motor and temporal multisensory cortices. Such differences may support the general loss hypothesis. However, we also found that the introduction of Braille earlier in life and for longer daily practice times produced stronger functional connectivities between these brain areas. These findings may support the compensatory plasticity hypothesis. Additionally, we found several increased functional connectivities between the occipital cortices and frontal language cortices in those with early onset of blindness, which indicate the predominance of compensatory plasticity. Our findings indicate that changes in the functional connectivities in the resting state may be an integrated reflection of general loss and compensatory plasticity when a single sensory modality is deprived.