发展性阅读障碍的脑机制——来自脑成像研究的证据

发展性阅读障碍是一种特殊的学习障碍，发展性阅读障碍的脑机制一直是研究者们关心的一个重要问题．随着脑成像技术的应用，人们在发展性阅读障碍的脑机制研究方面取得了重大进展．脑结构研究发现，发展性阅读障碍者在颞-顶叶、颞-枕叶、额下回、小脑等区域都存在一定的脑结构异常，这些脑结构异常要么表现在某个脑区的结构上，要么表现某个脑区结构的左右不对称性上．脑功能研究发现，发展性阅读障碍者出现脑结构异常的区域也大多表现出脑功能的异常．脑功能连接的研究发现，发展性阅读障碍者脑功能连接的异常不仅涉及到同侧脑区前后部分的连接，还涉及双侧脑区相应部分的连接．另外，中文发展性阅读障碍的研究发现了与拼音文字发展性阅读障碍不同的脑机制．这些研究成果为进一步揭示发展性阅读障碍的脑机制以及拓展中文发展性阅读障碍的研究提供了借鉴．

The Brain Mechanism of Developmental Dyslexia:Evidences From The Brain Image

Developmental dyslexia is a specific learning disability. The cerebral mechanism of development dyslexia is an important topic that has fascinated many researchers. With the introduction of brain imaging in studies of cerebral mechanism of development dyslexia, many achievements have been made. Studies of developmental dyslexia structure image found that development dyslexia showed brain structure abnormal in the parietotemporal region, occipitotemporal cortex, inferior frontal gyrus, and cerebellum et al, manifesting either in one specific area or by the asymmetry of one area; the functional image studies revealed that development dyslexia showed activity abnormal in most regions that proved to display structure abnormality; studies of brain functional connectivity demonstrates that the abnormality of development dyslexia happened not only in the connection between front-back part in one cerebral hemisphere, but also in the connection between the two hemispheres. In addition, some studies indicate Chinese development dyslexia has different brain mechanisms compared to that of alphabetic languages. These findings provide valuable insight for future developmental cerebral mechanisms research and for the expansion of Chinese development dyslexia research.