| Language is a specific higher brain function in human being, It is important to elucidate the brain mechanism about language, which can help us reveal the arcanum in human brain and the pathogeny in congenital or acquired disordiers of languge. Studying the lingual and cognitive is studying the mechanism of processing and integrating lingual information in human, including inputing, storing, internal processing and outputing. Scholars have carried out several studies about the brain mechanism of processing shape, sound and meaning of words. Initially, they acquired many experimental data with cognitive psychological methods, such as reaction time recording, etc. They also collected hospital cases of aphasia and dyslexical patient to find disciplinarian. However, due to limitations of above mesurement, it is difficult to directly study the lingual function of human brain, so some of key problems about the final conclusions are still unable to be solved. Untill recently, arousing brain functional imaging techniques provide scientists with mor obvious measurements which can be used to directly observe and analysis activities in brain. Brain fuctional imaging techniques include fMRI, PET, ERPs, MEG, etc. Michael Posner firstly studied volunteer of brain activity in process of 'seeing words', 'listening words', 'reading words' and 'producing words' after visual and audio presentation. His articles were published on Science. Since then, brain function imaging techniques were widely used to study the higher functions of human brain. MEG is abbreviation for magnetoencephy. It is a kind of brain function imaging techniques, which can measure brain functions noninvasively. It has specially high sensitiveness, which made it accurately capture the quite faint signals from deep end of brain; It has specially high time-resolving power (less than 1ms), which made it accurately measure sequence of physiological activities in brain, further identifying the primary lesions or secondary lesions; It has specially highspace-resolving power, which made it superpose the signal of brain function over CT or MRI images, the precision of superposition is up to 2mm. Compared with fMRI and PET, space-resolving power of MEG is similar to that of fMRI and PET, however, time-resolving power of MEG is much more than the latter. Superposing high time- and space- resolving dipole over the CT or MRI images, which is also called magnetic source imaging (MSI), can compose real-time functional images like movie, also can observe and trace the origin and transmit of brain activities. The complement and combination between anatomy and function provide 3D maps of neural function orientation to clinic and research. Up to now, MSI is a only diagnostic method which not only may orientate and monitor the rapidly changing brain functional activities, but also need not administration of radioactive reagents or other invasive measurement. This study is to investigate brain activities in process of the cognitive tasks about visual language, picture naming, number contrast, calculation and auditory language, to explore the higher function related to language and cognize, to establish the basis further to study the pathogeny and clinic about congenital dyslexic and acquired aphasia.1. MSI study of visual language.The purpose of this experiment is to investigate the dynamic functional composition in the brain cognitive process of visual language. 10 volunteers cooperate the cognitive tasks of the written words and symbols, at the same time, they were measured with 306 channel whole-head biomagnetometer in magnetic-shield room. Magnetic signals from all stimulations were accumulated respectively in groups of true words, false words and symbols, and were modeled as equivalent current dipoles (ECDs) by using the nonlinear Levenberg-Marquardt algorithm on a BEM head model to elucidate brain focal activities. Then the participators were taken MRI examinations, then acquired data were reconstructed as 3-dimension brain images. Finally, the brain functio...
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