[The progress of non-invasive examination of the brain function and child neurology]

During the last 2 decades of the 20th century, various non-invasive examinations of the brain function developed strikingly with the advance of electronics. The examination procedures were tentatively classified into the following generations: the 1st generation: EEG, the 2nd: evoked potentials using signal averaging system, the 3rd: CT and MRI using reconstruction of imaging, 4th: PET, SPECT, fMRI, MEG, MRS and DTI which are categorized in functional imaging, 5th: optic topography combining the functional imaging and time factor. In this article, the outlines of the principle and application of the 4th and 5th generation methods are described. Their application to children requires the development of less invasive and simpler methods. These examination tools still stand on the start line, and will be widely applied to the neurology field in future. Child neurologists should be concerned with the development of their application.