Kyoko Suzuki
Department of Disability Medicine,
Tohoku University Graduate School of Medicine, Sendai, Japan

Abstract; More than 100 years ago, observation of language impairment in aphasic patients was an only way to know the language function of a specific cerebral region. Now many clinical, radiological and neurophysiological techniques are available to research the neuronal bases of language. These techniques are divided into two groups. The first group includes lesion studies in aphasics, transcranial magnetic stimulation and cortical electric stimulation, which indicate language organization by suppressing neuronal activity on local areas and assessing the patient’s ability to perform language tasks. The second group includes functional MRI, PET, electroencephalography, magnetoencephalography, and functional transcranial doppler sonography, which detect, directly or indirectly, neuronal activity associated with performance of language tasks. Areas indicated by each of these methods relating to a specific process of language were not always in agreement. Sometimes partial overlapping of related areas was observed between two methods, and complete disagreement could also occur. This talk provides data using various methods and examples of partial disagreement among techniques. To clarify the neuronal bases of language, it is necessary to comprehend both advantages and disadvantages in each method and to perform not only quantitative but also qualitative analysis of the results.