Abstract
I described four important elementary language symptoms and their lesions localizations. (1) anarthia(or apraxia of speech): the middle~lower part of the left precentral gyrus and underlying white matter. (2) phonemic parapahsia(without anarthria): the region from the posterior part of the left superior temporal gyrus, via supra-marginal guyrus, to the postcentral gyrus and underlying white matter. (3) word comprehension : the left middle frontal gyrus and the posterior part of the left superior and middle temporal gyrus and related white matter. (4) word finding : the left inferior frontal gyrus, the left angular gyrus, and the posterior part of the inferior temporal gyrus, and all related white matter. Regarding (3) and (4), clinical evaluation revealed the difference between the symptoms by the frontal lobe lesions and the posterior lesions. I suppose that temporal lobe is related to the ability of word generation due to semantic cues. The clinical findings accord with the findings obtained by functional images if the tasks are made from a viewpoint of which strategy the brain takes to perform the tasks.
