Abstract
This article presented the neural basis on sentence production and comprehension from the viewpoint of what is the sine qua non for sentence production and comprehension. I investigated 23 right handed aphasic patients with focal brain damage administrating various tasks of sentence production and comprehension, and analyzed the error patterns. The results suggested that frontal regions subserve aspects of decision and alteration of the view point before the sentence production and in the process of sentence comprehension. The parietal might support vigilance during the sentence processing.
