A study of language disorders associated with dementia of Alzheimer type in Japanese: A preliminary study

We reported here the quantitative analyses of the language disturbances in mild to moderate dementia of Alzheimer type (DAT) using the Japanese versio n of Western Aphasia Battery (WAB) and compared these data with those of no rmal control subjects. Aphasic symptoms were found in 19 out of 20 DAT pati ents. Sixteen cases were classified into amnesic aphasia and three cases in Wernicke aphasia by WAB criteria. In reading tests, significant difference s were found in understanding sentences, Kanji recognition by hearing its s tructure, and expressing Kanji structure. In writing tests, significant dif ferences were found in the ability to write in dictation and the ability to express ideas by writing. However, the ability to write Kana (Japanese pho nogram) was relatively preserved. These results suggest that Japanese DAT p atients demonstrate difficulties in writing Kanji letters rather than Kana letters at least in the beginning of the disease.