Abstract
To investigate the distinguishable features of writing in normal aging and Alzheimer's disease (AD) , the MMSE items of spontaneous writing by 160 subjects in a community were analyzed. The subjects were randomly selected and were consisted of 97 normal older adults (Clinical Dementia Rating, CDR 0), 48 CDR 0.5 subjects (very mild AD), and 15 AD patients (CDR 1 & 2) .The numbers of Kanji and Kana which the subjects were able to write as well as the errors in writing were analyzed.
We found that the mean numbers of Kanji and Kana were decreased step by step from normal adults to AD patients. The CDR 0 group showed errors for Kana or Kanji, however, CDR 0.5 or 1+ showed both errors for Kana and Kanji. There was no difference between the CDR 0 and 0.5 groups for errors in the noun, however, the CDR 1+ group showed significantly greater errors. For the verb and adjective, the connection between Kanji and Kana (Okuri-Kana) was disturbed in the CDR 0.5 group.
To notice only on the formal error may not be sufficient for distinguish between normal aging and very mild AD, since about 30% of normal adults show such errors. However, the errors of verb and adjective (Okuri-Kana) may be affected by pathological process of very mild AD.
