We conducted a symptomatological study in six patients with micrographia to assess the effects of cues (stimul) for the purpose of obtaining hints for training methods. Five of the patients had cerebrovascular disorders and the remaining patient had parkinsonism.
   Micrographia was observed during open-eye/closed-eye spontaneous writing/transcription irrespective of the direction of writing. No acceleration in writing speed was seen. Assessment of the cues revealed that visual cues were more effective than auditory cues. Based on the fact that all six patients had no impairment of skilled motor behavior of the hands and fingers, micrographia is thought to he associated with the mechanism of coordination of writing behavior, not motor disorder.
   Three of the patients had specific symptoms : 1) dexter micrographia in a patient having a lesion in the right hemisphere, 2) bilateral micrographia in a patient having a lesion in the left hemisphere, and 3) micrographia specifically seen in the letters of a patient who showed a marked difference in writing of letters and drawing of successive figures. These findings indicate that the coordination mechanism of writing behavior works independently from motor control of figure drawing and other movements, exists in the right hemisphere, and exerts an influence on the right hand. They also suggest the possibility that patterns of writing behavior can be formed in both hands.

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We report a case who frequently misplaced digits in reading or writing tasks involving numerals, and discuss his numeral processing. The case was a 58-year-old, left-handed male who suffered from right hemiplegia, mild Broca aphasia and visual-spatial perception disabilities after a left putaminal hemorrhage. Numerals have two codes : one the Arabic code using Arabic numerals, and the other a verbal code which corresponds to reading out aloud. Most numeral processing tasks entail transcoding between the two codes. The patient's basic knowledge of numerals was intact, but he commonly erred in transcoding tasks : for example, he read aloud “ three hundred forty ” for “ 34 ”, and wrote “ 2105 ” when hearing “ two hundred fifteen ”. However, there was rarely any paralexia or paragraphia for digits, which confirms the dissociation of his two processing systems. In recent research on cognitive mechanisms of numeral processing, a distinction between lexical and syntactic processing has been proposed. On the basis of that, the patient's performance suggests that his syntactic processing of numerals is impaired. We think that, in both directions, transcoding between the two codes requires orientation to the spatial representation of the decimal system, and in this case we suggest the possibility that his deficits in operations involving internal spatial representation affect his syntactic processing.

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We report a Japanese patient of non-fluent childhood aphasia who showed difficulty in reading postpositions in a phrase or a sentence. Japanese postpositions are always written in kana characters (syllabary). The patient could name the kana characters when they were presented in isolation. Naming tasks of kana words, as well as of phrases and sentences written in a kanji (morphographs) and kana mixture were administered. He revealed signs of mild deep dyslexia or phonological dyslexia, such as pseudo-homophone, lexicality and word frequency effects in naming kana words, and also parts of speech and imageability effects in naming phrases and sentences written in kanji and kana. When naming ungrammatical phrases with incorrect postpositions, he tended to name them grammatically. These phenomena were thought to result from damage to phonological representation. He repeatedly substituted a postposition into others as if he were searching for the right answer. The number of each incorrectly produced postposition significantly correlated with its frequency, suggesting that phonological representation of a postposition with higher frequency is more efficiently activated than that with lower frequency.

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