The aim of this study was to investigate episodic memory in tasks using the five sensory modalities, i. e., visual, auditory, olfactory, gustatory and tactile, in dementia of the Alzheimer type (DAT).
    Eleven DAT patients and five normal controls (NC) were tested on immediate recognition and recognition after five minutes for the five sensory modalities. The test consisted of five memory tasks and ten recognition tasks for each sensory modality. The rates of correct responses on immediate recognition and recognition after five minutes for each sensory modality were lower in the DATs than those of the NCs. Especially significant differences were observed in the rates of correct responses in visual, auditory and tactile modalities for both types of recognition. The NCs did not show differences in rate of correct responses for any sense between immediate recognition and recognition after five minutes. Meanwhile, the rate of correct responses for immediate recognition in the DATs decreased significantly in the visual, auditory and tactile modalities compared to those for recognition after five minutes, while those of the gustatory and olfactory modalities were almost identical for both immediate recognition and recognition after five minutes.
    These results indicate that episodic memory of gustatory and olfactory modalities is relatively well preserved in DATs.

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    We report a case of adult-onset adrenoleukodystrophy. A 35-year-old right-handed man was admitted with impairments of auditory and visual acuity. Family history was negative for neurologic and psychiatric disorders. He had clear consciousness and good orientation. Neurologic examination showed left-dominant auditory disturbance which was proven by audiometry to be of the retrocochlear type. Although he had a partial visual field defect in the right eye, his visual acuity was 0.5 (right) and 0.4 (left) with normal color perception. Motor and cerebellar function were normal. Deep tendon reflexes were hyperactive together with positive Babinski signs. The sensory system was normal except for impaired skin writing tests and tactile extinction phenomenon on the left side. However, psychometric evaluation could be carried out without any trouble. Understanding of spoken and written language was normal on the Standard Language Test for Aphasia. However, some impairments in recognition of word accents and spatial direction of sound sources were observed. Regarding comprehension of non-verbal sounds, he was unable to identify familiar, meaningful nonverbal environmental sounds (e. g., ringing bell). These findings supported the diagnosis that he had auditory agnosia without aphasia.
    T2-weighted MRIs of the brain showed diffuse high signal intensities in the deep white matter of the occipito-temporo-parietal lobe. Laboratory tests disclosed high plasma concentration of very long chain fatty acid. Cerebrospinal fluid protein was elevated. In conclusion, the present case was thought to have auditory agnosia with a mechanism involving transcortical fibers due to adrenoleu-kodystrophy.

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    A 53-year-old right-handed man with a 55-month history of conduction aphasia and a left hemiparesis following a right putaminal hemorrhage was reported. CT scan revealed a hemorrhage area in the right putaminal and atrophy in the left sylvius sulcus. His pattern of language impairment was characterized by disturbance of repetition with preserved comprehension and word-findings. Repetition errors consisted of substitution of one postpositional word ( “joshi” ) for another. These repetition errors appeared similar to “paragrammatistic paraphasias” (as described by Hadano), but remained unchanged even after 55 months after onset.

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    The progress of ten neologistic jargonaphasic patients was analyzed and compared, based on clinical observation and changes in total SLTA (Standard Language Test for Aphasia) rating scores between two points in time. Some claims have been reported that semantic and phonological paraphasias increase with the reduction of neologisms, resulting in practical speech that includes much information. The ten jargonaphasics studied here showed an apparent difference in their process of improvement : one patient improved so remarkably that he could express complicated matters, while the other nine patients plateaued at the level where they could have a simple conversation. A change in total SLTA rating scores indicates a good recovery of comprehension in all the cases, better utterance in six and improvement of writing in only three. Finally, continuous neologisms or more content words were found in some cases, which suggests that the mechanism of jargon speech varies by patient.

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    We reported a case of fluent aphasia which exhibited certain characteristics of transcortical sensory aphasia (TSA) following a left frontal lobe lesion involving the Broca's area. The patient was a 59-year-old right-handed male. MRI and CT showed the lesion to occupy part of the left second frontal gyrus, the posterior part of the left third frontal gyrus, and the left insula cortex and underlying white matter. Spontaneous speech and repetition were good and articulation was normal. Comprehension of words was preserved but that of sentences was poor. In spite of good oral reading, his reading comprehension was slightly impaired. He showed typical characteristics of TSA. We concluded that this comprehension deficit was caused not only by semantic disturbance but also by syntactic disturbance.
    Recently there have been a number of reports in Japan of TSA following a frontal lobe lesion including the Broca's area. We propose that it would be better to divide such TSA cases into three independent groups. The three groups are characterized by (1) echolalia and/or paralalia, (2) severe comprehension deficit and (3) mild comprehension deficit, respectively. The third group features a number of common linguistic aspects : mild comprehension deficit, syntactic disorder, literal paraphasia of Kana writing, and early amelioration. The present case belongs to the third group.

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    This study investigated the effects of subjective frequencies of written forms on the word reading time of aphasic patients. Participants in the study included 10 nonfluent type and 10 fluent type aphasic patients. Sets of 15 kanji-type words (words written frequently in kanji but rarely in hiragana) and 15 hiragana-type words (words written frequently in hiragana but rarely in kanji), chosen based on a study by Ukita et al. (1991 a), were presented to the patients in both kanji and hiragana (total of 60 words), and they were required to read aloud each word as quickly as possible. Patients were found to read aloud kanji-type words faster when presented in kanji than when given in hiragana, and to read aloud hiragana-type words faster when presented in hiragana than when given in kanji. Also, when words were presented in hiragana, hiragana-type words were found to be read faster than kanji-type words. These results suggest that hiragana-type words presented in hiragana are read not letter-by-letter but as a whole unit, and that subjective frequencies of written forms are critical when considering the processing differences between script types in Japanese.

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