To explore the neural mechanisms underlying recovery of language output, we investigated, using functional MRI, the pattern of brain activity during explicit word retrieval to initial letter cues in five aphasic patients and six normal control subjects. The aphasic patients presented with mild to moderate degree of language impairment with word list generation < 50% as evidenced by the Standard Language Test of Aphasia. One of the patients was examined twice in the course of recovery. The cerebral activation of normal control subjects during word retrieval to letter cues was most prominently observed in Broca's area with additional activation in the surrounding areas including the left anterior prefrontal and medial frontal cortices, the insula and the superior temporal lobe. The modification of language-related brain function of each aphasic patient was evaluated and compared with the activation pattern of normal controls. Overall activation in Broca's area of the aphasic patients appeared less significant than normal controls. Good word retrieval was related to the relative functional spare/restoration of Broca's and adjacent areas. Insufficient functional recovery of Broca's and ipsilateral adjacent area may lead to functional activation of the right-sided homologous regions, which presumably is related to partial language recovery. The findings suggest that the functional restoration of language appeared variable in individual patients. Future studies using longitudinal functional neuroimaging evaluation are warranted to further clarify across-subject variability in aphasia recovery.

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   The purpose of this study is to investigate the factors using objective methods relation to the improvement, recovery process and the mechanism of the disorder of 18 acquired childhood aphasia (ACA) with the localized lesions of the brain. We use the regularized scale of the Standard Language Test of Aphasia (SLTA) as an index. Eight ACA patients with localized lesions of the posterior part of the left brain were compared with adult aphasic patients with almost same lesions about the recovery level and process. As results, ACA patients with cerebro-vascular artery disease and trauma showed higher recovery level than those with infection. In three factors result from factor analysis, comprehension improved at first, then speech, and writing improved. Patients with ACA showed faster and higher recovery level than adult aphasics. Though the recovery level is high, the improvement was limited, and the scores of oral commands, sentence repetition, and Kanii writing were significantly lower than those of controls as well as the adult aphasic patients. The data from another cognitive neuropsychological tests suggest the possibility that the phonological and semantic disorder is likely to affect the limited improvement.

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   We found previously that patients with Parkinson's disease (PD) were impaired with respect to the recognition of fear and disgust in facial expressions. To investigate the neural mechanisms that underlie this impairment, we recorded visual event-related potentials (ERPs) in response to the viewing of fearful facial expressions in 8 healthy normal controls, 8 patients with Parkinson's disease and 3 patients with herpes simplex encephalitis (HSE). We used a SSB/DT (Scalp-Skull-Brain/Dipole Tracing) method to determine the location of components of the ERPs. The ERPs that were elicited in response to the facial stimuli consisted of a negative peak (N1), two positive peaks, and a subsequent slow negative shift. N1 was localized, predominantly, to the bilateral occipitotemporal region. For N1, the equivalent current dipoles were concentrated bilaterally in the fusiform gyrus, superior temporal gyrus, parahippocampal gyrus, amygdala, and cerebellum in normal subjects. By contrast, in patients with PD, N1 was centered bilaterally in the angular gyrus, supramarginal gyrus, and superior parietal lobule, and there was no neuronal activity in the amygdala. In patients with HSE, the dipoles of N1 were localized in the left inferior temporal gyrus and bilateral orbitofrontal gyrus. This result suggests that neither the amygdala nor the temporal visual-associated cortices in patients with PD are involved in responding to fearful expressions. Corticostriatal connections may be variably affected by a lack of dopamine or by pathological changes in the amygdala. Consequently, somatosensory recruitment may overcome the mild cognitive emotional deficits that are present in patients with PD.

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   We describe a patient presenting with diagonistic dyspraxia and pathologic grasping reflex in the bilateral hands after circumscribed callosal infarction due to severe stenosis of the right internal carotid artery. A 53-year-old right-handed male with a previous history of diabetes mellitus was admitted to our hospital with a diagnosis of cerebral infarction. Neurolopsychological examination revealed several inter-hemispheric disconnection signs (agraphia, apraxia and tactile anomia in the left hand, left hemispatial neglect and constructional dyspraxia in the right hand) and right hemisphere signs (dressing impairment and topographical disorientation due to disorder of visuospatial cognition). Moreover, he showed several kinds of diagnositic dyspraxia. For example, he pushed the hook of the telephone with his left hand although he was holding the receiver with the right hand to call someone ; he sat on the toilet seat in the opposite direction. He showed a pathologic grasping reflex in both hands, which was more predominant in the left side. Magnetic resonance images (MRI) of the head showed acute phase infarction in the entire corpus callosum (from the genu to the splenium). Single photon emission computed tomography (SPECT) of the head revealed decreased blood flow in the right internal carotid artery area, suggesting right hemispheric dysfunction. Magnetic resonance angiography (MRA) showed severe stenosis of the right internal carotid artery. We can find no previous case study showing both diagonistic dyspraxia and pathologic grasping reflex.We thought that in our case the combination of callosal lesion and diffuse right hemispheric dysfunction contributed to the emergence of diagonistic dyspraxia and pathologic grasping reflex.

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   In this paper we studied the relationship between long-term prognosis and lesion sites in aphasic patients without anarthrie. The subjects were 25 right-handed aphasic patients without anarthrie whose progress we could monitor for at least two years after onset. The etiology of all the subjects was cerebral infarction. The subjects were divided into three groups according to general scores on the Standard Language Test of Aphasia (SLTA) at the point when performance reached a plateau, i.e., high score group, middle score group, and low score group. In each subject, lesions in 12 brain areas and three types of generalized brain damage—cortical atrophy, ventricular dilatation (VD) , and lacunar infarct—were studied by MRI and/or CT. The results showed the proportions of subjects with lesion in Broca's area and/or inferior temporal gyrus and those with VD and/or lacunar infarct were significantly higher in the low score group than in the middle or high score groups. These findings suggest that 1) forward and/or back-downward extension of the lesion site and 2) dysfunction of the residual brain arising from subcortical pathology hinder recovery from aphasia without anarthrie in the form of internal language disorders.

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  We studied how gasoline-olfactory stimulation affects performance of language tasks.
   Twenty-two normal Japanese subjects (10 male and 12 female) were studied in several language tasks under or in absence of gasoline-olfactory stimulation, which was given immediately before and during the experiment. We devised 4 language tasks, i. e., 1 ) lexical decision, 2 ) semantic association task, 3 ) rhyme judgment task, and 4 ) assembling phonemes to make words. We calculated the percentages of correct responses and the reaction times of verbal responses in these language tasks. Gasoline stimulation appeared to accelerate verbal response in almost all of these tasks. These findings suggest that gasoline-olfactory stimulation may exert a facilitative effect on performance of language tasks.

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   The subject was a 73-year-old, right-handed male, a high school graduate, who showed alexia with agraphia in Kanji (Japanese morphograms) reading and writing following a left posterior inferior temporal lobe infarction. In the acute phase, he could not read or write Kanji or Kana. One month after onset, he was able to read and write Kana but not Kanji. Evaluation made two months after onset, using the Test of Lexical Processing in Aphasia (TLPA), showed he could write and read the Kanji which are taught in the first two years of primary school in Japan.
   The patient's alexia with agraphia was characterized as follows. With regard to reading, he showed impaired ON-reading (changed KUN-reading) in two-Kanji words. The most error types were non-responses regarding writing. He tended to have difficulty with Kanji which were more complex and had been learned later. Regarding word attributes, his writing deficit in Kanji was associated with ease of word learning, complexity, and grade learned. There were no associations with word imageability or concreteness. On the other hand, he made minor mistakes in reading and writing Kana letters.
   These results suggest that there is much more significant difficulty in writing than in reading Kanji. Therefore, pure agraphia of Kanji might combine with alexia in the present case.

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   We experienced the case of a 59-year-old male who had originally suffered from aphasia after cerebrovascular disease in his left hemisphere, sustained good recovery through eight years, but then suffered extreme deterioration of almost all language functions after a subsequent attack in his right hemisphere. From a study of his clinical course and comparison of the lesions after the first and second attacks using MRI and SPECT, we speculated that the contra-lateral hemisphere, here the right hemisphere, had contributed to his functional recovery from aphasia during the eight years after the first attack. In addition, our findings were thought to support recent functional neuro-imaging studies which propose that the contra-lateral hemisphere is thought to play important roles infunctional recovery from chronic aphasia.

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   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.

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   Unilateral spatial neglect (USN) in drawing is observed in patients with even mild brain damage. The purpose of this study is to investigate whether distortion is observed in the task of character writing by stroke patients. As it is impossible to examine slight distortion of handwriting without the aid of a device, we utilized a personal computer for this procedure to reveal possible distortions. The subjects included in this study were 44 right-handed patients who had suffered a stroke but had no significant USN or paralysis, and 53 normal participants. Two “kanji” characters were chosen as writing tasks because of their symmetrical and simple structures. The participants

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A case of neologistic jargon was reported. The subject was a 52-year-old right-handed male who suffered from fluent aphasia with neologistic jargon speech after re-attack of cerebral infarction. In this case, it seemed that the appearance of neologisms was task-dependent : that is, neologism was less prominent in comparatively implicit tasks, i. e., spontaneous speech and/or picture description in which target words were less restrictive, than in comparatively explicit tasks, i. e., confrontation naming and/or enumeration of object names in which target words were restricted and circumlocution was not allowed. In consideration of this task dependency, we administered Promoting Aphasics' Communicative Effectiveness (PACE) program in order to inhibit the appearance of neologism. As a result, his performances in the Standard Language Test of Aphasia (SLTA) revealed that although subtests involving naming of objects drawn in a picture and enumeration of animal names did not change, subtests involving explanation of activities in a picture and explanation of a comic strip showed good recovery. On the basis of these results, we discussed the underlying mechanisms of neologism in this case as well as theoretical background concerning PACE, from the standpoint of automatico-voluntary dissociation.

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