Two cases of pure agraphia following a left parieto-occipital lesion are described.
    Case 1 is a 50-year-old male afflicted by a left parieto-occipital subcortical hemorrhage ; case 2 is a 62-year-old male with a left occipital brain tumor.
    In both cases agraphia was noted in both the right and left hands. The subjects were able to express “ on-readings ” and “ kun-readings ” for Kanji characters even though they could not write them. This suggests that the auditory engram of Kanji characters was preserved. They were also able to express gross graphemic figures of Kanji and Kana characters which they could not write. This implies that visual representation of characters was also preserved. It is known that transformation from the auditory engram to the motor engram is the main pathway in the Kana-writing process. Our findings suggest that there is a pathway from auditory to visual representation and then to motor representation in the Kana-writing process, just as in the Kanji-writing process.
    The auditory and visual engrams were preserved in both cases since the Wernicke's area and the left angular gyrus were intact. Pure agraphia in both cases may reflect disruption of a pathway from the visual to the motor engrams.

View full abstract

    We report our investigations of a single patient, R. N., with lesions in the antero-inferior part of the both temoporal lobes in whom there was a relatively selective impairment of semantic memory (SM). He had no signs neuorologically, but, neuropsychologically, had a marked deficit of the use of common objects besides Korsakoff's syndromes and transcortical sensory aphasia (TSA). The deficit of the use of common objects isn't attributed to aphasia. The result of our experiment on the use of common objects showed that the error pattern of R. N. was different from the one of patients either with ideo-motor/ideational apraxia or with amnesic syndromes and that his errors were thought to be attributed to the loss of memory for the use of common objects. Taking it into account that R. N. had TSA also, we speculate that the impairment of semantic memory was reflected in his deficit of the use of common objects. Our findings didn't necessarily confirm that his impairment of SM was modality-specific and that the superordinate information was preserved, but provided some evidence that several categories were selectively preserved (category specificity).

View full abstract

     Using positron emisson tomography (PET), regional cerebral blood flow (rCBF) and regional cerebral metabolic rate of oxygen (rCMRO₂) were measured in a resting state and during a speech task, in a normal subject and two patients with slight aphasia. In the task, the subjects were instructed to recall what had happened on the day before PET from morning through night and to whisper these details sequentially. Changes in rCBF and rCMRO₂ between the resting state and the task were given as indicators of local cerebral activation induced by the task.
    In the normal subject, activations of multiple areas on both hemispheres and of the left perisylvian speech area were found. Among them, activations of both perisylvian areas and premotor and supplementary motor areas were notable. In the patients with slight aphasia, activation of the left perisylvian speech area and the lower portion of the parietal lobe were not so remarkable. But activations of the pre-motor and supplementary motor areas were preserved in patients who could perform the task.
    One patient, with left frontal malignant glioma (50-year-old, right-handed male), demonstrated loss of willingness. Activation of his left pre-frontal area was markedly suppressed. On the other hand, the other patient, with left parietal malignant glioma (62-year-old, right-handed female), was aware of her language difficulty and tried to perform the task. Her bilateral prefrontal areas were activated well. Each subject showed the presumably characteristic pattern of brain activation under his or her particular neuropsychological state.
    The task used in this study requires integration of various brain functions concerned with programming of entire performance, memory, composition of words, and motor coordination of the mouth, tongue and larynx. Therefore it activates many areas of the brain. This activation method might be a useful tool for the study of brain function not only in normal subjects but also in subjects with neurological and neuropsychological disorders.

View full abstract

     “ Haku ” is the most distinct and smallest unit in Japanese pronunciation. It is similar to a syllable but for the following characteristic : i. e., Haku refers to an articulating aspect peculiar to Japanese speech and defined as an intrinsic rhythm characterized by separation of sounds with equal intervals. Thus haku is defined by a time boundary, while a syllable is defined by a phonetical boundary. Haku constitutes a basic rhythmical element of Japanese verse. Here we report on two severe aphasic cases in which this Japanese speech rhythm was preserved. Case 1 spoke each syllable with equal intervals and with no accent. Some syllabic clusters, however, were composed of five and seven syllables, which are reminiscent of familiar meter in Japanese verse. Case 2 produced a rhythm consisting of one and two syllabic units. These two cases suggest that in prepositional language there is a stage in which the native language rhythm is independently produced, and that depending on the degree of brain damage only this stage may be preserved and expressed.

View full abstract

     The Standard Language Test for Aphasia (SLTA) was conducted on 72 aphasic patients who had suffered from brain damage for more than 3 years, for a comparative study of the level achieved on the test in relation to the lesion confirmed by CT diagnosis and the age of onset. The level expressed by the total SLTA rating score was highest in cases with lesions limited to the basal ganglia and lesions localized in the anterior (preroladic) area, followed by those with lesions localized in the posterior (postrolandic) area. The level was lowest in cases of extensive lesions and large lesions involving the basal ganglia. Many with the age of onset ≤40 years improved to a slight aphasia level. In a comparison between this group and that with an age of onset over 40 years, those with extensive lesions and lesions localized in the posterior area showed a significant difference in level of achievement. Among patients with lesions limited to the anterior area, the age of onset was associated with no significant difference in the level of achievement. Furthermore although aphasic symptoms improved remarkably, apraxia of speech persisted in this group. Among patients with lesions localized in the posterior area, on the other hand, differences in levels of achievement in tasks involving auditory comprehension or word association were found dependent on the age of onset. These findings suggest variations in plasticity of the cerebral functions. Among the patients with lesions of the basal ganglia, the achivement level varied markedly according to focal characteristics, and it might be difficult to describe their prognosis collectively as putaminal aphasia.

View full abstract

     We report a patient with the progressive aphasia syndrome strongly considered to have Alzheimer's disease. His major initial manifestation was an anomic aphasia characterized by difficulty in finding names for objects. In short, he exhibited Broca's aphasia. Examination five years after onset showed total aphasia. Nevertheless auditory comprehension of high frequency vocabulary and his emotional state were still preserved. No changes in character and personality have been seen to date, and visual cognitive function is intact.
    CT scanning disclosed a focal left perisylvian atrophy in the early stage. SPECT revealed left frontal and temporal hypoperfusion in the first year. During subsequent years, however, it showed marked hypoperfusion of the left hemisphere, with later involvement of the right hemisphere except for the occipital lobe.
    SPECT can visualize lesions earlier and correlates well with clinical features. Therefore, it is a very useful method for imaging the disturbance of characteristic cognitive.

View full abstract

     An 84-year-old right-handed woman exhibited a “ posture schema ” disorder following right fronto-parietal subcortical hematoma. She had the sensation of rotating at an angle of 90 degrees forward in her sagittal plane. This case provided some hints as to the mechanism of postural recognition.
    She showed hemiplegia and hypesthesia on her left side. A CT scan disclosed a subcortical hematoma in the right fronto-parietal junctional area. On the fourth day in hospital, she clained to feel as if she were standing, squatting or sitting vertically, but actually she was lying on her bed horizontally. In addition, she felt as if the scenery surrounding her was rotating at an angle of 90 degrees forward. This symptom continued even when she closed her eyes, but disappeared when she sat on the bed vertically. The symptom disappeared three days later. This peculiar “ postural schema ” disorder is difficult to explain by means of either a body schema disorder or impairment of visual spatial recognition. It could be postulated that a transient stimulation to the parietal association area by a subcortical hematoma had disturbed integrated processing between somatosensory, visual and vestibular information, resulting in the peculiar “ postural schema ” disorder.

View full abstract

     A case of Broca aphasia with real word recurrent utterance was reported. A 52-year-old right-handed woman sustained left putaminal hemorrhage and left parietal infarction. At the onset, she remained completely mute. At the 16th day post onset, she began to pronounce Osaete (hold it), but could not speak any other words or phrases. At one month post onset, detailed neuropsychological examination was administered, and she was diagnosed as having Broca aphasia. The recurrent utterance Osaete was pronounced fluently, while all the other words was pronounced highly non-fluently. This characteristic combination of fluency and non-fluency lasted for three and a half months. Then the recurrent utterance disappeared exactly according to the four-stage regression theory of verbal stereotype proposed by Alajouanine (1956) : (l) A stage of differentiated organization of the stereotyped verbal emissions. (2) A stage of checking the involuntary utterance. (3) A stage of fluctuating utterance. (4) A stage in which the stereotype is definitely checked and no longer occurs even occasionally. Since report of real word recurrent utterance is very few, we described the case, and discussed its aphasia type and fluency.

View full abstract