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M Sugishita

Publications and source records attributed to M Sugishita.

At least 19 recordsLinked to original sources
PubMed1992

Tactile agnosia and tactile aphasia: symptomatological and anatomical differences.

Two patients with tactile naming disorders are reported. Case 1 (right hand tactile agnosia due to bilateral cerebral infarction) differentiated tactile qualities of objects normally, but could neither name nor categorize the objects. Case 2 (bilateral tactile aphasia after operation of an epidural left parietal haematoma) had as severe a tactile naming disturbance as Case 1, but could categorize objects normally, demonstrating that tactile recognition was preserved. Case 1 may be the first case of tactile agnosia clearly differentiated from tactile aphasia. CT scans of Case 1 revealed lesions in the left angular gyrus, and in the right parietal, temporal, and occipital lobes. Case 2 had lesions in the left angular gyrus and of posterior callosal radiations. Our findings suggest that tactile agnosia appears when the somatosensory association cortex is disconnected by a subcortical lesion of the angular gyrus from the semantic memory store located in the inferior temporal lobe, while tactile aphasia represents a tactual-verbal disconnection.

Aged↗
PubMed1992

A critical appraisal of neuropsychological correlates of Japanese ideogram (kanji) and phonogram (kana) reading.

Owing to the Japanese language's unique writing system, which consists of phonograms and ideograms, reading impairments of Japanese brain-damaged patients have attracted the interest of many researchers. Past case reports as well as some widely accepted handbooks and textbooks have concluded that a specific aphasia type or lesion site is associated with a particular impairment pattern of phonograms and ideograms in reading. However, the methodology and analytical procedures in previous studies were inadequate for reliable generalizations to be made. First, the test materials were unspecified or inappropriate, or the number of test items was small. Secondly, the conclusions were presented without providing individual performance data to support them. Thirdly, in associating patterns of reading impairment with lesion sites, only single cases were reported. The present investigation was designed to overcome the omissions of previous studies, and examined the ability to read 46 single phonograms and 46 single ideograms aloud in four groups of sufficiently large numbers of patients; namely, seven pure alexics, 23 Broca aphasics, 13 Wernicke aphasics, and seven patients with alexia and agraphia. Ours are the first data to demonstrate unequivocally no consistent linkage between aphasia type and the patterns of impairment of phonogram and ideogram reading. The impairment patterns were not uniform across patients even in the same aphasia group. A majority of the cases in each group showed that phonograms and ideograms were unselectively impaired. However, ideogram reading was more difficult in three cases in the pure alexia and Broca aphasia groups, respectively, and in one case in the Wernicke aphasia group. Phonogram reading was more severely disturbed in four cases among the Broca aphasics and in one case among the patients with alexia with agraphia. An apparent variability of impairment patterns characterized the Broca aphasic group. These dyslexic patterns did not appear to correlate with the site and extent of lesions identified by computerized tomography scans. Past reports linking a particular impairment pattern of phonogram and ideogram reading and a specific lesion site were studies of single cases, and their conclusions seem oversimplified. While sensory and motor dysfunctions can usually be neuroanatomically localized in individuals, impairments of certain high cortical functions, such as the reading of phonograms and ideograms, may not be correlated with damage to definite neuroanatomical structures.

Adult↗
PubMed1992

Leftward search in left unilateral spatial neglect.

The authors' previous study with an eye camera revealed that when asked to mark the centre of a line patients with left unilateral spatial neglect persist in fixating a point on its right part and place the subjective midpoint there without searching leftwards. The present study examined the patterns of leftward search of nine patients with left unilateral spatial neglect when they were required to search for the left endpoint of the line after the bisection. The patients could search leftwards beyond the subjective midpoint to place the mark at the subjective left endpoint. The initial fixation in this search always fell near the point located to the left of the subjective midpoint by the distance between the subjective midpoint and the right endpoint of the line. In patients with severe neglect the search further to the left of this point was laborious and fell short of the true left endpoint in about 80% of the trials. Our results suggest that when asked to bisect a line patients with left unilateral spatial neglect subjectively see the line as it extends equally to either side of the point where they are going to mark the subjective midpoint.

Aged↗
PubMed1992

Aphasic seizure caused by focal epilepsy in the left fusiform gyrus.

We report a patient with paroxysmal aphasia evoked by ictal epileptiform discharges localized to the left fusiform gyrus, where a small brain tumor existed. The intracranial EEG recordings during other seizures demonstrated a close functional link between the left fusiform gyrus and Wernicke's area. The patient also showed transient aphasia with electrical stimulation of the left fusiform gyrus.

Adult↗
PubMed1991

[Intelligence and language of individuals who incurred left hemisphere injury at no later than 3 years of age].

It is generally considered that damage to the brain during infancy and young childhood results in milder or different syndromes than does brain injury incurred during adulthood. However, only several past studies employed CT scans to confirm that lesions are confined to one of the two cerebral hemispheres. We examined intelligence and language skills of 5 cases, which sustained nonprogressive damage exclusively to the left cerebral hemisphere before 1 year of age, and 1 case, which incurred nonprogressive left hemisphere injury at 3 years of age. These cases were tested at 9 to 25 years of age, or 8 to 22 years after inflicting injuries. The following scales and tests, all of which are Japanese versions, were employed: the Wechsler Intelligence Scale for Children-Revised (WISC-R) to measure intelligence of 3 cases at 15 years of age or younger, the Wechsler Adult Intelligence Scale (WAIS) for 3 cases older than 15 years of age, the Western Aphasia Bettery (WAB) to measure language skills, and the shortened version of the Token Test to assess auditory comprehension skills. Upon administration of the tests, we obtained the following results: 1) Although 1 case had a large lesion in the left hemisphere, she exhibited a high IQ of 111, and was adapted well as a college student. The result suggested that large lesions, if incurred at no later than 1 year of age, may affect intelligence to only a little or negligible extent. 2) Verbal IQ generally declines from left hemisphere damage in adults. In all of our subjects, however, verbal IQ was similar to performance IQ.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Modifications of temporal lobectomy according to the extent of epileptic foci and speech-related areas.

The authors applied combined depth and subdural electrodes in patients with intractable complex partial seizures to detect the precise extent of epileptic foci and functionally map speech-related areas. The medial temporal structures were explored with depth electrodes and the lateral temporal cortex with subdural electrodes. On the speech-dominant side, electrical stimulation was given to demarcate the speech-related areas in the lateral temporal cortex. Based on these data, the extent of surgical resections was tailored to include as much of the epileptogenic areas as possible while preserving the functionally essential zones of the lateral cortex. According to the range of resection, three different approaches were employed for en bloc ablation of the lateral cortex and opening of the inferior ventricle. The results thus acquired have been satisfactory in terms of seizure control and the preservation of speech function.

Adolescent↗
PubMed1990

Improvement of unilateral spatial neglect with numbering.

We examined 8 patients with moderate to severe left unilateral spatial neglect by means of a series of line cancellation tasks. We asked the patients to cross out lines in the 1st trial, to number lines in the 2nd trial, and again to cross out lines in the 3rd trial. In the 2nd trial with numbering, all the patients showed improvement of left unilateral spatial neglect. Numbering involved the successive use of increasing numbers. This process seemed to motivate the patients to continue searching for another line, even at the point when they would be satisfied that they had completed the task if they used simple crossing-out. Insufficient motivation for visuospatial searching may play an important role in unilateral spatial neglect observed in cancellation tasks.

Aged↗
PubMed1989

Lexical agraphia in the Japanese language. Pure agraphia for Kanji due to left posteroinferior temporal lesions.

A new syndrome of 'pure agraphia for Kanji' is described in 3 Japanese subjects with lesions in the left posteroinferior temporal region. Kanji (ideogram or morphogram) can be compared with orthographically irregular or ambiguous words in some European languages, since it is impossible to write Kanji characters unless each one of them is learned and memorized. In contrast, Kana (phonogram or syllabogram) words are comparable with orthographically regular words or nonsense words, because the Kana writing system depends on strict phonological rules (almost one-to-one correspondence between syllable and syllabogram). We conclude that 'lexical agraphia' reported in European languages can also be observed in the Japanese language where it is expressed as 'pure agraphia for Kanji'. 'Lexical agraphia' is a useful concept with general application regardless of language system.

Aged↗
PubMed1989

[Interhemispheric visual information transfer in callosal agenesis].

It has been well established that acquired lesions of the corpus callosum such as surgical section bring about disturbances of interhemispheric transfer of visual information. In contrast, patients with callosal agenesis do not display these specific deficits. The mechanisms of this compensation have been postulated as follows; (1) bilateral development of language function, (2) exploitation of extracallosal commissure fibers such as the anterior commissure. Several studies have reported, however, minor disturbances of interhemispheric visual transfer in callosal agenesis, such as less efficient interhemispheric transfer of complex visual stimuli (Gott & Saul, 1978), slower reaction time in interhemispheric comparison of visual stimuli (Sauerwein & Lassonde, 1983), or deficits in spatial localization in the right hemi-field (Martin, 1985). In order to settle these issues, we have administered four kinds of tachistoscopic visual recognition tests on 4 patients with complete agenesis of the corpus callosum confirmed by magnetic resonance imaging (MRI). This technique enabled us to see the mid-sagittal plane of the corpus callosum and diagnose its total absence with much higher certainty and precision than previous studies employing computed tomography (CT) or pneumoencephalography. Case 1: A 41-year-old right-handed man visited us because of recurrent numbness in the four extremities. Neurological examination revealed no abnormalities. MRI has confirmed that the corpus callosum was totally lacking, and that the anterior commissure was normally visualized. Case 2: A 31-year-old right-handed man was referred to us for the treatment of partial complex seizure. Total agenesis and lipoma of the corpus callosum was diagnosed by MRI and reconstructed sagittal view of CT scan.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Visual processes in a hemialexic patient with posterior callosal section.

A patient with surgical section of the splenium and, probably, the posterior end of the truncus of the corpus callosum was studied 9-13 yr after the operation. His reading aloud, reading comprehension and word-matching abilities were moderately disturbed only in the left hemifield. These three disturbances were equally disturbed. The disturbances were not the result of visual disturbances such as tachistoscopic hemiamblyopia or tachistoscopic hemineglect since Landolt's ring matching was intact in the left hemifield as well as in the right. The disturbances were also not due to the disturbance of tachistoscopic word perception since the patient correctly performed same-different judgment of pairs of words in each hemifield. In his reading aloud and reading comprehension disturbances, ideogram words were less impaired than phonogram words, even when the number of letters in the words was the same. His picture naming ability was not disturbed in each hemifield.

Adult↗
PubMed1987

Alloaesthesia.

Alloaesthesia is a condition in which a sensory stimulus given on one side of the body is perceived at the corresponding area on the other side. We observed this in 20 out of 123 patients with hypertensive cerebral haemorrhage in the acute stage (within twenty days), all except 1 in the right hemisphere. This phenomenon was observed in 17 out of 35 patients with right putaminal haemorrhage and only 1 out of 30 patients with right thalamic haemorrhage, suggesting it may be useful in differentiating putaminal from thalamic haemorrhage in the right hemisphere. Three patients, with cervical tumour, cervical disc herniation and multiple sclerosis also showed alloaethesia. They had anterolateral lesions of the spinal cord. The cerebral and spinal cord lesions presented similar symptomatic characteristics of alloaesthesia. It is suggested that as alloaesthesia is produced by noxious stimuli not only in spinal cord but also in cerebral lesions it may represent an elementary sensory disturbance of sensory pathways, and not a higher cortical dysfunction.

Cerebral Hemorrhage↗