The Experts below are selected from a list of 264 Experts worldwide ranked by ideXlab platform
Yasuhisa Sakurai - One of the best experts on this subject based on the ideXlab platform.
-
kanji morphogram and kana phonogram problem in japanese alexia and Agraphia
Frontiers of neurology and neuroscience, 2019Co-Authors: Yasuhisa SakuraiAbstract:: The kanji and kana (or kanji vs. kana) problem in the Japanese language denotes the dissociation between kanji (morphograms) and kana (phonograms) in reading/comprehension and writing. Since parAgraphia of kana in a patient with amyotrophic lateral sclerosis was first reported in 1893, kanji-kana dissociation has been the central topic in Japanese aphasiology. Recent advancements in lesion-to-symptom analyses and functional imaging studies have identified some areas whose damage causes dissociative disturbances of reading or writing between kanji and kana. That is, (1) angular alexia with Agraphia causes kanji Agraphia; alexia of kana with an angular gyrus lesion is the result of a damage to the middle occipital gyrus; (2) alexia with Agraphia for kanji is caused by a posterior inferior temporal cortex (mid-fusiform/inferior temporal gyri; visual word form area) lesion, whereas pure Agraphia for kanji is caused by a posterior middle temporal gyrus lesion; and (3) pure alexia, particularly for kanji, results from a mid-fusiform gyrus lesion (Brodmann's Area [BA] 37), whereas pure alexia for kana results from a posterior fusiform/inferior occipital gyri lesion (BA 18/19).
-
frontal phonological Agraphia and acalculia with impaired verbal short term memory due to left inferior precentral gyrus lesion
Case Reports in Neurology, 2018Co-Authors: Yasuhisa Sakurai, Emi Furukawa, Masanori Kurihara, Izumi SugimotoAbstract:: We report a patient with phonological Agraphia (selective impairment of kana [Japanese phonetic writing] nonwords) and acalculia (mental arithmetic difficulties) with impaired verbal short-term memory after a cerebral hemorrhage in the opercular part of the left precentral gyrus (Brodmann area 6) and the adjacent postcentral gyrus. The patient showed phonemic parAgraphia in five-character kana nonword writing, minimal acalculia, and reduced digit and letter span. Mental arithmetic normalized after 8 months and Agraphia recovered to the normal range at 1 year after onset, in parallel with an improvement of the auditory letter span score from 4 to 6 over a period of 14 months and in the digit span score from 6 to 7 over 24 months. These results suggest a close relationship between the recovery of Agraphia and acalculia and the improvement of verbal short-term memory. The present case also suggests that the opercular part of the precentral gyrus constitutes the phonological route in writing that conveys phonological information of syllable sequences, and its damage causes phonological Agraphia and acalculia with reduced verbal short-term memory.
-
Lesion localization of non-aphasic alexia and Agraphia
Rinshō shinkeigaku Clinical neurology, 2011Co-Authors: Yasuhisa SakuraiAbstract:: The author reviews the lesion localization of non-aphasic alexia and Agraphia and proposes a new classification of alexia and Agraphia on this basis. The newly proposed alexia and Agraphia are pure alexia for kana (Japanese phonograms), or more generally pure alexia for letters, caused by a lesion in the posterior occipital area (posterior fusiform/inferior occipital gyri), and pure Agraphia for kanji (Japanese morphograms) caused by a lesion in the posterior middle temporal gyrus and also a lesion restricted to the angular gyrus. In addition, the anatomical lesions presumably responsible for the parietal apraxic Agraphia, frontal pure Agraphia and thalamic Agraphia are discussed.
-
isolated thalamic Agraphia with impaired grapheme formation and micrographia
Journal of Neurology, 2011Co-Authors: Yasuhisa Sakurai, Yukinaga Yoshida, Koki Sato, Izumi Sugimoto, Toru MannenAbstract:Two patients with isolated thalamic Agraphia are described. Both showed kanji (Japanese morphograms) Agraphia due to impaired character recall, grapheme deformity and micrographia (progressive reduction in character size during writing) after a lesion that involved the ventral lateral and ventroposterolateral nuclei. Single photon emission computed tomography with a 99mTc-ethylcysteinate dimer revealed hypoperfusion in the left precentral gyrus (Brodmann Area 6) and anterior supramarginal gyrus in both. Six months later, the extent of blood flow reduction decreased in the supramarginal gyrus in both patients and the precentral gyrus in patient 1. By this time, the writing impairment improved to nearly the normal range. Our study suggests that kanji Agraphia (corresponding to lexical Agraphia in Western countries) with poor grapheme formation and micrographia arises from a lesion in the ventral lateral and ventroposterolateral nuclei in the left thalamus. The accompaniment of poor grapheme formation and micrographia may reflect disruption of the cortico-subcortical motor circuit involving the putamen, thalamus, premotor cortex and sensorimotor cortex. It is also suggested that multiple cortical sites can be a target for secondary dysfunction that yields Agraphia in a thalamic lesion, and that the recovery of reduced cortical blood flow does not always proceed in parallel with that of Agraphia.
-
alexia and Agraphia with lesions of the angular and supramarginal gyri evidence for the disruption of sequential processing
Journal of the Neurological Sciences, 2010Co-Authors: Yasuhisa Sakurai, Masahiko Asami, Toru MannenAbstract:Abstract Objective To determine the features of alexia or Agraphia with a left angular or supramarginal gyrus lesion. Methods We assessed the reading and writing abilities of three patients using kanji (Japanese morphograms) and kana (Japanese syllabograms). Results Patient 1 showed kana alexia and kanji Agraphia following a hemorrhage in the left angular gyrus and the adjacent lateral occipital gyri. Patient 2 presented with minimal pure Agraphia for both kanji and kana after an infarction in the left angular gyrus involving part of the supramarginal gyrus. Patient 3 also showed moderate pure Agraphia for both kanji and kana after an infarction in the left supramarginal and postcentral gyri. All three patients made transposition errors (changing of sequential order of kana characters) in reading. Patient 1 showed letter-by-letter reading and a word-length effect and made substitution errors (changing hiragana [one form of kana] characters in a word to katakana [another form of kana] characters and vice versa) in writing. Conclusion Alexia occurs as “angular” alexia only when the lesion involves the adjacent lateral occipital gyri. Transposition errors suggest disrupted sequential phonological processing from the angular and lateral occipital gyri to the supramarginal gyrus. Substitution errors suggest impaired allographic conversion between hiragana and katakana attributable to a dysfunction in the angular/lateral occipital gyri.
Steven Z Rapcsak - One of the best experts on this subject based on the ideXlab platform.
-
the nature and treatment of phonological text Agraphia
Neuropsychological Rehabilitation, 2018Co-Authors: Pelagie M Beeson, Kindle Rising, Andrew T Demarco, Taylor Howard Foley, Steven Z RapcsakAbstract:ABSTRACTPhonological alexia and Agraphia are written language disorders characterised by disproportionate difficulty reading and spelling nonwords in comparison to real words. In phonological alexia, it has been shown that, despite relatively accurate reading of words in isolation, text-level reading deficits are often marked and persistent. Specifically, some individuals demonstrate difficulty reading functors and affixes in sentences, a profile referred to as phonological text alexia. In this paper, we demonstrate an analogous manifestation of the phonological impairment on text-level writing and suggest the term “phonological text Agraphia”. We examined four individuals with phonological alexia/Agraphia who also showed disproportionate difficulty writing well-formed sentences in comparison to their grammatical competence in spoken utterances. Implementation of a phonological treatment protocol resulted in significantly improved sublexical phonology skills as well as improvements in grammatical accuracy...
-
phonological alexia Agraphia reflects damage to the dorsal language pathway evidence from multimodal imaging s18 005
Neurology, 2013Co-Authors: Steven Z Rapcsak, Andrew T Demarco, Stephen M Wilson, Pelagie M BeesonAbstract:OBJECTIVE: To identify the neural substrates of phonological alexia/Agraphia using multimodal imaging, including structural MRI/CT, diffusion tensor imaging (DTI), and functional MRI (fMRI). BACKGROUND: Contemporary neuroanatomical models of language postulate a dorsal pathway specialized for mapping phonological representations to articulatory networks during speech production and tasks involving phonological working memory. Because maintenance and manipulation of sublexical phonological information plays a critical role in reading/spelling unfamiliar nonwords, we hypothesized that damage to the dorsal pathway should be associated with the clinical profile of phonological alexia/Agraphia. DESIGN/METHODS: We conducted voxel-based lesion-symptom mapping (VLSM) in a large group of post-stroke aphasic patients with MRI/CT evidence of left-hemisphere damage (n=70) who were administered a comprehensive reading/spelling battery. In a subgroup with phonological alexia/Agraphia, DTI (n=7) and fMRI data during real word and nonword reading (n=5) were also collected. RESULTS: VLSM indicated that impaired nonword reading/spelling and an enlarged lexicality effect (words > nonwords) were associated with damage to the dorsal language pathway, including posterior superior temporal gyrus, supramarginal gyrus, inferior frontal gyrus/operculum, precentral gyrus, and insula. DTI showed that patients with phonological alexia/Agraphia sustained damage to white matter tracts connecting these perisylvian cortical regions, including the superior longitudinal/arcuate fasciculus. fMRI revealed reduced activation in dorsal pathway regions compared to controls (n=8) and increased recruitment of extrasylvian cortical areas that are components of the ventral language pathway implicated in lexical-semantic processing. CONCLUSIONS: Our findings confirm that phonological alexia/Agraphia results from damage to the dorsal pathway that includes core perisylvian language areas and their connecting white matter tracts. In functional terms, the written language disorder reflects defective engagement of perisylvian cortical networks critical for processing sublexical phonological information during nonword reading/spelling and compensatory over-reliance on a lexical-semantic strategy mediated by preserved ventral pathway regions responsible for mapping phonological and orthographic representations of familiar words to their meanings. Supported by: R01 DC07646. Disclosure: Dr. Rapcsak has received personal compensation in an editorial capacity for Neuropsychological Rehabilitation. Dr. DeMarco has nothing to disclose. Dr. Wilson has nothing to disclose. Dr. Beeson has nothing to disclose.
-
a treatment sequence for phonological alexia Agraphia
Journal of Speech Language and Hearing Research, 2010Co-Authors: Pelagie M Beeson, Kindle Rising, Steven Z RapcsakAbstract:Purpose Damage to left perisylvian cortex often results in impaired phonological processing abilities with written language profiles consistent with phonological alexia and phonological Agraphia. T...
-
A Treatment Sequence for Phonological Alexia/Agraphia
Journal of Speech Language and Hearing Research, 2010Co-Authors: Pelagie M Beeson, Kindle Rising, Steven Z RapcsakAbstract:Purpose Damage to left perisylvian cortex often results in impaired phonological processing abilities with written language profiles consistent with phonological alexia and phonological Agraphia. T...
Pelagie M Beeson - One of the best experts on this subject based on the ideXlab platform.
-
the nature and treatment of phonological text Agraphia
Neuropsychological Rehabilitation, 2018Co-Authors: Pelagie M Beeson, Kindle Rising, Andrew T Demarco, Taylor Howard Foley, Steven Z RapcsakAbstract:ABSTRACTPhonological alexia and Agraphia are written language disorders characterised by disproportionate difficulty reading and spelling nonwords in comparison to real words. In phonological alexia, it has been shown that, despite relatively accurate reading of words in isolation, text-level reading deficits are often marked and persistent. Specifically, some individuals demonstrate difficulty reading functors and affixes in sentences, a profile referred to as phonological text alexia. In this paper, we demonstrate an analogous manifestation of the phonological impairment on text-level writing and suggest the term “phonological text Agraphia”. We examined four individuals with phonological alexia/Agraphia who also showed disproportionate difficulty writing well-formed sentences in comparison to their grammatical competence in spoken utterances. Implementation of a phonological treatment protocol resulted in significantly improved sublexical phonology skills as well as improvements in grammatical accuracy...
-
phonological alexia Agraphia reflects damage to the dorsal language pathway evidence from multimodal imaging s18 005
Neurology, 2013Co-Authors: Steven Z Rapcsak, Andrew T Demarco, Stephen M Wilson, Pelagie M BeesonAbstract:OBJECTIVE: To identify the neural substrates of phonological alexia/Agraphia using multimodal imaging, including structural MRI/CT, diffusion tensor imaging (DTI), and functional MRI (fMRI). BACKGROUND: Contemporary neuroanatomical models of language postulate a dorsal pathway specialized for mapping phonological representations to articulatory networks during speech production and tasks involving phonological working memory. Because maintenance and manipulation of sublexical phonological information plays a critical role in reading/spelling unfamiliar nonwords, we hypothesized that damage to the dorsal pathway should be associated with the clinical profile of phonological alexia/Agraphia. DESIGN/METHODS: We conducted voxel-based lesion-symptom mapping (VLSM) in a large group of post-stroke aphasic patients with MRI/CT evidence of left-hemisphere damage (n=70) who were administered a comprehensive reading/spelling battery. In a subgroup with phonological alexia/Agraphia, DTI (n=7) and fMRI data during real word and nonword reading (n=5) were also collected. RESULTS: VLSM indicated that impaired nonword reading/spelling and an enlarged lexicality effect (words > nonwords) were associated with damage to the dorsal language pathway, including posterior superior temporal gyrus, supramarginal gyrus, inferior frontal gyrus/operculum, precentral gyrus, and insula. DTI showed that patients with phonological alexia/Agraphia sustained damage to white matter tracts connecting these perisylvian cortical regions, including the superior longitudinal/arcuate fasciculus. fMRI revealed reduced activation in dorsal pathway regions compared to controls (n=8) and increased recruitment of extrasylvian cortical areas that are components of the ventral language pathway implicated in lexical-semantic processing. CONCLUSIONS: Our findings confirm that phonological alexia/Agraphia results from damage to the dorsal pathway that includes core perisylvian language areas and their connecting white matter tracts. In functional terms, the written language disorder reflects defective engagement of perisylvian cortical networks critical for processing sublexical phonological information during nonword reading/spelling and compensatory over-reliance on a lexical-semantic strategy mediated by preserved ventral pathway regions responsible for mapping phonological and orthographic representations of familiar words to their meanings. Supported by: R01 DC07646. Disclosure: Dr. Rapcsak has received personal compensation in an editorial capacity for Neuropsychological Rehabilitation. Dr. DeMarco has nothing to disclose. Dr. Wilson has nothing to disclose. Dr. Beeson has nothing to disclose.
-
a treatment sequence for phonological alexia Agraphia
Journal of Speech Language and Hearing Research, 2010Co-Authors: Pelagie M Beeson, Kindle Rising, Steven Z RapcsakAbstract:Purpose Damage to left perisylvian cortex often results in impaired phonological processing abilities with written language profiles consistent with phonological alexia and phonological Agraphia. T...
-
A Treatment Sequence for Phonological Alexia/Agraphia
Journal of Speech Language and Hearing Research, 2010Co-Authors: Pelagie M Beeson, Kindle Rising, Steven Z RapcsakAbstract:Purpose Damage to left perisylvian cortex often results in impaired phonological processing abilities with written language profiles consistent with phonological alexia and phonological Agraphia. T...
Toru Mannen - One of the best experts on this subject based on the ideXlab platform.
-
isolated thalamic Agraphia with impaired grapheme formation and micrographia
Journal of Neurology, 2011Co-Authors: Yasuhisa Sakurai, Yukinaga Yoshida, Koki Sato, Izumi Sugimoto, Toru MannenAbstract:Two patients with isolated thalamic Agraphia are described. Both showed kanji (Japanese morphograms) Agraphia due to impaired character recall, grapheme deformity and micrographia (progressive reduction in character size during writing) after a lesion that involved the ventral lateral and ventroposterolateral nuclei. Single photon emission computed tomography with a 99mTc-ethylcysteinate dimer revealed hypoperfusion in the left precentral gyrus (Brodmann Area 6) and anterior supramarginal gyrus in both. Six months later, the extent of blood flow reduction decreased in the supramarginal gyrus in both patients and the precentral gyrus in patient 1. By this time, the writing impairment improved to nearly the normal range. Our study suggests that kanji Agraphia (corresponding to lexical Agraphia in Western countries) with poor grapheme formation and micrographia arises from a lesion in the ventral lateral and ventroposterolateral nuclei in the left thalamus. The accompaniment of poor grapheme formation and micrographia may reflect disruption of the cortico-subcortical motor circuit involving the putamen, thalamus, premotor cortex and sensorimotor cortex. It is also suggested that multiple cortical sites can be a target for secondary dysfunction that yields Agraphia in a thalamic lesion, and that the recovery of reduced cortical blood flow does not always proceed in parallel with that of Agraphia.
-
alexia and Agraphia with lesions of the angular and supramarginal gyri evidence for the disruption of sequential processing
Journal of the Neurological Sciences, 2010Co-Authors: Yasuhisa Sakurai, Masahiko Asami, Toru MannenAbstract:Abstract Objective To determine the features of alexia or Agraphia with a left angular or supramarginal gyrus lesion. Methods We assessed the reading and writing abilities of three patients using kanji (Japanese morphograms) and kana (Japanese syllabograms). Results Patient 1 showed kana alexia and kanji Agraphia following a hemorrhage in the left angular gyrus and the adjacent lateral occipital gyri. Patient 2 presented with minimal pure Agraphia for both kanji and kana after an infarction in the left angular gyrus involving part of the supramarginal gyrus. Patient 3 also showed moderate pure Agraphia for both kanji and kana after an infarction in the left supramarginal and postcentral gyri. All three patients made transposition errors (changing of sequential order of kana characters) in reading. Patient 1 showed letter-by-letter reading and a word-length effect and made substitution errors (changing hiragana [one form of kana] characters in a word to katakana [another form of kana] characters and vice versa) in writing. Conclusion Alexia occurs as “angular” alexia only when the lesion involves the adjacent lateral occipital gyri. Transposition errors suggest disrupted sequential phonological processing from the angular and lateral occipital gyri to the supramarginal gyrus. Substitution errors suggest impaired allographic conversion between hiragana and katakana attributable to a dysfunction in the angular/lateral occipital gyri.
-
Agraphia for kanji resulting from a left posterior middle temporal gyrus lesion
Behavioural Neurology, 2008Co-Authors: Yasuhisa Sakurai, Imari Mimura, Toru MannenAbstract:Objective: To clarify whether Agraphia or alexia occurs in lesions of the left posterior middle temporal gyrus. Methods: We assessed the reading and writing abilities of two patients with this lesion using kanji (Japanese morphograms) and kana (Japanese syllabograms). Results: Patient 1 first presented with pure alexia more impaired for kana after an infarction in the left middle and inferior occipital gyri and right basal occipital cortex, and after a second infarction in the left posterior middle temporal gyrus adjoining the first lesion he showed alexia with Agraphia for kanji and worsened alexia for kana; kanji alexia recovered over the following six to 10 months. Patient 2 presented with alexia with Agraphia for kanji following a hemorrhage in the left posterior middle and inferior temporal gyri, which resolved to Agraphia for kanji at two months after onset. Kana nonword reading was also slightly impaired, but became normal by six months post-onset. In both patients, kanji Agraphia was mostly due to impaired character recall. Conclusion: The present patients demonstrate that damage to the left posterior middle temporal gyrus alone can cause Agraphia for kanji. If the adjacent mid fusiform/inferior temporal gyri (Area 37) are spared, the kanji alexia is transient.
Kenneth M. Heilman - One of the best experts on this subject based on the ideXlab platform.
-
unilateral apraxic Agraphia without ideomotor apraxia in a patient with callosal and frontal lobe lesions p3 198
Neurology, 2018Co-Authors: Tigran Kesayan, Kenneth M. HeilmanAbstract:Objective: NA Background: Injury to the areas that store the spatial-temporal movement representations required to write, or a disconnection of these engrams from the motor areas can cause apraxic Agraphia. Apraxic Agraphia along with ideomotor apraxia (IMA) of the left hand has been described from callosal lesions. We report a woman with apraxic Agraphia of her left hand who did not demonstrate IMA. Design/Methods: Case Report: A 37 year-old right-handed woman with a history of alcohol abuse developed an apraxic Agraphia of her left hand, and a limb-kinetic apraxia (LKA), a loss of precise, independent and coordinated finger movements of both hands, as determined by the coin rotation test. However, she was without an IMA. MRI imaging reveal lesions of the genu and splenium of the corpus callosum (CC) and leukoaraiosis in the frontal lobes. Results: NA Conclusions: Discussion: These CC changes may be a form of Marchifava-Bignami disease. Injury to the CC can cause left hand LKA, and LKA can impair writing. However, this woman had a LKA of both hands, but her apraxic Agraphia was limited to left hand. Diffusion tensor imaging studies have shown that patients with alcohol abuse can develop changes in the frontal white matter, and our patient did reveal some leukoaraiosis of her frontal white matter. Therefore, it is possible that frontal white matter injury was responsible for this patient’s bilateral LKA, and these white matter or callosal injuries may have also disconnected the letter spatial-temporal movement engrams from the motor areas of the right hemisphere causing an apraxic Agraphia of her left hand. However, additional studies assessing patients with alcohol abuse for LKA and apraxic Agraphia are needed Study Supported by: NA Disclosure: Dr. Kesayan has nothing to disclose. Dr Heilman has nothing to disclose.
-
unilateral apraxic Agraphia without ideomotor apraxia from a callosal lesion in a patient with marchiafava bignami disease
Neurocase, 2018Co-Authors: Tigran Kesayan, Kenneth M. HeilmanAbstract:ABSTRACTApraxic Agraphia can be caused by left hemispheric cerebral lesions in the area that contains the spatial representations of the movements required to write, from a lesion in, or connections to, the frontal premotor cortex that converts these spatial representations to motor programs (Exner’s area). A right-handed woman with Marchiafava Bignami disease and lesions of the genu and splenium of her corpus callosum had apraxic Agraphia without ideomotor apraxia of her left. A disconnection of Exner’s area in the left hemisphere from the right hemisphere’s premotor and motor areas may have led to her inability to write with her left hand.
-
progressive asymmetric apraxic Agraphia
Cognitive and Behavioral Neurology, 2008Co-Authors: Kenneth M. Heilman, Amy Coenen, Benzi M KlugerAbstract:Background/ObjectivesPatients with apraxic Agraphia cannot correctly form the letters needed to write words but can correctly spell words orally. Apraxic Agraphia (AA) is often associated with ideomotor apraxia and most commonly induced by stroke, but can be associated with degenerative diseases. In
-
treatment of a case of phonological alexia with Agraphia using the auditory discrimination in depth add program
Journal of The International Neuropsychological Society, 1998Co-Authors: Tim Conway, John C Adair, Patricia C Heilman, Leslie Gonzalez J Rothi, Ann W Alexander, Bruce Crosson, Kenneth M. HeilmanAbstract:: Phonological alexia and Agraphia are acquired disorders characterized by an impaired ability to convert graphemes to phonemes (alexia) or phonemes to graphemes (Agraphia). These disorders result in phonological errors typified by adding, omitting, shifting, or repeating phonemes in words during reading or graphemes when spelling. In developmental dyslexia, similar phonological errors are believed to result from deficient phonological awareness, an oral language skill that manifests itself in the ability to notice, think about, or manipulate the individual sounds in words. The Auditory Discrimination in Depth (ADD) program has been reported to train phonological awareness in developmental dyslexia and dysgraphia. We used a multiple-probe design to evaluate the ADD program's effectiveness with a patient with a mild phonological alexia and mixed Agraphia following a left hemisphere infarction. Large gains in phonological awareness, reading and spelling nonwords, and reading and spelling real words were demonstrated. A follow-up reassessment, 2 months posttreatment, found the patient had maintained treatment gains in phonological awareness and reading, and attained additional improvement in real word reading.
