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Granular cell tumors are rare, invariably benign, and often solitary tumors, which infrequently involve the gastrointestinal tract. We report the unique presentation of a granular cell tumor of the internal anal sphincter in a 75 year-old female. The tumor was detected during investigation of new rectal bleeding and was excised using a transanal approach and sphincter repair. At five-year follow-up the patient reported normal continence to stool and flatus and demonstrated no evidence of tumor recurrence. Immunohistochemical studies cite the Schwann neural cell as the origin of the granular cell tumor. Cytoplasmic features include acidophilic, p-aminosalicylic acid-positive, diastaseresistant granules. Granular cell tumors may be located anywhere in the body, but anorectal involvement is rare. In our own search of the world literature, no other cases were reported specifically to involve the anal sphincter. Granular cell tumors are usually detected incidentally but may be symptomatic, especially when the anorectal region is involved. Symptoms include perianal discomfort and bleeding. Adequate local excision is effective for both diagnosis and treatment of anorectal granular cell tumors. Careful follow-up should be performed after excision because of the risk of recurrence.

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We report the results of a letter naming treatment designed to facilitate letter-by-letter reading in an aphasic patient with no reading ability. Patient M.R.'s anomia for written letters reflected two loci of impairment within visual naming: impaired letter activation from print (a deficit commonly seen in pure alexic patients who read letter by letter) and impaired access to phonology via semantics (documented in a severe multimodality anomia). Remarkably, M.R. retained an excellent ability to pronounce orally spelled words, demonstrating that abstract letter identities could be activated normally via spoken letter names, and also that lexical phonological representations were intact when accessed via spoken letter names. M.R.'s training in oral naming of written letters resulted in significant improvement in her oral naming of trained letters. Importantly, as M.R.'s letter naming improved, she became able to employ letter-by-letter reading as a compensatory strategy for oral word reading. M.R.'s success in letter naming and letter-by-letter reading suggests that other patients with a similar pattern of spared and impaired cognitive abilities may benefit from a similar treatment. Moreover, this study highlights the value of testing the pronunciation of orally spelled words in localizing the source of prelexical reading impairment and in predicting the functional outcome of treatment for impaired letter activation in reading.

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Models of praxis have posited two major components, production and conceptual. Conceptual praxis disorders may occur in two domains: associative knowledge (tool-action associations such as hammer pound; tool-object associations such as hammer nail) and mechanical knowledge such as knowing the advantage that tools afford. Patients with Alzheimer's disease not only have conceptual apraxia (CA) but can dissociate CA from language deficits and from praxis production deficits (ideomotor apraxia). These findings suggests that knowledge about tools (action semantics) is independent of verbal semantics as well as movement representations. To learn if conceptual praxis knowledge is stored in one hemisphere (right or left) and if associative and mechanical conceptual praxis knowledge can be dissociated, we studied 29 right-handed subjects with unilateral strokes. Ten had left-hemisphere damage with no ideomotor apraxia. Eleven had left-hemisphere damage with ideomotor apraxia. There were eight right-hemisphere-damaged controls and 10 normal controls. These subjects were given tests for conceptual apraxia. There was a significant difference between groups, the left-hemisphere group with ideomotor apraxia being most impaired on both the associative and mechanical CA tests. There was a trend for associative and mechanical knowledge to be dissociated. Although conceptual praxis representations are stored in the left hemisphere, analysis of lesion sites did not reveal where in the left hemisphere they may be stored.

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We describe an analysis of lexical processing performed in a patient with the acute onset of an isolated anomia. Based on a model of lexical processing, we evaluated hypotheses as to the source of the naming deficit. We observed impairments in oral and written picture naming and oral naming to definition with relatively intact semantic processing across input modalities, suggesting that output from the semantic system was impaired. In contrast to previous reports, we propose that this pattern represents an impairment that arises late in semantic processing prior to accessing mode-specific verbal and graphemic output lexicons. These deficits were associated with a lesion in the posterior portion of the middle temporal gyrus or area 37, an area of supramodal association cortex that is uniquely suited as a substrate for the multimodal deficit in naming.

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Recently, researchers have advocated the use of cognitive neuropsychological models as an infrastructure for efforts in language rehabilitation. In this approach, clinicians characterize language impairments in individual patients with respect to cognitive models of lexical and sentence processing. This approach contrasts with many earlier efforts in which evaluation and treatment focused on the presence or absence of aphasia viewed as a general language impairment, or on syndromes of aphasia. We consider the structure that cognitive neuropsychological models may provide in different portions of the rehabilitation process and find that this approach, when applied with methodological rigor, has practical implications for practice in aphasia assessment and treatment. In turn, some hope that data derived from clinical applications with this approach may support the modification of cognitive neuropsychological models.