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Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of the hemispace in which writing was performed was assessed in two left hemisphere stroke patients who demonstrated left-handed mirror writing. Both patients produced significantly more mirrored words when writing in right, as compared to left (body) hemispace. We suggest that writing in the right hemispace activates the left hemisphere. Further, we propose that mirror writing in the right hemispace is attributable to activation of the damaged left hemisphere spatial system, which fails to assist in the translation of right hand motor programs into those appropriate to the left hand. Writing in left hemispace, in contrast, activates the intact right hemisphere based spatial system which guides the execution or monitoring of motor productions in left hemispace. The result is writing which remains directionally correct when the left hand is used in left hemispace.
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PMID:Hemispatial factors in mirror writing. 812 37

Mirror writing (MW) refers to the production of individual letters or whole word strings in reversed direction. When held to a mirror, these letters or words can be read normally. We observed MW in a considerable number of stroke patients. Of the 86 patients screened 15 (17.5%) showed at least one instance of mirror writing in any of the tasks. Both right (14% of 36 patients) and left (20% of 50 patients) hemisphere damaged patients produced reversed letters only when writing with their left hand, respectively the contralesional and ipsilesional hand. The dissociated performance between the two hands in brain damaged patients is relevant to the interpretation of MW because, unlike all other peripheral dysgraphias, MW affects the non-dominant hand only. Importantly, healthy elderly also showed MW solely when writing with their left hand (6.9% of 86 participants). MW in controls was less frequent but qualitatively similar to that observed in brain damaged patients. This finding is consistent with the motor interpretation of MW that assumes an inability to transform the stored letter forming programmes for left hand writing. However, several cases have been reported in the literature of a more pervasive form of MW whereby patients mirror reverse entire words or sentences. This pattern has been observed in children learning to write but it has never been observed in healthy adult volunteers. We propose that the diagnosis of MW should be limited to the reversal of whole words, multi-digit numbers and full sentences, which reveal a disorder in coding the correct direction of writing rather than an inability to accomplish the correct spatial orientation of single letters.
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PMID:Mirror writing and reversing single letters in stroke patients and normal elderly. 1738 Feb 44

Mirror writing refers to the production of individual letters, whole words or sentences in reverse direction. Unintentional mirror writing has been observed in young children and brain-damaged people and interpreted as the manifestation of different cognitive impairments. We report on a mirror writing patient following left hemisphere stroke and the mirror writing phenomena in one sample of children learning to write. We propose a unitary account of mirror writing as the unavailability of the appropriate movement direction representation, either because the right configuration has yet to be specified fully (children learning to write) or because of its damage (acquired brain injury). For this reason, we propose that the lack of directional information relevant to writing be labelled 'directional apraxia'.
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PMID:'Directional apraxia': a unitary account of mirror writing following brain injury or as found in normal young children. 1933 Oct 22

Mirror writing (MW) is a rare disorder in which a script runs in direction opposite to normal and individual letters are reversed. The disorder generally occurs after left-hemisphere lesions, is transient and is observed on the left hand, whereas usually motor impairments prevent assessment of direction of right handwriting. We describe a left-handed patient with complete left hand mirror writing, still evident 2 years after a hemorrhagic stroke in left nucleo-capsular region. Since the patient could write with his right hand he underwent several writing tasks with either hand, and a thorough assessment to clarify the nature of MW. MW was evident in writing to dictation with left hand only, both in right and left hemispace, but the patient could modify his behavior when a verbal instruction was provided. No mirror errors were found in reading words, in copying geometric figures and in spatial orientation tasks. MW in our patient could be accounted for by a failure in automatic transformation of grapho-motor programs to write with the left hand. A lack of concern (a sort of anosodiaphoria) and a poor cognitive flexibility could contribute to long-term persistence of MW.
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PMID:Persistent left unilateral mirror writing: A neuropsychological case study. 2047 78

Buchwald (1878 ) used the term 'mirror writing' to indicate writing in the reverse direction to what is normal in a particular language and in which the individual letters are also reversed. Cases of healthy individuals (i.e., Leonardo da Vinci and Lewis Carroll) as well as brain-damaged patients have been described in the literature. Here, we report the case of PM, a 70-year-old right-handed woman who showed right hemiplegia and mirror writing following a stroke in the left lenticular nucleus and internal capsulae. PM underwent a complete neuropsychological evaluation, which included copying, dictation and spontaneous writing in both hemispaces with both hands. She was also tested for topographical disorientation, visuo-spatial disorders and body schema deficits. We observed isolated mirror writing only when PM wrote with the left hand, without differences between hemispaces. She also showed a left-right disorientation, a body topological map disorder and an egocentric misrepresentation. The presence of mirror writing not confined to one hemispace and the co-presence of executive function disorders, as well as anosognosia, suggests damage to our patient's sub-cortical frontal network. As no previous interpretation fits with PM's symptoms, we hypothesize that mirror writing resulted from damage to her egocentric frame of reference. This hypothesis allows us to interpret the patient's array of disorders, including mirror writing, body topological map disorder, left-right confusion and egocentric representation.
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PMID:Mirror writing resulting from an egocentric representation disorder: a case report. 2183 Aug 64

We report a case of a right-handed Caucasian woman who developed mirror writing following a non-aneurysmal, non-traumatic subarachnoid haemorrhage. The patient was unaware of having this phenomenon, and it was detected by clinical staff when the patient was writing a card to a family member. Serial imaging has ruled out a stroke as well as an underlying vascular abnormality. This phenomenon resolved after two months. Whilst there is a body of literature surrounding mirror writing, to our knowledge, this is the first description of mirror writing in the setting of a perimesencephalic subarachnoid haemorrhage.
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PMID:Mirror writing after perimesencephalic subarachnoid haemorrhage. 3095 57

This study investigated the grapho-motor patterns used in writing Chinese characters. A Chinese patient, CSC, who demonstrated post-brain-injury mirror writing, was recruited. In Experiment 1, non-mirrored writing responses were obtained when CSC was instructed to copy asymmetrical non-verbal symbols and pictures. Resembling the patterns observed in a patient's writing reported in a previous study, it was hypothesized that CSC's mirror writing was a result of untransformed preserved grapho-motor patterns. In Experiments 2 and 3, CSC was further instructed to copy real Chinese characters, pseudo-characters with authentic radicals and logographemes (i.e., stroke clusters that frequently occur in radicals), and Hangul characters with stroke clusters resembling the shapes of authentic logographemes. The results showed that CSC demonstrated mirror writing only when authentic Chinese orthographic units were involved. Non-mirrored writing responses were obtained from stimuli without authentic Chinese orthographic units. In sum, CSC's performance supported the existence of grapho-motor patterns of Chinese orthographic units represented in the brain. Theoretical implications were discussed.
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PMID:Representations of grapho-motor patterns unique to Chinese character writing: evidence from a patient with mirror writing. 3103 2