Cases reported "Apraxias"

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1/82. Dyspraxia in a patient with corticobasal degeneration: the role of visual and tactile inputs to action.

    OBJECTIVES: To investigate the roles of visual and tactile information in a dyspraxic patient with corticobasal degeneration (CBD) who showed dramatic facilitation in miming the use of a tool or object when he was given a tool to manipulate; and to study the nature of the praxic and neuropsychological deficits in CBD. methods: The subject had clinically diagnosed CBD, and exhibited alien limb behaviour and striking ideomotor dyspraxia. General neuropsychological evaluation focused on constructional and visuospatial abilities, calculation, verbal fluency, episodic and semantic memory, plus spelling and writing because impairments in this domain were presenting complaints. Four experiments assessed the roles of visual and tactile information in the facilitation of motor performance by tools. Experiment 1 evaluated the patient's performance of six limb transitive actions under six conditions: (1) after he described the relevant tool from memory, (2) after he was shown a line drawing of the tool, (3) after he was shown a real exemplar of the tool, (4) after he watched the experimenter perform the action, (5) while he was holding the tool, and (6) immediately after he had performed the action with the tool but with the tool removed from his grasp. Experiment 2 evaluated the use of the same six tools when the patient had tactile but no visual information (while he was blindfolded). Experiments 3 and 4 assessed performance of actions appropriate to the same six tools when the patient had either neutral or inappropriate tactile feedback-that is, while he was holding a non-tool object or a different tool. RESULTS: Miming of tool use was not facilitated by visual input; moreover, lack of visual information in the blindfolded condition did not reduce performance. The principal positive finding was a dramatic facilitation of the patient's ability to demonstrate object use when he was holding either the appropriate tool or a neutral object. Tools inappropriate to the requested action produced involuntary performance of the stimulus relevant action. CONCLUSIONS: Tactile stimulation was paramount in the facilitation of motor performance in tool use by this patient with CBD. This outcome suggests that tactile information should be included in models which hypothesise modality specific inputs to the action production system. Significant impairments in spelling and letter production that have not previously been reported in CBD have also been documented.
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keywords = visual
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2/82. Electromagnetic articulography treatment for an adult with Broca's aphasia and apraxia of speech.

    Electromagnetic articulography (EMA) was explored as a means of remediating [s]/[symbol in text] articulation deficits in the speech of an adult with Broca's aphasia and apraxia of speech. Over a 1-month period, the subject was provided with 2 different treatments in a counterbalanced procedure: (1) visually guided biofeedback concerning tongue-tip position and (2) a foil treatment in which a computer program delivered voicing-contrast stimuli for simple repetition. Kinematic and perceptual data suggest improvement resulting from visually guided biofeedback, both for nonspeech oral and, to a lesser extent, speech motor tasks. In contrast, the phonetic contrast treated in the foil condition showed only marginal improvement during the therapy session, with performance dropping back to baseline 10 weeks post-treatment. Although preliminary, the findings suggest that visual biofeedback concerning tongue-tip position can be used to treat nonspeech oral and (to a lesser extent) speech motor behavior in adults with Broca's aphasia and apraxia of speech.
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keywords = visual
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3/82. A category-specific deficit of spatial representation: the case of autotopagnosia.

    Following a vascular lesion in the parietal cortex of the language dominant hemisphere (right in one case), two patients showed a striking dissociation between spared naming, recognition and use of their body parts and an inability in localising on verbal command the same body parts on themselves and on a mannequin (Autotopagnosia, AT). The patients were submitted to a modified version of Reed and Farah Test (1995), a test that taps the ability to encode changes of body position as opposed to changes of position of objects. Their performance differed from normal controls, showing a specific deficit in encoding body position.It is suggested that AT could be the consequence of a lesion in a specific neural circuit, located in the language dominant hemisphere, whose function is to encode the body position for both oneself and others.
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ranking = 1.030319316106
keywords = cortex
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4/82. Neglect and constructive disorder.

    A 61 year-old right handed man, who suffered from right cerebral infarction with evidences of visual-spatial neglect and constructive disorder, was reported. When copying simple geometric designs, he omitted to copy figures on the left side of the page; he tended to bisect the line to the right of the line's real center; after memorizing the familiar pictures he mainly mentioned the pictures on the right side of the page; when copying the "Rey Complex" he also ignored the structures on the left side. The relations of the neglect and construction disorder are discussed.
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keywords = visual
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5/82. Portal systemic encephalopathy presenting with dressing and constructional apraxia.

    We report a case with portal systemic encephalopathy who presented with dressing and constructional apraxia and subtle weakness of the left hand. We initially suspected a cerebrovascular attack in the right cerebral hemisphere, but brain T1-weighted magnetic resonance (MR) imaging revealed high intensity in the basal ganglia and hyperammonemia was detected. We performed abdominal MR angiography, which visualized an intrahepatic portal systemic shunt. Cerebral blood flow, measured by xenon-enhanced computed tomography, was decreased in the bilateral, but more dominantly right-sided, parietal watershed regions. We speculate that these boundary territories might be susceptible to damage by toxic metabolites of hepatic encephalopathy.
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keywords = visual
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6/82. Dissociation between distal and proximal left limb agraphia and agraphesthesia in a patient with a callosal disconnection syndrome.

    A few neuropsychological studies have suggested the existence of bilateral hemispheric representations for the proximal parts of the limbs in humans. We report the case of a patient who presented with a callosal disconnection syndrome, which at a later stage of disease became restricted to left agraphia, left agraphesthesia and left auditory extinction. The anomic character of the agraphesthesia was demonstrated. Tactile naming was normal, which allows us to conclude that separate callosal pathways related to the left language areas transmit information for graphesthesia and tactile naming. agraphia and agraphesthesia were not observed when the proximal part of the left upper limb was utilized. These observations support the conclusion that writing and graphesthesia with the proximal part of the limb can be mediated by the ipsilateral cortex.
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ranking = 1.030319316106
keywords = cortex
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7/82. Pseudodystonic hand posturing contralateral to a metastasis of the parietal association cortex.

    A 56 year-old patient, with a history of surgically removed breast cancer three years earlier, presented with incoordination of hand movements while playing piano. Neurological examination disclosed mild position sensory loss and limb-kinetic apraxia of the distal part of the right upper extremity. The most conspicuous neurological sign was a dystonic posturing of the right hand, which was only elicited when the patient outstretched her arms with the eyes closed. MRI revealed a metastatic lesion involving the left parietal cortex. The association of focal dystonic postures with lesions of the parietal association cortex indicates that dystonia may feature damage of brain cortical areas far from the basal ganglia. In addition, this provides support to the hypothesis that impairment of sensory pathways may play a role in the origin of some hyperkinetic movement disorders, such as dystonia and athetosis.
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ranking = 6.181915896636
keywords = cortex
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8/82. Phonological agraphia following a focal anterior insulo-opercular infarction.

    Following a unique infarction, restricted to the left anterior insula and the adjacent part of the intrasylvian frontal opercular cortex, an 83-year-old right-handed patient acutely developed a severe speech disorder that evolved into mere mutism within a few hours. After rapid recovery from mutism, oral language was characterized by severe apraxia of speech. In-depth language investigations further disclosed an isolated, highly selective disturbance of the spelling system (phonological agraphia) which resolved rapidly. One year after onset of neurological symptoms, the apraxia of speech had almost completely receded. The anatomoclinical findings in this first representative of pure and nearly isolated phonological agraphia complement previous neuroanatomical and neurolinguistic accounts of phonological agraphia. The data not only seem to enrich current insights in the anatomical locus for phonological agraphia, they also seem to contribute to a further delineation of the insular role in phonologically mediated aphasic manifestations.
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ranking = 1.030319316106
keywords = cortex
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9/82. Conflict of intentions due to callosal disconnection.

    OBJECTIVES: Three patients with callosal syndrome manifested a peculiar symptom in that they were unable to perform intended whole body actions because another intention emerged in competition with the original one. Attempts were made to clarify the symptomatology of this manifestation and its possible mechanism is discussed. methods: The three patients are described and previous reports on patients with callosal damage were reviewed. Four additional patients with similar symptoms were found and the clinical features common to all seven patients were examined. RESULTS: This symptom could not be attributed to unilateral movement disorders such as unilateral apraxia, intermanual conflict, or compulsive manipulation of tools. The manifestations included marked hesitation in initiating actions, interruption of actions, repetitive actions, and performance of unintended actions with difficulty in correcting them. All patients, except one, had a lesion in the posterior half of the body of the corpus callosum, and there was no significant involvement of the cerebral cortex. The symptom became manifest later than 4 weeks after callosal damage. It occurred during spontaneous actions, but not during well automated actions nor when following instructions. CONCLUSION: This symptom, tentatively named "conflict of intentions", can be regarded as a fragment of diagonistic dyspraxia originally described by Akelaitis, although it can occur independently of intermanual conflict. Normally, the right and left cerebral hemispheres may be complementarily modifying automated whole body actions in order to adapt behaviour to changes of the environment as well as to the intention. Partial callosal disconnection without significant cortical involvement would exaggerate the disparity between the role of each hemisphere through the reorganisation of neural systems after callosal damage. Such double, often contrary, behavioural tendencies may sometimes simultaneously enter the patient's awareness.
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ranking = 1.030319316106
keywords = cortex
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10/82. Imitation of gestures by disconnected hemispheres.

    PU's corpus callosum was severed as a sequel of bleeding from an arteriovenous malformation. The lesion affects the truncus and the splenium and caused somatosensory and visual disconnection of the hemispheres. On clinical testing PU's left hand was apraxic for pantomime of object use but not for imitation. By contrast, when stimuli for imitation of meaningless hand and finger postures were presented tachistocopically to either the left or the right visual field, both hemispheres turned out to be apraxic in different ways. Imitation of hand postures was perfect for right-handed imitation of stimuli presented to the left hemisphere but defective in all other conditions. Imitation of finger postures was below the normal range in all conditions initially, but improved to normality for right-hand imitation of stimuli presented to the left hemisphere after repeated testing. After successful imitation of gestures presented to the left hemisphere PU commented that he imitated without really seeing the stimulus by "formulating the unseen", whereas after presentation to the right hemisphere he felt that he saw the stimulus but could not imitate. We propose that imitation of meaningless gestures affords a coding of gestures with reference to knowledge about body parts which can be applied only by the left hemisphere. Imitation of finger postures puts additional demands on fine grained visuospatial discrimination which necessitates a contribution by the right hemisphere.
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keywords = visual
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