1/91. ego-syntonic alien hand syndrome after right posterior cerebral artery stroke.The alien hand syndrome classically consists of involuntary movements accompanied by a feeling of foreignness and personification of the affected limb. Autocriticism, in which patients criticize and express astonished frustration with the behavior of the autonomous limb, is a commonly noted feature. Most cases of alien hand are associated with lesions of the supplementary motor areas of the frontal lobes, the corpus callosum, or both. The authors report on a 79-year-old man who sustained a right posterior cerebral artery distribution infarction and developed alien hand syndrome in the absence of callosal involvement. Also unique is that the patient perceived the alien hand as acceptable and positive, not hostile and repugnant. This case suggests not only that the neuroanatomic regions responsible for alien hand syndrome may require re-examination, but also that its definition may need expansion.- - - - - - - - - - ranking = 1keywords = alien hand syndrome, hand syndrome, alien hand, alien, hand (Clic here for more details about this article) |
2/91. Callosal disconnection syndrome in a left-handed patient due to infarction of the total length of the corpus callosum.We report on a left-handed patient with an ischemic infarction affecting exclusively the total length of the corpus callosum. This lesion clinically correlated with an almost complete callosal disconnection syndrome as described in callosotomy subjects, including unilateral verbal anosmia, hemialexia, unilateral ideomotor apraxia, unilateral agraphia, unilateral tactile anomia, unilateral constructional apraxia, lack of somesthetic transfer and dissociative phenomena. Despite the patient's left-handedness, his pattern of deficits was similar to the disconnection syndrome found in right-handers. Our report focusses on motor dominance and praxis. We followed-up the improvement in left apraxia and investigated the ability to initiate and learn a new visuo-motor skill. The results permit two tentative assumptions: (1) that the improvement in left apraxia was due to a compensatory increase in ipsilateral proximal muscle control, and (2) that motor dominance, i.e. the competence to initiate and learn a new movement pattern, was hemispherically dissociable from manual dominance in the sense of praxis control.- - - - - - - - - - ranking = 0.00014056558519256keywords = hand (Clic here for more details about this article) |
3/91. blepharospasm and apraxia of eyelid opening in lithium intoxication.We present the case of a 72-year-old woman with a history of a bipolar mood disorder chronically treated with lithium. Upon having the dose increased, she developed an acute confusional state accompanied by blepharospasm (BS) and apraxia of eyelid opening. gait instability with frequent falls, pyramid tract signs, and postural tremor in both hands were also evident. On withdrawing lithium, symptoms remitted within 2 weeks. This patient illustrates that BS and apraxia of eyelid opening may be triggered by lithium overdose. Our case warrants the inclusion of lithium in the list of drugs liable to induce such movement disorders.- - - - - - - - - - ranking = 2.0080797884652E-5keywords = hand (Clic here for more details about this article) |
4/91. Crossed apraxia: implications for handedness.Liepmann posited that right hand preference relates to left hemisphere dominance for learned skilled movements. Limb apraxia, impairment of skilled movement, typically occurs in individuals with left hemisphere (LH) lesions. The occurrence of apraxia in right-handed individuals following right-hemisphere lesions appears to refute Liepmann's hypothesis. We studied the apraxia of a right-handed man, RF, following a right frontal lesion to determine whether his apraxia paralleled the apraxia seen following LH lesions. Results of behavioral testing indicated that, like individuals with apraxia following left frontal lesions, RF was better at gesture recognition than gesture production which was significantly impaired across tasks. Kinematic motion analyses of movement linearity, planarity, and the coupling of temporospatial aspects of movements substantiated the parallel impairments in RF and patients with LH apraxia. The impairment seen in our patient with crossed apraxia provides evidence for the fractionation of systems underlying hand preference and skilled movement.- - - - - - - - - - ranking = 0.00016064638307722keywords = hand (Clic here for more details about this article) |
5/91. Apraxia differs in corticobasal degeneration and left-parietal stroke: A case study.Corticobasal degeneration (CBD) is a progressive disorder characterized by both cortical and basal ganglia dysfunction such as asymmetrical apraxia, and akinetic rigidity, involuntary movements, and cortical sensory loss. Although apraxia is a key finding for the differential diagnosis of CBD, it has not been determined whether the features of apraxia seen in subjects with CBD are similar to those features exhibited by subjects with left-hemisphere damage from stroke. Therefore, for both clinical purposes and in order to better understand the brain mechanisms that lead to apraxia in CBD, we studied praxis in a patient with CBD and compared him to patients who are apraxic from left-parietal strokes. We used three-dimensional movement analyses to compare the features of apraxic movement. This subject with CBD was a dentist whose initial complaint had been that he "forgot" how to use his tools in the mouths of his patients. Analyses were performed on the trajectories made when using a knife to actually slice bread, and when repetitively gesturing slicing made to verbal command. Movements of the left hand, wrist, elbow, and shoulder were digitized in 3-D space. Although the CBD subject was clearly apraxic, the features of his apraxia differed markedly from those of the subjects with lesions in the left parietal lobe. For movements to command, the CBD subject showed joint coordination deficits, but his wrist trajectories were produced in the appropriate spatial plane, were correctly restricted to a single plane, and, like control subjects, were linear in path shape. However, when he was actually manipulating the tool and object, all of these aspects of his trajectories became impaired. In contrast, the deficits of the apraxic subjects with left-parietal damage were most pronounced to verbal command with their movements improving slightly although remaining impaired during actual tool and object manipulation. Unlike patients with parietal strokes, patients with CBD have degeneration in several systems and perhaps deficits in these other areas may account for the differences in praxic behavior.- - - - - - - - - - ranking = 2.0080797884652E-5keywords = hand (Clic here for more details about this article) |
6/91. 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.- - - - - - - - - - ranking = 0.004436685181542keywords = alien (Clic here for more details about this article) |
7/91. Apraxia of single tool Use.We report a 72-year-old right-handed man who showed an 'apraxia of tool use' after a cerebral infarct in the territory of the left middle cerebral artery. His apraxia of tool use was characterized by a clear dissociation between the inability to use a single tool and the ability to use plural tools. Most of the errors occurred in selecting an appropriate target where a tool is expected to be applied. Detailed examinations confirmed that his conceptual knowledge of tool use was well preserved. Furthermore, when a target of a tool was provided as a cue, he used a single tool correctly. These results suggest that his inability to use a single tool originated from his inability to evoke a target image from an actual tool.- - - - - - - - - - ranking = 2.0080797884652E-5keywords = hand (Clic here for more details about this article) |
8/91. 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.- - - - - - - - - - ranking = 2.0080797884652E-5keywords = hand (Clic here for more details about this article) |
9/91. 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.- - - - - - - - - - ranking = 2.0080797884652E-5keywords = hand (Clic here for more details about this article) |
10/91. 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.- - - - - - - - - - ranking = 0.00012048478730791keywords = hand (Clic here for more details about this article) |
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