Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0003635 (apraxia)
 2,817 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied 27 patients with acute stroke and a corresponding infarct in the anterior cerebral artery territory, as disclosed using computed tomography. Patients were selected from 1490 patients (1.8%) admitted consecutively to a community-based primary care center who underwent standard investigations. An embolic phenomenon from the internal carotid artery or from the heart explained the infarct in 17 patients (63%). Anterior cerebral artery occlusion without a potential source of embolism was found only in one Vietnamese patient. Neurologic features correlated well with the topography and size of infarct, including hemiparesis, hemihypesthesia, mutism at onset, transcortical motor aphasia, conflictual tasks impairment, mood disturbances, and, more uncommonly, incontinence, grasp reflex, hemineglect, acute confusional state, and unilateral left apraxia. These findings suggest that the etiologic spectrum of anterior cerebral artery infarcts is the same as that of middle cerebral artery infarcts.
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PMID:Anterior cerebral artery territory infarction in the Lausanne Stroke Registry. Clinical and etiologic patterns. 230 85

Neuropsychological changes following corpus callosotomy depend on the degree of the callosal section, the portion sectioned and the patient's age at the time of the surgery. Anterior section frequently results in transient hemiparesis of the non-dominant leg and temporary difficulties in initiating speech. Posterior section is followed by disconnection symptoms in the sensory modalities which can be demonstrated when input is lateralized and one hemisphere is denied access to the information received by the other. Visual and tactile stimuli presented to the non-dominant hemisphere are no longer verbally identified due to disconnection from the language-dominant hemisphere. Total callosotomy additionally interrupts interhemispheric communication between the motor regions. This results in deficits in bimanual coordination and apraxia of the non-dominant hand to verbal commands. Some of the symptoms subside, probably due to increased use of ipsilateral sensory and motor pathways. Others are permanent. However, they are not disabling since unrestricted scanning of the environment ensures bilateral representation of sensory experience. Cognitive functions are frequently improved, although preexisting lateralized deficits may be exacerbated. Learning of new material is difficult for some patients with lateralized temporal lobe dysfunction in whom interhemispheric compensation is abolished by the surgery. Language deficits are observed mainly in patients with crossed dominance. Studies in children reveal that callosotomy performed before puberty is not followed by permanent disconnection deficits. This may be attributable to the greater neural plasticity of the immature brain.
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PMID:Neuropsychological alterations after split-brain surgery. 927 60

Anterior cerebral artery territory infarction, which affects the medial frontal lobe and anterior part of the corpus callosum, may cause disinhibitory movement and behavioral disorders. The pathophysiology of disinhibitory movement and behavioral disorders was discussed in relation to the role of the frontal lobe in motor control and hemispheric asymmetry of motor functions. Instinctive grasp reaction is the prototype of disjunctive motor disinhibition syndromes, and diagnostic dyspraxia and compulsive manipulation of tools are the most illustrative forms. Diagnostic dyspraxia can be defined as uncontrolled cross-purposeful actions of the left hand triggered by voluntary activities of the left hand. In compulsive manipulation of tools, a patient, with the right hand, grasp and use tolls placed in front of them against the patient's will. The left hand often restrains the unintentional movement of the right hand in accordance with the patient's will. Utilization and imitation behaviors described by Lhermitte et al belong to disinhibitory behavioral disorders, in which volition of the patient or an individual as a whole is involved. External stimuli reflexively provoke the patient's will to act. The behaviors accordant with the will, even if inappropriate, are not compulsive, but the easily-raised volition in response to the stimuli is pathological. These disinhibitory disorders differ from disjunctive motor disinhibition syndromes because of lack of inconsistency between will and manifested behavior. Lesions in the frontal lobes has been suggested to be responsible for utilization and imitation behaviors.
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PMID:[Movement and behavioral disorders in anterior cerebral artery territory infarction]. 957 62