1/515. Memories are made of this: the effects of time on stored visual knowledge in a case of visual agnosia.We report the effects of the passage of time on the longterm visual knowledge for objects in a patient with visual agnosia (H.J.A.). The naming of real objects was found to have improved, although this was not associated with any change in H.J.A.'s basic perceptual abilities which were stable over a 16-year period. The improvement in object naming was attributed to better use of non-contour-based visual information (such as surface detail and depth cues). In addition, we demonstrate a deterioration in H.J.A.'s long-term memory for the visual properties of objects, and argue that this has occurred as a result of his having impaired perceptual input. The deterioration was only apparent in drawing from memory and in the verbal descriptions of items; with forced-choice testing, H.J.A. operated at ceiling; we propose that current tests of visual imagery may not be sufficiently sensitive to detect subtle impairments of visual memory. Our findings can be taken to indicate that perceptual and memorial processes are not functionally independent, but are linked in an interactive manner.- - - - - - - - - - ranking = 1keywords = ms (Clic here for more details about this article) |
2/515. Does vestibular stimulation activate thalamocortical mechanisms that reintegrate impaired cortical regions?Caloric stimulation induced a transient reversal of multimodal hemispatial cognitive deficits in an 81-year-old woman with an acute left cerebral hemisphere stroke. The patient had unawareness of her right hand (asomatognosia), right-sided visual unawareness (hemineglect), aphasia and right-sided weakness (hemiplegia) prior to the stimulation. Transient improvements in impaired sensory, motor, linguistic and cognitive function developed within 30 s following application of the caloric stimulus and onset of horizontal nystagmus. The effect persisted for 3 min and ceased completely after 5 min. While several recent reports have described the capacity of caloric stimulation to transiently improve or reverse a wide range of attentional, cognitive and motor impairments, most examples are in right-hemisphere-damaged patients with long-standing brain injury. Typically, patients have been tested several months or years after the onset of the deficit. A possible mechanism for the temporary reintegration of multiple cognitive functions in this patient is discussed.- - - - - - - - - - ranking = 4keywords = ms (Clic here for more details about this article) |
3/515. occupational therapy. Making stroke patients feel at home.stroke may be one of the results of heart disease. stroke victims returning from the hospital face obstacles they did not imagine even during rehabilitation therapy in the hospital.- - - - - - - - - - ranking = 1keywords = ms (Clic here for more details about this article) |
4/515. Pathological jealousy appearing after cerebrovascular infarction in a 25-year-old woman.OBJECTIVE: To report pathological jealousy (Othello syndrome) occurring in a young woman with a right hemisphere cerebrovascular infarction and to review diagnosis and possible organic mechanisms for the generation of this syndrome. CLINICAL PICTURE: A 20-year-old woman was admitted to hospital with a right hemisphere stroke associated with a history of severe migraine and the use of oral contraceptives. The patient made a good recovery with minimal neurological deficits but 5 years later developed the syndrome of morbid jealousy with depression and a near fatal overdose. TREATMENT AND OUTCOME: Morbid jealousy subsided, almost completely disappearing over a 6-week period of treatment with a selective serotonin re-uptake inhibitor (SSRI). CONCLUSIONS: case reports of the Othello syndrome and other content specific delusions following right hemisphere cerebrovascular infarction have appeared in geriatric psychiatry literature. The occurrence of a similar association in a young patient lends support to the suggestion of a causal relationship and has implications for diagnosis, clinical care and research.- - - - - - - - - - ranking = 1keywords = ms (Clic here for more details about this article) |
5/515. The bare bones of object recognition: implications from a case of object recognition impairment.Three experiments were designed to investigate the performance of a patient (RK) who could name objects when presented in conventional views but showed catastrophic failures in identification from unconventional views. The aim of all three experiments was to assess the properties of the central representations that allow recognition of objects presented in conventional but not unconventional views. All three experiments showed that RK had problems in object identification not apparent from his naming performance. In the first experiment, RK was found to be extremely impaired at recognising the parts of objects even though he could name the whole object. In the second experiment, alterations in colour, shape and parts of objects were undetected in stimuli that he could name. In the third experiment, RK showed considerable difficulty with mirror-images and inversion tasks. The explanation for RK's impaired object recognition could not be attributed to defects to his early visual processing. We argue that RK's recognition is achieved through abstract (object-centred) representations that are global rather than local, and quite independent of their spatial framework. These abstract representations we take to be the essential bare bones for object recognition.- - - - - - - - - - ranking = 1keywords = ms (Clic here for more details about this article) |
6/515. Complete mutism after midbrain periaqueductal gray lesion.Several neurophysiological studies have highlighted the role of the midbrain periaqueductal gray matter (PAG) in the initiation of vocalization in various animal species, from frogs to primates. With regard to humans, only two cases of complete mutism following a lesion to the PAG have been reported so far. This article describes a new case of a patient (GM) who, following an ischemic lesion to the periaqueductal gray region of the midbrain, presented with complete and irreversible mutism, though her language comprehension functions and her non-verbal expression capacity were preserved. This clinical case provides evidence that in humans the PAG also acts as a link between different vocalization-eliciting external and internal stimuli (which reach the PAG from sensory and emotional structures) and the vocal-motor coordinating mechanisms in the lower brain stem.- - - - - - - - - - ranking = 1keywords = ms (Clic here for more details about this article) |
7/515. Persistent kluver-bucy syndrome after bilateral thalamic infarction.OBJECTIVE: To describe a patient who exhibited a partial kluver-bucy syndrome after small bilateral ischemic lesions in the thalami. BACKGROUND: Previously reported patients with kluver-bucy syndrome had very large, mostly bilateral lesions in the limbic system and could not provide sufficient information about its anatomo-functional correlate. METHOD: Behavioral assessments and clinical examinations, including magnetic resonance imaging and positron emission tomography, were conducted. RESULTS: The patient was severely amnestic, distractible, hyperoral, and affectively dyscontrolled, and she behaved socially inappropriately. magnetic resonance imaging showed bilateral infarctions in the territories of both thalamoperforating arteries, and positron emission tomography revealed bilaterally decreased fluorodeoxyglucose uptake in the anterior parts of the ventral thalami and, to a lesser extent, in the fronto-temporal cortices. CONCLUSIONS: This behavioral syndrome has not yet been reported with isolated diencephalic lesions, but it has been observed after bilateral temporal lobe lesions. The authors conjecture that this syndrome resulted from a disruption of the pathways connecting the dorsomedial thalami with the prefrontal cortices and with other limbic areas, systems essential for memory and the regulation of impulses and emotions.- - - - - - - - - - ranking = 1keywords = ms (Clic here for more details about this article) |
8/515. Successful cerebral artery stent placement for total occlusion of the vertebrobasilar artery in a patient suffering from acute stroke. Case report.A 64-year-old man suffering from crescendo brainstem symptoms due to acute total occlusion of the vertebrobasilar artery was successfully treated by cerebral artery stent placement. The total occlusion of a long segment of the vertebrobasilar artery was completely recanalized by implanting two flexible, balloon-expandable coronary stents. The patient's clinical outcome 30 days later was favorable. No complications occurred during or after the procedure. This therapeutic option may prove to be a useful means to revascularize an acute total occlusion of the vertebrobasilar artery.- - - - - - - - - - ranking = 1keywords = ms (Clic here for more details about this article) |
9/515. Central pain after pontine infarction is associated with changes in opioid receptor binding: a PET study with 11C-diprenorphine.Using 18F-fluorodeoxyglucose and 11C-diprenorphine positron emission tomography (PET), we investigated alterations in glucose metabolism and opioid receptor binding in a patient with central poststroke pain, which developed after a small pontine hemorrhagic infarction. In comparison with normal databases, reduced 11C-diprenorphine binding was more accentuated than the hypometabolism on the lateral cortical surface contralateral to the symptoms, and a differential abnormal distribution between the tracers was seen in pain-related central structures. These results show that 11C-diprenorphine PET provides unique information for the understanding of central poststroke pain.- - - - - - - - - - ranking = 1keywords = ms (Clic here for more details about this article) |
10/515. Written communication in undifferentiated jargon aphasia: a therapy study.A subject, R.M.M., with a 2-year history of jargon aphasia is described. At the beginning of this study she had minimal meaningful spoken output and showed little awareness of her speech despite having relatively well-preserved auditory comprehension. Her spoken output had proved resistant to earlier periods of therapy. In contrast, R.M.M.'s written output showed some ability to access orthographic information and monitoring of this modality was shown by an acute awareness of her errors. A 3-stage therapy programme is described. This was designed to improve R.M.M.'s writing of single words and to encourage use of writing as an alternative means of communication. The initial stage of therapy aimed to increase R.M.M.'s access to written word forms by use of picture stimuli. She showed significant improvement in writing treated items in response to pictures both immediately after therapy and at re-assessment 6 weeks later. Despite the acquisition of these skills, R.M.M. failed to use them in communicative contexts. A second stage of therapy replicated the results of the first and sought to facilitate R.M.M.'s functional use of her written vocabulary by asking her to write words to spoken questions. She again showed improved written naming of the treated items and could now produce written names appropriately in a questionnaire-type assessment. Generalization of this ability extended to items that had not been trained in this way. Functional use of writing in everyday communication remained absent, however. The final stage of therapy made explicit the potential links between items which R.M.M. could now write and functional messages which they might convey. She again showed significant changes in the acquisition of new vocabulary and, encouragingly, progress was also seen in her use of the strategy in functional communication. R.M.M.'s speech is almost entirely incomprehensible. It has remained unchanged for 2 years and has not responded to therapy. Relatively well-preserved auditory comprehension and good monitoring of written output allowed therapy to effectively target a small written vocabulary. Despite significant progress in the acquisition of new items, transfer of this skill to functional communication was initially absent. Further therapy which specifically targeted the impairment causing this failure was needed before functional use was seen. The potential for treating written output in cases of jargon aphasia which have been resistant to therapy for spoken language is discussed.- - - - - - - - - - ranking = 6keywords = ms (Clic here for more details about this article) |
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