1/71. Transcortical sensory aphasia due to a left frontal subcortical haemorrhage.A case of transcortical sensory aphasia caused by a cerebral haemorrhage in the left frontal lobe is presented. A 72-year-old right-handed woman was admitted to the hospital, with a history of acute onset of speech disturbance and headache. On initial assessment, her spontaneous speech was fluent. She had no difficulty initiating speech, articulated normally, and did not exhibit logorrhea. Her ability to repeat phonemes and short sentences (5-6 words) was fully preserved, however she had severe difficulty with visual recognition of words, and with aural comprehension at the word level, although she was able to read words aloud. Computed tomography and magnetic resonance imaging showed cerebral haemorrhage in the left frontal lobe, involving the superior and middle frontal gyrus. Single photon emission CT revealed a wider area of low perfusion over the entire left frontal lobe, including the superior, middle and inferior frontal gyrus. The aphasia symptoms, mainly poor comprehension, disappeared quickly several weeks after the event. This may have been due to a reduction in the size of the haematoma and a resolution of the oedema around the haematoma. Clinically, the transcortical sensory aphasia in this case was indistinguishable from that caused by damage to the posterior language areas. Further case reports of transcortical sensory aphasia associated with frontal lobe lesions would help to confirm whether a relatively rapid recovery is characteristic in cases such as this.- - - - - - - - - - ranking = 1keywords = speech (Clic here for more details about this article) |
2/71. brain imaging in a patient with hemimicropsia.Hemimicropsia is an isolated misperception of the size of objects in one hemifield (objects appear smaller) which is, as a phenomenon of central origin, very infrequently reported in literature. We present a case of hemimicropsia as a selective deficit of size and distance perception in the left hemifield without hemianopsia caused by a cavernous angioma with hemorrhage in the right occipitotemporal area. The symptom occurred only intermittently and was considered the consequence of a local irritation by the hemorrhage. Imaging data including a volume-rendering MR data set of the patient's brain were transformed to the 3-D stereotactic grid system by Talairach and warped to a novel digital 3-D brain atlas. Imaging analysis included functional MRI (fMRI) to analyse the patient's visual cortex areas (mainly V5) in relation to the localization of the hemangioma to establish physiological landmarks with respect to visual stimulation. The lesion was localized in the peripheral visual association cortex, Brodmann area (BA) 19, adjacent to BA 37, both of which are part of the occipitotemporal visual pathway. Additional psychophysical measurements revealed an elevated threshold for perceiving coherent motion, which we relate to a partial loss of function in V5, a region adjacent to the cavernoma. In our study, we localized for the first time a cerebral lesion causing micropsia by digital mapping in Talairach space using a 3-D brain atlas and topologically related it to fMRI data for visual motion. The localization of the brain lesion affecting BA 19 and the occipitotemporal visual pathway is discussed with respect to experimental and case report findings about the neural basis of object size perception.- - - - - - - - - - ranking = 0.46153324773893keywords = perception (Clic here for more details about this article) |
3/71. Perceiving left and imagining right: dissociation in neglect.Signor Piazza, a patient with a left parieto-occipital haemorrhage and a right thalamic stroke, showed severe right personal neglect (e.g. touching own body parts) and right perceptual neglect in tasks with (e.g. cancelling tasks) or without (e.g. description of a complex picture) motor response. He had also right-sided neglect dyslexia (including single words), without language impairments. However, the patient also presented with a clear left-sided deficit in the representational domain (e.g. imagery tasks). Signor Piazza's pattern of performance suggests dissociation between imagery and perception within the neglect syndrome.- - - - - - - - - - ranking = 0.15384441591298keywords = perception (Clic here for more details about this article) |
4/71. Auditory agnosia restricted to environmental sounds following cortical deafness and generalized auditory agnosia.We encountered a case of auditory agnosia restricted to environmental sounds, which was associated with the development of bilateral subcortical lesions after suffering a bilateral putaminal hemorrhage. The patient had a history of a putaminal hemorrhage on her left side without any major disability. Three years later, she suffered a putaminal hemorrhage on the other side. The clinical picture started with cortical deafness, then changed to generalized auditory agnosia for verbal and environmental sounds, and finally developed into auditory agnosia confined to the perception of environmental sounds. Her errors in a test of sound recognition were discriminative rather than associative in nature. Neuro-radiological examinations revealed bilateral subcortical lesions involving the fibers from the medial geniculate body to the temporal lobes after bilateral putaminal hemorrhage. This case suggested that the subcortical lesion involving bilateral acoustic radiation could cause either cortical deafness, auditory agnosia of all sounds, or auditory agnosia restricted to environmental sounds.- - - - - - - - - - ranking = 0.15384441591298keywords = perception (Clic here for more details about this article) |
5/71. Ictal abdominal pain heralding parietal lobe haemorrhage.We present an unusual case of ictal abdominal pain occurring in the setting of parietal lobe haemorrhage. The role of the somatosensory area I in pain perception is postulated.- - - - - - - - - - ranking = 0.15384441591298keywords = perception (Clic here for more details about this article) |
6/71. Cataleptic postures in thalamic hemorrhage: case report.We report a case of catalepsy associated with thalamic hemorrhage. A 72 year-old hypertensive woman had acute onset of right-sided weakness and speech disturbances. She was on anticoagulants because of aortic valve replacement. When postures were imposed, the patient maintained the left upper limb raised for several minutes, even in uncomfortable or bizarre positions. A CT scan of the head revealed a left thalamic hemorrhage. Cataleptic postures have been reported in few cases with acute stroke.- - - - - - - - - - ranking = 0.33333333333333keywords = speech (Clic here for more details about this article) |
7/71. The influence of phonological context on the sound errors of a speaker with Wernicke's aphasia.A corpus of phonological errors produced in narrative speech by a Wernicke's aphasic speaker (R.W.B.) was tested for context effects using two new methods for establishing chance baselines. A reliable anticipatory effect was found using the second method, which estimated chance from the distance between phoneme repeats in the speech sample containing the errors. Relative to this baseline, error-source distances were shorter than expected for anticipations, but not perseverations. R.W.B.'s anticipation/perseveration ratio measured intermediate between a nonaphasic error corpus and that of a more severe aphasic speaker (both reported in Schwartz et al., 1994), supporting the view that the anticipatory bias correlates to severity. Finally, R.W.B's anticipations favored word-initial segments, although errors and sources did not consistently share word or syllable position.- - - - - - - - - - ranking = 0.66666666666667keywords = speech (Clic here for more details about this article) |
8/71. Central tinnitus: a case report.We report a case of acute-onset unilateral tinnitus in a 25-year-old woman. Analysis of imaging studies indicated that the tinnitus was likely caused by an acute hemorrhage of a small cavernous angioma that was located adjacent to the contralateral primary auditory cortex. This case provides substantial support for the concept that central tinnitus might indeed represent a pathologic activation of neural networks of nonspecific auditory perception.- - - - - - - - - - ranking = 0.15384441591298keywords = perception (Clic here for more details about this article) |
9/71. Cerebellar mutism associated with a midbrain cavernous malformation. Case report and review of the literature.The authors report a case of cerebellar mutism arising from a hemorrhagic midbrain cavernous malformation in a 14-year-old boy. No cerebellar lesion was identified; however, edema of the dorsal midbrain was noted on postoperative magnetic resonance images. Dysarthric speech spontaneously returned and then completely resolved to normal speech. This case provides further evidence for the theory that involvement of the dentatothalamic tracts, and not a cerebellar lesion per se, is the underlying cause of "cerebellar" mutism.- - - - - - - - - - ranking = 0.66666666666667keywords = speech (Clic here for more details about this article) |
10/71. Palinopsia and perilesional hyperperfusion following subcortical hemorrhage.We report a patient who exhibited transient palinopsia and visual hallucinations. Disturbances initially included an auditory component and increasingly were localized to the left visual field. These events occurred during recovery from a right subcortical hematoma with left homonymous hemianopia. Single-photon emission computed tomography (SPECT) demonstrated extensive perilesional hyperperfusion involving parts of the right parietal, temporal, and occipital cortex. Perilesional hyperperfusion disappeared as the visual abnormalities diminished. We believe that excitatory neuronal activation in perilesional cortex during recovery contributed importantly to the transient abnormal perceptions.- - - - - - - - - - ranking = 0.15384441591298keywords = perception (Clic here for more details about this article) |
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