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S Carbonnel

Publications and source records attributed to S Carbonnel.

11 recordsLinked to original sources
PubMed2006

Polysyllabic pseudo-word processing in reading and lexical decision: converging evidence from behavioral data, connectionist simulations and functional MRI.

The cognitive mechanisms involved in polysyllabic pseudo-word processing -- and their neurobiological correlates -- were studied through the analysis of length effects on French words and pseudo-words in reading and lexical decision. Connectionist simulations conducted on the ACV98 network paralleled the behavioral data in showing a strong length effect on naming latencies for pseudo-words only and the absence of length effect for both words and pseudo-words in lexical decision. Length effects in reading were characterized at the neurobiological level by a significant and specific activity increase for pseudo-words as compared to words in the right lingual gyrus (BA 19), the left superior parietal lobule and precuneus (BA7), the left middle temporal gyrus (BA21) and the left cerebellum. The behavioral results suggest that polysyllabic pseudo-word reading mainly relies on an analytic procedure. At the biological level, additional activations in visual and visual attentional brain areas during long pseudo-word reading emphasize the role of visual and visual attentional processes in pseudo-word reading. The present findings place important constraints on theories of reading in suggesting the involvement of a serial mechanism based on visual attentional processing in pseudo-word reading.

Adult↗
PubMed1998

A connectionist multiple-trace memory model for polysyllabic word reading.

A connectionist feedforward network implementing a mapping from orthography to phonology is described. The model develops a view of the reading system that accounts for both irregular word and pseudoword reading without relying on any system of explicit or implicit conversion rules. The model assumes, however, that reading is supported by 2 procedures that work successively: a global procedure using knowledge about entire words and an analytic procedure based on the activation of word syllabic segments. The model provides an account of the basic effects that characterize human skilled reading performance including a frequency by consistency interaction and a position-of-irregularity effect. Furthermore, early in training, the network shows a performance similar to that of less skilled readers. It also offers a plausible account of the patterns of acquired phonological and surface dyslexia when lesioned in different ways.

Humans↗
PubMed1997

One or several semantic system(s)? Maybe none: evidence from a case study of modality and category-specific "semantic" impairment.

Following cerebral anoxia, EC a 55-year-old patient, exhibited a severe and clear-cut pattern of semantic impairments without general intellectual deficit or perceptual difficulty. EC demonstrated a complex neuropsychological picture including a massive visual agnosia and a complete lack of imagery, both of which involved all categories of objects (living and non living) and a category-specific word comprehension deficit limited to animal names. Findings are discussed in the light of the theoretical frameworks currently available in the area of neuropsychology. It is argued that neither the single nor the multiple view of semantics fully succeed in providing a satisfactory account of the data and a tentative interpretation of the whole pattern of impairment is proposed in the general framework of non abstractive conceptions of meaning.

Agnosia↗
PubMed1995

[Deficiency in the reproduction and learning proper names after left tubero-thalamic ischemic lesion].

Predominant impairment or preservation of category-specific naming and comprehension is not rare in aphasics. Much less frequent is a selective inability to generate proper names. To our knowledge, only one such case has been reported after a left thalamic lesion, located in the ventral anterior nucleus, the mamillo-thalamic tractus and the genu of the internal capsule. We report a new case of selective inability to generate proper names after a left tubero-thalamic infarct. A 65-year old right-handed man presented with a selective impairment in producing proper names, both from photographs or descriptions and on tests of verbal fluency. The deficit was obvious both for persons names and for geographical names. The rest of the neuropsychological testing was remarkable only for a mild verbal amnesia, affecting only serial material (list of words), a reduced fluency for flowers, fruits and musical instruments, difficulties in learning of new words, and a dissociation between preserved learning for words on a test of learning of words and occupations (Cohen, 1990). This anomia for proper names could result from an indirect frontal-lobe dysfunction, preventing voluntary activation of the phonological representation of proper names.

Aged↗
PubMed1990

[Memory disorders following rupture of anterior communicating artery aneurysm. 22 cases].

Twenty-two patients who underwent surgery for ruptured aneurysm of the anterior communicating artery were investigated by a battery of neuropsychological tests, including memory evaluation tests. According to the results obtained at these tests the patients were divided into three groups: 1) 7 patients had no memory disorders; 2) 10 patients presented with memory disorders affecting memory; their complaints concerned behavior, and the memory deficit was discovered at neuropsychological examination; 3) 5 patients presented with an obvious amnesic syndrome, and the tests confirmed a severe learning deficit and a severe forgetting while recognition remained normal in 4 patients. Age, residual lesions at CT and electrophysiological signs of focalization correlated well with the residual neuropsychological disorders. Leaving aside quantitative aspects, the memory deficits observed in the second and third groups seemed to be qualitatively different and might correspond to different anatomical and functional sequelae.

Adult↗
PubMed1988

Right visual hemiagnosia: a single case report.

A patient with an infarct in the territory of the left posterior cerebral artery, but without campimetric deficits presented with some reading difficulties and a visual agnosia restricted to the right visual field. Although the patient was able to match accurately in his agnosic field, he was unable to name or otherwise identify objects. The implications of this case for the anatomical substrates of visual processing and the functions of each hemisphere are discussed.

Aged↗
PubMed1987

Sinus histiocytosis with massive lymphadenopathy (Destombes-Rosai-Dorfman syndrome) occurring as a single enlarged submandibular lymph node: a light and immunohistochemical study with review of the literature.

Sinus histiocytosis with massive lymphadenopathy (SHML) is primarily a disease of children and young adults in which there is a pronounced and persistent cervical lymph node enlargement that usually is bilateral and is accompanied by fever. The histology, which varies according to the stage of the disease, is characterized by an exuberant intrasinusoidal histiocytic proliferation. The present case involves a 4-year-old girl who had several episodes of upper respiratory infection and otitis media; subsequently, a walnut-sized enlargement developed in the left anterior portion of the neck. Results of a physical examination were essentially normal. A laboratory work-up was noncontributory. Serologic tests for toxoplasmosis, infectious mononucleosis, and cat-scratch disease were negative. Immunoelectrophoresis disclosed normal values for IgG, IgM, IgA, and IgE. The histopathology was characteristic of SHML. The lymph node demonstrated pericapsular and capsular fibrosis and widely dilated subcapsular, trabecular, and medullary sinuses packed with histiocytes and plasma cells. "Lymphophagocytosis" and large atypical histiocytes resembling Reed-Sternberg cells were noted. Immunohistochemistry demonstrated a polyclonal population of plasma cells mostly stained with rabbit anti-human igG. The cytoplasm of the histiocytes, having ingested lymphocytes, was positively stained for IgG. Other groups of lymph nodes were affected during the next several months. The patient's condition has now been followed for 2 years, and the lymphadenopathy has almost completely regressed. The site distribution of the head and neck extranodal manifestations of SHML was analyzed in 54 cases.

Child, Preschool↗
PubMed1986

[Tactile and visual neglect. Preliminary study of 4 patients].

A battery of tactile tests for the study of unilateral neglect is presented with the purpose of comparing the tactile modality to the visual modality. This was applied in 4 patients with right hemisphere lesions. In 3 patients, there was evidence of neglect in both modalities with qualitatively identical anomalies. The function of spatial manipulation involved in the tasks is stressed. In the cases where both modalities were involved a supramodal hemispatial disturbance is assumed.

Aged↗
PubMedDate not supplied

[Drug prescriptions outside the marketing product license and its responsibilities].

In France, drugs are commercialized after obtaining marketing approval. There are some situations however in which clinicians are authorized to prescribe drugs outside the limits set by the approval document. Clinicians must comply with certain number of regulations. Compliance with prescription modalities, particularly precautions concerning prescription writing or the patient's informed consent, is mandatory. Although patients cannot be reimbursed for drugs prescribed outside the approval limitations, they may nevertheless benefit from special dispositions: temporary approval for use and experimentation within the framework of the Huriet law. We analyze here the question of liability in case of drug prescriptions outside approval limitations, discussing the issues of civil and penal law and patient reimbursement.

Drug Approval↗