Le lexique des verbes en dénomination orale : étude exploratoire chez l'aphasique et étude en IRMf chez le sujet sain

Our study deals with the organisation of verb lexicon in aphasics, partly through an exploratory study of oral action naming using a video stimulus, and partly through an fMRI investigation in healthy subjects. According to our results, patients with different types of aphasia experience verb production difficulties. We observed a high rate of non conventional utterances, mainly verbal, in the form of semantic approximations. In aphasiology, the study of these utterances, which are associated with semantic paraphasia and are considered as errors, is limited to a nominal framework. We emphasise that these utterances demonstrate a verb lexicon structure based on semantic proximity, and signal the existence of a cognitive flexibility in the structure of the mental lexicon. In the literature, specific verb difficulties in aphasics are associated with frontal lobe lesions, but these data have been disputed. Using fMRI, we obtained fronto-parietal activations in the more posterior regions as well as activations in the thalamo-fronto-striate loop. Our results support the recruitment of all the cerebral regions. The stimulus used in our study may have enabled access via two pathways to the representation of the sensorimotor nature of verbs via the left middle temporal gyrus and the premotor areas. Videos appear to be a more ecological evaluative tool than images for studying the lexical processing of verbs.Notre étude porte sur l’organisation du lexique des verbes chez l’aphasique, d’une part à travers une étude exploratoire en dénomination orale d’action sur support vidéo, et d’autre part à partir d’une investigation en IRMf chez le sujet sain. D’après nos résultats, les aphasiques de différents types ont des difficultés à produire des verbes, et on observe une production importante d’énoncés non conventionnels à pivot verbal : les approximations sémantiques. En aphasiologie, l’étude de ces énoncés, qu’on associe à des paraphasies sémantiques, se limite à un cadre nominal et sont considérés comme des erreurs. Nous soulignons qu’elles manifestent un mode de structuration du lexique des verbes par proximité sémantique et marquent l’existence d’une flexibilité cognitive dans la structuration du lexique mental. Dans la littérature, les troubles spécifiques du verbe, chez l’aphasique, sont associés à des lésions du lobe frontal, mais ces données sont controversées. En IRMf, nous obtenons des activations fronto-pariétales, des régions plus postérieures, et des activations de la boucle fronto-thalamo-striée. Nos résultats sont en faveur d’un recrutement d’un ensemble de régions cérébrales. Le support que nous avons utilisé permettrait d'accéder par deux voies à la représentation de la nature sensori-motrice du verbe, par le gyrus temporal moyen gauche et les aires prémotrices. Le mode vidéo semblerait être un outil d’évaluation plus écologique que le support imagé pour l’étude du traitement du lexique des verbes

Impairment of both languages in late bilinguals with dementia of the Alzheimer type

Neuropsychological theories raise the question if in late bilinguals with dementia of the Alzheimer type (DAT), the second language (L2) may be more impaired than the first (L1). We compared language performance in different tasks of oral comprehension (semantic and syntactic) and production (naming, repetition and fluency) in L1 and L2 in a group of 13 late proficient bilinguals wit DAT immersion, and a matched control group of 12 healthy late bilinguals. Two-way mixed repeated-measure ANOVAs with factors Language and Group revealed main effects of Group (p %lt; .05) indicating that DAT affects all aspects of language. There was no Group × Language interaction, suggesting that DAT affects both languages similarly. Our study thus shows that neurodegenerative diseases affect L1 and L2 in a parallel manner, particularly at the levels of semantic, lexical and syntactic processing. These results speak in favour of a shared L1 and L2 network in late bilinguals

Second language performances in elderly bilinguals and individuals with dementia: The role of L2 immersion

With the population aging and an increase in the number of senior immigrant citizens in modern societies, public health systems will be increasingly burdened with the need to deal with the care and treatment of bi- or multilingual individuals with cognitive decline and dementia. This raises complex questions such as which language is better preserved in these elderly individuals, particularly for those facing dementias. The main aim of the present investigation was to study in two groups of immigrant populations whether the first language (L1) or the second language (L2) are better preserved. For this purpose, we assessed by means of cognitive and neurolinguistics testing 20 late-bilingual individuals with neurodegenerative dementia of the Alzheimer and mixed type, and compared their results to a matched control group consisting of 19 subjects. Our results suggest that L1 is not better preserved in individuals with dementia. We report a parallel decline of second language across groups, regardless of the presence of dementia, as well as a significant correlation between language immersion and L2 relative performances (r = 0.379, p = 0.03). Moreover our data suggest that individual with dementia may have a relative sparing of syntactic L2 comprehension. These results suggest that these elderly individuals who have lived in a host country for many years, such as the subjects here investigated, may preserve similarly their L2 as much as their L1, irrespectively of the presence or absence of neurodegenerative disease, and even preserve some features of L2 processes in dementia. These results emphasize the role of immersion in language preservation

Impairment of both languages in late bilinguals with dementia of the Alzheimer type

Neuropsychological theories raise the question if in late bilinguals with dementia of the Alzheimer type (DAT), the second language (L2) may be more impaired than the first (L1). We compared language performance in different tasks of oral comprehension (semantic and syntactic) and production (naming, repetition and fluency) in L1 and L2 in a group of 13 late proficient bilinguals wit DAT immersion, and a matched control group of 12 healthy late bilinguals. Two-way mixed repeated-measure ANOVAs with factors Language and Group revealed main effects of Group (p < .05) indicating that DAT affects all aspects of language. There was no Group × Language interaction, suggesting that DAT affects both languages similarly. Our study thus shows that neurodegenerative diseases affect L1 and L2 in a parallel manner, particularly at the levels of semantic, lexical and syntactic processing. These results speak in favour of a shared L1 and L2 network in late bilingual

Verb lexicon in oral naming : exploratory study in aphasics and fMRI study in health subjects

Notre étude porte sur l’organisation du lexique des verbes chez l’aphasique, d’une part à travers une étude exploratoire en dénomination orale d’action sur support vidéo, et d’autre part à partir d’une investigation en IRMf chez le sujet sain. D’après nos résultats, les aphasiques de différents types ont des difficultés à produire des verbes, et on observe une production importante d’énoncés non conventionnels à pivot verbal : les approximations sémantiques. En aphasiologie, l’étude de ces énoncés, qu’on associe à des paraphasies sémantiques, se limite à un cadre nominal et sont considérés comme des erreurs. Nous soulignons qu’elles manifestent un mode de structuration du lexique des verbes par proximité sémantique et marquent l’existence d’une flexibilité cognitive dans la structuration du lexique mental. Dans la littérature, les troubles spécifiques du verbe, chez l’aphasique, sont associés à des lésions du lobe frontal, mais ces données sont controversées. En IRMf, nous obtenons des activations fronto-pariétales, des régions plus postérieures, et des activations de la boucle fronto-thalamo-striée. Nos résultats sont en faveur d’un recrutement d’un ensemble de régions cérébrales. Le support que nous avons utilisé permettrait d'accéder par deux voies à la représentation de la nature sensori-motrice du verbe, par le gyrus temporal moyen gauche et les aires prémotrices. Le mode vidéo semblerait être un outil d’évaluation plus écologique que le support imagé pour l’étude du traitement du lexique des verbes.Our study deals with the organisation of verb lexicon in aphasics, partly through an exploratory study of oral action naming using a video stimulus, and partly through an fMRI investigation in healthy subjects. According to our results, patients with different types of aphasia experience verb production difficulties. We observed a high rate of non conventional utterances, mainly verbal, in the form of semantic approximations. In aphasiology, the study of these utterances, which are associated with semantic paraphasia and are considered as errors, is limited to a nominal framework. We emphasise that these utterances demonstrate a verb lexicon structure based on semantic proximity, and signal the existence of a cognitive flexibility in the structure of the mental lexicon. In the literature, specific verb difficulties in aphasics are associated with frontal lobe lesions, but these data have been disputed. Using fMRI, we obtained fronto-parietal activations in the more posterior regions as well as activations in the thalamo-fronto-striate loop. Our results support the recruitment of all the cerebral regions. The stimulus used in our study may have enabled access via two pathways to the representation of the sensorimotor nature of verbs via the left middle temporal gyrus and the premotor areas. Videos appear to be a more ecological evaluative tool than images for studying the lexical processing of verbs

Le lexique des verbes en dénomination orale (étude exploratoire chez l'aphasique et étude en IRMf chez le sujet sain)

Notre étude porte sur l organisation du lexique des verbes chez l aphasique, d une part à travers une étude exploratoire en dénomination orale d action sur support vidéo, et d autre part à partir d une investigation en IRMf chez le sujet sain. D après nos résultats, les aphasiques de différents types ont des difficultés à produire des verbes, et on observe une production importante d énoncés non conventionnels à pivot verbal : les approximations sémantiques. En aphasiologie, l étude de ces énoncés, qu on associe à des paraphasies sémantiques, se limite à un cadre nominal et sont considérés comme des erreurs. Nous soulignons qu elles manifestent un mode de structuration du lexique des verbes par proximité sémantique et marquent l existence d une flexibilité cognitive dans la structuration du lexique mental. Dans la littérature, les troubles spécifiques du verbe, chez l aphasique, sont associés à des lésions du lobe frontal, mais ces données sont controversées. En IRMf, nous obtenons des activations fronto-pariétales, des régions plus postérieures, et des activations de la boucle fronto-thalamo-striée. Nos résultats sont en faveur d un recrutement d un ensemble de régions cérébrales. Le support que nous avons utilisé permettrait d'accéder par deux voies à la représentation de la nature sensori-motrice du verbe, par le gyrus temporal moyen gauche et les aires prémotrices. Le mode vidéo semblerait être un outil d évaluation plus écologique que le support imagé pour l étude du traitement du lexique des verbes.Our study deals with the organisation of verb lexicon in aphasics, partly through an exploratory study of oral action naming using a video stimulus, and partly through an fMRI investigation in healthy subjects. According to our results, patients with different types of aphasia experience verb production difficulties. We observed a high rate of non conventional utterances, mainly verbal, in the form of semantic approximations. In aphasiology, the study of these utterances, which are associated with semantic paraphasia and are considered as errors, is limited to a nominal framework. We emphasise that these utterances demonstrate a verb lexicon structure based on semantic proximity, and signal the existence of a cognitive flexibility in the structure of the mental lexicon. In the literature, specific verb difficulties in aphasics are associated with frontal lobe lesions, but these data have been disputed. Using fMRI, we obtained fronto-parietal activations in the more posterior regions as well as activations in the thalamo-fronto-striate loop. Our results support the recruitment of all the cerebral regions. The stimulus used in our study may have enabled access via two pathways to the representation of the sensorimotor nature of verbs via the left middle temporal gyrus and the premotor areas. Videos appear to be a more ecological evaluative tool than images for studying the lexical processing of verbs.TOULOUSE2-SCD-Bib. electronique (315559903) / SudocTOULOUSE2-BUC Mirail (315552102) / SudocSudocFranceF

Difficultés lexicales dans les troubles acquis et dégénératifs : Etude exploratoire des formes et fonctions de la reformulation

International audienc

Difficultés lexicales dans les troubles acquis et dégénératifs : Etude exploratoire des formes et fonctions de la reformulation

International audienc

Impairment of both languages in late bilinguals with dementia of the Alzheimer type

Neuropsychological theories raise the question if in late bilinguals with dementia of the Alzheimer type (DAT), the second language (L2) may be more impaired than the first (L1). We compared language performance in different tasks of oral comprehension (semantic and syntactic) and production (naming, repetition and fluency) in L1 and L2 in a group of 13 late proficient bilinguals wit DAT immersion, and a matched control group of 12 healthy late bilinguals. Two-way mixed repeated-measure ANOVAs with factors Language and Group revealed main effects of Group (p < .05) indicating that DAT affects all aspects of language. There was no Group × Language interaction, suggesting that DAT affects both languages similarly. Our study thus shows that neurodegenerative diseases affect L1 and L2 in a parallel manner, particularly at the levels of semantic, lexical and syntactic processing. These results speak in favour of a shared L1 and L2 network in late bilinguals