Inter-individual variability in discourse informativeness in elderly populations.

An increasing number of studies focus on discourse production in patients with neurodegenerative diseases and underline its clinical usefulness. However, if this is to be used as a clinical tool, one needs to consider how normal discourse varies within cognitively unimpaired elderly populations. In the current study, the aim has been to investigate discourse macrolinguistic variability. For this, 123 participants aged between 55 and 84 were recruited. A cluster analysis of their discourse macrolinguistic features was conducted. Then, cluster characterisation based on socio-demographic and linguistic performance was tested (fluency, naming, syntax and spelling). This method aims to identify various profiles of speaker and informativeness and then see if inter-individual variability may be related to socio-demographic and/or linguistic aspects. Four clusters of informativeness were found but no socio-demographic features appeared significant. The fourth cluster, defined as 'off topic', had lower performance during linguistic tasks than others and thus the boundary between normality and pathology should be questioned.

The application of rules in morphology, syntax and number processing: a case of selective deficit of procedural or executive mechanisms?

Declarative memory is a long-term store for facts, concepts and words. Procedural memory subserves the learning and control of sensorimotor and cognitive skills, including the mental grammar. In this study, we report a single-case study of a mild aphasic patient who showed procedural deficits in the presence of preserved declarative memory abilities. We administered several experiments to explore rule application in morphology, syntax and number processing. Results partly support the differentiation between declarative and procedural memory. Moreover, the patient's performance varied according to the domain in which rules were to be applied, which underlines the need for more fine-grained distinctions in cognition between procedural rules.

Working memory and semantic involvement in sentence processing: a case of pure progressive amnesia.

ED, a 83-year-old woman, meets the criteria of pure progressive amnesia, with gradual impairment of episodic and autobiographical memory, sparing of semantic processing and strong working memory (WM) deficit. The dissociation between disturbed WM and spared semantic processing permitted testing the role of WM in processing anaphors like pronouns or repeated names. Results showed a globally normal anaphoric behavior in two experiments requiring anaphoric processing in sentence production and comprehension. We suggest that preserved semantic processing in ED would have compensated for working memory deficit in anaphoric processing.

Proper name anomia with preserved lexical and semantic knowledge after left anterior temporal lesion: a two-way convergence defect.

This article describes the case of a patient who, following herpes simplex encephalitis (HSE), retained the ability to access rich conceptual semantic information for familiar people whom he was no longer able to name. Moreover, this patient presented the very rare combination of name production and name comprehension deficits for different categories of proper names (persons and acronyms). Indeed, besides his difficulty to retrieve proper names, SL presented a severe deficit in understanding and identifying them. However, he was still able to recognize proper names on familiarity decision, demonstrating that name forms themselves were intact. We interpret SL's deficit as a rare form of two-way lexico-semantic disconnection, in which intact lexical knowledge is disconnected from semantic knowledge and face units. We suggest that this disconnection reflects the role of the left anterior temporal lobe in binding together different types of knowledge and supports the classical convergence-zones framework (e.g., Damasio, 1989) rather than the amodal semantic hub theory (e.g., Patterson, Nestor, & Rogers, 2007).

Relationship between the Brazilian version of the Montreal-Toulouse language assessment battery and education, age and reading and writing characteristics. A cross-sectional study.

CONTEXT AND OBJECTIVE: There is growing concern about understanding how sociodemographic variables may interfere with cognitive functioning, especially with regard to language. This study aimed to investigate the relationship between performance in the Brazilian version of the Montreal-Toulouse language assessment battery (MTL-BR) and education, age and frequency of reading and writing habits (FRWH). DESIGN AND SETTING: Cross-sectional study conducted in university and work environments in Rio Grande do Sul, Brazil. METHOD: The MTL-BR was administered to a group of 233 healthy adults, aged 19 to 75 years (mean = 45.04, standard deviation, SD = 15.47), with at least five years of formal education (mean = 11.47, SD = 4.77). RESULTS: A stepwise multiple linear regression model showed that, for most tasks, the number of years of education, age and FRWH were better predictors of performance when analyzed together rather than separately. In separate analysis, education was the best predictor of performance in language tasks, especially those involving reading and writing abilities. CONCLUSION: The results suggested that the number of years of education, age and FRWH seem to influence performance in the MTL-BR, especially education. These data are important for making diagnoses of greater precision among patients suffering from brain injuries, with the aim of avoiding false positives.

Montreal-Toulouse Language Assessment Battery: evidence of criterion validity from patients with aphasia.

BACKGROUND: The Montreal-Toulouse Language Assessment Battery - Brazilian version (MTL-BR) provides a general description of language processing and related components in adults with brain injury. OBJECTIVE: The present study aimed at verifying the criterion-related validity of the Montreal-Toulouse Language Assessment Battery - Brazilian version (MTL-BR) by assessing its ability to discriminate between individuals with unilateral brain damage with and without aphasia. METHODS: The investigation was carried out in a Brazilian community-based sample of 104 adults, divided into four groups: 26 participants with left hemisphere damage (LHD) with aphasia, 25 participants with right hemisphere damage (RHD), 28 with LHD non-aphasic, and 25 healthy adults. RESULTS: There were significant differences between patients with aphasia and the other groups on most total and subtotal scores on MTL-BR tasks. CONCLUSIONS: The results showed strong criterion-related validity evidence for the MTL-BR Battery, and provided important information regarding hemispheric specialization and interhemispheric cooperation. Future research is required to search for additional evidence of sensitivity, specificity and validity of the MTL-BR in samples with different types of aphasia and degrees of language impairment.

Syllables as units in speech production: Data from aphasia.

The syllable has received considerable empirical support as a unit of processing in speech perception, but its status in speech production remains unclear. Some researchers propose that syllables are individually represented and retrieved during phonological encoding (e.g., Dell, 1986; Ferrand, Segui, & Grainger, 1996; MacKay, 1987). We test this hypothesis by examining the influence of syllable frequency on the phonological errors of two aphasics. These individuals both had an impairment in phonological encoding, but appeared to differ in the precise locus of that impairment. They each read aloud and repeated 110 pairs of words matched for syllabic complexity, but differing in final syllable frequency. Lexical frequency was also controlled. Neither aphasic was more error-prone on low than on high frequency syllables (indeed, one showed a near-significant reverse effect), and neither showed a preference for more frequent syllables in their errors. These findings provide no support for the view that syllables are individually represented and accessed during phonological encoding.

Montreal-Toulouse language assessment battery for aphasia: validity and reliability evidence.

BACKGROUND: In Brazil, no standardized instruments are available to assess language in patients with aphasia. OBJECTIVE: The aim of the current study was to search for reliability and validity evidence for the Montreal-Toulouse Language Assessment Battery (MTL-BR). METHODS: The sample was composed of 537 adults, of whom 463 were healthy individuals and 74 had neurological lesions (25 participants had right hemisphere brain damage, 21 had left hemisphere damage (LHD) with aphasia and 28 had LHD without aphasia). Reliability was assessed by internal consistency (Cronbach's alpha) and test-retest analyses. Test-retest reliability was calculated using the Pearson correlation coefficient, and a repeated measures analysis of variance, with years of education as a covariate. Construct validity was verified by correlations between scores in MTL-BR subtest and similar tasks from other language assessment instruments. RESULTS: Internal consistency was satisfactory (Cronbach's alpha between 0.79 and 0.90), as were correlations between test and retest scores (mean 0.52), and between the MTL-BR and scores in similar instruments. CONCLUSIONS: The present results suggested that the MTL-BR battery had adequate reliability and validity as a method for diagnosing and monitoring aphasia.

Object and proper name retrieval in temporal lobe epilepsy: a study of difficulties and latencies.

PURPOSE: Retrieving a specific name is sometimes difficult and can be even harder when pathology affects the temporal lobes. Word finding difficulties have been well documented in temporal lobe epilepsy (TLE) but analyses have mostly concentrated on the study of accuracy. Our aim here was to go beyond simple accuracy and to provide both a quantitative and a qualitative assessment of naming difficulties and latencies in patients with TLE. METHODS: Thirty-two patients with temporal lobe epilepsy (16 with epilepsy affecting the cerebral hemisphere dominant for language (D-TLE) and 16 with epilepsy affecting the cerebral hemisphere non-dominant for language (ND-TLE)) and 34 healthy matched control subjects were included in the study. The experiment involved naming 70 photographs of objects and 70 photographs of celebrities as fast as possible. Accuracy and naming reaction times were recorded. Following each trial, a questionnaire was used to determine the specific nature of each subject's difficulty in retrieving the name (e.g., no difficulty, paraphasia, tip of the tongue, feeling of knowing the name, etc). Reaction times were analysed both across subjects and across trials. KEY FINDINGS: D-TLE patients showed consistent and quasi-systematic impairment compared to matched control subjects on both object and famous people naming. This impairment was characterized not only by lower accuracy but also by more qualitative errors and tip of the tongue phenomena. Furthermore, minimum reaction times were slowed down by about 70 ms for objects and 150 ms for famous people naming. In contrast, patients with ND-TLE were less impaired, and their impairment was limited to object naming. SIGNIFICANCE: These results suggest that patients with TLE, in particular D-TLE, show a general impairment of lexical access. Furthermore, there was evidence of subtle difficulties (increased reaction times) in patients with TLE.

Relationship between the Brazilian version of the Montreal-Toulouse language assessment battery and education, age and reading and writing characteristics. A cross-sectional study / Relação entre a bateria Montreal-Toulouse de avaliação da linguagem, versão brasileira, e escolaridade, idade e hábitos de leitura e escrita. Um estudo transversal

CONTEXT AND OBJECTIVE: There is growing concern about understanding how sociodemographic variables may interfere with cognitive functioning, especially with regard to language. This study aimed to investigate the relationship between performance in the Brazilian version of the Montreal-Toulouse language assessment battery (MTL-BR) and education, age and frequency of reading and writing habits (FRWH).DESIGN AND SETTING: Cross-sectional study conducted in university and work environments in Rio Grande do Sul, Brazil.METHOD: The MTL-BR was administered to a group of 233 healthy adults, aged 19 to 75 years (mean = 45.04, standard deviation, SD = 15.47), with at least five years of formal education (mean = 11.47, SD = 4.77).RESULTS: A stepwise multiple linear regression model showed that, for most tasks, the number of years of education, age and FRWH were better predictors of performance when analyzed together rather than separately. In separate analysis, education was the best predictor of performance in language tasks, especially those involving reading and writing abilities.CONCLUSION: The results suggested that the number of years of education, age and FRWH seem to influence performance in the MTL-BR, especially education. These data are important for making diagnoses of greater precision among patients suffering from brain injuries, with the aim of avoiding false positives.

CONTEXTO E OBJETIVO: Há uma preocupação crescente com o entendimento de como as variáveis sociodemográficas podem interferir no funcionamento cognitivo, especialmente na linguagem. Este estudo teve como objetivo investigar a relação entre o desempenho na Bateria Montreal-Toulouse de Avaliação da Linguagem, em sua versão brasileira (MTL-BR), e a escolaridade, a idade e a frequência de hábitos de leitura e escrita (FHLE).TIPO DE ESTUDO E LOCAL: Estudo transversal conduzido em ambientes universitários e de trabalho do Rio Grande do Sul, Brasil.MÉTODOS: A Bateria MTL-BR foi administrada em um grupo de 233 adultos saudáveis, de 19 a 75 anos de idade (M = 45,04, desvio padrão, DP = 15,47), com no mínimo cinco anos de estudo formal (M = 11,47, DP = 4,77).RESULTADOS: O modelo de regressão linear múltipla (stepwise) mostrou que, para a maioria das tarefas, os anos de escolaridade, de idade e FHLE são melhores preditores de desempenho quando analisados em conjunto do que separadamente. Quando analisada isoladamente, a escolaridade foi o melhor preditor para o desempenho nas tarefas linguísticas, principalmente nas tarefas que envolvem habilidades de leitura e escrita.CONCLUSÃO: Os resultados mostraram que os anos de escolaridade, idade e FHLE parecem influenciar o desempenho na MTL-BR, principalmente a escolaridade. Esses dados são relevantes para a realização de diagnóstico mais preciso de pacientes que sofreram lesão cerebral a fim de evitar falsos positivos.

The time-course of visual categorizations: you spot the animal faster than the bird.

BACKGROUND: Since the pioneering study by Rosch and colleagues in the 70s, it is commonly agreed that basic level perceptual categories (dog, chair...) are accessed faster than superordinate ones (animal, furniture...). Nevertheless, the speed at which objects presented in natural images can be processed in a rapid go/no-go visual superordinate categorization task has challenged this "basic level advantage". PRINCIPAL FINDINGS: Using the same task, we compared human processing speed when categorizing natural scenes as containing either an animal (superordinate level), or a specific animal (bird or dog, basic level). Human subjects require an additional 40-65 ms to decide whether an animal is a bird or a dog and most errors are induced by non-target animals. Indeed, processing time is tightly linked with the type of non-targets objects. Without any exemplar of the same superordinate category to ignore, the basic level category is accessed as fast as the superordinate category, whereas the presence of animal non-targets induces both an increase in reaction time and a decrease in accuracy. CONCLUSIONS AND SIGNIFICANCE: These results support the parallel distributed processing theory (PDP) and might reconciliate controversial studies recently published. The visual system can quickly access a coarse/abstract visual representation that allows fast decision for superordinate categorization of objects but additional time-consuming visual analysis would be necessary for a decision at the basic level based on more detailed representations.

Impact of right hemispheric damage on a hierarchy of complexity evidenced in young normal subjects.

The occurrence of a right-hemisphere lesion can interfere with pragmatic abilities and particularly with the processing of non-literal speech acts in which the listener has to identify the speaker's intention. The aim of this study was to test RHD subjects' ability to process non-literal speech acts. A chronometric approach to RHD and matched control performance showed that RHD subjects are impaired in the processing of non-literal speech, though they are also sensitive to the hierarchy of complexity among types. Only the processing of indirect speech acts was not shown to differ from that of normals, probably because the stimuli were of the conventional type. These results show the relevancy of a chronometric approach. They also emphasize the importance of further studying RHD subjects' ability to attribute intentions to protagonists in a short story.

Deficit of verb generation in nondemented patients with Parkinson's disease.

Clinical and neuroimaging studies have shown that verb processing suggests a preferential participation of a prefrontal network, which is dysfunctional in Parkinson's disease (PD). To assess a verb processing deficit in PD, we compared noun- and verb-generation tasks for 34 nondemented PD patients (according to the Dementia Rating Scale) with 34 matched normal subjects, using two intracategory tasks (noun/noun and verb/verb generation) and two intercategory tasks (noun/verb and verb/noun generation). PD patients were significantly impaired in the two tasks involving verb production, i.e., verb/verb and noun/verb generation, whereas their performance was similar to those of controls in the two tasks requiring noun production. For the two impaired tasks, we assessed 1) the influence of lexical competition that corresponds to the presence of several candidate words for a given stimulus; 2) the influence of slight cognitive dysfunction; and 3) the influence of motor deficit. Significant correlations were found between DRS scores and performance on the noun/verb task, and no significant correlations were found between lexical competition or motor deficit and performance. The specific deficit for verb production in PD patients is discussed in relation to deficits affecting either action or grammatical representations.

A relação pergunta-resposta como preditor do reconto de histórias / Question-asking organization

Esse estudo teve como objetivo verificar duas hipóteses da teoria de questionabilidade textual de Virbel: 1) o reconto é semelhante à organização de pergunta-resposta do autor; e, 2) a semelhança entre o reconto e força de questionabilidade da frase varia em função do grau de consistência do texto. Um primeiro comparou o reconto de 53 participantes com a força de questionabilidade das frases elementares do texto. Os resultados mostraram correlações significativas entre as duas variáveis de estudo. Um segundo experimento analisou o reconto de 141 participantes de 2 versões da história, que variaram quanto ao grau de consistência. Foram encontradas correlações significativas apenas na versão com maior grau de consistência. Os resultados dos 2 experimentos vão ao encontro da teoria de questionabilidade que propõe que para compreender e reconstruir uma história o ouvinte/leitor segue uma rede hierárquica que organiza as unidades significativas tendo por base a força de questionabilidade.

Ativaçäo de modelos mentais no recontar de histórias por idosos / Mental model activation in the recall of stories by older adults

Recontar histórias é uma atividade complexa que envolve recursos da memória de curta duraçäo (MCD) e da memória episódica (ME). Estratégias direcionadas a objetivos e intençöes particulares diminuem a sobrecarga da MCD e ativam a ME. Com o objetivo de estudar a influência do envelhecimento nestes mecanismos, estudamos o relato de uma história por dois grupos de adultos: 17 com 30 a 55 anos e 14 com mais de 60 anos. Os adultos mais jovens lembraram mais proposiçöes do que os idosos, mas ambos grupos relembraram melhor as macroestruturas do que as microestruturas e näo foi encontrada diferença no número de inferência, interferências e reconstruçöes. Entretanto, uma análise de ênfases dados à história, mostrou que jovens preferem relatar a seqüência de açöes e idosos, encadeam os fatos de forma subjetiva, sugerindo que, devido à uma reduçäo da memória de trabalho, utilizam-se mais das estratégias que recorrem às informaçöes armazenadas na memória episódica, deixando transparecer suas reprentaçöes mentais