Vieillissement normal et cognition

Le vieillissement normal est accompagné de modifications du fonctionnement cognitif. Les plus fréquentes touchent la mémoire, l’attention ou les habiletés visuospatiales. Des facteurs généraux et des facteurs spécifiques expliquent ces changements indicateurs du vieillissement cérébral. Ils ne sont cependant pas obligatoires, mais dépendent des réserves en ressources cognitives que les individus possèdent, et de la façon dont ils continuent à les entretenir et à les exploiter. Le cerveau est en effet un organe qui s’adapte si on le met dans de bonnes conditions. Il est donc possible de retarder les effets du vieillissement et, dans certains cas, de les moduler.It is now well documented that normal aging modifies the cognitive functioning and most observations suggest that cognition evolves in the direction of deterioration. The more frequently impaired functions are memory, attention and visual-spatial abilities. On the other hand, some abilities seem to increase, such as vocabulary. Considering the aging effect on cognition, questions remain regarding directionality, universality and reversibility. A great variability in aged related impacts is observed among subjects and among cognitive domains. Some individuals evolved more rapidly than others. Some cognitive functions are more affected by aging than others. General and specific factors are hypothesized to explain the aged related cognitive decline. Among them, educational level, health, cognitive style, life style, personality, are likely to modulate the aged related cognitive evolution by influencing attentional resources and cerebral plasticity. Cognitive resources are essential to develop adaptative strategies. During the life span, resources are activated and increased by learning and training. Considering the role of cognitive resources, successful aging is dependent on several conditions : absence of disease leading to a loss of autonomy, maintenance of cognitive and physical activities, and active and social engaged lifestyle

Text comprehension in residual aphasia after basic-level linguistic recovery: a multiple case study

Aims: The primary objectives of this multiple case study were (1) to examine microstructure, macrostructure and situational model updating in text comprehension in five participants with left-brain damage (PWLBD), who continued to complain about problems with discourse comprehension without linguistic problems, and (2) to examine executive function and memory in these participants. Background: Text comprehension entails a complex interaction between cognitive and linguistic factors. In ageing, text comprehension depends on text characteristics, particularly semantic load. Persons with residual aphasia may complain of discourse comprehension difficulties without linguistic problems. Three levels of representation are involved in text comprehension (surface level, semantic level constituted by macrostructure and microstructure and situational level). Attention, verbal working memory, long-term memory and executive functions combine to allow processing of all levels of representation. Conclusions: These findings have two major implications. Analysing text comprehension using several texts with varying semantic loads is a promising tool for diagnosing residual aphasia and for designing specific cognitive interventions that target reading comprehension abilities in persons with residual aphasia. Methods & Procedures: Five PWLBD were selected for the study. We asked the participants to read and understand three narrative texts. The texts varied according to semantic load (the amount of information). In each text, we assessed macrostructure, microstructure and situational model updating. To evaluate memory and executive functions, we administered specific complementary tasks. Results were compared to normative data obtained from a previous study with a total of 60 neurologically intact control participants, divided into younger (N = 30) and older (N = 30) groups. Outcomes & Results: The results of the five PWLBD indicated that text comprehension is influenced by text characteristics, particularly semantic load; the findings demonstrated short-term memory and cognitive flexibility deficits. © 2014, Taylor & Francis

Clinical Focus on Prosodic, Discursive and Pragmatic Treatment for Right Hemisphere Damaged Adults: What's Right?

Researchers and clinicians acknowledge today that the contribution of both cerebral hemispheres is necessary to a full and adequate verbal communication. Indeed, it is estimated that at least 50% of right brain damaged individuals display impairments of prosodic, discourse, pragmatics and/or lexical semantics dimensions of communication. Since the 1990's, researchers have focused on the description and the assessment of these impairments and it is only recently that authors have shown interest in planning specific intervention approaches. However, therapists in rehabilitation settings still have very few available tools. This review of recent literature demonstrates that, even though theoretical knowledge needs further methodological investigation, intervention guidelines can be identified to target right hemisphere damage communication impairments in clinical practice. These principles can be incorporated by speech and language pathologists, in a structured intervention framework, aiming at fully addressing prosodic, discursive and pragmatic components of communication

Narrative discourse in young and older adults: behavioral and NIRS analyses

Discourse comprehension is at the core of communication capabilities, making it an important component of elderly populations' quality of life. The aim of this study is to evaluate changes in discourse comprehension and the underlying brain activity. Thirty-six participants read short stories and answered related probes in three conditions: micropropositions, macropropositions and situation models. Using near-infrared spectroscopy (NIRS), the variation in oxyhemoglobin (HbO2) and deoxyhemoglobin (HbR) concentrations was assessed throughout the task. The results revealed that the older adults performed with equivalent accuracy to the young ones at the macroproposition level of discourse comprehension, but were less accurate at the microproposition and situation model levels. Similar to what is described in the compensation-related utilization of neural circuits hypothesis (CRUNCH) model, older participants tended to have greater activation in the left dorsolateral prefrontal cortex while reading in all conditions. Although it did not enable them to perform similarly to younger participants in all conditions, this over-activation could be interpreted as a compensation mechanism

Brazilian Version of the Protocole Montréal d’Évaluation de la Communication (Protocole MEC): normative and reliability data

The lack of standardized instruments to evaluate communication disorders related to the right hemisphere was verified.A new evaluation tool was developed: Protocole Montréal d’Évaluation de la Communication – Protocole MEC, adapted to Brazilian Portuguese – Bateria Montreal de Avaliação da Comunicação – Bateria MAC (Montreal Evaluation of Communication Battery). The purpose was to present stratified normative data by age and educational level, and to verify the reliability parameters of the MEC Battery. 300 individuals, between the ages of 19 and 75 years, and levels of formal education between 2 and 35 years, participated in this study. They were divided equally into six normative groups, according to three age categories (young adults, intermediary age, and seniors) and two educational levels (low and high). Two procedures were used to check reliability: Cronbach alpha and reliability between evaluators. Results were established at the 10th percentile, and an alert point per task for each normative group. Cronbach’s alpha was, in general, between .70 and .90 and the average rate of agreement between evaluators varied from .62 to .94. Standards of age and education were established. The reliability of this instrument was verified. The psychometric legitimization of the MEC Battery will contribute to the diagnostic process for communicative disorders.Se verificó la falta de instrumentos estandarizados para evaluar los trastornos de comunicación relacionados con el hemisferio derecho. Se desarrolló una herramienta de evaluación nueva: el Protocole Montréal d’Évaluation de la Communication – ProtocoloMEC, adaptado al portugués brasileño – Bateria Montreal de Avaliação da Comunicação – Batería MAC (Batería de Evaluación de la Comunicación de Montreal). El objetivo fue presentar datos normativos estratificados por edad y nivel académico, y verificar los parámetros de fiabilidad de la batería MEC. 300 individuos, de edades entre los 19 y los 75 años y con 2 a 35 años de educación formal, participaron en este estudio. Se dividieron en seis grupos normativos, en función de tres categorías de edad (adultos jóvenes, edad mediana y mayores) y dos niveles educacionales (bajo y alto). Se emplearon dos procedimientos para confirmar la fiabilidad: alfa de Cronbach y fiabilidad inter-jueces. Se establecieron los resultados en el percentil 10 con un punto de alerta por tarea para cada grupo normativo. Los valores de alfa de Cronbach eran, en general, entre 0.70 y 0.90 y el grado de acuerdo entre los evaluadores variaba entre 0.62 y 0.94. Se establecieron normas de edad y educación. Se verificó la fiabilidad de este instrumento. La legitimación psicométrica de la Batería MEC contribuirá al proceso diagnóstico de los trastornos de comunicación

Effets de la formulation et du contenu d'une consigne sur l'exécution d'une tache présentée par ordinateur

Thèse de doctorat -- Université catholique de Louvain, 198

Quelques précisions sur l’entrevue clinique pour fin de diagnostic

Dans cet article, l’auteure soumet aux lecteurs quelques réflexions sur l’entrevue clinique. Un rappel de l’origine de la méthode est suivi de la présentation de quelques unes de ses caractéristiques. L’auteure y souligne la situation particulière des partenaires, les objectifs et le cheminement d’une telle entrevue. Elle aborde ensuite quelques problèmes méthodologiques concernant les questions de l’interviewer et les réponses de l’interviewé. Enfin, l’auteure présente quelques suggestions plus pratiques sur la façon de mener une entrevue diagnostique.In this paper the author presents some reflections on the clinical interview. A reference is made to the origin of this technique followed by a presentation of some of its characteristics. The author outlines the particular type of situation involved, the objectives, and the progress of such an interview. Some methodological problems concerning the interviewer's questions and the interviewee's responses are discussed. The paper concludes with some practical suggestions on how to direct a diagnostic interview.En este artículo, la autora présenta a los lectores algunas reflexiones sobre la entrevista clinica. Luego de recordar el origen del método, se presentan algunas de sus características. La autora recalca en el artículo la situación especial de los miembros, los objectivos y el desarrollo de tal entrevista. Enseguida enfoca algunos problemas metodológicos relativos a las preguntas del entrevistador y a las respuestas del entrevistado. Finalmente, la autora presenta algunas sugerencias prácticas sobre la forma de efectuar una entrevista de diagnóstico.In diesem Artikel legt die Verfasserin den Lesern einige Gedanken zur klinischen Befragung vor. Nach einem Hinweis auf den Ursprung der Methode stellt sie einige von deren typischen Eigenheiten dar. Die Verfasserin unterstreicht dabei die besondere Situation der Gesprächspartner, sowie die Ziele und den Ablauf einer solchen Befragung. Anschliessend behandelt sie einige methodologische Probleme bezüglich der Fragestellung und der erhaltenen Antworten. Die Verfasserin macht schliesslich einige praktischere Vorschläge über die Art, wie eine solche zur Diagnose (von Lernschwierigkeiten) unternommene Befragung durchzuführen sei

Trouble de dénomination lors du vieillissement normal

Ska Bernadette, Goulet Pierre. Trouble de dénomination lors du vieillissement normal. In: Langages, 24ᵉ année, n°96, 1989. De quelques aspects de la neurolinguistique en Amérique, sous la direction de Charles-Pierre Bouton, Jean-Luc Nespoulous et André Roch Lecours. pp. 112-127