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The aims of this study were to investigate semantic retrieval processes and errors across time during a semantic fluency task and to specify their components (i.e., executive vs. semantic). To do so, we analyzed the productions of 50 healthy participants (using the "supermarket" fluency task). The scores were compared before and after a 30-s interval. Across time, the results showed a decrease in the number of words produced and hard switching. Cluster switching and the number of intrusions remained constant, while clustering, and both the number of exemplars and repetitions increased. These results are discussed in terms of a progressive involvement of a semantic cognitive strategy of retrieval.

The aim of this study was to determine whether verbal knowledge can compensate for the age-related decline in word production during a fluency test. We assessed the performance of 20 young and 20 old subjects in standard letter and semantic fluency tasks over time (T1: 0-30 s vs. T2: 31-60 s). The number of words produced, switching, and clustering components (Troyer et al. Neuropsychology, 11(1): 138-146, 1997) were investigated. Correlations between age and cognitive factors (processing speed, executive functions, and vocabulary level) were analyzed. The results revealed a knowledge compensation mechanism in elderly subjects, but only in letter fluency productions. It only occurred during the second period and was related to an increase in the clustering component and a positive correlation between age and vocabulary level. The differences between letter and semantic fluency performances are discussed in terms of the nature of the nonsemantic and semantic components involved in these tasks.Keywords Aging Á Verbal fluency Á Clustering and switching across time It has often been stated in aging literature that old adults present some declines in cognitive functions. Particularly, numerous studies have demonstrated a reduction in the execution speed of cognitive operations and a deficit in the executive processes needed for temporary information storage and simultaneous performance of several tasks (Barringer et al

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Cet article concerne l’étude des phénomènes de compensation mnésique dans le cadre de la théorie des niveaux de traitement et du vieillissement. Précisément, l’objectif du travail était de déterminer la capacité du modèle MINERVA 2 à : 1. simuler les effets de profondeur de traitement et d’élaboration ainsi que leur interaction ; 2. prendre en compte les difficultés mnésiques liées à l’âge ; et 3. fournir une interprétation des phénomènes compensatoires cohérente avec celle proposée par Bäckman et Dixon (par ex., 1992). Une expérimentation nous a tout d’abord permis de retrouver les effets couramment observés dans la littérature du domaine. L’utilisation de MINERVA 2 nous a ensuite permis non seulement de simuler les résultats expérimentaux mais aussi d’en proposer un modèle explicatif proche de celui de Bäckman et Dixon, en regard de l’adéquation entre les caractéristiques du sujet et de la tâche, et du rôle de cette adéquation dans la mise en jeu des phénomènes compensatoires.