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Influential research has focused on identifying the common neural and behavioural substrates underlying episodic memory (the re-experiencing of specific details from past experiences) and spatial cognition, with some theories proposing that these are supported by the same mechanisms. However, the similarities and differences between these two forms of memory in humans require further specification. We used an individual-differences approach based on self-reported survey data collected in a large online study (n = 7,487), focusing on autobiographical episodic memory and spatial navigation and their relationship to object and spatial imagery abilities. Multivariate analyses replicated prior findings that autobiographical episodic memory abilities dissociated from spatial navigational abilities. Considering imagery, episodic autobiographical memory overlapped with imagery of objects, whereas spatial navigation overlapped with a tendency to focus on spatial schematics and manipulation. These results suggest that trait episodic autobiographical memory and spatial navigation correspond to distinct mental processes.

International audience; Multiblock component methods are applied to data sets for which several blocks of variables are measured on a same set of observations with the goal to analyze the relationships between these blocks of variables. In this article, we focus on multi-block component methods that integrate the information found in several blocks of explanatory variables in order to describe and explain one set of dependent variables. In the following, multiblock PLS and multiblock redundancy analysis are chosen, as particular cases of multiblock component methods when one set of variables is explained by a set of predictor variables that is organized into blocks. Because these multiblock techniques assume that the observations come from a homogeneous population they will provide suboptimal results when the observations actually come from different populations. A strategy to palliate this problem-presented in this article-is to use a technique such as clusterwise regression in order to identify homogeneous clusters of observations. This approach creates two new methods that provide clusters that have their own sets of regression coefficients. This combination of clustering and regres-B Stéphanie Bougeard 123 S. Bougeard et al. sion improves the overall quality of the prediction and facilitates the interpretation. In addition, the minimization of a well-defined criterion-by means of a sequential algorithm-ensures that the algorithm converges monotonously. Finally, the proposed method is distribution-free and can be used when the explanatory variables outnumber the observations within clusters. The proposed clusterwise multiblock methods are illustrated with of a simulation study and a (simulated) example from marketing.

International audience; Recently, several papers have investigated color-induced olfactory biases in wine tasting. In particular, Morrot et al. (Brain and Language, 79, 309–320, 2001) reported that visual information mostly drove wine description and that odor information was relatively unimportant in wine tasting. The present paper aims to study the relationship between the color of wine and its odor through a different approach. We hypothesize that people have stable mental representations of the aroma of the three wine color categories (red, white, and rosé) and that visual information is not a necessary clue to correctly categorize wines by color. In order to explore this issue, we adopted two complementary approaches. In the first one, we presented 18 wines (six reds, six whites, and six rosés) in dark glasses to our participants who were asked to smell the wines and categorize them into three categories: “red wine,” “white wine,” or “rosé wine.” Because we expected categorization performance to be affected by participants’ expertise, we used two groups of participants corresponding to wine experts and wine novices. The second approach was designed in order to verify whether the most salient perceptual differences among samples were correlated with the output of the ternary sorting task. Using the same 18 wines, we asked a third panel composed of trained assessors to perform a wine description, a free sorting task based on wines’ odor similarity, and finally, the same ternary sorting task carried out by experts and novices. We found that experts and novices were able to correctly identify red and white wines but not rosé wines. Contrary to our expectations, experts and novices performed at the same level. Trained panelists also categorized accurately white wines and red wines but not rosé wines. From a more perceptual point of view, the free sorting task yielded virtually the same result. Finally, in terms of wine description, again, a clear segmentation was obtained between white and red wines. White wines were described by yellow or orange odorant sources, while the red wines were described by dark odorant sources. In the light of our results, cognitive mechanisms potentially involved in the organization of sensory knowledge and wine categorization are also discussed.

What role categorization processes play in chemosensory expertise and its acquisition? In this paper, we address this question by exploring the criteria used by trained and untrained assessors when they categorize beers. Two experimental factors were manipulated: beer color and brewery. Participants sorted nine commercial beers coming in three different colors and from three different breweries. Participants sorted in two different conditions: in one condition, participants could see the beers, and in the other condition, they could not see the beers. We observed that in both tasting conditions (i.e., with or without vision), trained and untrained assessors categorized beers similarly. In the visual condition, assessors sorted beers by color, whereas in the blind condition, they sorted them by brewery. Overall, our results indicate that sensory training does not seem to have an effect on the criteria used to organize beer perceptions. This suggests that our trained beer assessors did not develop specific conceptual representations of beers during training. Moreover, it seems that when assessors categorize beers, they rely more on visual than on chemosensory information.

Multiple-set canonical correlation analysis (Generalized CANO or GCANO for short) is an important technique because it subsumes a number of interesting multivariate data analysis techniques as special cases. More recently, it has also been recognized as an important technique for integrating information from multiple sources. In this paper, we present a simple regularization technique for GCANO and demonstrate its usefulness. Regularization is deemed important as a way of supplementing insufficient data by prior knowledge, and/or of incorporating certain desirable properties in the estimates of parameters in the model. Implications of regularized GCANO for multiple correspondence analysis are also discussed. Examples are given to illustrate the use of the proposed technique.

This paper reviews processing of facial identity and expressions. The issue of independence of these two systems for these tasks has been addressed from different approaches over the past 25 years. More recently, neuroimaging techniques have provided researchers with new tools to investigate how facial information is processed in the brain. First, findings from "traditional" approaches to identity and expression processing are summarized. The review then covers findings from neuroimaging studies on face perception, recognition, and encoding. Processing of the basic facial expressions is detailed in light of behavioral and neuroimaging data. Whereas data from experimental and neuropsychological studies support the existence of two systems, the neuroimaging literature yields a less clear picture because it shows considerable overlap in activation patterns in response to the different face-processing tasks. Further, activation patterns in response to facial expressions support the notion of involved neural substrates for processing different facial expressions.

Nous avons conduit une experience afin d’etudier l’impact des formulations des enonces sur la resolution de problemes arithmetiques additifs chez des enfants de 6 a 10 ans. Trois variables ont ete controlees, toutes inter-sujets. Tous les problemes suivaient le meme patron sous-jacent — un etat initial (Ei), deux transformations (T1 et T2), un etat final (Ef) — mais l’inconnue etait tantot Ef (problemes S1) tantot Ei (S2). Les transformations etaient soit formulees en second (01) soit en premier (02). Enfin, la question se trouvait en position soit finale (Q1) soit initiale (Q2).