L’agrément d’un vin dépend du jugement de ses qualités organoleptiques par un jury de professionnels. Les performances olfactives et gustatives nécessaires des dégustateurs y jouent un rôle déterminant. Pourtant jusqu’ici, ces aptitudes sensorielles fondamentales n'étaient pas directement prises en compte par les professionnels. Même si l’on peut donner une définition de l'expert, en préciser les capacités nécessaires, de multiples études ont mis en relief l’hétérogénéité des appréciations individuelles de dégustation et le manque de consensus forts. La littérature illustre les différences d’expertises entre professionnels et novices, mais aucune étude ne s’intéresse à l’amplitude des différences sensorielles interindividuelles chez les experts.Nos recherches nous ont conduit à caractériser les capacités olfactives de la population des professionnels du vin et à mesurer leur influence sur l’appréciation d’un vin. Nos mesures ont montré la variété interindividuelle des capacités perceptives, des appréciations hédoniques et des capacités cognitives recrutées par le traitement de l’information olfactive chez les professionnels du vin. Nos expériences ont suggéré que ces différences interindividuelles, relatives notamment à la sensibilité et l’appréciation hédonique, influencent la perception et le jugement d’un même vin par les experts. Cependant les résultats confirment aussi la possible influence de la dimension cognitive liée au vécu du sujet sur la perception olfactive plus ou moins complexe et l’apprentissage olfactif. Finalement, ce travail permet de déterminer des besoins en formation. Nous proposons en conséquence des outils pratiques d’évaluation des capacités sensorielles et des pédagogies d’entraînement adaptées. C'est l'occasion de souligner la pertinence de certains facteurs cognitifs dans l’amélioration des performances olfactives, tels que ceux impliquant l’attention ou l'imagerie mentale olfactives. / The quality of a wine is measured primarily by experts who evaluate its organoleptic features. Their olfactory and gustatory capacities are decisive, but these experts do not appreciate their own sensory abilities. Moreover, although we can give a clear definition of the expertise, several studies have shown that professionals are often confronted with disparities in their wine assessment. Several studies have also shown the differences between experts and novices, but no attention was paid to the diversity of the chemosensory abilities of the experts.At the Oenology Faculty in Bordeaux, with voluntary participation of the professionals, we characterized the olfactory performances of wine professionals and measured their impact on the wine assessment.The results showed significant inter-individual variation in olfactory sensitivities, hedonic ratings and cognitive abilities among the wine professionals. Further, our experiments have suggested that these inter-individual differences, especially concerning the sensitivity and the hedonic appreciation, influence perceptions and judgments of a same wine by the experts. However, the results confirm the possible influence of the cognitive dimensions related to the experience of the subject on their perception and their olfactory training. Finally, this work identifies training needs. We therefore propose and test practical tools for assessment of sensory performances and appropriate sensorial training. This has been an opportunity to highlight the potential role of attention or olfactory mental imagery in the improvement of the olfactory performance.

A great degree of interindividual variability has been established in measures of psychophysical olfactory performance and odor awareness in both children and adults. Previous studies have suggested the possibility that one of the factors that might contribute to this variability might be the degree of odor exposure in everyday contexts. In the present study, we hypothesized that children exposed to a greater variety of odors on a more frequent basis would exhibit higher odor identification and odor awareness scores. We have found an effect of odor exposure on the children's olfactory knowledge as reflected in their reports of olfactory behavior, but not olfactory abilities. In so doing, we replicated some of the previous findings in the literature of female over male advantage in the olfactory domain. Namely, we report that girls showed a more profound understanding of their olfactory environment and a greater degree of olfaction-oriented behavior, which was not accounted for by a gender difference in verbal fluency. Nevertheless, girls did not outperform boys on either of the measures of olfactory performance. Semi-longitudinal and longitudinal studies in verbally proficient children, employing both self- and parental reports of children's odor exposure and repeated olfactory testing, might...

Research suggests that olfactory perception of patients with schizophrenia differs from healthy people. In the context of previously conducted research, the present thesis addresses the differences in the abilities of identification and discrimination of odours and assessment of perceived odour qualities (pleasantness, familiarity, intensity, edibility) between patients with schizophrenia or acute and transient psychotic disorders and healthy volunteers, taking into account gender differences; in addition, the differences in the relationship between identification of odours and evaluation of the perceived qualities of odours between patients and healthy persons were explored as well as relationship between the severity of negative symptoms and olfactory perception. In line with other studies, deficits were found in patients in identification and discrimination of odours and in the assessment of odour familiarity compared to healthy subjects, with no gender differences. There were no differences in the relationship between the identification of odours and assessment of the perceived qualities of odours between patients and volunteers, and association of olfactory abilities and the assessment of perceived qualities of odours with the severity of negative symptoms was found only for identification of...

The main body of the thesis deals with selected factors underlying the considerable variability in human olfactory abilities and some odour awareness-related measures, addressed in samples ranging in age from middle childhood to young adulthood. The thesis consists of two parts. The first part (Chapter 1), first presents the major advances and developments that brought about something of a renaissance of scientific interest in the human sense of smell, including the recent proliferation of psychophysical studies, both basic research and clinical. Next, an outline of olfactory psychophysical measures and related olfactory abilities that are of relevance to the studies presented in this thesis is provided. Subsequently, the selected factors contributing to interindividual differences in olfactory abilities, that have been addressed by this thesis, are reviewed, namely the effect of sex (or gender), which is approached from a developmental perspective, childhood gender nonconformity, and personality. Finally, intraindividual fluctuations in olfactory performance are also mentioned in brief. Next, the focus shifts to odour awareness by first introducing the various approaches that can be adopted to get closer to the real-life context as opposed to laboratory setting (where most olfactory studies continue to be...

The main body of the thesis deals with selected factors underlying the considerable variability in human olfactory abilities and some odour awareness-related measures, addressed in samples ranging in age from middle childhood to young adulthood. The thesis consists of two parts. The first part (Chapter 1), first presents the major advances and developments that brought about something of a renaissance of scientific interest in the human sense of smell, including the recent proliferation of psychophysical studies, both basic research and clinical. Next, an outline of olfactory psychophysical measures and related olfactory abilities that are of relevance to the studies presented in this thesis is provided. Subsequently, the selected factors contributing to interindividual differences in olfactory abilities, that have been addressed by this thesis, are reviewed, namely the effect of sex (or gender), which is approached from a developmental perspective, childhood gender nonconformity, and personality. Finally, intraindividual fluctuations in olfactory performance are also mentioned in brief. Next, the focus shifts to odour awareness by first introducing the various approaches that can be adopted to get closer to the real-life context as opposed to laboratory setting (where most olfactory studies continue to be...