Molecular complexity determines the number of olfactory notes and the pleasantness of smells

One major unresolved problem in olfaction research is to relate the percept to the molecular structure of stimuli. The present study examined this issue and showed for the first time a quantitative structure-odor relationship in which the more structurally complex a monomolecular odorant, the more numerous the olfactory notes it evokes. Low-complexity odorants were also rated as more aversive, reflecting the fact that low molecular complexity may serve as a warning cue for the olfactory system. Taken together, these findings suggest that molecular complexity provides a framework to explain the subjective experience of smells

Semantic Knowledge Influences Prewired Hedonic Responses to Odors

Background Odor hedonic perception relies on decoding the physicochemical properties of odorant molecules and can be influenced in humans by semantic knowledge. The effect of semantic knowledge on such prewired hedonic processing over the life span has remained unclear. Methodology/Principal Findings The present study measured hedonic response to odors in different age groups (children, teenagers, young adults, and seniors) and found that children and seniors, two age groups characterized by either low level of (children) or weak access to (seniors) odor semantic knowledge, processed odor hedonics more on the basis of their physicochemical properties. In contrast, in teenagers and young adults, who show better levels of semantic odor representation, the role of physicochemical properties was less marked. Conclusions/Significance These findings demonstrate for the first time that the biological determinants that make an odor pleasant or unpleasant are more powerful at either end of the life span

The psychology of passion: A meta-analytical review of a decade of research on intrapersonal outcomes

It is just over a decade since Vallerand et al. (J Personal Soc Psychol 85:756–767, 2003) introduced the dualistic model of passion. In this study, we conduct a meta-analytical review of relationships between Vallerand et al’s two passions (viz. harmonious and obsessive), and intrapersonal outcomes, and test the moderating role of age, gender, domain, and culture. A systematic literature search yielded 94 studies, within which 27 criterion variables were reported. These criterion variables derived from four research areas within the intrapersonal sphere: (a) well-/ill-being, (b) motivation factors, (c) cognitive outcomes and, (d) behaviour and performance. From these areas we retrieved 1308 independent effect sizes and analysed them using random-effects models. Results showed harmonious passion positively corresponded with positive intrapersonal outcomes (e.g., positive affect, flow, performance). Obsessive passion, conversely, showed positive associations with positive and negative

Barriers to physical activity in coronary artery disease patients: Development and validation of a new scale

International audienceOBJECTIVE:To develop and validate a self-report questionnaire to measure barriers to regular physical activity (PA) in patients with stable coronary artery disease (CAD).METHODS:Phase 1: 17 patients completed a semi-structured interview. After grouping and reformulating the reported barriers, their pertinence was reevaluated by the patients. Then, a decision algorithm was used to select items. A principal component analysis was performed to determine content validity. Phase 2: 49 patients completed the questionnaire resulting from phase 1 twice, 7 days apart, and questionnaires to evaluate depression, anxiety, and the level of physical activity. Construct validity was evaluated by analysis of Spearman's correlation coefficient between the total score for the questionnaire and a convergent dimension (anxiety), as well as a divergent dimension (Dijon physical activity score). Internal consistency was evaluated by Cronbach's alpha coefficient. Test-retest reliability was evaluated by the intraclass coefficient (ICC).RESULTS:Eleven items were selected after phase 1. The questionnaire presented good face validity and the content validity seemed satisfactory after analysis of the literature by the experts. Construct validity was moderate. Internal consistency was very good (Cronbach's α>0.81). Reproducibility was excellent with an ICC at 0.95. Feasibility was good with less than 3minutes to complete the questionnaire.CONCLUSION:This questionnaire presents good psychometric properties. A further prospective study should evaluate sensitivity to change and help determine a threshold value indicating the need for a specific behavioral strategy to alleviate barriers to physical activity in these patient

A portable experimental apparatus for human olfactory fMRI experiments

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