Perceptual Processing Strategy and Exposure Influence the Perception of Odor Mixtures

Abstract

In flavor perception, both experience with the components of odor/taste mixtures and the cognitive strategy used to examine the interactions between the components influence the overall mixture perception. However, the effect of these factors on odor mixtures perception has never been studied. The present study aimed at evaluating whether 1) previous exposure to the odorants included in a mixture or 2) the synthetic or analytic strategy engaged during odorants mixture evaluation determines odor representation. Blending mixtures, in which subjects perceived a unique quality distinct from those of components, were chosen in order to induce a priori synthetic perception. In the first part, we checked whether the chosen mixtures presented blending properties for our subjects. In the second part, 3 groups of participants were either exposed to the odorants contributing to blending mixtures with a "pineapple" or a "red cordial" odor or nonexposed. In a following task, half of each group was assigned to a synthetic or an analytical task. The synthetic task consisted of rating how typical (i.e., representative) of the target odor name (pineapple or red cordial) were the mixtures and each of their components. The analytical task consisted of evaluating these stimuli on several scales labeled with the target odor name and odor descriptors of the components. Previous exposure to mixture components was found to decrease mixture typicality but only for the pineapple blending mixture. Likewise, subjects engaged in an analytical task rated both blending mixtures as less typical than did subjects engaged in a synthetic task. This study supports a conclusion that odor mixtures can be perceived either analytically or synthetically according to the cognitive strategy engaged.

Experience influences elemental and configural perception of certain binary odour mixtures in newborn rabbits

“…The results from the present study show that experience of a mixture or its components may rapidly affect the mode of perception in newborn rabbits, as previously shown in human adults (Stevenson, 2001;Le Berre et al, 2008;Le Berre et al, 2010). At least for certain mixtures, processing might operate on a continuum from strictly elemental to strictly configural perception: the initial perception of a mixture (free of any experience) would be located somewhere in between, depending on the mixture, whereas experience with either the mixture or the components would shift the perception to one or another mode.…”

“…The AB mixture included 0.3ϫ10 -5 and 0.7ϫ10 -5 gml -1 of components A and B, respectively; this 30/70 v/v ratio elicits the perception of a pineapple odour in human adults because of blending properties (ThomasDanguin et al, 2007;Le Berre et al, 2008;Le Berre et al, 2010;Barkat et al, 2011), and weak configural perception in newborn rabbits Coureaud et al, 2009;Coureaud et al, 2011). The AC mixture contained a 50/50 ratio of each component (0.5ϫ10 , a ratio chosen on the basis of a preliminary assay in humans).…”

“…In human adults, an AB mixture composed of ethyl isobutyrate (A) and ethyl maltol (B), smelling like strawberry and caramel, respectively, induces the configural perception of 'pineapple' (Le Barkat et al, 2011). Such a mixture has been called a blending mixture (Dreumont-Boudreau et al, 2006;Le Berre et al, 2008;Le Berre et al, 2010;Barkat et al, 2011). Recently, configural perception of the same AB mixture has also been reported in newborn rabbits: after a single conditioning to AB, pups respond to odorants A and B, showing abilities to extract the odour of each element during conditioning.…”

“…Gottlieb, 1983). Following a more or less intensive protocol, we exposed rabbit pups to the AB mixture cited above, initially perceived in a weak configural mode Coureaud et al, 2009;Coureaud et al, 2011;Le Berre et al, 2008;Le Berre et al, 2010;Barkat et al, 2011), or to one of its components, before testing their responsiveness to the mixture and to the single odorants. We hypothesized that variations in experience may modulate the perception of AB by neonates (Expt 1).…”

Chemical structure of odorants and perceptual similarity in ants

“…This model has found support for instance in humans (i.e. Le Berre et al, 2008a;Le Berre et al, 2008b). These theories are not mutually exclusive, and a combination is possible, where mixtures of two or more stimuli are represented by the individual elements (elemental theory), as well as an element unique to the mixture (configural theory): a mixture of AB will be perceived as ABC (e.g.…”