Independence of first- and second-order memories in newborn rabbits.

WOS:000291649400006International audienceThe mammary pheromone promotes the acquisition of novel odorants (CS1) in newborn rabbits. Here, experiments pinpoint that CS1 becomes able to support neonatal learning of other odorants (CS2). We therefore evaluated whether these first- and second-order memories remained dependent after reactivation. Amnesia induced after CS2 recall selectively blocked this memory, when recall and amnesia of CS1 left the souvenir of CS2 safe; this finding partially differed from results obtained in adult mammals. Thus, in this model of neonatal appetitive odor learning, second-order memory seems to depend on first-order memory for its formation but not for its maintenance

Effets de l’expérience sur la perception de mélanges odorants chez l’Homme adulte et le lapereau nouveau-né

 Prix du meilleur poster• L’organisme est exposé à un environnement chimique complexe (mélanges d’odorants) duquel il doit extraire l’information.• Un signal véhiculé par un mélange peut être perçu de façon analytique AB = A+B et/ou synthétique AB = M (mélange)• Homme ->perception d’un mélange AB de façon partiellement synthétique (Le Berre et al.,2008)• Lapereaux -> perception du mélange AB de façon synthétique et analytique (Coureaud et al., 2008, 2009)Objectifs : Comment l’expérience influence-t-elle la perception de ce mélange AB et de ses composants A et B?Qu’en est-il pour un mélange perçu initialement de façon analytique (AC ou CD)

Perceptual processing strategy and exposure influence the perception of odor mixtures

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

When the nose must remain responsive: glutathione conjugation of the mammary pheromone in the newborn rabbit

In insects, xenobiotic-metabolizing enzymes were demonstrated to regulate pheromones inactivation, clearing them from the olfactory periphery and keeping receptors ready for stimulation renewal. Here, we investigate whether similar processes could occur in mammals, focusing on the pheromonal communication between female rabbits and their newborns. Lactating rabbits emit in their milk a volatile aldehyde, 2-methylbut-2-enal, that elicits searching-grasping in neonates; called the mammary pheromone (MP), it is critical for pups which are constrained to find nipples within the 5 min of daily nursing. For newborns, it is thus essential to remain sensitive to this odorant during the whole nursing period to display several actions of sucking. Here, we show that the MP is enzymatically conjugated to glutathione in newborn olfactory epithelium (OE), in accordance with the high mRNA expression of glutathione transferases evidenced by quantitative reverse transcription-PCR. This activity in the nose is higher than in the liver and in OE of newborns compared with weanlings (no more responsive to the pheromone). Therefore, the results pinpoint the existence of a high level of MP-glutathione conjugation activity in the OE of young rabbits, especially in the developmental window where the perceptual sensitivity toward the MP is crucial for survival

Le nez sous influence : une histoire animale

Organisateur : Loïc Briand (CSGA) ; évènement sous l'égide de la société des Neurosciencesabsen

Editorial: From Stimulus to Behavioral Decision-Making

International audienc

Pheromone-induced odour learning in newborn rabbits: action, development and adaptive function

Communication oraleInternational audienc

Activation cérébrale phéromone-induite ou olfacto-apprise chez le lapin nouveau-né

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Perception néonatale et mémoire de mélanges : des touts détectés tôt

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