True and False Recognition Memories of Odors Induce Distinct Neural Signatures

Neural bases of human olfactory memory are poorly understood. Very few studies have examined neural substrates associated with correct odor recognition, and none has tackled neural networks associated with incorrect odor recognition. We investigated the neural basis of task performance during a yes–no odor recognition memory paradigm in young and elderly subjects using event-related functional magnetic resonance imaging. We explored four response categories: correct (Hit) and incorrect false alarm (FA) recognition, as well as correct (CR) and incorrect (Miss) rejection, and we characterized corresponding brain responses using multivariate analysis and linear regression analysis. We hypothesized that areas of the medial temporal lobe were differentially involved depending on the accuracy of odor recognition. In young adults, we found that significant activity in the hippocampus and the parahippocampal gyrus was associated with correct (true) recognition of odors, whereas the perirhinal cortex was associated with FAs and Misses. These findings are consistent with literature regarding hypothetical functional organization for memory processing. We also found that for correct recognition and rejection responses, the involvement of the hippocampus decreased when memory performances improved. In contrast to young individuals, elderly subjects were more prone to false memories and exhibited less specific activation patterns for the four response categories. Activation in the hippocampus and the parahippocampal gyrus was positively correlated with response bias scores for true and false recognition, demonstrating that conservative subjects produced an additional search effort leading to more activation of these two medial temporal lobe regions. These findings demonstrate that correct and incorrect recognition and rejection induce distinct neural signatures

Evidence for different patterns of chemosensory alterations in the elderly population: impact of age versus dependency

The present experiment aimed to explore the interindividual variability in chemosensory abilities among the elderly population. The chemosensory abilities of 559 subjects, aged from 65 to 99 years, were evaluated. Various categories of the elderly, including people who were living at home either without or with assistance, and people who were living in a nursing home, were interviewed. The results revealed that 43% of the sample presented well-preserved chemosensory abilities, whereas 21% of the participants presented a moderate impairment. Of the sample, 33% presented well-preserved olfactory abilities but strong impairment in gustatory abilities and 3% were nearly anosmic but remained able to perceive the salty taste, demonstrating that gustation and olfaction were not systematically damaged simultaneously. The results showed a link between the level of dependence (free living vs. living at home with help vs. nursing home) and chemosensory abilities, independently of the age effect. These results strengthen the hypothesis that the impairment of chemosensory abilities is not only an effect of age per se; rather, it is related to events that are associated with aging. Factors that lead to increased dependence (such as poor health) also lead to an impairment in chemosensory performance

Goût, préférences et comportement alimentaire

La population âgée se caractérise par une grande variabilité, que ce soit au niveau de la capacité à percevoir les saveurs et les arômes, des préférences alimentaires ou des attitudes vis-à-vis de l’alimentation. Cependant, nous avons montré que 88% des seniors jugeaient important d’avoir des aliments « savoureux, ayant un bon goût ». Nous avons également montré qu’améliorer la qualité sensorielle des aliments en fonction des recommandations des seniors eux-mêmes permettait d’augmenter les quantités consommées. Face à l’enjeu que représente la dénutrition chez les seniors, la recherche, les services de restauration et les industries agro-alimentaires se doivent de développer une offre alimentaire répondant aux besoins nutritionnels des seniors tout en maintenant leur plaisir à manger

The FORTIPHY project: Development of innovative food-based fortification solutions to sustain health in older people using co-creation approach

International audienc

Lutter contre la perte du plaisir de manger en gériatrie : les alternatives sensorielles

International audienc

Goût et préférences du consommateur âgé

RevueGoût et préférences du consommateur âgé. Journée de Printemp

Dénutrition chez les seniors : des repas mixés avec du goût: Publié sur lequotidien.lu/

Article publié sur lequotidien.lu.publié dans Le Quotidien [avec AFP (Agence France-Presse)], février 2015absen

Plaisir alimentaire : du souvenir à la consommation

National audienc

Je mange donc je suis... Mais de quoi je me souviens ? La mémoire sensorielle des aliments

conférence - débat dans le cadre du cycle de conférences "Détours en sciences".National audienceChoisir son menu devant un buffet de hors-d’œuvre, de plats, de desserts, quel dilemme ! C’est à la fois excitant (je peux choisir ce que je veux) et angoissant (mon choix sera-t-il le bon ?). Ce dilemme du choix, que l’on rencontre à une soirée, au restaurant, ou tout simplement chez soi en faisant le menu de la semaine, est en grande partie résolu grâce à notre mémoire : ce sont nos souvenirs qui vont guider nos choix. Notre mémoire "donne du sens" à l’information transmise par nos organes des sens : elle génère des attentes et permet la reconnaissance des aliments en rappelant les expériences antérieures. Je me souviens que cette andouillette était lourde à digérer, donc je préfère l’éviter. Je me souviens que cette madeleine trempée dans du thé avait un goût délicieux