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Boot E, Levy A, Gaeta G, Gunasekara N, Parkkinen E, Kontaris E, Jacquot M, Tachtsidis I. fNIRS a novel neuroimaging tool to investigate olfaction, olfactory imagery, and crossmodal interactions: a systematic review. Front Neurosci 2024; 18:1266664. [PMID: 38356646 PMCID: PMC10864673 DOI: 10.3389/fnins.2024.1266664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 01/02/2024] [Indexed: 02/16/2024] Open
Abstract
Olfaction is understudied in neuroimaging research compared to other senses, but there is growing evidence of its therapeutic benefits on mood and well-being. Olfactory imagery can provide similar health benefits as olfactory interventions. Harnessing crossmodal visual-olfactory interactions can facilitate olfactory imagery. Understanding and employing these cross-modal interactions between visual and olfactory stimuli could aid in the research and applications of olfaction and olfactory imagery interventions for health and wellbeing. This review examines current knowledge, debates, and research on olfaction, olfactive imagery, and crossmodal visual-olfactory integration. A total of 56 papers, identified using the PRISMA method, were evaluated to identify key brain regions, research themes and methods used to determine the suitability of fNIRS as a tool for studying these topics. The review identified fNIRS-compatible protocols and brain regions within the fNIRS recording depth of approximately 1.5 cm associated with olfactory imagery and crossmodal visual-olfactory integration. Commonly cited regions include the orbitofrontal cortex, inferior frontal gyrus and dorsolateral prefrontal cortex. The findings of this review indicate that fNIRS would be a suitable tool for research into these processes. Additionally, fNIRS suitability for use in naturalistic settings may lead to the development of new research approaches with greater ecological validity compared to existing neuroimaging techniques.
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Affiliation(s)
| | - Andrew Levy
- Metabolight Ltd., London, United Kingdom
- Wellcome Centre for Human Neuroimaging, University College, London, United Kingdom
| | - Giuliano Gaeta
- Health and Well-being Centre of Excellence, Givaudan UK Limited, Ashford, United Kingdom
| | - Natalie Gunasekara
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Emilia Parkkinen
- Health and Well-being Centre of Excellence, Givaudan UK Limited, Ashford, United Kingdom
| | - Emily Kontaris
- Health and Well-being Centre of Excellence, Givaudan UK Limited, Ashford, United Kingdom
| | - Muriel Jacquot
- Health and Well-being Centre of Excellence, Givaudan UK Limited, Ashford, United Kingdom
| | - Ilias Tachtsidis
- Metabolight Ltd., London, United Kingdom
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
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Puleo S, Braghieri A, Pacelli C, Bendini A, Toschi TG, Torri L, Piochi M, Di Monaco R. Food Neophobia, Odor and Taste Sensitivity, and Overall Flavor Perception in Food. Foods 2021; 10:foods10123122. [PMID: 34945673 PMCID: PMC8702209 DOI: 10.3390/foods10123122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 12/07/2021] [Accepted: 12/14/2021] [Indexed: 01/25/2023] Open
Abstract
Smell, which allows us to gather information about the hedonic value of an odor, is affected by many factors. This study aimed to assess the relationship among individual factors, odor sensitivity, and enjoyment, and to evaluate how overall flavor perception and liking in actual food samples are affected by odor sensitivity. A total of 749 subjects, from four different Italian regions, participated in the study. The olfactory capabilities test on four odors (anise, banana, mint, and pine), as well as PROP (6-n-prpyl-2-thiouracil) status and food neophobia were assessed. The subjects were clustered into three groups of odor sensitivity, based on the perceived intensity of anise. The liking and intensity of the overall flavor were evaluated for four chocolate puddings with increasing sweetness (C1, C2, C3, and C4). The individual variables significantly affected the perceived intensity and liking of the odors. Even if all of the odor sensitivity groups perceived the more intensely flavored samples as the C1 and C4 chocolate puddings, the high-sensitivity group scored the global flavor of all of the samples as more intense than the low-sensitivity group. The low-sensitive subjects evaluated the liking of the sweeter samples with higher scores than the moderate-sensitive subjects, whereas the high-sensitive subjects gave intermediate scores. In conclusion, odor sensitivity plays a pivotal role in the perception and liking of real food products; this has to be taken into account in the formulation of new products, suitable for particular categories with reduced olfactory abilities.
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Affiliation(s)
- Sharon Puleo
- Department of Agricultural Sciences, Food Science and Technology Division, University of Naples Federico II, 80055 Portici, Italy; (S.P.); (R.D.M.)
| | - Ada Braghieri
- School of Agricultural, Forestry, Food and Environmental Sciences, University of Basilicata, 85100 Potenza, Italy;
- Correspondence: ; Tel.: +39-0971-205101
| | - Corrado Pacelli
- School of Agricultural, Forestry, Food and Environmental Sciences, University of Basilicata, 85100 Potenza, Italy;
| | - Alessandra Bendini
- Department of Agricultural and Food Sciences (DiSTAL), University of Bologna, Piazza Goidanich 60, 47521 Cesena, Italy; (A.B.); (T.G.T.)
| | - Tullia Gallina Toschi
- Department of Agricultural and Food Sciences (DiSTAL), University of Bologna, Piazza Goidanich 60, 47521 Cesena, Italy; (A.B.); (T.G.T.)
| | - Luisa Torri
- Sensory and Consumer Science, University of Gastronomic Sciences, 12042 Pollenzo, Italy; (L.T.); (M.P.)
| | - Maria Piochi
- Sensory and Consumer Science, University of Gastronomic Sciences, 12042 Pollenzo, Italy; (L.T.); (M.P.)
| | - Rossella Di Monaco
- Department of Agricultural Sciences, Food Science and Technology Division, University of Naples Federico II, 80055 Portici, Italy; (S.P.); (R.D.M.)
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Niesen M, Trotta N, Noel A, Coolen T, Fayad G, Leurkin-Sterk G, Delpierre I, Henrard S, Sadeghi N, Goffard JC, Goldman S, De Tiège X. Structural and metabolic brain abnormalities in COVID-19 patients with sudden loss of smell. Eur J Nucl Med Mol Imaging 2021; 48:1890-1901. [PMID: 33398411 PMCID: PMC7781559 DOI: 10.1007/s00259-020-05154-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Accepted: 12/06/2020] [Indexed: 12/25/2022]
Abstract
OBJECTIVES Sudden loss of smell is a very common symptom of coronavirus disease 19 (COVID-19). This study characterizes the structural and metabolic cerebral correlates of dysosmia in patients with COVID-19. METHODS Structural brain magnetic resonance imaging (MRI) and positron emission tomography with [18F]-fluorodeoxyglucose (FDG-PET) were prospectively acquired simultaneously on a hybrid PET-MR in 12 patients (2 males, 10 females, mean age: 42.6 years, age range: 23-60 years) with sudden dysosmia and positive detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on nasopharyngeal swab specimens. FDG-PET data were analyzed using a voxel-based approach and compared with that of a group of healthy subjects. RESULTS Bilateral blocking of the olfactory cleft was observed in six patients, while subtle olfactory bulb asymmetry was found in three patients. No MRI signal abnormality downstream of the olfactory tract was observed. Decrease or increase in glucose metabolism abnormalities was observed (p < .001 uncorrected, k ≥ 50 voxels) in core olfactory and high-order neocortical areas. A modulation of regional cerebral glucose metabolism by the severity and the duration of COVID-19-related dysosmia was disclosed using correlation analyses. CONCLUSIONS This PET-MR study suggests that sudden loss of smell in COVID-19 is not related to central involvement due to SARS-CoV-2 neuroinvasiveness. Loss of smell is associated with subtle cerebral metabolic changes in core olfactory and high-order cortical areas likely related to combined processes of deafferentation and active functional reorganization secondary to the lack of olfactory stimulation.
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Affiliation(s)
- Maxime Niesen
- Department of Otorhinolaryngology, CUB Hôpital Erasme, Université libre de Bruxelles (ULB), Brussels, Belgium.
- Laboratoire de Cartographie fonctionnelle du Cerveau, UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium.
| | - Nicola Trotta
- Laboratoire de Cartographie fonctionnelle du Cerveau, UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium
- Department of Nuclear Medicine, CUB Hôpital Erasme, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - Antoine Noel
- Department of Otorhinolaryngology, CUB Hôpital Erasme, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - Tim Coolen
- Laboratoire de Cartographie fonctionnelle du Cerveau, UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium
- Department of Radiology, CUB Hôpital Erasme, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - Georges Fayad
- Department of Otorhinolaryngology, CUB Hôpital Erasme, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - Gil Leurkin-Sterk
- Laboratoire de Cartographie fonctionnelle du Cerveau, UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium
- Department of Nuclear Medicine, CUB Hôpital Erasme, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - Isabelle Delpierre
- Department of Radiology, CUB Hôpital Erasme, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - Sophie Henrard
- Laboratoire de Cartographie fonctionnelle du Cerveau, UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium
- Department of Internal Medicine, CUB Hôpital Erasme, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - Niloufar Sadeghi
- Department of Radiology, CUB Hôpital Erasme, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - Jean-Christophe Goffard
- Department of Internal Medicine, CUB Hôpital Erasme, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - Serge Goldman
- Laboratoire de Cartographie fonctionnelle du Cerveau, UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium
- Department of Nuclear Medicine, CUB Hôpital Erasme, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - Xavier De Tiège
- Laboratoire de Cartographie fonctionnelle du Cerveau, UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium
- Department of Nuclear Medicine, CUB Hôpital Erasme, Université libre de Bruxelles (ULB), Brussels, Belgium
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Speed LJ, Majid A. An Exception to Mental Simulation: No Evidence for Embodied Odor Language. Cogn Sci 2018; 42:1146-1178. [PMID: 29442364 PMCID: PMC6001635 DOI: 10.1111/cogs.12593] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 10/30/2017] [Accepted: 12/20/2017] [Indexed: 11/28/2022]
Abstract
Do we mentally simulate olfactory information? We investigated mental simulation of odors and sounds in two experiments. Participants retained a word while they smelled an odor or heard a sound, then rated odor/sound intensity and recalled the word. Later odor/sound recognition was also tested, and pleasantness and familiarity judgments were collected. Word recall was slower when the sound and sound‐word mismatched (e.g., bee sound with the word typhoon). Sound recognition was higher when sounds were paired with a match or near‐match word (e.g., bee sound with bee or buzzer). This indicates sound‐words are mentally simulated. However, using the same paradigm no memory effects were observed for odor. Instead it appears odor‐words only affect lexical‐semantic representations, demonstrated by higher ratings of odor intensity and pleasantness when an odor was paired with a match or near‐match word (e.g., peach odor with peach or mango). These results suggest fundamental differences in how odor and sound‐words are represented.
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Affiliation(s)
| | - Asifa Majid
- Centre for Language Studies, Radboud University.,Max Planck Institute for Psycholinguistics.,Donders Institute for Brain, Cognition and Behaviour, Radboud University
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Rezaei-Nodehi M, Shorofi SA, Bagheri-Nesami M, Ghafari R, Yazdani-Charati J, Darbeheshti M. The effect of pleasant olfactory mental imagery on the incidence and extent of atelectasis in patients after open heart surgery. Complement Ther Med 2017; 36:33-37. [PMID: 29458927 DOI: 10.1016/j.ctim.2017.11.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 05/10/2017] [Accepted: 11/21/2017] [Indexed: 10/18/2022] Open
Abstract
BACKGROUND AND PURPOSE Atelectasis is the most common pulmonary complication after open heart surgery. This study was intended to examine the effects of pleasant olfactory mental imagery on postoperative atelectasis in patients undergoing open heart surgery. MATERIALS AND METHODS This is a randomized controlled clinical trial. The sample consisted of 80 patients who were randomly assigned to either practice olfactory mental imagery (test group) or receive routine care (control group). A card with the image of roses was given to patients and they were asked to look at the image, visualize the scent of roses in the mind, and then sniff as much as possible, hold their breath for 2s and eventually exhale slowly through the nose. This procedure was consecutively repeated five times. After a fifteen-minute break, patients proceeded to practice olfactory mental imagery with other fruit images (banana, apple, and lemon). The test group executed the olfactory mental imagery for two hours in the morning and two hours in the afternoon on postoperative days 1 and 2. The control group received the routine ICU care. A questionnaire collected information on sociodemographic characteristics and clinical parameters. Chest radiographs were used to diagnose atelectasis, which were evaluated by the hospital radiologist. RESULTS No statistically significant differences were observed between the two groups regarding sociodemographic, medical and surgical information. The incidence of atelectasis in the test group (40%, n=16) was significantly lower than in the control group (67.5%, n=27) on postoperative day 2 (p=0.02). CONCLUSION Our findings suggest that olfactory mental imagery can improve respiratory function and reduce the risk of atelectasis in patients with cardiac surgery.
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Affiliation(s)
- Masoud Rezaei-Nodehi
- Student Research Committee, School of Nursing and Midwifery, Addiction Institute, Mazandaran University of Medical Sciences, Sari, Iran
| | - Seyed Afshin Shorofi
- Traditional and Complementary Medicine Research Center, Addiction Institute, Mazandaran University of Medical Sciences, Sari, Iran; Adjunct Research Fellow, Flinders University, Adelaide, Australia
| | - Masoumeh Bagheri-Nesami
- Traditional and Complementary Medicine Research Center, Addiction Institute, Mazandaran University of Medical Sciences, Sari, Iran.
| | - Rahman Ghafari
- Department of Cardiac Surgery, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
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Abstract
Qualitative-consciousness arises at the sensory level of olfactory processing and pervades our experience of smells to the extent that qualitative character is maintained whenever we are aware of undergoing an olfactory experience. Building upon the distinction between Access and Phenomenal Consciousness the paper offers a nuanced distinction between Awareness and Qualitative-consciousness that is applicable to olfaction in a manner that is conceptual precise and empirically viable. Mounting empirical research is offered substantiating the applicability of the distinction to olfaction and showing that olfactory qualitative-consciousness can occur without awareness, but any olfactory state that we are aware of being in is always qualitative. Evidence that olfactory sensory states have a qualitatively character in the absence of awareness derives from research on mate selection, the selection of social preference for social interaction and acquaintances, as well as the role of olfactory deficits in causing affective disorders. Furthermore, the conservation of secondary processing measures of olfactory valence during olfactory imagery experiments provides verification that olfactory awareness is always qualitatively conscious-all olfactory consciousness smells phenomenal.
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Affiliation(s)
- Benjamin D Young
- Department of Cognitive and Brain Science, Ben-Gurion University of the Negev Beer-Sheva, Israel
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Köster EP, van der Stelt O, Nixdorf RR, Linschoten MRI, de Wijk RA, Mojet J. Olfactory Imagination and Odor Processing: Three Same–Different Experiments. CHEMOSENS PERCEPT 2014. [DOI: 10.1007/s12078-014-9165-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Martínez NT. [Mental Imagery: Neurophysiology and Implications in Psychiatry]. ACTA ACUST UNITED AC 2014; 43:40-6. [PMID: 26573255 DOI: 10.1016/s0034-7450(14)70041-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 09/09/2013] [Indexed: 10/25/2022]
Abstract
OBJECTIVE To provide an explanation about what mental imagery is and some implications in psychiatry. METHODS This article is a narrative literature review. RESULTS There are many terms in which imagery representations are described in different fields of research. They are defined as perceptions in the absence of an external stimulus, and can be created in any sensory modality. Their neurophysiological substrate is almost the same as the one activated during sensory perception. There is no unified theory about its function, but it is possibly the way that our brain uses and manipulates the information to respond to the environment. CONCLUSIONS Mental imagery is an everyday phenomenon, and when it occurs in specific patterns it can be a sign of mental disorders.
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Affiliation(s)
- Nathalie Tamayo Martínez
- Especialista en Psiquiatría de Enlace, Maestría en Epidemiología Clínica, Pontificia Universidad Javeriana; Psiquiatra adscrita, Clínica Nuestra Señora de la Paz, Bogotá, Colombia.
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Sezille C, Fournel A, Rouby C, Rinck F, Bensafi M. Hedonic appreciation and verbal description of pleasant and unpleasant odors in untrained, trainee cooks, flavorists, and perfumers. Front Psychol 2014; 5:12. [PMID: 24478743 PMCID: PMC3900918 DOI: 10.3389/fpsyg.2014.00012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 01/07/2014] [Indexed: 11/24/2022] Open
Abstract
Olfaction is characterized by a salient hedonic dimension. Previous studies have shown that these affective responses to odors are modulated by physicochemical, physiological, and cognitive factors. The present study examined expertise influenced processing of pleasant and unpleasant odors on both perceptual and verbal levels. For this, performance on two olfactory tasks was compared between novices, trainee cooks, and experts (perfumers and flavorists): Members of all groups rated the intensity and pleasantness of pleasant and unpleasant odors (perceptual tasks). They were also asked to describe each of the 20 odorants as precisely as possible (verbal description task). On a perceptual level, results revealed that there were no group-related differences in hedonic ratings for unpleasant and pleasant odors. On a verbal level, descriptions of smells were richer (e.g., chemical, olfactory qualities, and olfactory sources terms) and did not refer to pleasantness in experts compared to untrained subjects who used terms referring to odor sources (e.g., candy) accompanied by terms referring to odor hedonics. In conclusion, the present study suggests that as novices, experts are able to perceptually discriminate odors on the basis of their pleasantness. However, on a semantic level, they conceptualize odors differently, being inclined to avoid any reference to odor hedonics.
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Affiliation(s)
- Caroline Sezille
- CNRS, UMR5292, INSERM1028, Lyon Neuroscience Research Center, University of Lyon Lyon, France
| | - Arnaud Fournel
- CNRS, UMR5292, INSERM1028, Lyon Neuroscience Research Center, University of Lyon Lyon, France
| | - Catherine Rouby
- CNRS, UMR5292, INSERM1028, Lyon Neuroscience Research Center, University of Lyon Lyon, France
| | - Fanny Rinck
- Lidilem Laboratory, University of Grenoble Grenoble, France
| | - Moustafa Bensafi
- CNRS, UMR5292, INSERM1028, Lyon Neuroscience Research Center, University of Lyon Lyon, France
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Palmiero M, Di Matteo R, Belardinelli MO. The representation of conceptual knowledge: visual, auditory, and olfactory imagery compared with semantic processing. Cogn Process 2013; 15:143-57. [PMID: 24337415 DOI: 10.1007/s10339-013-0586-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 10/11/2013] [Indexed: 11/24/2022]
Abstract
Two experiments comparing imaginative processing in different modalities and semantic processing were carried out to investigate the issue of whether conceptual knowledge can be represented in different format. Participants were asked to judge the similarity between visual images, auditory images, and olfactory images in the imaginative block, if two items belonged to the same category in the semantic block. Items were verbally cued in both experiments. The degree of similarity between the imaginative and semantic items was changed across experiments. Experiment 1 showed that the semantic processing was faster than the visual and the auditory imaginative processing, whereas no differentiation was possible between the semantic processing and the olfactory imaginative processing. Experiment 2 revealed that only the visual imaginative processing could be differentiated from the semantic processing in terms of accuracy. These results showed that the visual and auditory imaginative processing can be differentiated from the semantic processing, although both visual and auditory images strongly rely on semantic representations. On the contrary, no differentiation is possible within the olfactory domain. Results are discussed in the frame of the imagery debate.
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Affiliation(s)
- Massimiliano Palmiero
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy,
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Bensafi M. The Role of the Piriform Cortex in Human Olfactory Perception: Insights from Functional Neuroimaging Studies. CHEMOSENS PERCEPT 2011. [DOI: 10.1007/s12078-011-9110-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Poncelet J, Rinck F, Bourgeat F, Schaal B, Rouby C, Bensafi M, Hummel T. The effect of early experience on odor perception in humans: psychological and physiological correlates. Behav Brain Res 2009; 208:458-65. [PMID: 20035792 DOI: 10.1016/j.bbr.2009.12.011] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2009] [Revised: 12/09/2009] [Accepted: 12/14/2009] [Indexed: 11/13/2022]
Abstract
The olfactory function in humans is characterized by wide variability between individuals. One of the prominent factors that contribute to this plasticity is early exposure. The present study examined how brain activity is modulated by such olfactory experience. To this end, two groups of people living in France but originating from different cultures ("European-French" (EF, 18 subjects) vs. "Algerian-French" (AF, 19 subjects)) were tested, and their perceptual and physiological responses to the smells of mint (presumed to be experienced earlier in life by "Algerian-French" subjects) and of rose (control odorant) were compared. Neurophysiological responses were obtained in the form of chemosensory event-related potentials (CSERP). The results confirmed that the AF group was exposed to Mint tea earlier than the EF group. On the perceptual level, when asked to associate the smell of mint with objects or events retrieved from memory, the discourse of AF subjects included more "experience-oriented" associations than that of EF subjects. This was associated with longer P2 latency in CSERPs in response to the smell of mint in the AF group. These findings highlight the plasticity of behavioral and neural olfactory processes as a result of differential lifetime exposure.
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Affiliation(s)
- Johan Poncelet
- Laboratoire Neurosciences Sensorielles, Comportement, Cognition, Université de Lyon and CNRS UMR 5020, Lyon, France.
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Rouby C, Bourgeat F, Rinck F, Poncelet J, Bensafi M. Perceptual and sensorimotor differences between "good" and "poor" olfactory mental imagers. Ann N Y Acad Sci 2009; 1170:333-7. [PMID: 19686156 DOI: 10.1111/j.1749-6632.2009.03915.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Like odor perception, odor imagery is characterized by wide variability between individuals. The present two-part study sought to assess whether this inter-individual variability is underlain by behavioral differences in actual odor perception. In study 1, subjects judged the intensity, pleasantness, familiarity and edibility of 3 odorants. Participants were split into two olfactory imagery groups ("good" versus "poor" olfactory imagers) according to their scores on an imagery questionnaire. Results showed that good olfactory imagers judged all odors as more familiar and more edible than did poor olfactory imagers. Study 2 sought to determine whether these effects derived from a particular strategy of reenacting olfactomotor responses to smells on the part of good olfactory imagers, by recording their sniffs during odor perception. Results revealed that good olfactory imagers sniffed all odors longer and, again, judged these same odors as more edible and familiar. This supports the hypothesis of more complete odor processing and better access to odor semantics in good olfactory imagers.
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Affiliation(s)
- Catherine Rouby
- Université de Lyon, Université Claude Bernard Lyon1, CNRS UMR 5020 Neurosciences Sensorielles, Comportement, Cognition 69366 Lyon, France.
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