1
|
Okumura T, Kida I, Yokoi A, Nakai T, Nishimoto S, Touhara K, Okamoto M. Semantic context-dependent neural representations of odors in the human piriform cortex revealed by 7T MRI. Hum Brain Mapp 2024; 45:e26681. [PMID: 38656060 PMCID: PMC11041378 DOI: 10.1002/hbm.26681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 03/23/2024] [Accepted: 03/28/2024] [Indexed: 04/26/2024] Open
Abstract
Olfactory perception depends not only on olfactory inputs but also on semantic context. Although multi-voxel activity patterns of the piriform cortex, a part of the primary olfactory cortex, have been shown to represent odor perception, it remains unclear whether semantic contexts modulate odor representation in this region. Here, we investigated whether multi-voxel activity patterns in the piriform cortex change when semantic context modulates odor perception and, if so, whether the modulated areas communicate with brain regions involved in semantic and memory processing beyond the piriform cortex. We also explored regional differences within the piriform cortex, which are influenced by olfactory input and semantic context. We used 2 × 2 combinations of word labels and odorants that were perceived as congruent and measured piriform activity with a 1-mm isotropic resolution using 7T MRI. We found that identical odorants labeled with different words were perceived differently. This labeling effect was observed in multi-voxel activity patterns in the piriform cortex, as the searchlight decoding analysis distinguished identical odors with different labels for half of the examined stimulus pairs. Significant functional connectivity was observed between parts of the piriform cortex that were modulated by labels and regions associated with semantic and memory processing. While the piriform multi-voxel patterns evoked by different olfactory inputs were also distinguishable, the decoding accuracy was significant for only one stimulus pair, preventing definitive conclusions regarding the locational differences between areas influenced by word labels and olfactory inputs. These results suggest that multi-voxel patterns of piriform activity can be modulated by semantic context, possibly due to communication between the piriform cortex and the semantic and memory regions.
Collapse
Affiliation(s)
- Toshiki Okumura
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of TokyoTokyoJapan
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT)OsakaJapan
| | - Ikuhiro Kida
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT)OsakaJapan
- Graduate School of Frontier Biosciences, Osaka UniversityOsakaJapan
| | - Atsushi Yokoi
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT)OsakaJapan
- Graduate School of Frontier Biosciences, Osaka UniversityOsakaJapan
| | - Tomoya Nakai
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT)OsakaJapan
| | - Shinji Nishimoto
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT)OsakaJapan
- Graduate School of Frontier Biosciences, Osaka UniversityOsakaJapan
| | - Kazushige Touhara
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of TokyoTokyoJapan
- International Research Center for Neurointelligence (WPI‐IRCN), Institutes for Advanced Study, The University of TokyoTokyoJapan
| | - Masako Okamoto
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of TokyoTokyoJapan
| |
Collapse
|
2
|
Mignot C, Weise S, Podlesek D, Leonhardt G, Bensafi M, Hummel T. What do brain oscillations tell about the human sense of smell? J Neurosci Res 2024; 102:e25335. [PMID: 38634155 DOI: 10.1002/jnr.25335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 04/04/2024] [Accepted: 04/06/2024] [Indexed: 04/19/2024]
Abstract
Brain activity may manifest itself as oscillations which are repetitive rhythms of neuronal firing. These local field potentials can be measured via intracranial electroencephalography (iEEG). This review focuses on iEEG used to map human brain structures involved in olfaction. After presenting the methodology of the review, a summary of the brain structures involved in olfaction is given, followed by a review of the literature on human olfactory oscillations in different contexts. A single case is provided as an illustration of the olfactory oscillations. Overall, the timing and sequence of oscillations found in the different structures of the olfactory system seem to play an important role for olfactory perception.
Collapse
Affiliation(s)
- Coralie Mignot
- Smell & Taste Clinic, Department of Otorhinolaryngology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Susanne Weise
- Smell & Taste Clinic, Department of Otorhinolaryngology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Dino Podlesek
- Department of Neurosurgery, Technische Universität Dresden, Dresden, Germany
| | - Georg Leonhardt
- Department of Neurosurgery, Technische Universität Dresden, Dresden, Germany
| | - Moustafa Bensafi
- Lyon Neuroscience Research Center, CNRS-INSERM-University Claude Bernard of Lyon, CH Le Vinatier, Lyon, France
| | - Thomas Hummel
- Smell & Taste Clinic, Department of Otorhinolaryngology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| |
Collapse
|
3
|
Ye Y, Wang Y, Zhuang Y, Tan H, Zuo Z, Yun H, Yuan K, Zhou W. Decomposition of an odorant in olfactory perception and neural representation. Nat Hum Behav 2024:10.1038/s41562-024-01849-0. [PMID: 38499771 DOI: 10.1038/s41562-024-01849-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Accepted: 02/19/2024] [Indexed: 03/20/2024]
Abstract
Molecules-the elementary units of substances-are commonly considered the units of processing in olfactory perception, giving rise to undifferentiated odour objects invariant to environmental variations. By selectively perturbing the processing of chemical substructures with adaptation ('the psychologist's microelectrode') in a series of psychophysical and neuroimaging experiments (458 participants), we show that two perceptually distinct odorants sharing part of their structural features become significantly less discernible following adaptation to a third odorant containing their non-shared structural features, in manners independent of olfactory intensity, valence, quality or general olfactory adaptation. The effect is accompanied by reorganizations of ensemble activity patterns in the posterior piriform cortex that parallel subjective odour quality changes, in addition to substructure-based neural adaptations in the anterior piriform cortex and amygdala. Central representations of odour quality and the perceptual outcome thus embed submolecular structural information and are malleable by recent olfactory encounters.
Collapse
Affiliation(s)
- Yuting Ye
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
- Institute of Psychology, School of Public Affairs, Xiamen University, Xiamen, China
| | - Yanqing Wang
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
- School of Psychology, Northwest Normal University, Lanzhou, China
| | - Yuan Zhuang
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Huibang Tan
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Zhentao Zuo
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, China
- Sino-Dannish College, University of Chinese Academy of Sciences, Beijing, China
| | - Hanqi Yun
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Kaiqi Yuan
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Wen Zhou
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China.
- Chinese Institute for Brain Research, Beijing, China.
| |
Collapse
|
4
|
Liu D, Lu J, Wei L, Yao M, Yang H, Lv P, Wang H, Zhu Y, Zhu Z, Zhang X, Chen J, Yang QX, Zhang B. Olfactory deficit: a potential functional marker across the Alzheimer's disease continuum. Front Neurosci 2024; 18:1309482. [PMID: 38435057 PMCID: PMC10907997 DOI: 10.3389/fnins.2024.1309482] [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: 10/08/2023] [Accepted: 02/02/2024] [Indexed: 03/05/2024] Open
Abstract
Alzheimer's disease (AD) is a prevalent form of dementia that affects an estimated 32 million individuals globally. Identifying early indicators is vital for screening at-risk populations and implementing timely interventions. At present, there is an urgent need for early and sensitive biomarkers to screen individuals at risk of AD. Among all sensory biomarkers, olfaction is currently one of the most promising indicators for AD. Olfactory dysfunction signifies a decline in the ability to detect, identify, or remember odors. Within the spectrum of AD, impairment in olfactory identification precedes detectable cognitive impairments, including mild cognitive impairment (MCI) and even the stage of subjective cognitive decline (SCD), by several years. Olfactory impairment is closely linked to the clinical symptoms and neuropathological biomarkers of AD, accompanied by significant structural and functional abnormalities in the brain. Olfactory behavior examination can subjectively evaluate the abilities of olfactory identification, threshold, and discrimination. Olfactory functional magnetic resonance imaging (fMRI) can provide a relatively objective assessment of olfactory capabilities, with the potential to become a promising tool for exploring the neural mechanisms of olfactory damage in AD. Here, we provide a timely review of recent literature on the characteristics, neuropathology, and examination of olfactory dysfunction in the AD continuum. We focus on the early changes in olfactory indicators detected by behavioral and fMRI assessments and discuss the potential of these techniques in MCI and preclinical AD. Despite the challenges and limitations of existing research, olfactory dysfunction has demonstrated its value in assessing neurodegenerative diseases and may serve as an early indicator of AD in the future.
Collapse
Affiliation(s)
- Dongming Liu
- Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Institute of Medical Imaging and Artificial Intelligence, Nanjing University, Nanjing, China
- Medical Imaging Center, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China
| | - Jiaming Lu
- Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Institute of Medical Imaging and Artificial Intelligence, Nanjing University, Nanjing, China
- Medical Imaging Center, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China
| | - Liangpeng Wei
- Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Institute of Medical Imaging and Artificial Intelligence, Nanjing University, Nanjing, China
- Medical Imaging Center, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China
| | - Mei Yao
- Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Institute of Medical Imaging and Artificial Intelligence, Nanjing University, Nanjing, China
- Medical Imaging Center, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China
| | - Huiquan Yang
- Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Institute of Medical Imaging and Artificial Intelligence, Nanjing University, Nanjing, China
- Medical Imaging Center, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China
| | - Pin Lv
- Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Institute of Medical Imaging and Artificial Intelligence, Nanjing University, Nanjing, China
- Medical Imaging Center, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China
| | - Haoyao Wang
- Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Institute of Medical Imaging and Artificial Intelligence, Nanjing University, Nanjing, China
- Medical Imaging Center, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China
| | - Yajing Zhu
- Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Zhengyang Zhu
- Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Xin Zhang
- Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Institute of Medical Imaging and Artificial Intelligence, Nanjing University, Nanjing, China
- Medical Imaging Center, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China
| | - Jiu Chen
- Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Institute of Medical Imaging and Artificial Intelligence, Nanjing University, Nanjing, China
- Medical Imaging Center, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China
| | - Qing X. Yang
- Department of Radiology, Center for NMR Research, Penn State University College of Medicine, Hershey, PA, United States
| | - Bing Zhang
- Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Institute of Medical Imaging and Artificial Intelligence, Nanjing University, Nanjing, China
- Medical Imaging Center, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, China
- Jiangsu Key Laboratory of Molecular Medicine, Nanjing, China
- Institute of Brain Science, Nanjing University, Nanjing, China
- Jiangsu Provincial Medical Key Discipline (Laboratory), Nanjing, China
| |
Collapse
|
5
|
Terral G, Harrell E, Lepousez G, Wards Y, Huang D, Dolique T, Casali G, Nissant A, Lledo PM, Ferreira G, Marsicano G, Roux L. Endogenous cannabinoids in the piriform cortex tune olfactory perception. Nat Commun 2024; 15:1230. [PMID: 38336844 PMCID: PMC10858223 DOI: 10.1038/s41467-024-45161-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 01/17/2024] [Indexed: 02/12/2024] Open
Abstract
Sensory perception depends on interactions between external inputs transduced by peripheral sensory organs and internal network dynamics generated by central neuronal circuits. In the sensory cortex, desynchronized network states associate with high signal-to-noise ratio stimulus-evoked responses and heightened perception. Cannabinoid-type-1-receptors (CB1Rs) - which influence network coordination in the hippocampus - are present in anterior piriform cortex (aPC), a sensory paleocortex supporting olfactory perception. Yet, how CB1Rs shape aPC network activity and affect odor perception is unknown. Using pharmacological manipulations coupled with multi-electrode recordings or fiber photometry in the aPC of freely moving male mice, we show that systemic CB1R blockade as well as local drug infusion increases the amplitude of gamma oscillations in aPC, while simultaneously reducing the occurrence of synchronized population events involving aPC excitatory neurons. In animals exposed to odor sources, blockade of CB1Rs reduces correlation among aPC excitatory units and lowers behavioral olfactory detection thresholds. These results suggest that endogenous endocannabinoid signaling promotes synchronized population events and dampen gamma oscillations in the aPC which results in a reduced sensitivity to external sensory inputs.
Collapse
Affiliation(s)
- Geoffrey Terral
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France
- Univ. Bordeaux, INSERM, Neurocentre Magendie, U1215, F-33000, Bordeaux, France
| | - Evan Harrell
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France
| | - Gabriel Lepousez
- Perception and Memory Unit, CNRS, Joint Research Unit 3571, Université Paris Cité, Institut Pasteur, 75015, Paris, France
| | - Yohan Wards
- Univ. Bordeaux, INSERM, Neurocentre Magendie, U1215, F-33000, Bordeaux, France
| | - Dinghuang Huang
- Univ. Bordeaux, INSERM, Neurocentre Magendie, U1215, F-33000, Bordeaux, France
| | | | - Giulio Casali
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France
| | - Antoine Nissant
- Perception and Memory Unit, CNRS, Joint Research Unit 3571, Université Paris Cité, Institut Pasteur, 75015, Paris, France
| | - Pierre-Marie Lledo
- Perception and Memory Unit, CNRS, Joint Research Unit 3571, Université Paris Cité, Institut Pasteur, 75015, Paris, France
| | - Guillaume Ferreira
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeurO, UMR 1286, F-33000, Bordeaux, France
| | - Giovanni Marsicano
- Univ. Bordeaux, INSERM, Neurocentre Magendie, U1215, F-33000, Bordeaux, France
| | - Lisa Roux
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France.
| |
Collapse
|
6
|
Abstract
Historically, the human sense of smell has been regarded as the odd stepchild of the senses, especially compared to the sensory bravado of seeing, touching, and hearing. The idea that the human olfaction has little to contribute to our experience of the world is commonplace, though with the emergence of COVID-19 there has rather been a sea change in this understanding. An ever increasing body of work has convincingly highlighted the keen capabilities of the human nose and the sophistication of the human olfactory system. Here, we provide a concise overview of the neuroscience of human olfaction spanning the last 10-15 years, with focus on the peripheral and central mechanisms that underlie how odor information is processed, packaged, parceled, predicted, and perturbed to serve odor-guided behaviors. We conclude by offering some guideposts for harnessing the next decade of olfactory research in all its shapes and forms.
Collapse
Affiliation(s)
| | - Jay A Gottfried
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA; ,
- Department of Psychology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| |
Collapse
|
7
|
Perszyk EE, Davis XS, Djordjevic J, Jones-Gotman M, Trinh J, Hutelin Z, Veldhuizen MG, Koban L, Wager TD, Kober H, Small DM. Odour-imagery ability is linked to food craving, intake, and adiposity change in humans. Nat Metab 2023; 5:1483-1493. [PMID: 37640944 DOI: 10.1038/s42255-023-00874-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 07/25/2023] [Indexed: 08/31/2023]
Abstract
It is well-known that food-cue reactivity (FCR) is positively associated with body mass index (BMI)1 and weight change2, but the mechanisms underlying these relationships are incompletely understood. One prominent theory of craving posits that the elaboration of a desired substance through sensory imagery intensifies cravings, thereby promoting consumption3. Olfaction is integral to food perception, yet the ability to imagine odours varies widely4. Here we test in a basic observational study whether this large variation in olfactory imagery drives FCR strength to promote adiposity in 45 adults (23 male). We define odour-imagery ability as the extent to which imagining an odour interferes with the detection of a weak incongruent odour (the 'interference effect'5). As predicted in our preregistration, the interference effect correlates with the neural decoding of imagined, but not real, odours. These perceptual and neural measures of odour imagery are in turn associated with FCR, defined by the rated craving intensity of liked foods and cue-potentiated intake. Finally, odour imagery exerts positive indirect effects on changes in BMI and body-fat percentage over one year via its influences on FCR. These findings establish odour imagery as a driver of FCR that in turn confers risk for weight gain.
Collapse
Affiliation(s)
- Emily E Perszyk
- Modern Diet and Physiology Research Center, New Haven, CT, USA.
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA.
| | - Xue S Davis
- Modern Diet and Physiology Research Center, New Haven, CT, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Jelena Djordjevic
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Marilyn Jones-Gotman
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Jessica Trinh
- Modern Diet and Physiology Research Center, New Haven, CT, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Zach Hutelin
- Modern Diet and Physiology Research Center, New Haven, CT, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Maria G Veldhuizen
- Department of Anatomy, Faculty of Medicine, Mersin University, Ciftlikkoy Campus, Mersin, Turkey
| | - Leonie Koban
- Lyon Neuroscience Research Center (CRNL), CNRS, INSERM, University Claude Bernard Lyon 1, Bron, France
| | - Tor D Wager
- Department of Psychological and Brain Sciences, Dartmouth College, Hanover, NH, USA
| | - Hedy Kober
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Department of Psychology, Yale University, New Haven, CT, USA
| | - Dana M Small
- Modern Diet and Physiology Research Center, New Haven, CT, USA.
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA.
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada.
- Department of Psychology, Yale University, New Haven, CT, USA.
- Department of Medicine, McGill University Health Center, Montreal, Quebec, Canada.
| |
Collapse
|
8
|
Sagar V, Shanahan LK, Zelano CM, Gottfried JA, Kahnt T. High-precision mapping reveals the structure of odor coding in the human brain. Nat Neurosci 2023; 26:1595-1602. [PMID: 37620443 PMCID: PMC10726579 DOI: 10.1038/s41593-023-01414-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 07/18/2023] [Indexed: 08/26/2023]
Abstract
Odor perception is inherently subjective. Previous work has shown that odorous molecules evoke distributed activity patterns in olfactory cortices, but how these patterns map on to subjective odor percepts remains unclear. In the present study, we collected neuroimaging responses to 160 odors from 3 individual subjects (18 h per subject) to probe the neural coding scheme underlying idiosyncratic odor perception. We found that activity in the orbitofrontal cortex (OFC) represents the fine-grained perceptual identity of odors over and above coarsely defined percepts, whereas this difference is less pronounced in the piriform cortex (PirC) and amygdala. Furthermore, the implementation of perceptual encoding models enabled us to predict olfactory functional magnetic resonance imaging responses to new odors, revealing that the dimensionality of the encoded perceptual spaces increases from the PirC to the OFC. Whereas encoding of lower-order dimensions generalizes across subjects, encoding of higher-order dimensions is idiosyncratic. These results provide new insights into cortical mechanisms of odor coding and suggest that subjective olfactory percepts reside in the OFC.
Collapse
Affiliation(s)
- Vivek Sagar
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | | | - Christina M Zelano
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Jay A Gottfried
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
- Department of Psychology, University of Pennsylvania, Philadelphia, PA, USA
| | - Thorsten Kahnt
- National Institute on Drug Abuse Intramural Research Program, Baltimore, MD, USA.
| |
Collapse
|
9
|
Ekanayake A, Yang Q, Kanekar S, Ahmed B, McCaslin S, Kalra D, Eslinger P, Karunanayaka P. Monorhinal and Birhinal Odor Processing in Humans: an fMRI investigation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.01.551475. [PMID: 37577649 PMCID: PMC10418263 DOI: 10.1101/2023.08.01.551475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
The olfactory nerve, also known as cranial nerve I, is known to have exclusive ipsilateral projections to primary olfactory cortical structures. It is still unclear whether these projections also correspond to functional pathways of odor processing. In an olfactory functional magnetic resonance imaging (fMRI) study of twenty young healthy subjects with a normal sense of smell, we tested whether nostril specific stimulation with phenyl ethyl alcohol (PEA), a pure olfactory stimulant, asymmetrically activates primary or secondary olfactory-related brain structures such as primary olfactory cortex, entorhinal cortex, and orbitofrontal cortex. The results indicated that without a challenging olfactory task, passive (no sniffing) and active (with sniffing) nostril-specific PEA stimulation did not produce asymmetrical fMRI activation in olfactory cortical structures.
Collapse
Affiliation(s)
- Anupa Ekanayake
- Grodno State Medical University, Grodno, Belarus
- Department of Radiology, Penn State University College of Medicine, Hershey, PA, USA
| | - Qing Yang
- Department of Radiology, Penn State University College of Medicine, Hershey, PA, USA
- Department of Neurosurgery, Penn State University College of Medicine, Hershey, PA, USA
| | - Sangam Kanekar
- Department of Radiology, Penn State University College of Medicine, Hershey, PA, USA
| | - Biyar Ahmed
- Department of Radiology, Penn State University College of Medicine, Hershey, PA, USA
| | - Silas McCaslin
- Department of Radiology, Penn State University College of Medicine, Hershey, PA, USA
| | - Deepak Kalra
- Department of Neurology, Penn State University College of Medicine, Hershey, PA, USA
| | - Paul Eslinger
- Department of Radiology, Penn State University College of Medicine, Hershey, PA, USA
- Department of Neurology, Penn State University College of Medicine, Hershey, PA, USA
| | - Prasanna Karunanayaka
- Department of Radiology, Penn State University College of Medicine, Hershey, PA, USA
| |
Collapse
|
10
|
Auguste A, Fourcaud-Trocmé N, Meunier D, Gros A, Garcia S, Messaoudi B, Thevenet M, Ravel N, Veyrac A. Distinct brain networks for remote episodic memory depending on content and emotional experience. Prog Neurobiol 2023; 223:102422. [PMID: 36796748 DOI: 10.1016/j.pneurobio.2023.102422] [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: 10/18/2022] [Revised: 01/19/2023] [Accepted: 02/13/2023] [Indexed: 02/17/2023]
Abstract
Memories of life episodes are the heart of individual stories. However, modelling episodic memory is a major challenge in both humans and animals when considering all its characteristics. As a consequence, the mechanisms that underlie the storage of old nontraumatic episodic memories remain enigmatic. Here, using a new task in rodents that models human episodic memory including odour/place/context components and applying advances behavioural and computational analyses, we show that rats form and recollect integrated remote episodic memories of two occasionally encountered complex episodes occurring in their daily life. Similar to humans, the information content and accuracy of memories vary across individuals and depend on the emotional relationship with odours experienced during the very first episode. We used cellular brain imaging and functional connectivity analyses, to find out the engrams of remote episodic memories for the first time. Activated brain networks completely reflect the nature and content of episodic memories, with a larger cortico-hippocampal network when the recollection is complete and with an emotional brain network related to odours that is critical in maintaining accurate and vivid memories. The engrams of remote episodic memories remain highly dynamic since synaptic plasticity processes occur during recall related to memory updates and reinforcement.
Collapse
Affiliation(s)
- Anne Auguste
- UMR 5292 CNRS, INSERM U1028, University Lyon1, Olfaction: From coding to Memory Team, Lyon Neuroscience Research Center, F-69366 Lyon, France
| | - Nicolas Fourcaud-Trocmé
- UMR 5292 CNRS, INSERM U1028, University Lyon1, Olfaction: From coding to Memory Team, Lyon Neuroscience Research Center, F-69366 Lyon, France
| | - David Meunier
- University Aix Marseille, Insitut des Neurosciences de la Timone, Marseille, France
| | - Alexandra Gros
- UMR 5292 CNRS, INSERM U1028, University Lyon1, Olfaction: From coding to Memory Team, Lyon Neuroscience Research Center, F-69366 Lyon, France
| | - Samuel Garcia
- UMR 5292 CNRS, INSERM U1028, University Lyon1, Olfaction: From coding to Memory Team, Lyon Neuroscience Research Center, F-69366 Lyon, France
| | - Belkacem Messaoudi
- UMR 5292 CNRS, INSERM U1028, University Lyon1, Olfaction: From coding to Memory Team, Lyon Neuroscience Research Center, F-69366 Lyon, France
| | - Marc Thevenet
- UMR 5292 CNRS, INSERM U1028, University Lyon1, Olfaction: From coding to Memory Team, Lyon Neuroscience Research Center, F-69366 Lyon, France
| | - Nadine Ravel
- UMR 5292 CNRS, INSERM U1028, University Lyon1, Olfaction: From coding to Memory Team, Lyon Neuroscience Research Center, F-69366 Lyon, France
| | - Alexandra Veyrac
- UMR 5292 CNRS, INSERM U1028, University Lyon1, Olfaction: From coding to Memory Team, Lyon Neuroscience Research Center, F-69366 Lyon, France.
| |
Collapse
|
11
|
Perszyk EE, Davis XS, Djordjevic J, Jones-Gotman M, Trinh J, Hutelin Z, Veldhuizen MG, Koban L, Wager TD, Kober H, Small DM. Odor imagery but not perception drives risk for food cue reactivity and increased adiposity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.06.527292. [PMID: 36798231 PMCID: PMC9934556 DOI: 10.1101/2023.02.06.527292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Mental imagery has been proposed to play a critical role in the amplification of cravings. Here we tested whether olfactory imagery drives food cue reactivity strength to promote adiposity in 45 healthy individuals. We measured odor perception, odor imagery ability, and food cue reactivity using self-report, perceptual testing, and neuroimaging. Adiposity was assessed at baseline and one year later. Brain responses to real and imagined odors were analyzed with univariate and multivariate decoding methods to identify pattern-based olfactory codes. We found that the accuracy of decoding imagined, but not real, odor quality correlated with a perceptual measure of odor imagery ability and with greater adiposity changes. This latter relationship was mediated by cue-potentiated craving and intake. Collectively, these findings establish odor imagery ability as a risk factor for weight gain and more specifically as a mechanism by which exposure to food cues promotes craving and overeating.
Collapse
Affiliation(s)
- Emily E. Perszyk
- Modern Diet and Physiology Research Center, New Haven, CT 06510, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511, USA
| | - Xue S. Davis
- Modern Diet and Physiology Research Center, New Haven, CT 06510, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511, USA
| | - Jelena Djordjevic
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montréal, QC H3A 2B4, Canada
| | - Marilyn Jones-Gotman
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montréal, QC H3A 2B4, Canada
| | - Jessica Trinh
- Modern Diet and Physiology Research Center, New Haven, CT 06510, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511, USA
| | - Zach Hutelin
- Modern Diet and Physiology Research Center, New Haven, CT 06510, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511, USA
| | - Maria G. Veldhuizen
- Department of Anatomy, Faculty of Medicine, Mersin University, Ciftlikkoy Campus, Mersin 33343, Turkey
| | - Leonie Koban
- Lyon Neuroscience Research Center (CRNL), CNRS, INSERM, University Claude Bernard Lyon 1, France
| | - Tor D. Wager
- Department of Psychological and Brain Sciences, Dartmouth College, Hanover, NH 03755, USA
| | - Hedy Kober
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511, USA
- Department of Psychology, Yale University, New Haven, CT 06511, USA
| | - Dana M. Small
- Modern Diet and Physiology Research Center, New Haven, CT 06510, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511, USA
- Department of Psychology, Yale University, New Haven, CT 06511, USA
| |
Collapse
|
12
|
Odor discrimination is immune to the effects of verbal labels. Sci Rep 2023; 13:1742. [PMID: 36720925 PMCID: PMC9889793 DOI: 10.1038/s41598-023-28134-w] [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: 01/20/2022] [Accepted: 01/13/2023] [Indexed: 02/01/2023] Open
Abstract
For many odors that we encounter in daily life, we perceive their qualities without being able to specifically identify their sources-an experience termed the "tip-of-the-nose" phenomenon. Does learning an odor's identity alter our experience of it? Past work has shown that labeling odors can alter how we describe and react to them, but it remains an open question whether such changes extend to the level of perception, making an odor actually smell different. Here, in a set of odor classification experiments we tested whether attaching labels to odors can alter their perceptual discriminability. We found that even for odors whose reported similarity changed markedly when their identities were revealed, their discriminability remained unchanged by labels. Our findings indicate that two critical functions of olfaction-parsing the odor environment and supporting the subjective experience of odor qualities-access distinct odor representations within the olfactory processing stream.
Collapse
|
13
|
Kulason S, Ratnanather JT, Miller MI, Kamath V, Hua J, Yang K, Ma M, Ishizuka K, Sawa A. A comparative neuroimaging perspective of olfaction and higher-order olfactory processing: on health and disease. Semin Cell Dev Biol 2022; 129:22-30. [PMID: 34462249 PMCID: PMC9900497 DOI: 10.1016/j.semcdb.2021.08.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Accepted: 08/18/2021] [Indexed: 02/08/2023]
Abstract
Olfactory dysfunction is often the earliest indicator of disease in a range of neurological and psychiatric disorders. One tempting working hypothesis is that pathological changes in the peripheral olfactory system where the body is exposed to many adverse environmental stressors may have a causal role for the brain alteration. Whether and how the peripheral pathology spreads to more central brain regions may be effectively studied in rodent models, and there is successful precedence in experimental models for Parkinson's disease. It is of interest to study whether a similar mechanism may underlie the pathology of psychiatric illnesses, such as schizophrenia. However, direct comparison between rodent models and humans includes challenges under light of comparative neuroanatomy and experimental methodologies used in these two distinct species. We believe that neuroimaging modality that has been the main methodology of human brain studies may be a useful viewpoint to address and fill the knowledge gap between rodents and humans in this scientific question. Accordingly, in the present review article, we focus on brain imaging studies associated with olfaction in healthy humans and patients with neurological and psychiatric disorders, and if available those in rodents. We organize this review article at three levels: 1) olfactory bulb (OB) and peripheral structures of the olfactory system, 2) primary olfactory cortical and subcortical regions, and 3) associated higher-order cortical regions. This research area is still underdeveloped, and we acknowledge that further validation with independent cohorts may be needed for many studies presented here, in particular those with human subjects. Nevertheless, whether and how peripheral olfactory disturbance impacts brain function is becoming even a hotter topic in the ongoing COVID-19 pandemic, given the risk of long-term changes of mental status associated with olfactory infection of SARS-CoV-2. Together, in this review article, we introduce this underdeveloped but important research area focusing on its implications in neurological and psychiatric disorders, with several pioneered publications.
Collapse
Affiliation(s)
- Sue Kulason
- Center for Imaging Science, Johns Hopkins University, Baltimore, MD, USA; Institute for Computational Medicine, Johns Hopkins University, Baltimore, MD, USA; Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - J Tilak Ratnanather
- Center for Imaging Science, Johns Hopkins University, Baltimore, MD, USA; Institute for Computational Medicine, Johns Hopkins University, Baltimore, MD, USA; Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Michael I Miller
- Center for Imaging Science, Johns Hopkins University, Baltimore, MD, USA; Institute for Computational Medicine, Johns Hopkins University, Baltimore, MD, USA; Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Vidyulata Kamath
- Department of Psychiatry, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Jun Hua
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Kun Yang
- Department of Psychiatry, Johns Hopkins School of Medicine, Baltimore, MD, USA; Johns Hopkins Schizophrenia Center, Baltimore, MD, USA
| | - Minghong Ma
- Department of Neuroscience, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Koko Ishizuka
- Department of Psychiatry, Johns Hopkins School of Medicine, Baltimore, MD, USA; Johns Hopkins Schizophrenia Center, Baltimore, MD, USA
| | - Akira Sawa
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA; Department of Psychiatry, Johns Hopkins School of Medicine, Baltimore, MD, USA; Johns Hopkins Schizophrenia Center, Baltimore, MD, USA; Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD, USA; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
| |
Collapse
|
14
|
Stensola T, Stensola H. Understanding Categorical Learning in Neural Circuits Through the Primary Olfactory Cortex. Front Cell Neurosci 2022; 16:920334. [PMID: 35813505 PMCID: PMC9263292 DOI: 10.3389/fncel.2022.920334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 05/30/2022] [Indexed: 11/25/2022] Open
Abstract
Knowing which elements in the environment are associated with various opportunities and dangers is advantageous. A major role of mammalian sensory systems is to provide information about the identity of such elements which can then be used for adaptive action planning by the animal. Identity-tuned sensory representations are categorical, invariant to nuances in the sensory stream and depend on associative learning. Although categorical representations are well documented across several sensory modalities, these tend to situate synaptically far from the sensory organs which reduces experimenter control over input-output transformations. The formation of such representations is a fundamental neural computation that remains poorly understood. Odor representations in the primary olfactory cortex have several characteristics that qualify them as categorical and identity-tuned, situated only two synapses away from the sensory epithelium. The formation of categorical representations is likely critically dependent on—and dynamically controlled by—recurrent circuitry within the primary olfactory cortex itself. Experiments suggest that the concerted activity of several neuromodulatory systems plays a decisive role in shaping categorical learning through complex interactions with recurrent activity and plasticity in primary olfactory cortex circuits. In this perspective we discuss missing pieces of the categorical learning puzzle, and why several features of olfaction make it an attractive model system for this challenge.
Collapse
|
15
|
Bae J, Kim K, Moon SA, Choe HK, Jin Y, Kang WS, Moon C. Time Course of Odor Categorization Processing. Cereb Cortex Commun 2021; 2:tgab058. [PMID: 34746790 PMCID: PMC8567848 DOI: 10.1093/texcom/tgab058] [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: 06/27/2021] [Revised: 09/13/2021] [Accepted: 09/14/2021] [Indexed: 11/13/2022] Open
Abstract
The brain’s mechanisms for categorizing different odors have long been a research focus. Previous studies suggest that odor categorization may involve multiple neurological processes within the brain with temporal and spatial neuronal activation. However, there is limited evidence regarding temporally mediated mechanisms in humans, especially millisecond odor processing. Such mechanisms may be important because different brain areas may play different roles at a particular activation time during sensory processing. Here, we focused on how the brain categorizes odors at specific time intervals. Using multivariate electroencephalography (EEG) analysis, we found that similarly perceived odors induced similar EEG signals during 50–100, 150–200, and 350–400 ms at the theta frequency. We also found significant activation at 100–150 and 350–400 ms at the gamma frequency. At these two frequencies, significant activation was observed in some olfactory-associated areas, including the orbitofrontal cortex. Our findings provide essential evidence that specific periods may be related to odor quality processing during central olfactory processing.
Collapse
Affiliation(s)
- Jisub Bae
- Brain Engineering Convergence Research Center, Daegu Gyeungbuk Institute of Science and Technology (DGIST), Daegu, South Korea
| | - Kwangsu Kim
- Department of Brain & Cognitive Sciences, Daegu Gyeungbuk Institute of Science and Technology (DGIST), Daegu, South Korea
| | - Sun Ae Moon
- Department of Brain & Cognitive Sciences, Daegu Gyeungbuk Institute of Science and Technology (DGIST), Daegu, South Korea
| | - Han Kyoung Choe
- Department of Brain & Cognitive Sciences, Daegu Gyeungbuk Institute of Science and Technology (DGIST), Daegu, South Korea
| | - Youngsun Jin
- Department of Psychology, Kyungpook National University, Daegu, South Korea
| | - Won-Seok Kang
- Convergence Research Advanced Centre for Olfaction, Daegu Gyeungbuk Institute of Science and Technology (DGIST), Daegu, South Korea
| | - Cheil Moon
- Department of Brain & Cognitive Sciences, Daegu Gyeungbuk Institute of Science and Technology (DGIST), Daegu, South Korea
| |
Collapse
|
16
|
Callara AL, Greco A, Frasnelli J, Rho G, Vanello N, Scilingo EP. Cortical network and connectivity underlying hedonic olfactory perception. J Neural Eng 2021; 18. [PMID: 34547740 DOI: 10.1088/1741-2552/ac28d2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 09/21/2021] [Indexed: 12/15/2022]
Abstract
Objective.The emotional response to olfactory stimuli implies the activation of a complex cascade of events triggered by structures lying in the limbic system. However, little is known about how this activation is projected up to cerebral cortex and how different cortical areas dynamically interact each other.Approach.In this study, we acquired EEG from human participants performing a passive odor-perception task with odorants conveying positive, neutral and negative valence. A novel methodological pipeline integrating global field power (GFP), independent component analysis (ICA), dipole source localization was applied to estimate effective connectivity in the challenging scenario of single-trial low-synchronized stimulation.Main results.We identified the brain network and the neural paths, elicited at different frequency bands, i.e.θ(4-7Hz),α(8-12Hz)andβ(13-30Hz), involved in odor valence processing. This brain network includes the orbitofrontal cortex (OFC), the cingulate gyrus (CgG), the superior temporal gyrus (STG), the posterior cingulate cortex/precuneus (PCC/PCu) and the parahippocampal gyrus (PHG). It was analyzed using a time-varying multivariate autoregressive model to resolve time-frequency causal interactions. Specifically, the OFC acts as the main node for odor perception and evaluation of pleasant and unpleasant stimuli, whereas no specific path was observed for a neutral stimulus.Significance.The results introduce new evidences on the role of the OFC during hedonic perception and underpin its specificity during the odor valence assessment. Our findings suggest that, after the odor onset different, bidirectional interactions occur between the OFC and other brain regions associated with emotion recognition/categorization and memory according to the stimulus valence. This outcome unveils how the hedonic olfactory network dynamically changes based on odor valence.
Collapse
Affiliation(s)
- Alejandro Luis Callara
- Research Center 'E. Piaggio', School of Engineering, University of Pisa, Largo Lucio Lazzarino 1, 56122 Pisa, Italy.,Dipartimento di Ingegneria dell'Informazione, University of Pisa, Via G. Caruso 16, 56122 Pisa, Italy
| | - Alberto Greco
- Research Center 'E. Piaggio', School of Engineering, University of Pisa, Largo Lucio Lazzarino 1, 56122 Pisa, Italy.,Dipartimento di Ingegneria dell'Informazione, University of Pisa, Via G. Caruso 16, 56122 Pisa, Italy
| | - Johannes Frasnelli
- Département d'anatomie, Université du Québec à Trois-Rivières, 3351, boul. des Forges, C.P. 500, G9A 5H7
- Local 3439 L.-P, Trois-Rivières, Québec, Canada
| | - Gianluca Rho
- Dipartimento di Ingegneria dell'Informazione, University of Pisa, Via G. Caruso 16, 56122 Pisa, Italy
| | - Nicola Vanello
- Research Center 'E. Piaggio', School of Engineering, University of Pisa, Largo Lucio Lazzarino 1, 56122 Pisa, Italy.,Dipartimento di Ingegneria dell'Informazione, University of Pisa, Via G. Caruso 16, 56122 Pisa, Italy
| | - Enzo Pasquale Scilingo
- Research Center 'E. Piaggio', School of Engineering, University of Pisa, Largo Lucio Lazzarino 1, 56122 Pisa, Italy.,Dipartimento di Ingegneria dell'Informazione, University of Pisa, Via G. Caruso 16, 56122 Pisa, Italy
| |
Collapse
|
17
|
Donoshita Y, Choi US, Ban H, Kida I. Assessment of olfactory information in the human brain using 7-Tesla functional magnetic resonance imaging. Neuroimage 2021; 236:118212. [PMID: 34082117 DOI: 10.1016/j.neuroimage.2021.118212] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 05/13/2021] [Accepted: 05/25/2021] [Indexed: 10/21/2022] Open
Abstract
Olfaction could prove to be an early marker of neurodegenerative diseases, including Alzheimer's and Parkinson's diseases. To use olfaction for disease diagnosis, elucidating the standard olfactory functions in healthy humans is necessary. However, the olfactory function in the human brain is less frequently assessed because of methodological difficulties associated with olfactory-related cerebral areas. Using ultra-high fields (UHF), functional magnetic resonance imaging (fMRI) with high spatial resolution and sensitivity may allow for the measurement of activation in the cerebral areas. This study aimed to apply 7-Tesla fMRI to assess olfactory function in the human brain by exposing individuals to four different odorants for 8 s. We found that olfactory stimulation mainly activated the piriform and orbitofrontal cortex in addition to the amygdala. Among these regions, univariate fMRI analysis indicated that subjective odor intensity significantly correlated with the averaged fMRI signals in the piriform cortex but not with subjective hedonic tone in any region. In contrast, multivariate fMRI analysis showed that subjective hedonic tone could be discriminated from the fMRI response patterns in the posterior orbitofrontal cortex. Thus, the piriform cortex is mainly associated with subjective odor intensity, whereas the posterior orbitofrontal cortex are involved in the discrimination of the subjective hedonic tone of the odorant. UHF-fMRI may be useful for assessing olfactory function in the human brain.
Collapse
Affiliation(s)
- Yuka Donoshita
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, Suita, Osaka 565-0871, Japan; Daikin Industries, Ltd., Settsu, Osaka 566-8585, Japan
| | - Uk-Su Choi
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, Suita, Osaka 565-0871, Japan; Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Hiroshi Ban
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, Suita, Osaka 565-0871, Japan; Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Ikuhiro Kida
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, Suita, Osaka 565-0871, Japan; Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan.
| |
Collapse
|
18
|
Pellegrino R, Hörberg T, Olofsson J, Luckett CR. Duality of Smell: Route-Dependent Effects on Olfactory Perception and Language. Chem Senses 2021; 46:6278057. [PMID: 34007980 DOI: 10.1093/chemse/bjab025] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Olfactory research in humans has largely focused on odors perceived via sniffing, orthonasal olfaction, whereas odors perceived from the mouth, retronasal olfaction, are less well understood. Prior work on retronasally presented odors involves animal models and focus mainly on odor sensitivity, but little is known about retronasal olfactory perception and cognition in humans. In this study, we compared orthonasal and retronasal odor presentation routes to investigate differences in odor descriptions and evaluations. Thirty-six individuals participated in a within-subjects study using twelve odors (varying in pleasantness and edibility) in perceptual and semantic tasks. Orthonasal presentation was associated with a better ability to identify odors, and with more concrete (and source-based) language. Exploratory analyses revealed that whereas orthonasal odors were described with words that had visual associations, retronasal odors were described with words that had interoceptive associations. Interestingly, these route-dependent differences in descriptor usage were not explained by differences in sensitivity and intensity, suggesting instead a cognitive and linguistic processing difference between odors presented orthonasally and retronasally. Our results indicate that olfaction is, in fact, a dual sense, in which the routes change the perception of an odor.
Collapse
Affiliation(s)
- Robert Pellegrino
- Department of Food Science, University of Tennessee, 2510 River Drive, Knoxville, Tennessee, USA
| | - Thomas Hörberg
- Gösta Ekman Laboratory, Department of Psychology Stockholm University, Frescati hagväg 9, Stockholm, Sweden.,Department of Linguistics, Stockholm University, Universitetsvägen 10C, 114 18 Stockholm, Sweden
| | - Jonas Olofsson
- Gösta Ekman Laboratory, Department of Psychology Stockholm University, Frescati hagväg 9, Stockholm, Sweden
| | - Curtis R Luckett
- Department of Food Science, University of Tennessee, 2510 River Drive, Knoxville, Tennessee, USA
| |
Collapse
|
19
|
Zhou G, Olofsson JK, Koubeissi MZ, Menelaou G, Rosenow J, Schuele SU, Xu P, Voss JL, Lane G, Zelano C. Human hippocampal connectivity is stronger in olfaction than other sensory systems. Prog Neurobiol 2021; 201:102027. [PMID: 33640412 DOI: 10.1016/j.pneurobio.2021.102027] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 01/20/2021] [Accepted: 02/21/2021] [Indexed: 12/17/2022]
Abstract
During mammalian evolution, primate neocortex expanded, shifting hippocampal functional networks away from primary sensory cortices, towards association cortices. Reflecting this rerouting, human resting hippocampal functional networks preferentially include higher association cortices, while those in rodents retained primary sensory cortices. Research on human visual, auditory and somatosensory systems shows evidence of this rerouting. Olfaction, however, is unique among sensory systems in its relative structural conservation throughout mammalian evolution, and it is unknown whether human primary olfactory cortex was subject to the same rerouting. We combined functional neuroimaging and intracranial electrophysiology to directly compare hippocampal functional networks across human sensory systems. We show that human primary olfactory cortex-including the anterior olfactory nucleus, olfactory tubercle and piriform cortex-has stronger functional connectivity with hippocampal networks at rest, compared to other sensory systems. This suggests that unlike other sensory systems, olfactory-hippocampal connectivity may have been retained in mammalian evolution. We further show that olfactory-hippocampal connectivity oscillates with nasal breathing. Our findings suggest olfaction might provide insight into how memory and cognition depend on hippocampal interactions.
Collapse
Affiliation(s)
- Guangyu Zhou
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
| | - Jonas K Olofsson
- Department of Psychology, Stockholm University, Stockholm, Sweden; Emotional Brain Institute, Nathan S. Kline Institute, Orangeburg, NY, USA; Department of Child and Adolescent Psychiatry, New York University School of Medicine, New York, NY, USA
| | | | | | - Joshua Rosenow
- Department of Neurosurgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Stephan U Schuele
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Pengfei Xu
- Beijing Key Laboratory of Applied Experimental Psychology, Faculty of Psychology, Beijing Normal University, Beijing, China; Center for Neuroimaging, Shenzhen Institute of Neuroscience, Shenzhen, China; Guangdong-Hong Kong-Macao Greater Bay Area Research Institute for Neuroscience and Neurotechnologies, Kwun Tong, Hong Kong, China
| | - Joel L Voss
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Department of Medical Social Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Gregory Lane
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Christina Zelano
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
| |
Collapse
|
20
|
Gorodisky L, Livne E, Weiss T, Weissbrod A, Weissgross R, Mishor E, Furman-Haran E, Sobel N. Odor Canopy: A Method for Comfortable Odorant Delivery in MRI. Chem Senses 2021; 46:6060058. [PMID: 33388762 PMCID: PMC8286093 DOI: 10.1093/chemse/bjaa085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Functional magnetic resonance imaging (fMRI) has become the leading method for measuring the human brain response to sensory stimuli. However, olfaction fMRI lags behind vision and audition fMRI for 2 primary reasons: First, the olfactory brain areas are particularly susceptible to imaging artifacts, and second, the olfactory stimulus is particularly difficult to control in the fMRI environment. A component of the latter is related to the odorant delivery human–machine interface, namely the point where odorants exit the dispensing apparatus to reach at the nose. Previous approaches relied on either nasal cannulas or nasal masks, each associated with particular drawbacks and discomforts. Here, we provide detailed descriptions and instructions for transforming the MRI head-coil into an olfactory microenvironment, or odor canopy, where odorants can be switched on and off in less than 150 ms without cannula or mask. In a proof-of-concept experiment, we demonstrate that odor canopy provides for clearly dissociable odorant presence and absence, with no nonolfactory cues. Moreover, we find that odor canopy is rated more comfortable than nasal mask, and we demonstrate that using odor canopy in the fMRI generates a typical olfactory brain response. We conclude in recommending this approach for minimized discomfort in fMRI of olfaction.
Collapse
Affiliation(s)
- Lior Gorodisky
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel.,Department of Neurobiology, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel
| | - Ethan Livne
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel.,Department of Neurobiology, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel
| | - Tali Weiss
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel
| | - Aharon Weissbrod
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel.,Department of Neurobiology, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel
| | - Reut Weissgross
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel.,Department of Neurobiology, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel
| | - Eva Mishor
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel.,Department of Neurobiology, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel
| | - Edna Furman-Haran
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel
| | - Noam Sobel
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel.,Department of Neurobiology, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel
| |
Collapse
|
21
|
Bhattacharjee AS, Joshi SV, Naik S, Sangle S, Abraham NM. Quantitative assessment of olfactory dysfunction accurately detects asymptomatic COVID-19 carriers. EClinicalMedicine 2020; 28:100575. [PMID: 33083773 PMCID: PMC7562772 DOI: 10.1016/j.eclinm.2020.100575] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/16/2020] [Accepted: 09/17/2020] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND COVID-19 threatens the global community because a large fraction of infected people are asymptomatic, yet can effectively transmit SARS-CoV-2. Finding and isolating these silent carriers is a crucial step in confining the spread of the disease. A sudden loss of the sense of smell has been self-reported by COVID-19 patients across different countries, consistent with expression of the molecular factors mediating SARS-CoV-2 uptake into human olfactory epithelial supporting cells. However, precise quantification of olfactory loss in asymptomatic COVID-19 carriers is missing to date. METHODS To quantify olfactory functions in asymptomatic COVID-19 patients, we designed an olfactory-action meter that determines detectability indices at different odor concentrations and an olfactory matching accuracy score using monomolecular odors. The optimization of test parameters allowed us to reliably and accurately assess olfactory deficits in a patient within 20 minutes. FINDINGS Measurement of detection indices at low concentrations revealed a 50% reduction in asymptomatic COVID-19 carriers. Further, patients with better detection scores showed significantly reduced olfactory matching accuracies compared to normal healthy subjects. Our quantification of olfactory loss, considering all parameters, identified 82% of the asymptomatic SARS-CoV-2 carriers with olfactory deficits. However, on subjective evaluation, only 15% of the patients noticed a compromised ability to smell. INTERPRETATION Compromised olfactory fitness can serve as a strong basis for identifying asymptomatic COVID-19 patients. Detailed design specifications and protocols provided here should enable the development of a sensitive, fast, and economical screening strategy that can be administered to large populations to prevent the rapid spread of COVID-19. FUNDING This work was supported by the DBT - Wellcome Trust India Alliance intermediate grant (IA/I/14/1/501,306 to N.A.) and UGC NET Fellowship (A.B.). All the funding sources played no roles in the study.
Collapse
Affiliation(s)
| | - Samir V. Joshi
- Byramjee Jeejeebhoy Government Medical College and Sassoon General Hospitals (BJGMC & SGH), Pune, Maharashtra, 411001, India
| | - Shilpa Naik
- Byramjee Jeejeebhoy Government Medical College and Sassoon General Hospitals (BJGMC & SGH), Pune, Maharashtra, 411001, India
| | - Shashikala Sangle
- Byramjee Jeejeebhoy Government Medical College and Sassoon General Hospitals (BJGMC & SGH), Pune, Maharashtra, 411001, India
| | - Nixon M. Abraham
- Indian Institute of Science Education and Research (IISER), Pune, Maharashtra, 411008, India
| |
Collapse
|
22
|
DeGuzman P, Jain A, Tabert MH, Parra LC. Olfaction Modulates Inter-Subject Correlation of Neural Responses. Front Neurosci 2020; 14:702. [PMID: 32754012 PMCID: PMC7366795 DOI: 10.3389/fnins.2020.00702] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Accepted: 06/09/2020] [Indexed: 11/13/2022] Open
Abstract
Odors can be powerful stimulants. It is well-established that odors provide strong cues for recall of locations, people and events. The effects of specific scents on other cognitive functions are less well-established. We hypothesized that scents with different odor qualities will have a different effect on attention. To assess attention, we used Inter-Subject Correlation of the EEG because this metric is strongly modulated by attentional engagement with natural audiovisual stimuli. We predicted that scents known to be "energizing" would increase Inter-Subject Correlation during watching of videos as compared to "calming" scents. In a first experiment, we confirmed this for eucalyptol and linalool while participants watched animated autobiographical narratives. The result was replicated in a second experiment, but did not generalize to limonene, also considered an "energizing" odorant. In a third, double-blind experiment, we tested a battery of scents including single molecules, as well as mixtures, as participants watched various short video clips. We found a varying effect of odor on Inter-Subject Correlation across the various scents. This study provides a basis for reliably and reproducibly assessing effects of odors on brain activity. Future research is needed to further explore the effect of scent-based up-modulation in engagement on learning and memory performance. Educators, product developers and fragrance brands might also benefit from such objective neurophysiological measures.
Collapse
Affiliation(s)
| | - Anshul Jain
- International Flavors & Fragrances, Inc., R&D, Union Beach, NJ, United States
| | - Matthias H. Tabert
- International Flavors & Fragrances, Inc., R&D, Union Beach, NJ, United States
| | - Lucas C. Parra
- Department of Biomedical Engineering, City College of New York, New York, NY, United States
| |
Collapse
|
23
|
Structure and flexibility in cortical representations of odour space. Nature 2020; 583:253-258. [PMID: 32612230 PMCID: PMC7450987 DOI: 10.1038/s41586-020-2451-1] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 04/02/2020] [Indexed: 02/08/2023]
Abstract
The cortex organizes sensory information to enable discrimination and generalization1–4. Systematic representations of chemical odor space have not been described in olfactory cortex, and so it remains unclear how odor relationships are encoded to place chemically distinct but similar odors, like lemon and orange, into perceptual categories, like citrus5–7. Here we demonstrate that both the piriform cortex (PCx) and its sensory inputs from the olfactory bulb represent chemical odor relationships through correlated patterns of activity. However, cortical odor codes differ from those in the bulb: cortex more strongly clusters together representations for related odors, selectively rewrites pairwise odor relationships, and better matches odor perception. The bulb-to-cortex transformation depends upon the associative network originating within PCx, and can be reshaped by passive odor experience. Thus, cortex actively builds a structured representation of chemical odor space that highlights odor relationships; this representation is similar across individuals but remains plastic, suggesting a means through which the olfactory system can assign related odor cues to common and yet personalized percepts.
Collapse
|
24
|
Wilson DA, Fleming G, Vervoordt SM, Coureaud G. Cortical processing of configurally perceived odor mixtures. Brain Res 2020; 1729:146617. [PMID: 31866364 PMCID: PMC6941848 DOI: 10.1016/j.brainres.2019.146617] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 12/12/2019] [Accepted: 12/17/2019] [Indexed: 02/01/2023]
Abstract
Most odors are not composed of a single volatile chemical species, but rather are mixtures of many different volatile molecules, the perception of which is dependent on the identity and relative concentrations of the components. Changing either the identity or ratio of components can lead to shifts between configural and elemental perception of the mixture. For example, a 30/70 ratio of ethyl isobutyrate (odorant A, a strawberry scent) and ethyl maltol (odorant B, a caramel scent) is perceived as pineapple by humans - a configural percept distinct from the components. In contrast, a 68/32 ratio of the same odorants is perceived elementally, and is identified as the component odors. Here, we examined single-unit responses in the anterior and posterior piriform cortex (aPCX and pPCX) of mice to these A and B mixtures. We first demonstrate that mouse behavior is consistent with a configural/elemental perceptual shift as concentration ratio varies. We then compared responses to the configural mixture to those evoked by the elemental mixture, as well as to the individual components. Hierarchical cluster analyses suggest that in the mouse aPCX, the configural mixture was coded as distinct from both components, while the elemental mixture was coded as similar to the components. In contrast, mixture perception did not predict pPCX ensemble coding. Similar electrophysiological results were also observed in rats. The results suggest similar perceptual characteristics of the AB mixture across species, and a division in the roles of aPCX and pPCX in the coding of configural and elemental odor mixtures.
Collapse
Affiliation(s)
- Donald A Wilson
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA; Child & Adolescent Psychiatry, NYU School of Medicine, New York, NY, USA.
| | - Gloria Fleming
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Samantha M Vervoordt
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Gérard Coureaud
- Lyon Neuroscience Research Center, INSERM U1028/CNRS UMR 5292/Lyon 1 University, Bron, France.
| |
Collapse
|
25
|
Wang L, Zhang Z, Chen J, Manyande A, Haddad R, Liu Q, Xu F. Cell-Type-Specific Whole-Brain Direct Inputs to the Anterior and Posterior Piriform Cortex. Front Neural Circuits 2020; 14:4. [PMID: 32116571 PMCID: PMC7019026 DOI: 10.3389/fncir.2020.00004] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 01/21/2020] [Indexed: 12/20/2022] Open
Abstract
The piriform cortex (PC) is a key brain area involved in both processing and coding of olfactory information. It is implicated in various brain disorders, such as epilepsy, Alzheimer’s disease, and autism. The PC consists of the anterior (APC) and posterior (PPC) parts, which are different anatomically and functionally. However, the direct input networks to specific neuronal populations within the APC and PPC remain poorly understood. Here, we mapped the whole-brain direct inputs to the two major neuronal populations, the excitatory glutamatergic principal neurons and inhibitory γ-aminobutyric acid (GABA)-ergic interneurons within the APC and PPC using the rabies virus (RV)-mediated retrograde trans-synaptic tracing system. We found that for both types of neurons, APC and PPC share some similarities in input networks, with dominant inputs originating from the olfactory region (OLF), followed by the cortical subplate (CTXsp), isocortex, cerebral nuclei (CNU), hippocampal formation (HPF) and interbrain (IB), whereas the midbrain (MB) and hindbrain (HB) were rarely labeled. However, APC and PPC also show distinct features in their input distribution patterns. For both types of neurons, the input proportion from the OLF to the APC was higher than that to the PPC; while the PPC received higher proportions of inputs from the HPF and CNU than the APC did. Overall, our results revealed the direct input networks of both excitatory and inhibitory neuronal populations of different PC subareas, providing a structural basis to analyze the diverse PC functions.
Collapse
Affiliation(s)
- Li Wang
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, China.,Center for Brain Science, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, China
| | - Zhijian Zhang
- Center for Brain Science, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, China
| | - Jiacheng Chen
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Anne Manyande
- School of Human and Social Sciences, University of West London, Middlesex, United Kingdom
| | - Rafi Haddad
- The Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan, Israel
| | - Qing Liu
- Center for Brain Science, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, China.,University of the Chinese Academy of Sciences, Beijing, China
| | - Fuqiang Xu
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, China.,Center for Brain Science, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, China.,University of the Chinese Academy of Sciences, Beijing, China.,Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China.,Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China
| |
Collapse
|
26
|
Seubert J, Kalpouzos G, Larsson M, Hummel T, Bäckman L, Laukka EJ. Temporolimbic cortical volume is associated with semantic odor memory performance in aging. Neuroimage 2020; 211:116600. [PMID: 32018003 DOI: 10.1016/j.neuroimage.2020.116600] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 01/10/2020] [Accepted: 01/31/2020] [Indexed: 12/30/2022] Open
Abstract
Olfactory function, and specifically semantic olfactory memory (i.e., odor identification), has frequently been shown to predict cognitive functioning across multiple domains in old age. This observation suggests that olfactory function can serve as a marker for the integrity of temporolimbic cortical networks, but a clear delineation of this association is still missing. To address this issue, the present study employed voxel-based morphometry in a region of interest-based design to determine the extent to which gray matter volumes of core olfactory and memory areas are associated with olfactory memory performance in an aging population free from neurodegenerative disease. We further aimed to determine potential overlap in structural anatomical correlates, and differences in association strength, for semantic and episodic olfactory memory. Structural magnetic resonance imaging (MRI), episodic and semantic odor memory and episodic and semantic verbal memory data were collected in 422 participants from the Swedish National Study on Aging and Care in Kungsholmen (SNAC-K), all aged ≥ 60 years. Controlling for age and education, semantic, but not episodic, olfactory memory was positively related to gray matter volume in a cluster extending from the anterior hippocampus and amygdala into the posterior piriform cortex. The observed associations remained even when verbal memory performance was controlled for, supporting a link between the olfactory memory domain and cortical volume over and above more generalized memory abilities. As such, our data provide evidence for distinct functional-structural associations for semantic odor memory, supporting the idea of temporolimbic integrity as a neurobiological substrate linking olfactory function to cognitive health in old age.
Collapse
Affiliation(s)
- Janina Seubert
- Department of Neurobiology, Care Sciences and Society, Aging Research Center, Karolinska Institutet and Stockholm University, Stockholm, Sweden; Department of Clinical Neuroscience, Psychology Division, Karolinska Institutet, Stockholm, Sweden.
| | - Grégoria Kalpouzos
- Department of Neurobiology, Care Sciences and Society, Aging Research Center, Karolinska Institutet and Stockholm University, Stockholm, Sweden
| | - Maria Larsson
- Gösta Ekman's Laboratory, Department of Psychology, Stockholm University, Stockholm, Sweden
| | - Thomas Hummel
- Department of Otorhinolaryngology, TU Dresden, Dresden, Germany
| | - Lars Bäckman
- Department of Neurobiology, Care Sciences and Society, Aging Research Center, Karolinska Institutet and Stockholm University, Stockholm, Sweden
| | - Erika J Laukka
- Department of Neurobiology, Care Sciences and Society, Aging Research Center, Karolinska Institutet and Stockholm University, Stockholm, Sweden; Stockholm Gerontology Research Center, Stockholm, Sweden
| |
Collapse
|
27
|
Strauch C, Manahan-Vaughan D. Orchestration of Hippocampal Information Encoding by the Piriform Cortex. Cereb Cortex 2020; 30:135-147. [PMID: 31220213 PMCID: PMC7029697 DOI: 10.1093/cercor/bhz077] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 03/08/2019] [Accepted: 03/18/2019] [Indexed: 01/03/2023] Open
Abstract
The hippocampus utilizes olfactospatial information to encode sensory experience by means of synaptic plasticity. Odor exposure is also a potent impetus for hippocampus-dependent memory retrieval. Here, we explored to what extent the piriform cortex directly impacts upon hippocampal information processing and storage. In behaving rats, test-pulse stimulation of the anterior piriform cortex (aPC) evoked field potentials in the dentate gyrus (DG). Patterned stimulation of the aPC triggered both long-term potentiation (LTP > 24 h) and short-term depression (STD), in a frequency-dependent manner. Dual stimulation of the aPC and perforant path demonstrated subordination of the aPC response, which was nonetheless completely distinct in profile to perforant path-induced DG plasticity. Correspondingly, patterned aPC stimulation resulted in somatic immediate early gene expression in the DG that did not overlap with responses elicited by perforant path stimulation. Our results support that the piriform cortex engages in specific control of hippocampal information processing and encoding. This process may underlie the unique role of olfactory cues in information encoding and retrieval of hippocampus-dependent associative memories.
Collapse
Affiliation(s)
- Christina Strauch
- Department of Neurophysiology, Medical Faculty
- International Graduate School for Neuroscience, Ruhr University Bochum, Universitaetsstr. Bochum, Germany
| | - Denise Manahan-Vaughan
- Department of Neurophysiology, Medical Faculty
- International Graduate School for Neuroscience, Ruhr University Bochum, Universitaetsstr. Bochum, Germany
| |
Collapse
|
28
|
Neural correlates of moral goodness and moral beauty judgments. Brain Res 2020; 1726:146534. [PMID: 31669285 DOI: 10.1016/j.brainres.2019.146534] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 10/21/2019] [Accepted: 10/23/2019] [Indexed: 12/30/2022]
Abstract
The objects of moral goodness and moral beauty judgments both generally refer to the positive moral acts or virtues of humans, and goodness must precede moral beauty. The main difference is that moral beauty, but not moral goodness, triggers emotional elevation. However, little is known about the neural mechanisms involved in both judgments. In the current study, 28 healthy female participants were scanned when they rated the good and beautiful extent of positive moral acts in daily life depicted in scene drawings to investigate the neural systems supporting moral goodness and moral beauty, specifically to test whether neural activity associated with moral beauty is same or different than moral goodness. The conjunction analysis of the contrasts between moral goodness judgment and moral beauty judgment identified the involvement of the left inferior orbitofrontal cortex (OFC), suggesting that the two judgments recruited the activity of a common brain region. Importantly, compared with the moral goodness judgment, the moral beauty judgment induced greater activity in more advanced cortical regions implicated in elevated emotions, including the anterior cingulate cortex (ACC), medial prefrontal cortex (mPFC), superior frontal gyrus (SFG) and the left temporo-parietal junction (TPJ). These regions have been strongly correlated with the cognitive aspects of moral cognition, including theory of mind (ToM). In addition, moral beauty judgment also activated brain regions implicated in empathy including the midline structures and the anterior insula. Based on these results, the brain harbors neural systems for common and for domain-specific evaluations of moral goodness and moral beauty judgments. Our study thus provides novel and compelling neural evidence for the essence of moral beauty and advances the current knowledge of the neural mechanisms underlying the beauty-is-good stereotype.
Collapse
|
29
|
Bae J, Yi JY, Moon C. Odor quality profile is partially influenced by verbal cues. PLoS One 2019; 14:e0226385. [PMID: 31830119 PMCID: PMC6907808 DOI: 10.1371/journal.pone.0226385] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 11/25/2019] [Indexed: 11/19/2022] Open
Abstract
Characterizing an odor quality is difficult for humans. Ever-increasing physiological and behavioral studies have characterized odor quality and demonstrated high performance of human odor categorization. However, there are no precise methods for measuring the multidimensional axis of an odor quality. Furthermore, it can be altered by individual experience, even when using existing measurement methods for the multidimensional axis of odor such as odor profiling. It is, therefore, necessary to characterize patterns of odor quality with odor profiling and observe alterations in odor profiles under the influence of subjective rating conditions such as verbal cues. Considering the high performance of human odor categorization, we hypothesized that odor may have specific odor quality that is scarcely altered by verbal cues. We assessed odor responses to isovaleric acid with and without verbal cues and compared the results in each stimulation condition. We found that verbal cues influenced the rating of odor quality descriptors. Verbal cues weakly influenced the odor quality descriptors of high-rated value (upper 25%) compared to odor quality descriptors of low-rated value (lower 75%) by the survey test. Even under different verbal cue conditions, the same odor was classified in the same class when using high-rated odor quality descriptors. Our study suggests that people extract essential odor quality descriptors that represent the odor itself in order to efficiently quantify odor quality.
Collapse
Affiliation(s)
- Jisub Bae
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea
| | - Ju-Yeon Yi
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea
| | - Cheil Moon
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea
- Convergence Research Advanced Centre for Olfaction, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea
- * E-mail:
| |
Collapse
|
30
|
Bathini P, Brai E, Auber LA. Olfactory dysfunction in the pathophysiological continuum of dementia. Ageing Res Rev 2019; 55:100956. [PMID: 31479764 DOI: 10.1016/j.arr.2019.100956] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 07/29/2019] [Accepted: 08/26/2019] [Indexed: 12/21/2022]
Abstract
Sensory capacities like smell, taste, hearing, vision decline with aging, but increasing evidence show that sensory dysfunctions are one of the early signs diagnosing the conversion from physiological to pathological brain state. Smell loss represents the best characterized sense in clinical practice and is considered as one of the first preclinical signs of Alzheimer's and Parkinson's disease, occurring a decade or more before the onset of cognitive and motor symptoms. Despite the numerous scientific reports and the adoption in clinical practice, the etiology of sensory damage as prodromal of dementia remains largely unexplored and more studies are needed to resolve the mechanisms underlying sensory network dysfunction. Although both cognitive and sensory domains are progressively affected, loss of sensory experience in early stages plays a major role in reducing the autonomy of demented people in their daily tasks or even possibly contributing to their cognitive decline. Interestingly, the chemosensory circuitry is devoid of a blood brain barrier, representing a vulnerable port of entry for neurotoxic species that can spread to the brain. Furthermore, the exposure of the olfactory system to the external environment make it more susceptible to mechanical injury and trauma, which can cause degenerative neuroinflammation. In this review, we will summarize several findings about chemosensory impairment signing the conversion from healthy to pathological brain aging and we will try to connect those observations to the promising research linking environmental influences to sporadic dementia. The scientific body of knowledge will support the use of chemosensory diagnostics in the presymptomatic stages of AD and other biomarkers with the scope of finding treatment strategies before the onset of the disease.
Collapse
Affiliation(s)
- Praveen Bathini
- Department of Medicine, University of Fribourg, Fribourg, Switzerland
| | - Emanuele Brai
- VIB-KU Leuven Center for Brain & Disease Research, Laboratory for the Research of Neurodegenerative Diseases, Leuven, Belgium
| | - Lavinia Alberi Auber
- Department of Medicine, University of Fribourg, Fribourg, Switzerland; Swiss Integrative Center of Human Health, Fribourg, Switzerland.
| |
Collapse
|
31
|
Zhang H, Ji D, Yin J, Wang Z, Zhou Y, Ni H, Liu Y. Olfactory fMRI Activation Pattern Across Different Concentrations Changes in Alzheimer's Disease. Front Neurosci 2019; 13:786. [PMID: 31417348 PMCID: PMC6682702 DOI: 10.3389/fnins.2019.00786] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 07/15/2019] [Indexed: 11/26/2022] Open
Abstract
The olfactory involvement is an early feature of Alzheimer’s disease (AD). Olfactory functional MRI (fMRI) is an objective method to evaluate the olfactory function, but might be affected by the individual variation and the magnetic susceptibility artifact of basis cranii. To improve the reliability of olfactory fMRI, we explored the response of primary olfactory cortex (POC) across three different concentrations of odors. Fourty-four normal controls, 46 subjects with mild cognitive impairment (MCI), and 44 patients with AD underwent olfactory fMRI using lavender stimuli of three different (0.10, 0.33, and 1.00%) concentrations during one fMRI sequence with a 3.0T MRI scanner. The numbers of activated voxels in the POC, especially the activation changes during different concentrations were, analyzed. The POC activation pattern of controls showed olfactory adaptation at the higher concentration, whereas the AD patients showed not only increased olfactory threshold but also a lack of olfactory habituation. Five types of activation patterns across different concentrations were summarized to evaluate the olfactory function. The results showed that the activation pattern effectively found 40/44 (90.9%) of the ADs with impaired habituation, whereas 31/44 (70.5%) of the normal controls showed normal olfactory habituation. In MCIs, 29/46 (63.0%) of subjects showed impaired habituation. This finding indicates that the POC activation pattern of olfactory fMRI across different concentrations is useful in evaluating the olfactory function, which is important in the detection of early AD among MCI cases.
Collapse
Affiliation(s)
- Hui Zhang
- Department of Radiology, Tianjin First Central Hospital, Tianjin, China.,Department of Radiology, First Affiliated Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Dongxu Ji
- Department of Radiology, Tianjin First Central Hospital, Tianjin, China
| | - Jianzhong Yin
- Department of Radiology, Tianjin First Central Hospital, Tianjin, China
| | - Zhiyun Wang
- Department of Neurology, Tianjin First Central Hospital, Tianjin, China
| | - Yuying Zhou
- Department of Neurology, Tianjin Huanhu Hospital, Tianjin, China
| | - Hongyan Ni
- Department of Radiology, Tianjin First Central Hospital, Tianjin, China
| | - Yawu Liu
- Departments of Clinical Radiology and Neurology, Kuopio University Hospital, University of Eastern Finland, Kuopio, Finland
| |
Collapse
|
32
|
Zhou G, Lane G, Cooper SL, Kahnt T, Zelano C. Characterizing functional pathways of the human olfactory system. eLife 2019; 8:47177. [PMID: 31339489 PMCID: PMC6656430 DOI: 10.7554/elife.47177] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 07/09/2019] [Indexed: 11/23/2022] Open
Abstract
The central processing pathways of the human olfactory system are not fully understood. The olfactory bulb projects directly to a number of cortical brain structures, but the distinct networks formed by projections from each of these structures to the rest of the brain have not been well-defined. Here, we used functional magnetic resonance imaging and k-means clustering to parcellate human primary olfactory cortex into clusters based on whole-brain functional connectivity patterns. Resulting clusters accurately corresponded to anterior olfactory nucleus, olfactory tubercle, and frontal and temporal piriform cortices, suggesting dissociable whole-brain networks formed by the subregions of primary olfactory cortex. This result was replicated in an independent data set. We then characterized the unique functional connectivity profiles of each subregion, producing a map of the large-scale processing pathways of the human olfactory system. These results provide insight into the functional and anatomical organization of the human olfactory system.
Collapse
Affiliation(s)
- Guangyu Zhou
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, United States
| | - Gregory Lane
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, United States
| | - Shiloh L Cooper
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, United States
| | - Thorsten Kahnt
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, United States.,Department of Psychology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, United States
| | - Christina Zelano
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, United States
| |
Collapse
|
33
|
Koehler L, Fournel A, Albertowski K, Roessner V, Gerber J, Hummel C, Hummel T, Bensafi M. Impaired Odor Perception in Autism Spectrum Disorder Is Associated with Decreased Activity in Olfactory Cortex. Chem Senses 2019; 43:627-634. [PMID: 30219913 DOI: 10.1093/chemse/bjy051] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Autism Spectrum Disorders (ASDs) are characterized by atypical sensory functioning in the visual, tactile, and auditory systems. Although less explored, olfactory changes have been reported in ASD patients. To explore these changes on a neural level, 18 adults with ASD and 18 healthy neurotypical controls were examined in a 2-phase study. Participants were first tested for odor threshold and odor identification. Then, (i) structural magnetic resonance (MR) images of the olfactory bulb were acquired, and (ii) a functional MR imaging olfaction study was conducted. ASD patients exhibited decreased function for odor thresholds and odor identification; this was accompanied by a relatively decreased activation in the piriform cortex. In conclusion, these findings suggest, that the known alterations in olfaction in ASD are rooted in the primary olfactory cortex.
Collapse
Affiliation(s)
- L Koehler
- Smell & Taste Clinic, Department of Otorhinolaryngology, "Technische Universität Dresden," Fetscherstraße, Dresden, Germany
| | - A Fournel
- CNRS, UMR5292, Lyon Neuroscience Research Center, University Lyon, France
| | - K Albertowski
- Department of Child and Adolescent Psychiatry and Psychotherapy, "Technische Universität Dresden," Fetscherstraße, Dresden, Germany
| | - V Roessner
- Department of Child and Adolescent Psychiatry and Psychotherapy, "Technische Universität Dresden," Fetscherstraße, Dresden, Germany
| | - J Gerber
- Department of Neuroradiology, "Technische Universität Dresden," Fetscherstraße, Dresden, Germany
| | - C Hummel
- Smell & Taste Clinic, Department of Otorhinolaryngology, "Technische Universität Dresden," Fetscherstraße, Dresden, Germany
| | - T Hummel
- Smell & Taste Clinic, Department of Otorhinolaryngology, "Technische Universität Dresden," Fetscherstraße, Dresden, Germany
| | - M Bensafi
- CNRS, UMR5292, Lyon Neuroscience Research Center, University Lyon, France
| |
Collapse
|
34
|
Georgiopoulos C, Witt ST, Haller S, Dizdar N, Zachrisson H, Engström M, Larsson EM. Olfactory fMRI: Implications of Stimulation Length and Repetition Time. Chem Senses 2019; 43:389-398. [PMID: 29726890 DOI: 10.1093/chemse/bjy025] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Studying olfaction with functional magnetic resonance imaging (fMRI) poses various methodological challenges. This study aimed to investigate the effects of stimulation length and repetition time (TR) on the activation pattern of 4 olfactory brain regions: the anterior and the posterior piriform cortex, the orbitofrontal cortex, and the insula. Twenty-two healthy participants with normal olfaction were examined with fMRI, with 2 stimulation lengths (6 s and 15 s) and 2 TRs (0.901 s and 1.34 s). Data were analyzed using General Linear Model (GLM), Tensorial Independent Component Analysis (TICA), and by plotting the event-related time course of brain activation in the 4 olfactory regions of interest. The statistical analysis of the time courses revealed that short TR was associated with more pronounced signal increase and short stimulation was associated with shorter time to peak signal. Additionally, both long stimulation and short TR were associated with oscillatory time courses, whereas both short stimulation and short TR resulted in more typical time courses. GLM analysis showed that the combination of short stimulation and short TR could result in visually larger activation within these olfactory areas. TICA validated that the tested paradigm was spatially and temporally associated with a functionally connected network that included all 4 olfactory regions. In conclusion, the combination of short stimulation and short TR is associated with higher signal increase and shorter time to peak, making it more amenable to standard GLM-type analyses than long stimulation and long TR, and it should, thus, be preferable for olfactory fMRI.
Collapse
Affiliation(s)
- Charalampos Georgiopoulos
- Department of Radiology and Department of Medical and Health Sciences, Linköping University, Röntgenkliniken, Universitetssjukhuset, Linköping, Sweden.,Center for Medical Image Science and Visualization (CMIV), Linköping University, University Hospital, Linköping, Sweden
| | - Suzanne T Witt
- Center for Medical Image Science and Visualization (CMIV), Linköping University, University Hospital, Linköping, Sweden
| | - Sven Haller
- Affidea CDRC Centre de Diagnostic Radiologique de Carouge SA, clos de la Fonderie, Geneva, Switzerland.,Department of Surgical Sciences/Radiology, Uppsala University, Akademiska sjukhuset Uppsala, Sweden
| | - Nil Dizdar
- Department of Neurology and Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Helene Zachrisson
- Department of Clinical Physiology and Department of Medical and Health Sciences, Linköping University, Linköping, Sweden
| | - Maria Engström
- Center for Medical Image Science and Visualization (CMIV), Linköping University, University Hospital, Linköping, Sweden.,Department of Medical and Health Sciences, Linköping University, Sandbäcksgatan, Linköping, Sweden
| | - Elna-Marie Larsson
- Department of Surgical Sciences/Radiology, Uppsala University, Akademiska sjukhuset Uppsala, Sweden
| |
Collapse
|
35
|
Beyeler M, Rounds EL, Carlson KD, Dutt N, Krichmar JL. Neural correlates of sparse coding and dimensionality reduction. PLoS Comput Biol 2019; 15:e1006908. [PMID: 31246948 PMCID: PMC6597036 DOI: 10.1371/journal.pcbi.1006908] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Supported by recent computational studies, there is increasing evidence that a wide range of neuronal responses can be understood as an emergent property of nonnegative sparse coding (NSC), an efficient population coding scheme based on dimensionality reduction and sparsity constraints. We review evidence that NSC might be employed by sensory areas to efficiently encode external stimulus spaces, by some associative areas to conjunctively represent multiple behaviorally relevant variables, and possibly by the basal ganglia to coordinate movement. In addition, NSC might provide a useful theoretical framework under which to understand the often complex and nonintuitive response properties of neurons in other brain areas. Although NSC might not apply to all brain areas (for example, motor or executive function areas) the success of NSC-based models, especially in sensory areas, warrants further investigation for neural correlates in other regions.
Collapse
Affiliation(s)
- Michael Beyeler
- Department of Psychology, University of Washington, Seattle, Washington, United States of America
- Institute for Neuroengineering, University of Washington, Seattle, Washington, United States of America
- eScience Institute, University of Washington, Seattle, Washington, United States of America
- Department of Computer Science, University of California, Irvine, California, United States of America
| | - Emily L. Rounds
- Department of Cognitive Sciences, University of California, Irvine, California, United States of America
| | - Kristofor D. Carlson
- Department of Cognitive Sciences, University of California, Irvine, California, United States of America
- Sandia National Laboratories, Albuquerque, New Mexico, United States of America
| | - Nikil Dutt
- Department of Computer Science, University of California, Irvine, California, United States of America
- Department of Cognitive Sciences, University of California, Irvine, California, United States of America
| | - Jeffrey L. Krichmar
- Department of Computer Science, University of California, Irvine, California, United States of America
- Department of Cognitive Sciences, University of California, Irvine, California, United States of America
| |
Collapse
|
36
|
Courtiol E, Buonviso N, Litaudon P. Odorant features differentially modulate beta/gamma oscillatory patterns in anterior versus posterior piriform cortex. Neuroscience 2019; 409:26-34. [PMID: 31022464 DOI: 10.1016/j.neuroscience.2019.04.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 04/09/2019] [Accepted: 04/11/2019] [Indexed: 12/01/2022]
Abstract
Oscillatory activity is a prominent characteristic of the olfactory system. We previously demonstrated that beta and gamma oscillations occurrence in the olfactory bulb (OB) is modulated by the physical properties of the odorant. However, it remains unknown whether such odor-related modulation of oscillatory patterns is maintained in the piriform cortex (PC) and whether those patterns are similar between the anterior PC (aPC) and posterior PC (pPC). The present study was designed to analyze how different odorant molecular features can affect the local field potential (LFP) oscillatory signals in both the aPC and the pPC in anesthetized rats. As reported in the OB, three oscillatory patterns were observed: standard pattern (gamma + beta), gamma-only and beta-only patterns. These patterns occurred with significantly different probabilities in the two PC areas. We observed that odor identity has a strong influence on the probability of occurrence of LFP beta and gamma oscillatory activity in the aPC. Thus, some odor coding mechanisms observed in the OB are retained in the aPC. By contrast, probability of occurrence of different oscillatory patterns is homogeneous in the pPC with beta-only pattern being the most prevalent one for all the different odor families. Overall, our results confirmed the functional heterogeneity of the PC with its anterior part tightly coupled with the OB and mainly encoding odorant features whereas its posterior part activity is not correlated with odorant features but probably more involved in associative and multi-sensory encoding functions.
Collapse
Affiliation(s)
- Emmanuelle Courtiol
- Lyon Neuroscience Research Center, "Olfaction: from coding to memory" Team; CNRS UMR5292 - Inserm U1028 - Université Lyon 1-Université de Lyon, Centre Hospitalier Le Vinatier - Bâtiment 462 - Neurocampus, 95 boulevard Pinel, 69675 Bron Cedex, France
| | - Nathalie Buonviso
- Lyon Neuroscience Research Center, "Olfaction: from coding to memory" Team; CNRS UMR5292 - Inserm U1028 - Université Lyon 1-Université de Lyon, Centre Hospitalier Le Vinatier - Bâtiment 462 - Neurocampus, 95 boulevard Pinel, 69675 Bron Cedex, France
| | - Philippe Litaudon
- Lyon Neuroscience Research Center, "Olfaction: from coding to memory" Team; CNRS UMR5292 - Inserm U1028 - Université Lyon 1-Université de Lyon, Centre Hospitalier Le Vinatier - Bâtiment 462 - Neurocampus, 95 boulevard Pinel, 69675 Bron Cedex, France.
| |
Collapse
|
37
|
Muttray A, Gosepath J, Schmall F, Brieger J, Mayer-Popken O, Melia M, Letzel S. An acute exposure to ozone impairs human olfactory functioning. ENVIRONMENTAL RESEARCH 2018; 167:42-50. [PMID: 30007872 DOI: 10.1016/j.envres.2018.07.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 06/11/2018] [Accepted: 07/03/2018] [Indexed: 06/08/2023]
Abstract
INTRODUCTION Ozone is a ubiquitous and irritant gas. We questioned whether an acute exposure to 0.2 ppm ozone impaired olfactory functioning. METHODS Healthy, normosmic subjects were exposed according to a parallel group design either to 0.2 ppm ozone (n = 15) or to sham (n = 13) in an exposure chamber for two hours. Possible irritating effects were assessed by questionnaire (range 0-5). The detection threshold of n-butanol was measured with the Sniffin' Sticks test before and after exposure. Olfactory thresholds were logarithmized and a two-way analysis of variance (ANOVA) with repeated measurements was carried out to test the effects of exposure (ozone vs. sham) and time (before vs. after exposure). Additionally, nasal secretions were taken at a preliminary examination and after exposure to determine interleukins 1ß and 8. RESULTS No irritating effects to the upper airways were observed. In the ozone group, the median score for cough increased from 0 to 2 at the end of exposure (sham group 0 and 0, respectively, p < 0.001). The ANOVA showed a main effect for ozone exposure (F (1, 26) = 27.6, p = 0.0002), indicating higher olfactory thresholds in the ozone group. Concentrations of interleukins in nasal secretions did not increase following ozone exposure. CONCLUSIONS This study shows a clear impairment of olfactory functioning following an acute exposure to 0.2 ppm ozone.
Collapse
Affiliation(s)
- Axel Muttray
- Institute of Occupational, Social and Environmental Medicine, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, D-55131 Mainz, Germany.
| | - Jan Gosepath
- Department of Otolaryngology of the University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, D-55131 Mainz, Germany
| | - Florian Schmall
- Institute of Occupational, Social and Environmental Medicine, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, D-55131 Mainz, Germany; Department of Otolaryngology of the University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, D-55131 Mainz, Germany
| | - Jürgen Brieger
- Department of Otolaryngology of the University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, D-55131 Mainz, Germany
| | - Otfried Mayer-Popken
- Institute of Occupational, Social and Environmental Medicine, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, D-55131 Mainz, Germany
| | - Michael Melia
- Institute of Occupational, Social and Environmental Medicine, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, D-55131 Mainz, Germany
| | - Stephan Letzel
- Institute of Occupational, Social and Environmental Medicine, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, D-55131 Mainz, Germany
| |
Collapse
|
38
|
Whitcroft KL, Fischer J, Han P, Raue C, Bensafi M, Gudziol V, Andrews P, Hummel T. Structural Plasticity of the Primary and Secondary Olfactory cortices: Increased Gray Matter Volume Following Surgical Treatment for Chronic Rhinosinusitis. Neuroscience 2018; 395:22-34. [PMID: 30326289 DOI: 10.1016/j.neuroscience.2018.10.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 10/07/2018] [Accepted: 10/08/2018] [Indexed: 01/19/2023]
Abstract
Functional plasticity of the adult brain is well established. Recently, the structural counterpart to such plasticity has been suggested by neuroimaging studies showing experience-dependent differences in gray matter (GM) volumes. Within the primary and secondary olfactory cortices, reduced GM volumes have been demonstrated in patients with olfactory loss. However, these cross-sectional studies do not provide causal evidence for GM volume change, and thereby structural plasticity. Disorders of the peripheral olfactory system, such as chronic rhinosinusitis (CRS), provide an ideal model to study GM structural plasticity, given that patients may experience long periods of olfactory impairment, followed by near complete recovery with treatment. We therefore performed a prospective longitudinal study in patients undergoing surgical treatment for CRS. We used voxel-based morphometry (VBM) to investigate GM volume change in 12 patients (M:F = 7:5; 47.2 ± 14.9 years), 3 months post-op. There was a significant improvement in olfactory function according to birhinal psychophysical testing. We performed a voxel-wise region of interest analysis, with significance corrected for number of regions (p < 0.0036corr). We found significantly increased post-operative GM volumes within the primary (left piriform cortex, right amygdala) and secondary (right orbitofrontal cortex, caudate nucleus, hippocampal-parahippocampal complex and bilateral temporal poles) olfactory networks, and decreased GM volumes within the secondary network only (left caudate nucleus and temporal pole, bilateral hippocampal-parahippocampal complex). As a control measure, we assessed GM change within V1, S1 and A1, where there were no suprathreshold voxels. To our knowledge, this is the first study to demonstrate GM structural plasticity within the primary and secondary olfactory cortices, following restoration of olfaction.
Collapse
Affiliation(s)
- K L Whitcroft
- Interdisciplinary Smell and Taste Lab, TU Dresden, Dresden, Germany; UCL Ear Institute, University College London, UK; Centre for the Study of the Senses, Institute of Philosophy, School of Advanced Study, UK; Royal National Throat Nose and Ear Hospital, Department of Rhinology and Facial Plastic Surgery, London, UK.
| | - J Fischer
- Interdisciplinary Smell and Taste Lab, TU Dresden, Dresden, Germany
| | - P Han
- Interdisciplinary Smell and Taste Lab, TU Dresden, Dresden, Germany
| | - C Raue
- Department of Neuroradiology, TU Dresden, Dresden, Germany
| | - M Bensafi
- Department of Psychology, University of Lyon I, Lyon, France
| | - V Gudziol
- Interdisciplinary Smell and Taste Lab, TU Dresden, Dresden, Germany
| | - P Andrews
- UCL Ear Institute, University College London, UK; Royal National Throat Nose and Ear Hospital, Department of Rhinology and Facial Plastic Surgery, London, UK
| | - T Hummel
- Interdisciplinary Smell and Taste Lab, TU Dresden, Dresden, Germany
| |
Collapse
|
39
|
Aguilar Martínez N, Aguado Carrillo G, Saucedo Alvarado P, Mendoza García C, Velasco Monroy A, Velasco Campos F. Clinical importance of olfactory function in neurodegenerative diseases. REVISTA MÉDICA DEL HOSPITAL GENERAL DE MÉXICO 2018. [DOI: 10.1016/j.hgmx.2017.05.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
|
40
|
Olfactory Dysfunction in CNS Neuroimmunological Disorders: a Review. Mol Neurobiol 2018; 56:3714-3721. [PMID: 30191380 DOI: 10.1007/s12035-018-1341-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 08/31/2018] [Indexed: 12/21/2022]
Abstract
Olfactory dysfunction is deeply associated with quality of human life in the aging population. Olfactory dysfunction is an occasional presymptomatic sign of neuroimmunological multiple sclerosis, neuromyelitis optica, and systemic lupus erythematosus. Olfaction is initially processed by olfactory receptor cells that capture odor molecules, and the signals are transmitted to the glomeruli in the olfactory bulbs via olfactory nerves and processed in the primary olfactory cortex in the brain. Damage to either the olfactory receptor cells or the olfactory bulb and primary olfactory cortex may influence olfactory functioning. A close link between neuroimmunological disorders and olfactory dysfunction has been reported in patients and animal models. This review summarizes the literature data concerning olfactory dysfunction in autoimmune diseases including multiple sclerosis, neuromyelitis optica, and systemic lupus erythematosus; animal models thereof; and inflammation in the olfactory bulb.
Collapse
|
41
|
Differential inhibition of pyramidal cells and inhibitory interneurons along the rostrocaudal axis of anterior piriform cortex. Proc Natl Acad Sci U S A 2018; 115:E8067-E8076. [PMID: 30087186 DOI: 10.1073/pnas.1802428115] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The spatial representation of stimuli in sensory neocortices provides a scaffold for elucidating circuit mechanisms underlying sensory processing. However, the anterior piriform cortex (APC) lacks topology for odor identity as well as afferent and intracortical excitation. Consequently, olfactory processing is considered homogenous along the APC rostral-caudal (RC) axis. We recorded excitatory and inhibitory neurons in APC while optogenetically activating GABAergic interneurons along the RC axis. In contrast to excitation, we find opposing, spatially asymmetric inhibition onto pyramidal cells (PCs) and interneurons. PCs are strongly inhibited by caudal stimulation sites, whereas interneurons are strongly inhibited by rostral sites. At least two mechanisms underlie spatial asymmetries. Enhanced caudal inhibition of PCs is due to increased synaptic strength, whereas rostrally biased inhibition of interneurons is mediated by increased somatostatin-interneuron density. Altogether, we show differences in rostral and caudal inhibitory circuits in APC that may underlie spatial variation in odor processing along the RC axis.
Collapse
|
42
|
Wacker D, Ludwig M. The role of vasopressin in olfactory and visual processing. Cell Tissue Res 2018; 375:201-215. [PMID: 29951699 PMCID: PMC6335376 DOI: 10.1007/s00441-018-2867-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Accepted: 05/31/2018] [Indexed: 12/23/2022]
Abstract
Neural vasopressin is a potent modulator of behaviour in vertebrates. It acts at both sensory processing regions and within larger regulatory networks to mediate changes in social recognition, affiliation, aggression, communication and other social behaviours. There are multiple populations of vasopressin neurons within the brain, including groups in olfactory and visual processing regions. Some of these vasopressin neurons, such as those in the main and accessory olfactory bulbs, anterior olfactory nucleus, piriform cortex and retina, were recently identified using an enhanced green fluorescent protein-vasopressin (eGFP-VP) transgenic rat. Based on the interconnectivity of vasopressin-producing and sensitive brain areas and in consideration of autocrine, paracrine and neurohormone-like actions associated with somato-dendritic release, we discuss how these different neuronal populations may interact to impact behaviour.
Collapse
Affiliation(s)
- Douglas Wacker
- School of STEM (Division of Biological Sciences), University of Washington Bothell, Bothell, WA, USA.
| | - Mike Ludwig
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,Centre for Neuroendocrinology, University of Pretoria, Pretoria, South Africa
| |
Collapse
|
43
|
Kronenbuerger M, Belenghi P, Ilgner J, Freiherr J, Hummel T, Neuner I. Olfactory functioning in adults with Tourette syndrome. PLoS One 2018; 13:e0197598. [PMID: 29874283 PMCID: PMC5991349 DOI: 10.1371/journal.pone.0197598] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 05/04/2018] [Indexed: 01/19/2023] Open
Abstract
Tourette syndrome is a chronic tic disorder characterized by motor and vocal tics. Comorbidities such as attention deficit hyperactivity disorder and obsessive compulsive disorder can be found. The overlap between neuroanatomical regions and neurotransmitter systems in the olfactory system and the pathophysiology of Tourette syndrome let us hypothesize altered olfactory performance in Tourette syndrome. The main objective of this study was to systematically assess olfactory functioning in subjects with Tourette syndrome and to compare it to healthy controls. We assessed 28 adults with Tourette syndrome (age 33.1±9.4 years, disease duration 23.7±9.7 years) and 28 healthy controls (age 32.9±9.0 years) matched in regard to age, sex, education and smoking habits. The “Sniffin Sticks” test battery was applied to assess odor threshold, discrimination, and identification. Additionally, the combined score of the odor threshold test, the odor discrimination test and the odor identification test of the “Sniffin Sticks” test battery was calculated. Although it was not the primary aim of this study, we assessed whether tics and comorbidity could contribute to olfactory alterations in adults with Tourette syndrome. Therefore, clinical scores were used to assess severity of tics and co-morbidity such as attention deficit hyperactivity disorder, obsessive compulsive disorder, anxiety and depression in subjects with Tourette syndrome. Pathology of the nasal cavities was excluded with rhinoendoscopy. Independent sample t-tests were applied to compare performance in olfactory tests. In the case of statistically significant differences (critical p-value: 0.05), multiple linear regression analysis was carried out to explore whether tic severity, social impairment, co-morbidity or medical treatment had an impact on the differences found. Descriptive values are reported as mean ± standard deviation. Tourette syndrome subjects showed lower combined scores (Tourette syndrome subjects 31.9 ± 5.1 versus healthy controls 35.0 ± 3.1; p = 0.007), odor identification scores (Tourette syndrome subjects 12.4 ± 2.0 versus healthy controls 13.7 ± 1.4; p = 0.008) and odor discrimination scores (Tourette syndrome subjects 12.1 ± 2.1 versus healthy controls 13.2 ± 1.6; p = 0.041) in comparison to healthy subjects, while there was no difference in odor threshold (Tourette syndrome subjects 7.3 ± 2.7 versus healthy controls 8.1 ± 2.2; p = 0.22). Seven out of 28 Tourette syndrome subjects (25%) scored in the range of the age- and sex-dependent combined score for hyposmia, while two of 28 healthy controls (7%) had a similar low combined score. None of the participants were found to have functional anosmia. Multiple linear regression analyses suggest that social impairment may a predictor for low combined score and odor identification score in Tourette syndrome subjects (p = 0.003). Compared to healthy controls, altered olfaction in adults with Tourette syndrome was found in this study. Normal odor threshold level but lower scores at tasks involving supra-threshold odor concentrations point towards a central-nervous alteration in the processing of olfactory information in Tourette syndrome.
Collapse
Affiliation(s)
- Martin Kronenbuerger
- Department of Neurology, Johns Hopkins University, Baltimore, Maryland, United States of America
- Department of Neurology, RWTH Aachen University, Aachen, Germany
- Department of Neurology, University of Greifswald, Greifswald, Germany
- * E-mail:
| | - Patrizia Belenghi
- Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, Aachen, Germany
| | - Justus Ilgner
- Department of Otorhinolaryngology and Plastic Head and Neck Surgery, RWTH Aachen University, Aachen, Germany
| | - Jessica Freiherr
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, Aachen, Germany
| | - Thomas Hummel
- Department of Otorhinolaryngology, TU Dresden, Dresden, Germany
| | - Irene Neuner
- Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, Aachen, Germany
- JARA—Translational Brain Medicine, Aachen, Germany
- Institute of Neuroscience and Medicine 4, Forschungszentrum, Jülich, Germany
| |
Collapse
|
44
|
Indistinguishable odour enantiomers: Differences between peripheral and central-nervous electrophysiological responses. Sci Rep 2017; 7:8978. [PMID: 28827647 PMCID: PMC5566401 DOI: 10.1038/s41598-017-09594-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 07/21/2017] [Indexed: 11/09/2022] Open
Abstract
The ability of humans to discriminate enantiomeric odour pairs is substance -specific. Current literature suggests that psychophysical discrimination of odour enantiomers mainly depends on the peripheral processing at the level of the olfactory sensory neurons (OSN). To study the influence of central processing in discrimination, we investigated differences in the electrophysiological responses to psychophysically indistinguishable (+)- and (-)- rose oxide enantiomers at peripheral and central-nervous levels in humans. We recorded the electro-olfactogram (EOG) from the olfactory epithelium and the EEG-derived olfactory event-related potentials (OERP). Results from a psychophysical three alternative forced choice test indicated indistinguishability of the two odour enantiomers. In a total of 19 young participants EOG could be recorded in 74 and OERP in 95% of subjects. Significantly different EOG amplitudes and latencies were recorded in response to the 2 stimuli. However, no such differences in amplitude or latency emerged for the OERP. In conclusion, although the pair of enantiomer could be discriminated at a peripheral level this did not lead to a central-nervous/cognitive differentiation of the two stimuli.
Collapse
|
45
|
Jiang H, Schuele S, Rosenow J, Zelano C, Parvizi J, Tao JX, Wu S, Gottfried JA. Theta Oscillations Rapidly Convey Odor-Specific Content in Human Piriform Cortex. Neuron 2017; 94:207-219.e4. [PMID: 28384472 DOI: 10.1016/j.neuron.2017.03.021] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 01/26/2017] [Accepted: 03/09/2017] [Indexed: 12/21/2022]
Abstract
Olfactory oscillations are pervasive throughout vertebrate and invertebrate nervous systems. Such observations have long implied that rhythmic activity patterns play a fundamental role in odor coding. Using intracranial EEG recordings from rare patients with medically resistant epilepsy, we find that theta oscillations are a distinct electrophysiological signature of olfactory processing in the human brain. Across seven patients, odor stimulation enhanced theta power in human piriform cortex, with robust effects at the level of single trials. Importantly, classification analysis revealed that piriform oscillatory activity conveys olfactory-specific information that can be decoded within 110-518 ms of a sniff, and maximally within the theta frequency band. This temporal window was also associated with increased theta-specific phase coupling between piriform cortex and hippocampus. Together these findings suggest that human piriform cortex has access to olfactory content in the time-frequency domain and can utilize these signals to rapidly differentiate odor stimuli.
Collapse
Affiliation(s)
- Heidi Jiang
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.
| | - Stephan Schuele
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Joshua Rosenow
- Department of Neurosurgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Christina Zelano
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Josef Parvizi
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA 94305, USA
| | - James X Tao
- Department of Neurology, University of Chicago, Chicago, IL 60637, USA
| | - Shasha Wu
- Department of Neurology, University of Chicago, Chicago, IL 60637, USA
| | - Jay A Gottfried
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA; Department of Psychology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208, USA.
| |
Collapse
|
46
|
Milardi D, Cacciola A, Calamuneri A, Ghilardi MF, Caminiti F, Cascio F, Andronaco V, Anastasi G, Mormina E, Arrigo A, Bruschetta D, Quartarone A. The Olfactory System Revealed: Non-Invasive Mapping by using Constrained Spherical Deconvolution Tractography in Healthy Humans. Front Neuroanat 2017; 11:32. [PMID: 28443000 PMCID: PMC5385345 DOI: 10.3389/fnana.2017.00032] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Accepted: 03/28/2017] [Indexed: 11/27/2022] Open
Abstract
Although the olfactory sense has always been considered with less interest than the visual, auditive or somatic senses, it does plays a major role in our ordinary life, with important implication in dangerous situations or in social and emotional behaviors. Traditional Diffusion Tensor signal model and related tractography have been used in the past years to reconstruct the cranial nerves, including the olfactory nerve (ON). However, no supplementary information with regard to the pathways of the olfactory network have been provided. Here, by using the more advanced Constrained Spherical Deconvolution (CSD) diffusion model, we show for the first time in vivo and non-invasively that, in healthy humans, the olfactory system has a widely distributed anatomical network to several cortical regions as well as to many subcortical structures. Although the present study focuses on an healthy sample size, a similar approach could be applied in the near future to gain important insights with regard to the early involvement of olfaction in several neurodegenerative disorders.
Collapse
Affiliation(s)
- Demetrio Milardi
- Centro Neurolesi Bonino Pulejo (IRCCS)Messina, Italy.,Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of MessinaMessina, Italy
| | | | - Alessandro Calamuneri
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of MessinaMessina, Italy
| | - Maria F Ghilardi
- Sophie Davis School for Biomedical Education, City College New York (CCNY), The City University of New York (CUNY)New York, NY, USA.,The Fresco Institute for Parkinson's and Movement Disorders, NYU Langone Medical Center, New York UniversityNew York, NY, USA
| | | | - Filippo Cascio
- Department of Otorhinolaryngology, Papardo HospitalMessina, Italy
| | | | - Giuseppe Anastasi
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of MessinaMessina, Italy
| | - Enricomaria Mormina
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of MessinaMessina, Italy
| | - Alessandro Arrigo
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of MessinaMessina, Italy
| | - Daniele Bruschetta
- Centro Neurolesi Bonino Pulejo (IRCCS)Messina, Italy.,Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of MessinaMessina, Italy
| | - Angelo Quartarone
- Centro Neurolesi Bonino Pulejo (IRCCS)Messina, Italy.,Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of MessinaMessina, Italy
| |
Collapse
|
47
|
Han P, Whitcroft KL, Fischer J, Gerber J, Cuevas M, Andrews P, Hummel T. Olfactory brain gray matter volume reduction in patients with chronic rhinosinusitis. Int Forum Allergy Rhinol 2017; 7:551-556. [DOI: 10.1002/alr.21922] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 01/03/2017] [Accepted: 01/10/2017] [Indexed: 01/19/2023]
Affiliation(s)
- Pengfei Han
- Smell & Taste Clinic, Department of Otorhinolaryngology; Technische Universität Dresden; Dresden Germany
- Department of Neuropediatrics; University Hospital Carl Gustav Carus; Dresden Germany
| | - Katherine L. Whitcroft
- Smell & Taste Clinic, Department of Otorhinolaryngology; Technische Universität Dresden; Dresden Germany
- UCL Ear Institute; London UK
| | - Jessica Fischer
- Smell & Taste Clinic, Department of Otorhinolaryngology; Technische Universität Dresden; Dresden Germany
| | - Johannes Gerber
- Department of Neuroradiology; Technische Universität Dresden; Dresden Germany
| | - Mandy Cuevas
- Smell & Taste Clinic, Department of Otorhinolaryngology; Technische Universität Dresden; Dresden Germany
| | | | - Thomas Hummel
- Smell & Taste Clinic, Department of Otorhinolaryngology; Technische Universität Dresden; Dresden Germany
| |
Collapse
|
48
|
Silveira-Moriyama L, Glass P, Rajan S, Carvalho R, Reis F, Penatti CAA, Muio V. The Hitchhiker's guide to the rhinencephalon. ARQUIVOS DE NEURO-PSIQUIATRIA 2016; 74:329-36. [PMID: 27097007 DOI: 10.1590/0004-282x20160043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2016] [Accepted: 01/07/2016] [Indexed: 05/11/2023]
Abstract
Pathology of the rhinencephalon has been a subject of interest in the fields of neurodegenerative diseases, trauma, epilepsy and other neurological conditions. Most of what is known about the human rhinencephalon comes from comparative anatomy studies in other mammals and histological studies in primates. Functional imaging studies can provide new and important insight into the function of the rhinencephalon in humans but have limited spatial resolution, limiting its contribution to the study of the anatomy of the human rhinencephalon. In this study we aim to provide a brief and objective review of the anatomy of this important and often overlooked area of the nervous system.
Collapse
Affiliation(s)
| | - Philip Glass
- Faculdade de Ciências Médicas, Universidade Estadual de Campinas, Campinas, SP, Brazil
| | - Suraj Rajan
- The Clinical Neuroscience Institute, Premier Health Miami Valley Hospital, Dayton, OH, USA
| | | | - Fabiano Reis
- Faculdade de Ciências Médicas, Universidade Estadual de Campinas, Campinas, SP, Brazil
| | | | - Valeria Muio
- Universidade Nove de Julho, Sao Paulo, SP, Brazil
| |
Collapse
|
49
|
Distribution and fate of DCX/PSA-NCAM expressing cells in the adult mammalian cortex: A local reservoir for adult cortical neuroplasticity? ACTA ACUST UNITED AC 2016. [DOI: 10.1007/s11515-016-1403-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
50
|
Fournel A, Ferdenzi C, Sezille C, Rouby C, Bensafi M. Multidimensional representation of odors in the human olfactory cortex. Hum Brain Mapp 2016; 37:2161-72. [PMID: 26991044 DOI: 10.1002/hbm.23164] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 02/09/2016] [Accepted: 02/18/2016] [Indexed: 11/09/2022] Open
Abstract
What is known as an odor object is an integrated representation constructed from physical features, and perceptual attributes mainly mediated by the olfactory and trigeminal systems. The aim of the present study was to comprehend how this multidimensional representation is organized, by deciphering how similarities in the physical, olfactory and trigeminal perceptual spaces of odors are represented in the human brain. To achieve this aim, we combined psychophysics, functional MRI and multivariate representational similarity analysis. Participants were asked to smell odors diffused by an fMRI-compatible olfactometer and to rate each smell along olfactory dimensions (pleasantness, intensity, familiarity and edibility) and trigeminal dimensions (irritation, coolness, warmth and pain). An event-related design was implemented, presenting different odorants. Results revealed that (i) pairwise odorant similarities in anterior piriform cortex (PC) activity correlated with pairwise odorant similarities in chemical properties (P < 0.005), (ii) similarities in posterior PC activity correlated with similarities in olfactory perceptual properties (P <0.01), and (iii) similarities in amygdala activity correlated with similarities in trigeminal perceptual properties (P < 0.01). These findings provide new evidence that extraction of physical, olfactory and trigeminal features is based on specific fine processing of similarities between odorous stimuli in a distributed manner in the olfactory system. Hum Brain Mapp 37:2161-2172, 2016. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- A Fournel
- Lyon Neuroscience Research Center, CNRS UMR5292, INSERM U1028, University Lyon, F-69000, France
| | - C Ferdenzi
- Lyon Neuroscience Research Center, CNRS UMR5292, INSERM U1028, University Lyon, F-69000, France
| | - C Sezille
- Lyon Neuroscience Research Center, CNRS UMR5292, INSERM U1028, University Lyon, F-69000, France
| | - C Rouby
- Lyon Neuroscience Research Center, CNRS UMR5292, INSERM U1028, University Lyon, F-69000, France
| | - M Bensafi
- Lyon Neuroscience Research Center, CNRS UMR5292, INSERM U1028, University Lyon, F-69000, France
| |
Collapse
|