1
|
Tort ABL, Laplagne DA, Draguhn A, Gonzalez J. Global coordination of brain activity by the breathing cycle. Nat Rev Neurosci 2025; 26:333-353. [PMID: 40204908 DOI: 10.1038/s41583-025-00920-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/19/2025] [Indexed: 04/11/2025]
Abstract
Neuronal activities that synchronize with the breathing rhythm have been found in humans and a host of mammalian species, not only in brain areas closely related to respiratory control or olfactory coding but also in areas linked to emotional and higher cognitive functions. In parallel, evidence is mounting for modulations of perception and action by the breathing cycle. In this Review, we discuss the extent to which brain activity locks to breathing across areas, levels of organization and brain states, and the physiological origins of this global synchrony. We describe how waves of sensory activity evoked by nasal airflow spread through brain circuits, synchronizing neuronal populations to the breathing cycle and modulating faster oscillations, cell assembly formation and cross-area communication, thereby providing a mechanistic link from breathing to neural coding, emotion and cognition. We argue that, through evolution, the breathing rhythm has come to shape network functions across species.
Collapse
Affiliation(s)
- Adriano B L Tort
- Brain Institute, Federal University of Rio Grande do Norte, Natal, Brazil.
| | - Diego A Laplagne
- Brain Institute, Federal University of Rio Grande do Norte, Natal, Brazil.
| | - Andreas Draguhn
- Institute for Physiology and Pathophysiology, Heidelberg University, Heidelberg, Germany
| | - Joaquin Gonzalez
- Brain Institute, Federal University of Rio Grande do Norte, Natal, Brazil
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
- Neuroscience Institute and Department of Psychiatry, New York University Grossman School of Medicine, New York, NY, USA
| |
Collapse
|
2
|
Zhang L, Geng C, Li S, Tang Q, Liu P, Liu W, Qiu G, Li A, Hu A, Chen F. Anterior piriform cortex dysfunction underlies autism spectrum disorders-related olfactory deficits in Fmr1 conditional deletion mice. Neuropsychopharmacology 2025; 50:798-807. [PMID: 39550469 PMCID: PMC11914248 DOI: 10.1038/s41386-024-02027-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2024] [Revised: 11/01/2024] [Accepted: 11/04/2024] [Indexed: 11/18/2024]
Abstract
Previous studies indicated that ASD-related olfactory dysfunctions are rooted in the piriform cortex. However, the direct evidence supporting a causal link between the dysfunction of the piriform cortex and olfactory disorders in ASD is limited. In the present study, we explored the role of anterior piriform cortex (aPC) in ASD-related olfactory disorders by specifically ablating Fmr1, a leading known monogenic cause for ASD, in the pyramidal neurons. Our data demonstrated that the targeted deletion of Fmr1 in aPC pyramidal neurons was sufficient to induce deficits in olfactory detection. In vivo and in vitro electrophysiological recordings showed that the deletion of Fmr1 increased the activity of pyramidal neurons, exhibiting an enhanced excitatory response and a reduced inhibitory response upon odor stimulation. Furthermore, specific deletion of Fmr1 enhanced the power of beta oscillations during odor stimuli, meanwhile, disturbed excitatory and inhibitory synaptic transmission. The abnormal morphology of pyramidal neurons induced by the deletion of Fmr1 may be responsible for the impaired aPC neuronal function. These findings suggest that dysfunction of the aPC may play a role in olfactory impairments observed in ASD models related to Fmr1 deficiency.
Collapse
Affiliation(s)
- Lingzhi Zhang
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
- The Animal Facility of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, China
| | - Chi Geng
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| | - Shan Li
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| | - Qingnan Tang
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| | - Penglai Liu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| | - Wei Liu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| | - Gaoxue Qiu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| | - Anan Li
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| | - Ankang Hu
- The Animal Facility of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, China.
| | - Fengjiao Chen
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China.
| |
Collapse
|
3
|
Zhou J, Yin Z, Chen Z, Fu H, Li Q, Li S, Zhang Y, Zhang X, Tang D, Li A, Wang D. Essential Role of the Anterior Piriform Cortex in Mediating Social Novelty Output via a Top-Down Circuit. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2025; 12:e2406192. [PMID: 39951247 PMCID: PMC11967784 DOI: 10.1002/advs.202406192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2024] [Revised: 01/09/2025] [Indexed: 04/05/2025]
Abstract
Social novelty is indispensable for a wide range of social behaviors. The medial prefrontal cortex (mPFC), along with other social information hubs, composes the foundational circuitry of social novelty. However, the precise circuit mechanisms that govern social novelty processing remain elusive. The piriform cortex, as the largest olfactory cortex, receives extensive innervation from top-down centers that dictate social behavior. Here, it is shown that the anterior piriform cortex (APC) exhibited an increase in gamma event incidence during social engagement in male mice. In vivo electrophysiology and fiber photometry reveal that APC pyramidal neurons respond more intensely to novel mice than familiar ones. Intriguingly, silencing APC neurons selectively impairs social novelty processing, yet leaves the basic olfactory discrimination capabilities intact. Moreover, the APC inherits social cues from the mPFC and sends feedback projections to the olfactory bulb (OB) to modulate social novelty. These findings unveil the APC's role as extending well beyond olfaction, encompassing a specialized function in social novelty recognition in male mice.
Collapse
Affiliation(s)
- Jingwei Zhou
- Jiangsu Key Laboratory of Brain Disease BioinformationResearch Center for Biochemistry and Molecular BiologyXuzhou Medical UniversityXuzhouJiangsu221004China
- Schools of Life ScienceXuzhou Medical UniversityXuzhouJiangsu221004China
| | - Zhaoyang Yin
- Jiangsu Key Laboratory of Brain Disease BioinformationResearch Center for Biochemistry and Molecular BiologyXuzhou Medical UniversityXuzhouJiangsu221004China
| | - Zhiyun Chen
- Jiangsu Key Laboratory of Brain Disease BioinformationResearch Center for Biochemistry and Molecular BiologyXuzhou Medical UniversityXuzhouJiangsu221004China
| | - Hanyu Fu
- Jiangsu Key Laboratory of Brain Disease BioinformationResearch Center for Biochemistry and Molecular BiologyXuzhou Medical UniversityXuzhouJiangsu221004China
| | - Qun Li
- Jiangsu Key Laboratory of Brain Disease BioinformationResearch Center for Biochemistry and Molecular BiologyXuzhou Medical UniversityXuzhouJiangsu221004China
| | - Shan Li
- Jiangsu Key Laboratory of Brain Disease BioinformationResearch Center for Biochemistry and Molecular BiologyXuzhou Medical UniversityXuzhouJiangsu221004China
| | - Ying Zhang
- Jiangsu Key Laboratory of Brain Disease BioinformationResearch Center for Biochemistry and Molecular BiologyXuzhou Medical UniversityXuzhouJiangsu221004China
| | - Xianzhi Zhang
- Jiangsu Key Laboratory of Brain Disease BioinformationResearch Center for Biochemistry and Molecular BiologyXuzhou Medical UniversityXuzhouJiangsu221004China
| | - Dewei Tang
- Jiangsu Key Laboratory of Brain Disease BioinformationResearch Center for Biochemistry and Molecular BiologyXuzhou Medical UniversityXuzhouJiangsu221004China
| | - Anan Li
- Jiangsu Key Laboratory of Brain Disease BioinformationResearch Center for Biochemistry and Molecular BiologyXuzhou Medical UniversityXuzhouJiangsu221004China
| | - Dejuan Wang
- Jiangsu Key Laboratory of Brain Disease BioinformationResearch Center for Biochemistry and Molecular BiologyXuzhou Medical UniversityXuzhouJiangsu221004China
| |
Collapse
|
4
|
Hu B, Temiz NZ, Chou CN, Rupprecht P, Meissner-Bernard C, Titze B, Chung S, Friedrich RW. Representational learning by optimization of neural manifolds in an olfactory memory network. RESEARCH SQUARE 2025:rs.3.rs-6155477. [PMID: 40195987 PMCID: PMC11975023 DOI: 10.21203/rs.3.rs-6155477/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2025]
Abstract
Cognitive brain functions rely on experience-dependent internal representations of relevant information. Such representations are organized by attractor dynamics or other mechanisms that constrain population activity onto "neural manifolds". Quantitative analyses of representational manifolds are complicated by their potentially complex geometry, particularly in the absence of attractor states. Here we trained juvenile and adult zebrafish in an odor discrimination task and measured neuronal population activity to analyze representations of behaviorally relevant odors in telencephalic area pDp, the homolog of piriform cortex. No obvious signatures of attractor dynamics were detected. However, olfactory discrimination training selectively enhanced the separation of neural manifolds representing task-relevant odors from other representations, consistent with predictions of autoassociative network models endowed with precise synaptic balance. Analytical approaches using the framework of manifold capacity revealed multiple geometrical modifications of representational manifolds that supported the classification of task-relevant sensory information. Manifold capacity predicted odor discrimination across individuals better than other descriptors of population activity, indicating a close link between manifold geometry and behavior. Hence, pDp and possibly related recurrent networks store information in the geometry of representational manifolds, resulting in joint sensory and semantic maps that may support distributed learning processes.
Collapse
Affiliation(s)
- Bo Hu
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland
- University of Basel, 4003 Basel, Switzerland
| | - Nesibe Z. Temiz
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland
- University of Basel, 4003 Basel, Switzerland
| | - Chi-Ning Chou
- Center for Computational Neuroscience, Flatiron Institute, New York, NY, USA
| | - Peter Rupprecht
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland
- Neuroscience Center Zurich, 8057 Zurich, Switzerland
- Brain Research Institute, University of Zurich, 8057 Zurich, Switzerland
| | - Claire Meissner-Bernard
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland
| | - Benjamin Titze
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland
| | - SueYeon Chung
- Center for Computational Neuroscience, Flatiron Institute, New York, NY, USA
- Center for Neural Science, New York University, New York, NY, USA
| | - Rainer W. Friedrich
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland
- University of Basel, 4003 Basel, Switzerland
| |
Collapse
|
5
|
Meissner-Bernard C, Jenkins B, Rupprecht P, Bouldoires EA, Zenke F, Friedrich RW, Frank T. Computational functions of precisely balanced neuronal microcircuits in an olfactory memory network. Cell Rep 2025; 44:115330. [PMID: 39985769 DOI: 10.1016/j.celrep.2025.115330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2024] [Revised: 12/12/2024] [Accepted: 01/28/2025] [Indexed: 02/24/2025] Open
Abstract
Models of balanced autoassociative memory networks predict that specific inhibition is critical to store information in connectivity. To explore these predictions, we characterized and manipulated different subtypes of fast-spiking interneurons in the posterior telencephalic area Dp (pDp) of adult zebrafish, the homolog of the piriform cortex. Modeling of recurrent networks with assemblies showed that a precise balance of excitation and inhibition is important to prevent not only excessive firing rates ("runaway activity") but also the stochastic occurrence of high pattern correlations ("runaway correlations"). Consistent with model predictions, runaway correlations emerged in pDp when synaptic balance was perturbed by optogenetic manipulations of feedback inhibition but not feedforward inhibition. Runaway correlations were driven by sparse subsets of strongly active neurons rather than by a general broadening of tuning curves. These results are consistent with balanced neuronal assemblies in pDp and reveal novel computational functions of inhibitory microcircuits in an autoassociative network.
Collapse
Affiliation(s)
- Claire Meissner-Bernard
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland
| | - Bethan Jenkins
- University of Göttingen, Faculty of Biology and Psychology, 37073 Göttingen, Germany; Olfactory Memory and Behavior Group, European Neuroscience Institute Göttingen - A Joint Initiative of the University Medical Center Göttingen and the Max Planck Institute for Multidisciplinary Sciences, Grisebachstraße 5, 37077 Göttingen, Germany; Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, Göttingen, Germany; Göttingen Campus Institute for Dynamics of Biological Networks, 37073 Göttingen, Germany; Max Planck Institute for Biological Intelligence, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Peter Rupprecht
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland; Laboratory of Neural Circuit Dynamics, Brain Research Institute, University of Zurich, Winterthurerstrasse 190, 8057 Zürich, Switzerland; Neuroscience Center Zurich, University of Zurich, 8006 Zürich, Switzerland
| | - Estelle Arn Bouldoires
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland
| | - Friedemann Zenke
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland; University of Basel, 4003 Basel, Switzerland
| | - Rainer W Friedrich
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland; University of Basel, 4003 Basel, Switzerland.
| | - Thomas Frank
- University of Göttingen, Faculty of Biology and Psychology, 37073 Göttingen, Germany; Olfactory Memory and Behavior Group, European Neuroscience Institute Göttingen - A Joint Initiative of the University Medical Center Göttingen and the Max Planck Institute for Multidisciplinary Sciences, Grisebachstraße 5, 37077 Göttingen, Germany; Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, Göttingen, Germany; Göttingen Campus Institute for Dynamics of Biological Networks, 37073 Göttingen, Germany; Max Planck Institute for Biological Intelligence, Am Klopferspitz 18, 82152 Martinsried, Germany.
| |
Collapse
|
6
|
Belonio KC, Haile ES, Fyke Z, Vivona L, Konanur VR, Tulabandhula T, Zak JD. Amplification of olfactory transduction currents implements sparse stimulus encoding. J Neurosci 2025; 45:e2008242025. [PMID: 40097179 PMCID: PMC12044040 DOI: 10.1523/jneurosci.2008-24.2025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2024] [Revised: 03/08/2025] [Accepted: 03/11/2025] [Indexed: 03/19/2025] Open
Abstract
Sensory systems must perform the dual and opposing tasks of being sensitive to weak stimuli while also maintaining information content in dense and variable sensory landscapes. This occurs in the olfactory system, where OSNs are highly sensitive to low concentrations of odors and maintain discriminability in complex odor environments. How olfactory sensory neurons (OSNs) maintain both sensitivity and sparsity is poorly understood. Here, we investigated whether the calcium-activated chloride channel, TMEM16B, may support these dual roles in OSNs in both male and female mice. We used multiphoton microscopy to image the stimulus-response density of OSNs in the olfactory epithelium. In TMEM16B knockout mice, we found that sensory representations were denser, and the magnitude of OSN responses was increased. Behaviorally, these changes in sensory representations were associated with an increased aversion to the odorant trimethylamine, which switches perceptual valence as its concentration increases, and a decreased efficiency of olfactory-guided navigation. Our results indicate that the calcium-activated chloride channel TMEM16B sparsens sensory representations in the peripheral olfactory system and contributes to efficient integrative olfactory-guided behaviors.Significance Statement Sensory systems must build internal neural representations of stimuli found in the external environment. In the olfactory system, molecules that give rise to the perception of odors are detected by olfactory sensory neurons within the nose. Upon odorant binding to sensory neurons, a biochemical signaling cascade transduces neural signals that other areas of the brain can then read out. A key component of this cascade is the calcium-activated chloride channel TMEM16B. We found that despite its role in amplifying transduction currents in olfactory sensory neurons, TMEM16B paradoxically constrains their output, thereby limiting information transfer to the brain. Our findings also indicate that TMEM16B plays an important role in how animals detect and perceive odors.
Collapse
Affiliation(s)
- Kai Clane Belonio
- Department of Biological Sciences, University of Illinois Chicago, Chicago, Illinois 60607
| | - Eyerusalem S. Haile
- Graduate Program in Biological Sciences, University of Illinois Chicago, Chicago, Illinois 60607
| | - Zach Fyke
- Graduate Program in Neuroscience, University of Illinois Chicago, Chicago, Illinois 60607
| | - Lindsay Vivona
- Graduate Program in Biological Sciences, University of Illinois Chicago, Chicago, Illinois 60607
| | - Vaibhav R. Konanur
- Department of Biological Sciences, University of Illinois Chicago, Chicago, Illinois 60607
| | - Theja Tulabandhula
- Departments of Information and Decision Sciences, University of Illinois Chicago, Chicago, Illinois 60607
| | - Joseph D. Zak
- Department of Biological Sciences, University of Illinois Chicago, Chicago, Illinois 60607
- Psychology, University of Illinois Chicago, Chicago, Illinois 60607
| |
Collapse
|
7
|
Patel H, Garrido Portilla V, Shneidman AV, Movilli J, Alvarenga J, Dupré C, Aizenberg M, Murthy VN, Tropsha A, Aizenberg J. Design Principles From Natural Olfaction for Electronic Noses. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2025; 12:e2412669. [PMID: 39835449 PMCID: PMC11948017 DOI: 10.1002/advs.202412669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2024] [Revised: 11/29/2024] [Indexed: 01/22/2025]
Abstract
Natural olfactory systems possess remarkable sensitivity and precision beyond what is currently achievable by engineered gas sensors. Unlike their artificial counterparts, noses are capable of distinguishing scents associated with mixtures of volatile molecules in complex, typically fluctuating environments and can adapt to changes. This perspective examines the multifaceted biological principles that provide olfactory systems their discriminatory prowess, and how these ideas can be ported to the design of electronic noses for substantial improvements in performance across metrics such as sensitivity and ability to speciate chemical mixtures. The topics examined herein include the fluid dynamics of odorants in natural channels; specificity and kinetics of odorant interactions with olfactory receptors and mucus linings; complex signal processing that spatiotemporally encodes physicochemical properties of odorants; active sampling techniques, like biological sniffing and nose repositioning; biological priming; and molecular chaperoning. Each of these components of natural olfactory systems are systmatically investigated, as to how they have been or can be applied to electronic noses. While not all artificial sensors can employ these strategies simultaneously, integrating a subset of bioinspired principles can address issues like sensitivity, drift, and poor selectivity, offering advancements in many sectors such as environmental monitoring, industrial safety, and disease diagnostics.
Collapse
Affiliation(s)
- Haritosh Patel
- Harvard John A. Paulson School of Engineering and Applied SciencesHarvard UniversityBostonMA02134USA
| | - Vicente Garrido Portilla
- Harvard John A. Paulson School of Engineering and Applied SciencesHarvard UniversityBostonMA02134USA
| | - Anna V. Shneidman
- Harvard John A. Paulson School of Engineering and Applied SciencesHarvard UniversityBostonMA02134USA
| | - Jacopo Movilli
- Harvard John A. Paulson School of Engineering and Applied SciencesHarvard UniversityBostonMA02134USA
- Department of Chemical SciencesUniversity of PadovaPadova35131Italy
| | - Jack Alvarenga
- Harvard John A. Paulson School of Engineering and Applied SciencesHarvard UniversityBostonMA02134USA
| | - Christophe Dupré
- Department of Molecular & Cellular BiologyHarvard UniversityCambridgeMA02138USA
| | - Michael Aizenberg
- Harvard John A. Paulson School of Engineering and Applied SciencesHarvard UniversityBostonMA02134USA
| | - Venkatesh N. Murthy
- Department of Molecular & Cellular BiologyHarvard UniversityCambridgeMA02138USA
- Center for Brain ScienceHarvard UniversityCambridgeMA02138USA
- Kempner InstituteHarvard UniversityBostonMA02134USA
| | - Alexander Tropsha
- Department of ChemistryThe University of North Carolina at Chapel HillChapel HillNC27516USA
| | - Joanna Aizenberg
- Harvard John A. Paulson School of Engineering and Applied SciencesHarvard UniversityBostonMA02134USA
- Department of Chemistry and Chemical BiologyHarvard UniversityCambridgeMA02138USA
| |
Collapse
|
8
|
Zhao Q, Li Z, Zhang K, Deng X, Wang G, Ye Z, Liu M, Chen J, Chen S, Ye X, Cheng H. Revealing the off-flavors in hydro-distilled essential oils of sweet orange (Citrus sinensis) by flavoromics strategy and computational simulation. Food Chem 2025; 465:141990. [PMID: 39546993 DOI: 10.1016/j.foodchem.2024.141990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2024] [Revised: 10/23/2024] [Accepted: 11/08/2024] [Indexed: 11/17/2024]
Abstract
Citrus essential oils (EOs) are renowned for their aroma, but thermal extraction methods can introduce undesirable cooking and pungent odors. The specific compounds responsible for these off-flavors and their perception mechanisms remain unclear. This study investigated the flavor differences between cold pressing (CP) and hydro-distilled (HD) extracted essential oils from sweet oranges (SEOs) using flavoromics strategy. The results indicated that increased levels of alcohol compounds, particularly terpinen-4-ol, β-citronellol, geraniol, trans-carveol, and α-terpineol, were primarily responsible for the off-flavors in HD-extracted SEOs. Furthermore, molecular docking and dynamics simulations revealed that off-flavor compounds bind to olfactory receptors through hydrogen bonding and hydrophobic interactions, inducing slight structural and conformational changes that facilitate odor recognition and activate downstream signaling events. This study offers crucial insights into the mechanisms underlying off-flavor development in citrus EOs, providing valuable knowledge for optimizing extraction methods, controlling SEOs quality, and advancing flavor science.
Collapse
Affiliation(s)
- Qian Zhao
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Research Center of Intelligent Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang International Scientific and Technological Cooperation Base of Health Food Manufacturing and Quality Control, Zhejiang University, Hangzhou 310058, PR China; Innovation Center of Yangtze River Delta, Zhejiang University, Jiaxing 314102, PR China
| | - Zhongxin Li
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Research Center of Intelligent Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang International Scientific and Technological Cooperation Base of Health Food Manufacturing and Quality Control, Zhejiang University, Hangzhou 310058, PR China
| | - Keer Zhang
- Key Laboratory of Specialty Agri-product Quality and Hazard Controlling Technology of Zhejiang Province, College of Life Sciences, Jiliang University, Hangzhou 310018, PR China
| | - Xinping Deng
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Research Center of Intelligent Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang International Scientific and Technological Cooperation Base of Health Food Manufacturing and Quality Control, Zhejiang University, Hangzhou 310058, PR China; Innovation Center of Yangtze River Delta, Zhejiang University, Jiaxing 314102, PR China
| | - Guangnan Wang
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Research Center of Intelligent Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang International Scientific and Technological Cooperation Base of Health Food Manufacturing and Quality Control, Zhejiang University, Hangzhou 310058, PR China; Innovation Center of Yangtze River Delta, Zhejiang University, Jiaxing 314102, PR China
| | - Zhiyue Ye
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Research Center of Intelligent Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang International Scientific and Technological Cooperation Base of Health Food Manufacturing and Quality Control, Zhejiang University, Hangzhou 310058, PR China; Innovation Center of Yangtze River Delta, Zhejiang University, Jiaxing 314102, PR China
| | - Mingqi Liu
- Key Laboratory of Specialty Agri-product Quality and Hazard Controlling Technology of Zhejiang Province, College of Life Sciences, Jiliang University, Hangzhou 310018, PR China
| | - Jianle Chen
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Research Center of Intelligent Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang International Scientific and Technological Cooperation Base of Health Food Manufacturing and Quality Control, Zhejiang University, Hangzhou 310058, PR China; Ningbo Innovation Center, Zhejiang University, Ningbo 315100, PR China; Zhejiang University Zhongyuan Institute, Zhengzhou 450000, PR China
| | - Shiguo Chen
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Research Center of Intelligent Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang International Scientific and Technological Cooperation Base of Health Food Manufacturing and Quality Control, Zhejiang University, Hangzhou 310058, PR China; Innovation Center of Yangtze River Delta, Zhejiang University, Jiaxing 314102, PR China; Ningbo Innovation Center, Zhejiang University, Ningbo 315100, PR China; Zhejiang University Zhongyuan Institute, Zhengzhou 450000, PR China
| | - Xingqian Ye
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Research Center of Intelligent Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang International Scientific and Technological Cooperation Base of Health Food Manufacturing and Quality Control, Zhejiang University, Hangzhou 310058, PR China; Ningbo Innovation Center, Zhejiang University, Ningbo 315100, PR China; Zhejiang University Zhongyuan Institute, Zhengzhou 450000, PR China
| | - Huan Cheng
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Research Center of Intelligent Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang International Scientific and Technological Cooperation Base of Health Food Manufacturing and Quality Control, Zhejiang University, Hangzhou 310058, PR China; Ningbo Innovation Center, Zhejiang University, Ningbo 315100, PR China; Zhejiang University Zhongyuan Institute, Zhengzhou 450000, PR China.
| |
Collapse
|
9
|
Hernandez DE, Ciuparu A, Garcia da Silva P, Velasquez CM, Rebouillat B, Gross MD, Davis MB, Chae H, Muresan RC, Albeanu DF. Fast updating feedback from piriform cortex to the olfactory bulb relays multimodal identity and reward contingency signals during rule-reversal. Nat Commun 2025; 16:937. [PMID: 39843439 PMCID: PMC11754465 DOI: 10.1038/s41467-025-56023-5] [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: 11/06/2023] [Accepted: 01/02/2025] [Indexed: 01/24/2025] Open
Abstract
While animals readily adjust their behavior to adapt to relevant changes in the environment, the neural pathways enabling these changes remain largely unknown. Here, using multiphoton imaging, we investigate whether feedback from the piriform cortex to the olfactory bulb supports such behavioral flexibility. To this end, we engage head-fixed male mice in a multimodal rule-reversal task guided by olfactory and auditory cues. Both odor and, surprisingly, the sound cues trigger responses in the cortical bulbar feedback axons which precede the behavioral report. Responses to the same sensory cue are strongly modulated upon changes in stimulus-reward contingency (rule-reversals). The re-shaping of individual bouton responses occurs within seconds of the rule-reversal events and is correlated with changes in behavior. Optogenetic perturbation of cortical feedback within the bulb disrupts the behavioral performance. Our results indicate that the piriform-to-olfactory bulb feedback axons carry stimulus identity and reward contingency signals which are rapidly re-formatted according to changes in the behavioral context.
Collapse
Affiliation(s)
| | - Andrei Ciuparu
- Transylvanian Institute of Neuroscience, Cluj-Napoca, Romania
| | - Pedro Garcia da Silva
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
- Champalimaud Neuroscience Program, Lisbon, Portugal
| | - Cristina M Velasquez
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
- University of Oxford, Oxford, UK
| | - Benjamin Rebouillat
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
- École Normale Supérieure, Paris, France
| | | | - Martin B Davis
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Honggoo Chae
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Raul C Muresan
- Transylvanian Institute of Neuroscience, Cluj-Napoca, Romania.
- STAR-UBB Institute, Babeş-Bolyai University, Cluj-Napoca, Romania.
| | - Dinu F Albeanu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA.
- School for Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA.
| |
Collapse
|
10
|
Fink AJP, Muscinelli SP, Wang S, Hogan MI, English DF, Axel R, Litwin-Kumar A, Schoonover CE. Experience-dependent reorganization of inhibitory neuron synaptic connectivity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2025:2025.01.16.633450. [PMID: 39868262 PMCID: PMC11761011 DOI: 10.1101/2025.01.16.633450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/28/2025]
Abstract
Organisms continually tune their perceptual systems to the features they encounter in their environment1-3. We have studied how ongoing experience reorganizes the synaptic connectivity of neurons in the olfactory (piriform) cortex of the mouse. We developed an approach to measure synaptic connectivity in vivo, training a deep convolutional network to reliably identify monosynaptic connections from the spike-time cross-correlograms of 4.4 million single-unit pairs. This revealed that excitatory piriform neurons with similar odor tuning are more likely to be connected. We asked whether experience enhances this like-to-like connectivity but found that it was unaffected by odor exposure. Experience did, however, alter the logic of interneuron connectivity. Following repeated encounters with a set of odorants, inhibitory neurons that responded differentially to these stimuli exhibited a high degree of both incoming and outgoing synaptic connections within the cortical network. This reorganization depended only on the odor tuning of the inhibitory interneuron and not on the tuning of its pre- or postsynaptic partners. A computational model of this reorganized connectivity predicts that it increases the dimensionality of the entire network's responses to familiar stimuli, thereby enhancing their discriminability. We confirmed that this network-level property is present in physiological measurements, which showed increased dimensionality and separability of the evoked responses to familiar versus novel odorants. Thus, a simple, non-Hebbian reorganization of interneuron connectivity may selectively enhance an organism's discrimination of the features of its environment.
Collapse
Affiliation(s)
- Andrew J P Fink
- Department of Neurobiology, Northwestern University Evanston, IL
- Mortimer B. Zuckerman Mind Brain Behavior Institute Department of Neuroscience Columbia University New York, NY
| | - Samuel P Muscinelli
- Mortimer B. Zuckerman Mind Brain Behavior Institute Department of Neuroscience Columbia University New York, NY
| | - Shuqi Wang
- Mortimer B. Zuckerman Mind Brain Behavior Institute Department of Neuroscience Columbia University New York, NY
- École Polytechnique Fédérale de Lausanne Lausanne, Switzerland
| | - Marcus I Hogan
- Mortimer B. Zuckerman Mind Brain Behavior Institute Department of Neuroscience Columbia University New York, NY
- Neuroscience Graduate Program, University of California Berkeley Berkeley, CA
| | | | - Richard Axel
- Mortimer B. Zuckerman Mind Brain Behavior Institute Department of Neuroscience Columbia University New York, NY
- Howard Hughes Medical Institute
| | - Ashok Litwin-Kumar
- Mortimer B. Zuckerman Mind Brain Behavior Institute Department of Neuroscience Columbia University New York, NY
| | - Carl E Schoonover
- Mortimer B. Zuckerman Mind Brain Behavior Institute Department of Neuroscience Columbia University New York, NY
- Allen Institute for Neural Dynamics Seattle, WA
| |
Collapse
|
11
|
Yang P, Luo T, Yang S, Zhang A, Tang Y, Chen L, Wang J, Zhao Y, Zhong Z, Li X, Han Z, Zhang Y, Tang Y, Ma J, Jin L, Long K, Li M, Lu L. Identification of Olfactory Receptors Responding to Androstenone and the Key Structure Determinant in Domestic Pig. Curr Issues Mol Biol 2024; 47:13. [PMID: 39852128 PMCID: PMC11763519 DOI: 10.3390/cimb47010013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2024] [Revised: 12/13/2024] [Accepted: 12/21/2024] [Indexed: 01/26/2025] Open
Abstract
Olfactory receptors (ORs) are members of the transmembrane G protein-coupled receptor superfamily, playing a crucial role in odor recognition, which further mediates crucial biological processes in mammals. In sows, androstenone can trigger sexual behaviors through olfaction, but the underlying mechanism remains to be explored. To efficiently and accurately screen pig olfactory receptors responding to androstenone and the key structure determinant, we adapted the high-throughput RNA-seq strategy to screen the altered genes upon androstenone treatment in the olfactory epithelium of pigs, yielding 1397 downregulated genes. Of which, 15 OR genes and 49 OR-like genes were candidate androstenone-responsive genes, and 5 ORs (OR2D2, OR8D1, OR8D2, OR10Z1 and OR7D4) were proven as responsible for androstenone-mediated olfaction in vitro. Among the five ORs, pig OR7D4 has the highest level of androstenone response. To further find the structural determinant, we performed ligand-binding cavity analysis on pig OR7D4 with androstenone, predicted seven potential structural sites and further confirmed that F178 and T203 are the key sites for recognizing androstenone. Nevertheless, the natural non-synonymous mutation M133V (rs696400829) of pig OR7D4 was proven to significantly impair the respondence to androstenone. This is the first time the ORs responding to androstenone in pigs and the key structural determinant of pig OR7D4 were identified, which highlights the significance of investigating the role of OR7D4 in pig reproduction performance in the future.
Collapse
Affiliation(s)
- Peidong Yang
- State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 610000, China; (P.Y.); (T.L.); (S.Y.); (Y.T.); (Z.Z.); (X.L.); (Z.H.); (Y.Z.); (Y.T.); (J.M.); (L.J.); (K.L.)
| | - Tingting Luo
- State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 610000, China; (P.Y.); (T.L.); (S.Y.); (Y.T.); (Z.Z.); (X.L.); (Z.H.); (Y.Z.); (Y.T.); (J.M.); (L.J.); (K.L.)
| | - Shuqi Yang
- State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 610000, China; (P.Y.); (T.L.); (S.Y.); (Y.T.); (Z.Z.); (X.L.); (Z.H.); (Y.Z.); (Y.T.); (J.M.); (L.J.); (K.L.)
| | - Anjing Zhang
- Department of Pig Production, Chongqing Academy of Animal Science, Chongqing 402460, China; (A.Z.); (L.C.); (J.W.)
| | - Yuan Tang
- State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 610000, China; (P.Y.); (T.L.); (S.Y.); (Y.T.); (Z.Z.); (X.L.); (Z.H.); (Y.Z.); (Y.T.); (J.M.); (L.J.); (K.L.)
| | - Li Chen
- Department of Pig Production, Chongqing Academy of Animal Science, Chongqing 402460, China; (A.Z.); (L.C.); (J.W.)
| | - Jinyong Wang
- Department of Pig Production, Chongqing Academy of Animal Science, Chongqing 402460, China; (A.Z.); (L.C.); (J.W.)
| | - Yongju Zhao
- College of Animal Science and Technology, Southwest University, Chongqing 402460, China;
| | - Zhining Zhong
- State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 610000, China; (P.Y.); (T.L.); (S.Y.); (Y.T.); (Z.Z.); (X.L.); (Z.H.); (Y.Z.); (Y.T.); (J.M.); (L.J.); (K.L.)
| | - Xuemin Li
- State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 610000, China; (P.Y.); (T.L.); (S.Y.); (Y.T.); (Z.Z.); (X.L.); (Z.H.); (Y.Z.); (Y.T.); (J.M.); (L.J.); (K.L.)
| | - Ziyin Han
- State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 610000, China; (P.Y.); (T.L.); (S.Y.); (Y.T.); (Z.Z.); (X.L.); (Z.H.); (Y.Z.); (Y.T.); (J.M.); (L.J.); (K.L.)
| | - Yupei Zhang
- State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 610000, China; (P.Y.); (T.L.); (S.Y.); (Y.T.); (Z.Z.); (X.L.); (Z.H.); (Y.Z.); (Y.T.); (J.M.); (L.J.); (K.L.)
| | - Yue Tang
- State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 610000, China; (P.Y.); (T.L.); (S.Y.); (Y.T.); (Z.Z.); (X.L.); (Z.H.); (Y.Z.); (Y.T.); (J.M.); (L.J.); (K.L.)
| | - Jideng Ma
- State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 610000, China; (P.Y.); (T.L.); (S.Y.); (Y.T.); (Z.Z.); (X.L.); (Z.H.); (Y.Z.); (Y.T.); (J.M.); (L.J.); (K.L.)
| | - Long Jin
- State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 610000, China; (P.Y.); (T.L.); (S.Y.); (Y.T.); (Z.Z.); (X.L.); (Z.H.); (Y.Z.); (Y.T.); (J.M.); (L.J.); (K.L.)
| | - Keren Long
- State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 610000, China; (P.Y.); (T.L.); (S.Y.); (Y.T.); (Z.Z.); (X.L.); (Z.H.); (Y.Z.); (Y.T.); (J.M.); (L.J.); (K.L.)
| | - Mingzhou Li
- State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 610000, China; (P.Y.); (T.L.); (S.Y.); (Y.T.); (Z.Z.); (X.L.); (Z.H.); (Y.Z.); (Y.T.); (J.M.); (L.J.); (K.L.)
| | - Lu Lu
- State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 610000, China; (P.Y.); (T.L.); (S.Y.); (Y.T.); (Z.Z.); (X.L.); (Z.H.); (Y.Z.); (Y.T.); (J.M.); (L.J.); (K.L.)
- Department of Pig Production, Chongqing Academy of Animal Science, Chongqing 402460, China; (A.Z.); (L.C.); (J.W.)
- College of Animal Science and Technology, Southwest University, Chongqing 402460, China;
| |
Collapse
|
12
|
Gonzalez J, Torterolo P, Bolding KA, Tort AB. Communication subspace dynamics of the canonical olfactory pathway. iScience 2024; 27:111275. [PMID: 39628563 PMCID: PMC11613203 DOI: 10.1016/j.isci.2024.111275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2024] [Revised: 08/08/2024] [Accepted: 10/25/2024] [Indexed: 12/06/2024] Open
Abstract
Understanding how different brain areas communicate is crucial for elucidating the mechanisms underlying cognition. A possible way for neural populations to interact is through a communication subspace, a specific region in the state-space enabling the transmission of behaviorally relevant spiking patterns. In the olfactory system, it remains unclear if different populations employ such a mechanism. Our study reveals that neuronal ensembles in the main olfactory pathway (olfactory bulb to olfactory cortex) interact through a communication subspace, which is driven by nasal respiration and allows feedforward and feedback transmission to occur segregated along the sniffing cycle. Moreover, our results demonstrate that subspace communication depends causally on the activity of both areas, is hindered during anesthesia, and transmits a low-dimensional representation of odor.
Collapse
Affiliation(s)
- Joaquín Gonzalez
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo 11200, Uruguay
- Brain Institute, Federal University of Rio Grande do Norte, Natal, RN 59078, Brazil
| | - Pablo Torterolo
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo 11200, Uruguay
| | | | - Adriano B.L. Tort
- Brain Institute, Federal University of Rio Grande do Norte, Natal, RN 59078, Brazil
| |
Collapse
|
13
|
Wang D, Zhang Y, Li S, Liu P, Li X, Liu Z, Li A, Wang D. Orbitofrontal control of the olfactory cortex regulates olfactory discrimination learning. J Physiol 2024; 602:7003-7026. [PMID: 39549300 DOI: 10.1113/jp286606] [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: 03/31/2024] [Accepted: 10/24/2024] [Indexed: 11/18/2024] Open
Abstract
Serving as an integral node for cognitive processing and value-based decision-making, the orbitofrontal cortex (OFC) plays a multifaceted role in associative learning and reward-driven behaviours through its widespread synaptic integration with both subcortical structures and sensory cortices. Despite the OFC's robust innervation of the olfactory cortex, the functional implications and underlying mechanisms of this top-down influence remain largely unexplored. In this study, we demonstrated that the OFC formed both direct excitatory and indirect inhibitory synaptic connections with pyramidal neurons in the anterior piriform cortex (aPC). OFC projection predominantly regulated spontaneous and odour-evoked excitatory activity in the aPC of awake mice. Importantly, suppression of this OFC-aPC projection disrupted olfactory discrimination learning, potentially due to a consequent decrease in the excitability of aPC principal output neurons following inhibition of this projection. Whole-cell recordings revealed that olfactory learning increased the intrinsic excitability of aPC neurons while concurrently decreasing OFC input to these neurons. These findings underscore the pivotal influence of orbitofrontal modulation over the olfactory cortex in the context of olfactory learning and provide insight into the associated neurophysiological mechanisms. KEY POINTS: The orbitofrontal cortex (OFC) densely innervates the anterior piriform cortex (aPC) through direct excitatory synaptic connections. The OFC regulates both spontaneous and odour-evoked excitatory activities in the aPC of awake mice. Inhibition of OFC projections disrupts olfactory discrimination learning, probably due to reduced excitability of aPC main output neurons. Following olfactory learning, the intrinsic excitability of aPC neurons increases while the OFC-aPC input decreases, highlighting the importance of adaptable OFC input for olfactory learning. These results provide new perspectives on how the OFC's top-down control modulates sensory integration and associative learning.
Collapse
Affiliation(s)
- Ding Wang
- Jiangsu Key Laboratory of Brain Disease Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Ying Zhang
- Jiangsu Key Laboratory of Brain Disease Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Shan Li
- Jiangsu Key Laboratory of Brain Disease Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Penglai Liu
- Jiangsu Key Laboratory of Brain Disease Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Xiang Li
- Jiangsu Key Laboratory of Brain Disease Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Zhiqiu Liu
- Jiangsu Key Laboratory of Brain Disease Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Anan Li
- Jiangsu Key Laboratory of Brain Disease Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Dejuan Wang
- Jiangsu Key Laboratory of Brain Disease Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| |
Collapse
|
14
|
Pedroncini O, Federman N, Marin-Burgin A. Lateral entorhinal cortex afferents reconfigure the activity in piriform cortex circuits. Proc Natl Acad Sci U S A 2024; 121:e2414038121. [PMID: 39570314 PMCID: PMC11621770 DOI: 10.1073/pnas.2414038121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2024] [Accepted: 10/14/2024] [Indexed: 11/22/2024] Open
Abstract
Odors are key signals for guiding spatial behaviors such as foraging and navigation in rodents. Recent findings reveal that odor representations in the piriform cortex (PCx) also encode spatial context information. However, the brain origins of this information and its integration into PCx microcircuitry remain unclear. This study investigates the lateral entorhinal cortex (LEC) as a potential source of spatial contextual information affecting the PCx microcircuit and its olfactory responses. Using mice brain slices, we performed patch-clamp recordings on superficial (SP) and deep (DP) pyramidal neurons, as well as parvalbumin (PV) and somatostatin (SOM) inhibitory interneurons. Concurrently, we optogenetically stimulated excitatory LEC projections to observe their impact on PCx activity. Results show that LEC inputs are heterogeneously distributed in the PCx microcircuit, evoking larger excitatory currents in SP and PV neurons due to higher monosynaptic connectivity. LEC inputs also differentially affect inhibitory circuits, activating PV while suppressing SOM interneurons. Studying the interaction between LEC inputs and sensory signals from the lateral olfactory tract (LOT) revealed that simultaneous LEC and LOT activation increases spiking in SP and DP neurons, with DP neurons showing a sharpened response due to LEC-induced inhibition that suppresses delayed LOT-evoked spikes. This suggests a regulatory mechanism where LEC inputs inhibit recurrent activity by activating PV interneurons. Our findings demonstrate that LEC afferents reconfigure PCx activity, aiding the understanding of how odor objects form within the PCx by integrating olfactory and nonolfactory information.
Collapse
Affiliation(s)
- Olivia Pedroncini
- Instituto de Investigación en Biomedicina de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas-Partner Institute of the Max Planck Society, Buenos AiresC1425FQD, Argentina
| | - Noel Federman
- Instituto de Investigación en Biomedicina de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas-Partner Institute of the Max Planck Society, Buenos AiresC1425FQD, Argentina
| | - Antonia Marin-Burgin
- Instituto de Investigación en Biomedicina de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas-Partner Institute of the Max Planck Society, Buenos AiresC1425FQD, Argentina
| |
Collapse
|
15
|
Hu B, Temiz NZ, Chou CN, Rupprecht P, Meissner-Bernard C, Titze B, Chung S, Friedrich RW. Representational learning by optimization of neural manifolds in an olfactory memory network. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.11.17.623906. [PMID: 39605658 PMCID: PMC11601331 DOI: 10.1101/2024.11.17.623906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2024]
Abstract
Higher brain functions depend on experience-dependent representations of relevant information that may be organized by attractor dynamics or by geometrical modifications of continuous "neural manifolds". To explore these scenarios we analyzed odor-evoked activity in telencephalic area pDp of juvenile and adult zebrafish, the homolog of piriform cortex. No obvious signatures of attractor dynamics were detected. Rather, olfactory discrimination training selectively enhanced the separation of neural manifolds representing task-relevant odors from other representations, consistent with predictions of autoassociative network models endowed with precise synaptic balance. Analytical approaches using the framework of manifold capacity revealed multiple geometrical modifications of representational manifolds that supported the classification of task-relevant sensory information. Manifold capacity predicted odor discrimination across individuals, indicating a close link between manifold geometry and behavior. Hence, pDp and possibly related recurrent networks store information in the geometry of representational manifolds, resulting in joint sensory and semantic maps that may support distributed learning processes.
Collapse
Affiliation(s)
- Bo Hu
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland
- University of Basel, 4003 Basel, Switzerland
| | - Nesibe Z. Temiz
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland
- University of Basel, 4003 Basel, Switzerland
| | - Chi-Ning Chou
- Center for Computational Neuroscience, Flatiron Institute, New York, NY, USA
| | - Peter Rupprecht
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland
- Neuroscience Center Zurich, 8057 Zurich, Switzerland
- Brain Research Institute, University of Zurich, 8057 Zurich, Switzerland
| | - Claire Meissner-Bernard
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland
| | - Benjamin Titze
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland
| | - SueYeon Chung
- Center for Computational Neuroscience, Flatiron Institute, New York, NY, USA
- Center for Neural Science, New York University, New York, NY, USA
| | - Rainer W. Friedrich
- Friedrich Miescher Institute for Biomedical Research, Fabrikstrasse 24, 4056 Basel, Switzerland
- University of Basel, 4003 Basel, Switzerland
| |
Collapse
|
16
|
Hamel EA, Castro JB, Gould TJ, Pellegrino R, Liang Z, Coleman LA, Patel F, Wallace DS, Bhatnagar T, Mainland JD, Gerkin RC. Pyrfume: A window to the world's olfactory data. Sci Data 2024; 11:1220. [PMID: 39532906 PMCID: PMC11557823 DOI: 10.1038/s41597-024-04051-z] [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: 04/30/2024] [Accepted: 10/28/2024] [Indexed: 11/16/2024] Open
Abstract
Advances in theoretical understanding are frequently unlocked by access to large, diverse experimental datasets. Our understanding of olfactory neuroscience and psychophysics remain years behind the other senses, in part because rich datasets linking olfactory stimuli with their corresponding percepts, behaviors, and neural pathways remain scarce. Here we present a concerted effort to unlock and unify dozens of stimulus-linked olfactory datasets across species and modalities under a unified framework called Pyrfume. We present examples of how researchers might use Pyrfume to conduct novel analyses uncovering new principles, introduce trainees to the field, or construct benchmarks for machine olfaction.
Collapse
Affiliation(s)
| | - Jason B Castro
- Department of Neuroscience, Bates College, Lewiston, ME, USA
| | | | | | - Zhiwei Liang
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Liyah A Coleman
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Famesh Patel
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Derek S Wallace
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | | | - Joel D Mainland
- Monell Chemical Senses Center, Philadelphia, PA, USA.
- University of Pennsylvania, Philadelphia, PA, USA.
| | - Richard C Gerkin
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
- Osmo, New York, NY, USA
| |
Collapse
|
17
|
Grimaud J, Dorrell W, Jayakumar S, Pehlevan C, Murthy V. Bilateral Alignment of Receptive Fields in the Olfactory Cortex. eNeuro 2024; 11:ENEURO.0155-24.2024. [PMID: 39433407 PMCID: PMC11540595 DOI: 10.1523/eneuro.0155-24.2024] [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: 04/04/2024] [Revised: 09/06/2024] [Accepted: 10/11/2024] [Indexed: 10/23/2024] Open
Abstract
Each olfactory cortical hemisphere receives ipsilateral odor information directly from the olfactory bulb and contralateral information indirectly from the other cortical hemisphere. Since neural projections to the olfactory cortex (OC) are disordered and nontopographic, spatial information cannot be used to align projections from the two sides like in the visual cortex. Therefore, how bilateral information is integrated in individual cortical neurons is unknown. We have found, in mice, that the odor responses of individual neurons to selective stimulation of each of the two nostrils are significantly correlated, such that odor identity decoding optimized with information arriving from one nostril transfers very well to the other side. Nevertheless, these aligned responses are asymmetric enough to allow decoding of stimulus laterality. Computational analysis shows that such matched odor tuning is incompatible with purely random connections but is explained readily by Hebbian plasticity structuring bilateral connectivity. Our data reveal that despite the distributed and fragmented sensory representation in the OC, odor information across the two hemispheres is highly coordinated.
Collapse
Affiliation(s)
- Julien Grimaud
- Molecules, Cells, and Organisms Graduate Program, Harvard University, Cambridge, Massachusetts 02138
- Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, Massachusetts 02138
- Center for Brain Science, Harvard University, Cambridge, Massachusetts 02138
- Cell Engineering Laboratory (CellTechs), SupBiotech, 94800 Villejuif, France
| | - William Dorrell
- Center for Brain Science, Harvard University, Cambridge, Massachusetts 02138
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138
| | - Siddharth Jayakumar
- Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, Massachusetts 02138
- Center for Brain Science, Harvard University, Cambridge, Massachusetts 02138
| | - Cengiz Pehlevan
- Center for Brain Science, Harvard University, Cambridge, Massachusetts 02138
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138
- Kempner Institute for Natural and Artificial Intelligence, Harvard University, Cambridge, Massachusetts 02138
| | - Venkatesh Murthy
- Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, Massachusetts 02138
- Center for Brain Science, Harvard University, Cambridge, Massachusetts 02138
- Kempner Institute for Natural and Artificial Intelligence, Harvard University, Cambridge, Massachusetts 02138
| |
Collapse
|
18
|
Browne TJ, Smith KM, Gradwell MA, Dayas CV, Callister RJ, Hughes DI, Graham BA. Lateral lamina V projection neuron axon collaterals connect sensory processing across the dorsal horn of the mouse spinal cord. Sci Rep 2024; 14:26354. [PMID: 39487174 PMCID: PMC11530558 DOI: 10.1038/s41598-024-73620-4] [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: 02/01/2024] [Accepted: 09/19/2024] [Indexed: 11/04/2024] Open
Abstract
Spinal projection neurons (PNs) are defined by long axons that travel from their origin in the spinal cord to the brain where they relay sensory information from the body. The existence and function of a substantial axon collateral network, also arising from PNs and remaining within the spinal cord, is less well appreciated. Here we use a retrograde viral transduction strategy to characterise a novel subpopulation of deep dorsal horn spinoparabrachial neurons. Brainbow assisted analysis confirmed that virally labelled PN cell bodies formed a discrete cell column in the lateral part of Lamina V (LVlat) and the adjoining white matter. These PNs exhibited large dendritic territories biased to regions lateral and ventral to the cell body column and extending considerable rostrocaudal distances. Optogenetic activation of LVLat PNs confirmed this population mediates widespread signalling within spinal cord circuits, including activation in the superficial dorsal horn. This signalling was also demonstrated with patch clamp recordings during LVLat PN photostimulation, with a range of direct and indirect connections identified and evidence of a postsynaptic population of inhibitory interneurons. Together, these findings confirm a substantial role for PNs in local spinal sensory processing, as well as relay of sensory signals to the brain.
Collapse
Affiliation(s)
- Tyler J Browne
- School of Biomedical Sciences and Pharmacy, Faculty of Health, University of Newcastle, Callaghan, NSW, 2308, Australia.
- Hunter Medical Research Institute (HMRI), New Lambton Heights, NSW, Australia.
| | - Kelly M Smith
- Department of Neurobiology and the Pittsburgh Center for Pain Research, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Mark A Gradwell
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
- W.M. Keck Center for Collaborative Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Christopher V Dayas
- School of Biomedical Sciences and Pharmacy, Faculty of Health, University of Newcastle, Callaghan, NSW, 2308, Australia
- Hunter Medical Research Institute (HMRI), New Lambton Heights, NSW, Australia
| | - Robert J Callister
- School of Biomedical Sciences and Pharmacy, Faculty of Health, University of Newcastle, Callaghan, NSW, 2308, Australia
- Hunter Medical Research Institute (HMRI), New Lambton Heights, NSW, Australia
| | - David I Hughes
- Institute of Neuroscience Psychology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Brett A Graham
- School of Biomedical Sciences and Pharmacy, Faculty of Health, University of Newcastle, Callaghan, NSW, 2308, Australia
- Hunter Medical Research Institute (HMRI), New Lambton Heights, NSW, Australia
| |
Collapse
|
19
|
Wolf D, Oettl LL, Winkelmeier L, Linster C, Kelsch W. Anterior Olfactory Cortices Differentially Transform Bottom-Up Odor Signals to Produce Inverse Top-Down Outputs. J Neurosci 2024; 44:e0231242024. [PMID: 39266300 PMCID: PMC11529817 DOI: 10.1523/jneurosci.0231-24.2024] [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: 01/29/2024] [Revised: 07/13/2024] [Accepted: 08/20/2024] [Indexed: 09/14/2024] Open
Abstract
Odor information arrives first in the main olfactory bulb and is then broadcasted to the olfactory cortices and striatum. Downstream regions have unique cellular and connectivity architectures that may generate different coding patterns to the same odors. To reveal region-specific response features, tuning and decoding of single-unit populations, we recorded responses to the same odors under the same conditions across regions, namely, the main olfactory bulb (MOB), the anterior olfactory nucleus (AON), the anterior piriform cortex (aPC), and the olfactory tubercle of the ventral striatum (OT), of awake male mice. We focused on chemically closely related aldehydes that still create distinct percepts. The MOB had the highest decoding accuracy for aldehydes and was the only region encoding chemical similarity. The MOB had the highest fraction of inhibited responses and narrowly tuned odor-excited responses in terms of timing and odor selectivity. Downstream, the interconnected AON and aPC differed in their response patterns to the same stimuli. While odor-excited responses dominated the AON, the aPC had a comparably high fraction of odor-inhibited responses. Both cortices share a main output target that is the MOB. This prompted us to test if the two regions convey also different net outputs. Aldehydes activated AON terminals in the MOB as a bulk signal but inhibited those from the aPC. The differential cortical projection responses generalized to complex odors. In summary, olfactory regions reveal specialized features in their encoding with AON and aPC differing in their local computations, thereby generating inverse net centrifugal and intercortical outputs.
Collapse
Affiliation(s)
- David Wolf
- Department of Psychiatry and Psychotherapy, University Medical Center, Johannes Gutenberg University, Mainz 55131, Germany
- Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim 68159, Germany
| | - Lars-Lennart Oettl
- Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim 68159, Germany
| | - Laurens Winkelmeier
- Department of Psychiatry and Psychotherapy, University Medical Center, Johannes Gutenberg University, Mainz 55131, Germany
| | - Christiane Linster
- Computational Physiology Laboratory, Department of Neurobiology and Behavior, Cornell University, Ithaca, New York 14850
| | - Wolfgang Kelsch
- Department of Psychiatry and Psychotherapy, University Medical Center, Johannes Gutenberg University, Mainz 55131, Germany
- Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim 68159, Germany
| |
Collapse
|
20
|
Lazar AA, Liu T, Yeh CH, Zhou Y. Modeling and characterization of pure and odorant mixture processing in the Drosophila mushroom body calyx. Front Physiol 2024; 15:1410946. [PMID: 39479309 PMCID: PMC11521939 DOI: 10.3389/fphys.2024.1410946] [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: 04/02/2024] [Accepted: 09/05/2024] [Indexed: 11/02/2024] Open
Abstract
Associative memory in the Mushroom Body of the fruit fly brain depends on the encoding and processing of odorants in the first three stages of the Early Olfactory System: the Antenna, the Antennal Lobe and the Mushroom Body Calyx. The Kenyon Cells (KCs) of the Calyx provide the Mushroom Body compartments the identity of pure and odorant mixtures encoded as a train of spikes. Characterizing the code underlying the KC spike trains is a major challenge in neuroscience. To address this challenge we start by explicitly modeling the space of odorants using constructs of both semantic and syntactic information. Odorant semantics concerns the identity of odorants while odorant syntactics pertains to their concentration amplitude. These odorant attributes are multiplicatively coupled in the process of olfactory transduction. A key question that early olfactory systems must address is how to disentangle the odorant semantic information from the odorant syntactic information. To address the untanglement we devised an Odorant Encoding Machine (OEM) modeling the first three stages of early olfactory processing in the fruit fly brain. Each processing stage is modeled by Divisive Normalization Processors (DNPs). DNPs are spatio-temporal models of canonical computation of brain circuits. The end-to-end OEM is constructed as cascaded DNPs. By extensively modeling and characterizing the processing of pure and odorant mixtures in the Calyx, we seek to answer the question of its functional significance. We demonstrate that the DNP circuits in the OEM combinedly reduce the variability of the Calyx response to odorant concentration, thereby separating odorant semantic information from syntactic information. We then advance a code, called first spike sequence code, that the KCs make available at the output of the Calyx. We show that the semantics of odorants can be represented by this code in the spike domain and is ready for easy memory access in the Mushroom Body compartments.
Collapse
Affiliation(s)
- Aurel A. Lazar
- Bionet Group, Department of Electrical Engineering, Columbia University, New York, NY, United States
| | - Tingkai Liu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, United States
| | - Chung-Heng Yeh
- Bionet Group, Department of Electrical Engineering, Columbia University, New York, NY, United States
| | - Yiyin Zhou
- Department of Computer and Information Science, Fordham University, New York, NY, United States
| |
Collapse
|
21
|
Wang P, Li S, Li A. Odor representation and coding by the mitral/tufted cells in the olfactory bulb. J Zhejiang Univ Sci B 2024; 25:824-840. [PMID: 39420520 PMCID: PMC11494158 DOI: 10.1631/jzus.b2400051] [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: 01/30/2024] [Accepted: 07/14/2024] [Indexed: 10/19/2024]
Abstract
The olfactory bulb (OB) is the first relay station in the olfactory system and functions as a crucial hub. It can represent odor information precisely and accurately in an ever-changing environment. As the only output neurons in the OB, mitral/tufted cells encode information such as odor identity and concentration. Recently, the neural strategies and mechanisms underlying odor representation and encoding in the OB have been investigated extensively. Here we review the main progress on this topic. We first review the neurons and circuits involved in odor representation, including the different cell types in the OB and the neural circuits within and beyond the OB. We will then discuss how two different coding strategies-spatial coding and temporal coding-work in the rodent OB. Finally, we discuss potential future directions for this research topic. Overall, this review provides a comprehensive description of our current understanding of how odor information is represented and encoded by mitral/tufted cells in the OB.
Collapse
Affiliation(s)
- Panke Wang
- School of Biomedical Engineering, Guangdong Medical University, Dongguan 523808, China
| | - Shan Li
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221002, China
| | - An'an Li
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221002, China.
| |
Collapse
|
22
|
Belonio KC, Haile ES, Fyke Z, Vivona L, Konanur V, Zak JD. Amplification of olfactory transduction currents implements sparse stimulus encoding. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.10.11.617893. [PMID: 39416025 PMCID: PMC11482904 DOI: 10.1101/2024.10.11.617893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 10/19/2024]
Abstract
Sensory systems must perform the dual and opposing tasks of being sensitive to weak stimuli while also maintaining information content in dense and variable sensory landscapes. This occurs in the olfactory system, where OSNs are highly sensitive to low concentrations of odors and maintain discriminability in complex odor environments. How olfactory sensory neurons (OSNs) maintain both sensitivity and sparsity is not well understood. Here, we investigated whether the calcium-activated chloride channel, TMEM16B, may support these dual roles in OSNs. We used multiphoton microscopy to image the stimulus-response density of OSNs in the olfactory epithelium. In TMEM16B knockout mice, we found that sensory representations were denser, and the magnitude of OSN responses was increased. Behaviorally, these changes in sensory representations were associated with an increased aversion to the odorant trimethylamine, which switches perceptual valence as its concentration increases, and a decreased efficiency of olfactory-guided navigation. Together, our results indicate that the calcium-activated chloride channel TMEM16B sparsens sensory representations in the peripheral olfactory system and contributes to efficient integrative olfactory-guided behaviors.
Collapse
Affiliation(s)
- Kai Clane Belonio
- Department of Biological Sciences, University of Illinois Chicago, 60607
| | - Eyerusalem S. Haile
- Graduate Program in Biological Sciences, University of Illinois Chicago, 60607
| | - Zach Fyke
- Graduate Program in Neuroscience, University of Illinois Chicago, 60607
| | - Lindsay Vivona
- Graduate Program in Biological Sciences, University of Illinois Chicago, 60607
| | - Vaibhav Konanur
- Department of Biological Sciences, University of Illinois Chicago, 60607
| | - Joseph D. Zak
- Department of Biological Sciences, University of Illinois Chicago, 60607
- Department of Psychology, University of Illinois Chicago, 60607
| |
Collapse
|
23
|
Rokni D, Ben-Shaul Y. Object-oriented olfaction: challenges for chemosensation and for chemosensory research. Trends Neurosci 2024; 47:834-848. [PMID: 39245626 DOI: 10.1016/j.tins.2024.08.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 08/02/2024] [Accepted: 08/16/2024] [Indexed: 09/10/2024]
Abstract
Many animal species use olfaction to extract information about objects in their environment. Yet, the specific molecular signature that any given object emits varies due to various factors. Here, we detail why such variability makes chemosensory-mediated object recognition such a hard problem, and we propose that a major function of the elaborate chemosensory network is to overcome it. We describe previous work addressing different elements of the problem and outline future research directions that we consider essential for a full understanding of object-oriented olfaction. In particular, we call for extensive representation of olfactory object variability in chemical, behavioral, and electrophysiological analyses. While written with an emphasis on macrosmatic mammalian species, our arguments apply to all organisms that employ chemosensation to navigate complex environments.
Collapse
Affiliation(s)
- Dan Rokni
- Department of Medical Neurobiology, The Hebrew University Faculty of Medicine, Institute for Medical Research, Israel-Canada (IMRIC), Jerusalem, Israel.
| | - Yoram Ben-Shaul
- Department of Medical Neurobiology, The Hebrew University Faculty of Medicine, Institute for Medical Research, Israel-Canada (IMRIC), Jerusalem, Israel.
| |
Collapse
|
24
|
Pirhayati D, Smith CL, Kroeger R, Navlakha S, Pfaffinger P, Reimer J, Arenkiel BR, Patel A, Moss EH. Dense and Persistent Odor Representations in the Olfactory Bulb of Awake Mice. J Neurosci 2024; 44:e0116242024. [PMID: 39187379 PMCID: PMC11426377 DOI: 10.1523/jneurosci.0116-24.2024] [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: 02/08/2024] [Revised: 08/12/2024] [Accepted: 08/14/2024] [Indexed: 08/28/2024] Open
Abstract
Recording and analysis of neural activity are often biased toward detecting sparse subsets of highly active neurons, masking important signals carried in low-magnitude and variable responses. To investigate the contribution of seemingly noisy activity to odor encoding, we used mesoscale calcium imaging from mice of both sexes to record odor responses from the dorsal surface of bilateral olfactory bulbs (OBs). The outer layer of the mouse OB is comprised of dendrites organized into discrete "glomeruli," which are defined by odor receptor-specific sensory neuron input. We extracted activity from a large population of glomeruli and used logistic regression to classify odors from individual trials with high accuracy. We then used add-in and dropout analyses to determine subsets of glomeruli necessary and sufficient for odor classification. Classifiers successfully predicted odor identity even after excluding sparse, highly active glomeruli, indicating that odor information is redundantly represented across a large population of glomeruli. Additionally, we found that random forest (RF) feature selection informed by Gini inequality (RF Gini impurity, RFGI) reliably ranked glomeruli by their contribution to overall odor classification. RFGI provided a measure of "feature importance" for each glomerulus that correlated with intuitive features like response magnitude. Finally, in agreement with previous work, we found that odor information persists in glomerular activity after the odor offset. Together, our findings support a model of OB odor coding where sparse activity is sufficient for odor identification, but information is widely, redundantly available across a large population of glomeruli, with each glomerulus representing information about more than one odor.
Collapse
Affiliation(s)
- Delaram Pirhayati
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 97030
| | - Cameron L Smith
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 97030
| | - Ryan Kroeger
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 97030
| | - Saket Navlakha
- Cold Spring Harbor Laboratory, Cold Spring Harbor, Laurel Hollow, New York 11724
| | - Paul Pfaffinger
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 97030
| | - Jacob Reimer
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 97030
| | - Benjamin R Arenkiel
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 97030
| | - Ankit Patel
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 97030
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 97030
| | - Elizabeth H Moss
- Department of Anesthesiology and Perioperative Medicine, Oregon Health & Science University, Portland, Oregon 97239
| |
Collapse
|
25
|
Wang DC, Santos-Valencia F, Song JH, Franks KM, Luo L. Embryonically active piriform cortex neurons promote intracortical recurrent connectivity during development. Neuron 2024; 112:2938-2954.e6. [PMID: 38964330 PMCID: PMC11377168 DOI: 10.1016/j.neuron.2024.06.007] [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: 07/24/2023] [Revised: 04/28/2024] [Accepted: 06/11/2024] [Indexed: 07/06/2024]
Abstract
Neuronal activity plays a critical role in the maturation of circuits that propagate sensory information into the brain. How widely does early activity regulate circuit maturation across the developing brain? Here, we used targeted recombination in active populations (TRAP) to perform a brain-wide survey for prenatally active neurons in mice and identified the piriform cortex as an abundantly TRAPed region. Whole-cell recordings in neonatal slices revealed preferential interconnectivity within embryonically TRAPed piriform neurons and their enhanced synaptic connectivity with other piriform neurons. In vivo Neuropixels recordings in neonates demonstrated that embryonically TRAPed piriform neurons exhibit broad functional connectivity within piriform and lead spontaneous synchronized population activity during a transient neonatal period, when recurrent connectivity is strengthening. Selectively activating or silencing these neurons in neonates enhanced or suppressed recurrent synaptic strength, respectively. Thus, embryonically TRAPed piriform neurons represent an interconnected hub-like population whose activity promotes recurrent connectivity in early development.
Collapse
Affiliation(s)
- David C Wang
- Howard Hughes Medical Institute and Department of Biology, Stanford University, Stanford, CA 94305, USA; Stanford MSTP, Stanford, CA 94305, USA
| | | | - Jun H Song
- Howard Hughes Medical Institute and Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Kevin M Franks
- Department of Neurobiology, Duke University School of Medicine, Durham, NC 27710, USA.
| | - Liqun Luo
- Howard Hughes Medical Institute and Department of Biology, Stanford University, Stanford, CA 94305, USA.
| |
Collapse
|
26
|
Giaffar H, Shuvaev S, Rinberg D, Koulakov AA. The primacy model and the structure of olfactory space. PLoS Comput Biol 2024; 20:e1012379. [PMID: 39255274 PMCID: PMC11423968 DOI: 10.1371/journal.pcbi.1012379] [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: 12/05/2023] [Revised: 09/25/2024] [Accepted: 07/30/2024] [Indexed: 09/12/2024] Open
Abstract
Understanding sensory processing involves relating the stimulus space, its neural representation, and perceptual quality. In olfaction, the difficulty in establishing these links lies partly in the complexity of the underlying odor input space and perceptual responses. Based on the recently proposed primacy model for concentration invariant odor identity representation and a few assumptions, we have developed a theoretical framework for mapping the odor input space to the response properties of olfactory receptors. We analyze a geometrical structure containing odor representations in a multidimensional space of receptor affinities and describe its low-dimensional implementation, the primacy hull. We propose the implications of the primacy hull for the structure of feedforward connectivity in early olfactory networks. We test the predictions of our theory by comparing the existing receptor-ligand affinity and connectivity data obtained in the fruit fly olfactory system. We find that the Kenyon cells of the insect mushroom body integrate inputs from the high-affinity (primacy) sets of olfactory receptors in agreement with the primacy theory.
Collapse
Affiliation(s)
- Hamza Giaffar
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Sergey Shuvaev
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Dmitry Rinberg
- Neuroscience Institute, New York University Langone Health, New York, New York, United States of America
- Center for Neural Science, New York University, New York, New York, United States of America
| | - Alexei A. Koulakov
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| |
Collapse
|
27
|
Federman N, Romano SA, Amigo-Duran M, Salomon L, Marin-Burgin A. Acquisition of non-olfactory encoding improves odour discrimination in olfactory cortex. Nat Commun 2024; 15:5572. [PMID: 38956072 PMCID: PMC11220071 DOI: 10.1038/s41467-024-49897-4] [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: 09/20/2023] [Accepted: 06/20/2024] [Indexed: 07/04/2024] Open
Abstract
Olfaction is influenced by contextual factors, past experiences, and the animal's internal state. Whether this information is integrated at the initial stages of cortical odour processing is not known, nor how these signals may influence odour encoding. Here we revealed multiple and diverse non-olfactory responses in the primary olfactory (piriform) cortex (PCx), which dynamically enhance PCx odour discrimination according to behavioural demands. We performed recordings of PCx neurons from mice trained in a virtual reality task to associate odours with visual contexts to obtain a reward. We found that learning shifts PCx activity from encoding solely odours to a regime in which positional, contextual, and associative responses emerge on odour-responsive neurons that become mixed-selective. The modulation of PCx activity by these non-olfactory signals was dynamic, improving odour decoding during task engagement and in rewarded contexts. This improvement relied on the acquired mixed-selectivity, demonstrating how integrating extra-sensory inputs in sensory cortices can enhance sensory processing while encoding the behavioural relevance of stimuli.
Collapse
Grants
- 108878 Canadian International Development Agency (Agence Canadienne de Développement International)
- PICT2018-0880 Ministry of Science, Technology and Productive Innovation, Argentina | National Agency for Science and Technology, Argentina | Fondo para la Investigación Científica y Tecnológica (Fund for Scientific and Technological Research)
- PICT2020-0360 Ministry of Science, Technology and Productive Innovation, Argentina | National Agency for Science and Technology, Argentina | Fondo para la Investigación Científica y Tecnológica (Fund for Scientific and Technological Research)
- PICT2020-1536 Ministry of Science, Technology and Productive Innovation, Argentina | National Agency for Science and Technology, Argentina | Fondo para la Investigación Científica y Tecnológica (Fund for Scientific and Technological Research)
- PICT2016-2758 Ministry of Science, Technology and Productive Innovation, Argentina | National Agency for Science and Technology, Argentina | Fondo para la Investigación Científica y Tecnológica (Fund for Scientific and Technological Research)
- PICT2017-4023 Ministry of Science, Technology and Productive Innovation, Argentina | National Agency for Science and Technology, Argentina | Fondo para la Investigación Científica y Tecnológica (Fund for Scientific and Technological Research)
- PIP2787 Ministerio de Ciencia, Tecnología e Innovación Productiva (Ministry of Science, Technology and Productive Innovation, Argentina)
- SPIRIT 216044 Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (Swiss National Science Foundation)
- Fondo para la convergencia estructural del Mercosur–FOCEM grant cOF 03/11
Collapse
Affiliation(s)
- Noel Federman
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Godoy Cruz 2390, C1425FQD, Buenos Aires, Argentina.
| | - Sebastián A Romano
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Godoy Cruz 2390, C1425FQD, Buenos Aires, Argentina.
| | - Macarena Amigo-Duran
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Godoy Cruz 2390, C1425FQD, Buenos Aires, Argentina
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, PhD Program, Buenos Aires, Argentina
| | - Lucca Salomon
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Godoy Cruz 2390, C1425FQD, Buenos Aires, Argentina
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, PhD Program, Buenos Aires, Argentina
| | - Antonia Marin-Burgin
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Godoy Cruz 2390, C1425FQD, Buenos Aires, Argentina.
| |
Collapse
|
28
|
Fulton KA, Zimmerman D, Samuel A, Vogt K, Datta SR. Common principles for odour coding across vertebrates and invertebrates. Nat Rev Neurosci 2024; 25:453-472. [PMID: 38806946 DOI: 10.1038/s41583-024-00822-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/30/2024] [Indexed: 05/30/2024]
Abstract
The olfactory system is an ideal and tractable system for exploring how the brain transforms sensory inputs into behaviour. The basic tasks of any olfactory system include odour detection, discrimination and categorization. The challenge for the olfactory system is to transform the high-dimensional space of olfactory stimuli into the much smaller space of perceived objects and valence that endows odours with meaning. Our current understanding of how neural circuits address this challenge has come primarily from observations of the mechanisms of the brain for processing other sensory modalities, such as vision and hearing, in which optimized deep hierarchical circuits are used to extract sensory features that vary along continuous physical dimensions. The olfactory system, by contrast, contends with an ill-defined, high-dimensional stimulus space and discrete stimuli using a circuit architecture that is shallow and parallelized. Here, we present recent observations in vertebrate and invertebrate systems that relate the statistical structure and state-dependent modulation of olfactory codes to mechanisms of perception and odour-guided behaviour.
Collapse
Affiliation(s)
- Kara A Fulton
- Department of Neuroscience, Harvard Medical School, Boston, MA, USA
| | - David Zimmerman
- Department of Physics, Harvard University, Cambridge, MA, USA
| | - Aravi Samuel
- Department of Physics, Harvard University, Cambridge, MA, USA
| | - Katrin Vogt
- Department of Physics, Harvard University, Cambridge, MA, USA.
- Department of Biology, University of Konstanz, Konstanz, Germany.
- Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany.
| | | |
Collapse
|
29
|
McKissick O, Klimpert N, Ritt JT, Fleischmann A. Odors in space. Front Neural Circuits 2024; 18:1414452. [PMID: 38978957 PMCID: PMC11228174 DOI: 10.3389/fncir.2024.1414452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Accepted: 05/29/2024] [Indexed: 07/10/2024] Open
Abstract
As an evolutionarily ancient sense, olfaction is key to learning where to find food, shelter, mates, and important landmarks in an animal's environment. Brain circuitry linking odor and navigation appears to be a well conserved multi-region system among mammals; the anterior olfactory nucleus, piriform cortex, entorhinal cortex, and hippocampus each represent different aspects of olfactory and spatial information. We review recent advances in our understanding of the neural circuits underlying odor-place associations, highlighting key choices of behavioral task design and neural circuit manipulations for investigating learning and memory.
Collapse
Affiliation(s)
- Olivia McKissick
- Department of Neuroscience and Carney Institute for Brain Science, Brown University, Providence, RI, United States
| | - Nell Klimpert
- Department of Neuroscience and Carney Institute for Brain Science, Brown University, Providence, RI, United States
| | - Jason T Ritt
- Carney Institute for Brain Science, Brown University, Providence, RI, United States
| | - Alexander Fleischmann
- Department of Neuroscience and Carney Institute for Brain Science, Brown University, Providence, RI, United States
| |
Collapse
|
30
|
Wang DC, Santos-Valencia F, Song JH, Franks KM, Luo L. Embryonically Active Piriform Cortex Neurons Promote Intracortical Recurrent Connectivity during Development. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.08.593265. [PMID: 38766173 PMCID: PMC11100831 DOI: 10.1101/2024.05.08.593265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Neuronal activity plays a critical role in the maturation of circuits that propagate sensory information into the brain. How widely does early activity regulate circuit maturation across the developing brain? Here, we used Targeted Recombination in Active Populations (TRAP) to perform a brain-wide survey for prenatally active neurons in mice and identified the piriform cortex as an abundantly TRAPed region. Whole-cell recordings in neonatal slices revealed preferential interconnectivity within embryonically TRAPed piriform neurons and their enhanced synaptic connectivity with other piriform neurons. In vivo Neuropixels recordings in neonates demonstrated that embryonically TRAPed piriform neurons exhibit broad functional connectivity within piriform and lead spontaneous synchronized population activity during a transient neonatal period, when recurrent connectivity is strengthening. Selectively activating or silencing of these neurons in neonates enhanced or suppressed recurrent synaptic strength, respectively. Thus, embryonically TRAPed piriform neurons represent an interconnected hub-like population whose activity promotes recurrent connectivity in early development.
Collapse
|
31
|
A Dehaqani A, Michelon F, Patella P, Petrucco L, Piasini E, Iurilli G. A mechanosensory feedback that uncouples external and self-generated sensory responses in the olfactory cortex. Cell Rep 2024; 43:114013. [PMID: 38551962 DOI: 10.1016/j.celrep.2024.114013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 12/20/2023] [Accepted: 03/13/2024] [Indexed: 04/28/2024] Open
Abstract
Sampling behaviors have sensory consequences that can hinder perceptual stability. In olfaction, sniffing affects early odor encoding, mimicking a sudden change in odor concentration. We examined how the inhalation speed affects the representation of odor concentration in the main olfactory cortex. Neurons combine the odor input with a global top-down signal preceding the sniff and a mechanosensory feedback generated by the air passage through the nose during inhalation. Still, the population representation of concentration is remarkably sniff invariant. This is because the mechanosensory and olfactory responses are uncorrelated within and across neurons. Thus, faster odor inhalation and an increase in concentration change the cortical activity pattern in distinct ways. This encoding strategy affords tolerance to potential concentration fluctuations caused by varying inhalation speeds. Since mechanosensory reafferences are widespread across sensory systems, the coding scheme described here may be a canonical strategy to mitigate the sensory ambiguities caused by movements.
Collapse
Affiliation(s)
- Alireza A Dehaqani
- Center for Neuroscience and Cognitive Systems, Istituto Italiano di Tecnologia, 38068 Rovereto, Italy; CIMeC, University of Trento, 38068 Rovereto, Italy
| | - Filippo Michelon
- Center for Neuroscience and Cognitive Systems, Istituto Italiano di Tecnologia, 38068 Rovereto, Italy; CIMeC, University of Trento, 38068 Rovereto, Italy
| | - Paola Patella
- Center for Neuroscience and Cognitive Systems, Istituto Italiano di Tecnologia, 38068 Rovereto, Italy
| | - Luigi Petrucco
- Center for Neuroscience and Cognitive Systems, Istituto Italiano di Tecnologia, 38068 Rovereto, Italy
| | - Eugenio Piasini
- International School for Advanced Studies (SISSA), Trieste, Italy
| | - Giuliano Iurilli
- Center for Neuroscience and Cognitive Systems, Istituto Italiano di Tecnologia, 38068 Rovereto, Italy.
| |
Collapse
|
32
|
Zak JD, Reddy G, Konanur V, Murthy VN. Distinct information conveyed to the olfactory bulb by feedforward input from the nose and feedback from the cortex. Nat Commun 2024; 15:3268. [PMID: 38627390 PMCID: PMC11021479 DOI: 10.1038/s41467-024-47366-6] [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: 10/19/2023] [Accepted: 03/29/2024] [Indexed: 04/19/2024] Open
Abstract
Sensory systems are organized hierarchically, but feedback projections frequently disrupt this order. In the olfactory bulb (OB), cortical feedback projections numerically match sensory inputs. To unravel information carried by these two streams, we imaged the activity of olfactory sensory neurons (OSNs) and cortical axons in the mouse OB using calcium indicators, multiphoton microscopy, and diverse olfactory stimuli. Here, we show that odorant mixtures of increasing complexity evoke progressively denser OSN activity, yet cortical feedback activity is of similar sparsity for all stimuli. Also, representations of complex mixtures are similar in OSNs but are decorrelated in cortical axons. While OSN responses to increasing odorant concentrations exhibit a sigmoidal relationship, cortical axonal responses are complex and nonmonotonic, which can be explained by a model with activity-dependent feedback inhibition in the cortex. Our study indicates that early-stage olfactory circuits have access to local feedforward signals and global, efficiently formatted information about odor scenes through cortical feedback.
Collapse
Affiliation(s)
- Joseph D Zak
- Department of Biological Sciences, University of Illinois Chicago, Chicago, IL, 60607, USA.
- Department of Psychology, University of Illinois Chicago, Chicago, IL, 60607, USA.
| | - Gautam Reddy
- Physics & Informatics Laboratories, NTT Research, Inc., Sunnyvale, CA, 94085, USA
- Department of Physics, Princeton University, Princeton, NJ, 08540, USA
- Center for Brain Science, Harvard University, Cambridge, MA, 02138, USA
| | - Vaibhav Konanur
- Department of Biological Sciences, University of Illinois Chicago, Chicago, IL, 60607, USA
| | - Venkatesh N Murthy
- Center for Brain Science, Harvard University, Cambridge, MA, 02138, USA
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, 02138, USA
- Kempner Institute for the Study of Natural and Artificial Intelligence, Harvard University, Allston, 02134, USA
| |
Collapse
|
33
|
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
|
34
|
Barreiro AK, Fontenele AJ, Ly C, Raju PC, Gautam SH, Shew WL. Sensory input to cortex encoded on low-dimensional periphery-correlated subspaces. PNAS NEXUS 2024; 3:pgae010. [PMID: 38250515 PMCID: PMC10798852 DOI: 10.1093/pnasnexus/pgae010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 12/29/2023] [Indexed: 01/23/2024]
Abstract
As information about the world is conveyed from the sensory periphery to central neural circuits, it mixes with complex ongoing cortical activity. How do neural populations keep track of sensory signals, separating them from noisy ongoing activity? Here, we show that sensory signals are encoded more reliably in certain low-dimensional subspaces. These coding subspaces are defined by correlations between neural activity in the primary sensory cortex and upstream sensory brain regions; the most correlated dimensions were best for decoding. We analytically show that these correlation-based coding subspaces improve, reaching optimal limits (without an ideal observer), as noise correlations between cortex and upstream regions are reduced. We show that this principle generalizes across diverse sensory stimuli in the olfactory system and the visual system of awake mice. Our results demonstrate an algorithm the cortex may use to multiplex different functions, processing sensory input in low-dimensional subspaces separate from other ongoing functions.
Collapse
Affiliation(s)
- Andrea K Barreiro
- Department of Mathematics, Southern Methodist University, Dallas, TX 75275, USA
| | - Antonio J Fontenele
- Department of Physics, UA Integrative Systems Neuroscience, University of Arkansas, Fayetteville, AR 72701, USA
| | - Cheng Ly
- Department of Statistical Sciences and Operations Research, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Prashant C Raju
- Department of Physics, UA Integrative Systems Neuroscience, University of Arkansas, Fayetteville, AR 72701, USA
| | - Shree Hari Gautam
- Department of Physics, UA Integrative Systems Neuroscience, University of Arkansas, Fayetteville, AR 72701, USA
| | - Woodrow L Shew
- Department of Physics, UA Integrative Systems Neuroscience, University of Arkansas, Fayetteville, AR 72701, USA
| |
Collapse
|
35
|
Craft MF, Barreiro AK, Gautam SH, Shew WL, Ly C. Odor modality is transmitted to cortical brain regions from the olfactory bulb. J Neurophysiol 2023; 130:1226-1242. [PMID: 37791383 PMCID: PMC10994644 DOI: 10.1152/jn.00101.2023] [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: 03/09/2023] [Revised: 10/02/2023] [Accepted: 10/02/2023] [Indexed: 10/05/2023] Open
Abstract
Odor perception is the impetus for important animal behaviors with two predominate modes of processing: odors pass through the front of the nose (orthonasal) while inhaling and sniffing, or through the rear (retronasal) during exhalation and while eating. Despite the importance of olfaction for an animal's well-being and that ortho and retro naturally occur, it is unknown how the modality (ortho vs. retro) is even transmitted to cortical brain regions, which could significantly affect how odors are processed and perceived. Using multielectrode array recordings in tracheotomized anesthetized rats, which decouples ortho-retro modality from breathing, we show that mitral cells in rat olfactory bulb can reliably and directly transmit orthonasal versus retronasal modality with ethyl butyrate, a common food odor. Drug manipulations affecting synaptic inhibition via GABAA lead to worse decoding of ortho versus retro, independent of whether overall inhibition increases or decreases, suggesting that the olfactory bulb circuit may naturally favor encoding this important aspect of odors. Detailed data analysis paired with a firing rate model that captures population trends in spiking statistics shows how this circuit can encode odor modality. We have not only demonstrated that ortho/retro information is encoded to downstream brain regions but also used modeling to demonstrate a plausible mechanism for this encoding; due to synaptic adaptation, it is the slower time course of the retronasal stimulation that causes retronasal responses to be stronger and less sensitive to inhibitory drug manipulations than orthonasal responses.NEW & NOTEWORTHY Whether ortho (sniffing odors) versus retro (exhalation and eating) is encoded from the olfactory bulb to other brain areas is not completely known. Using multielectrode array recordings in anesthetized rats, we show that the olfactory bulb transmits this information downstream via spikes. Altering inhibition degrades ortho/retro information on average. We use theory and computation to explain our results, which should have implications on cortical processing considering that only food odors occur retronasally.
Collapse
Affiliation(s)
- Michelle F Craft
- Department of Statistical Sciences and Operations Research, Virginia Commonwealth University, Richmond, Virginia, United States
| | - Andrea K Barreiro
- Department of Mathematics, Southern Methodist University, Dallas, Texas, United States
| | - Shree Hari Gautam
- Department of Physics, University of Arkansas, Fayetteville, Arkansas, United States
| | - Woodrow L Shew
- Department of Physics, University of Arkansas, Fayetteville, Arkansas, United States
| | - Cheng Ly
- Department of Statistical Sciences and Operations Research, Virginia Commonwealth University, Richmond, Virginia, United States
| |
Collapse
|
36
|
Liu P, Gao C, Wu J, Wu T, Zhang Y, Liu C, Sun C, Li A. Negative valence encoding in the lateral entorhinal cortex during aversive olfactory learning. Cell Rep 2023; 42:113204. [PMID: 37804511 DOI: 10.1016/j.celrep.2023.113204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 08/24/2023] [Accepted: 09/19/2023] [Indexed: 10/09/2023] Open
Abstract
Olfactory learning is widely regarded as a substrate for animal survival. The exact brain areas involved in olfactory learning and how they function at various stages during learning remain elusive. Here, we investigate the role of the lateral entorhinal cortex (LEC) and the posterior piriform cortex (PPC), two important olfactory areas, in aversive olfactory learning. We find that the LEC is involved in the acquisition of negative odor value during olfactory fear conditioning, whereas the PPC is involved in the memory-retrieval phase. Furthermore, inhibition of LEC CaMKIIα+ neurons affects fear encoding, fear memory recall, and PPC responses to a conditioned odor. These findings provide direct evidence for the involvement of LEC CaMKIIα+ neurons in negative valence encoding.
Collapse
Affiliation(s)
- Penglai Liu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China
| | - Cheng Gao
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China
| | - Jing Wu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China
| | - Tingting Wu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China
| | - Ying Zhang
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China
| | - Changyu Liu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China
| | - Changcheng Sun
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China.
| | - Anan Li
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China.
| |
Collapse
|
37
|
Srinivasan S, Daste S, Modi MN, Turner GC, Fleischmann A, Navlakha S. Effects of stochastic coding on olfactory discrimination in flies and mice. PLoS Biol 2023; 21:e3002206. [PMID: 37906721 PMCID: PMC10618007 DOI: 10.1371/journal.pbio.3002206] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 08/21/2023] [Indexed: 11/02/2023] Open
Abstract
Sparse coding can improve discrimination of sensory stimuli by reducing overlap between their representations. Two factors, however, can offset sparse coding's benefits: similar sensory stimuli have significant overlap and responses vary across trials. To elucidate the effects of these 2 factors, we analyzed odor responses in the fly and mouse olfactory regions implicated in learning and discrimination-the mushroom body (MB) and the piriform cortex (PCx). We found that neuronal responses fall along a continuum from extremely reliable across trials to extremely variable or stochastic. Computationally, we show that the observed variability arises from noise within central circuits rather than sensory noise. We propose this coding scheme to be advantageous for coarse- and fine-odor discrimination. More reliable cells enable quick discrimination between dissimilar odors. For similar odors, however, these cells overlap and do not provide distinguishing information. By contrast, more unreliable cells are decorrelated for similar odors, providing distinguishing information, though these benefits only accrue with extended training with more trials. Overall, we have uncovered a conserved, stochastic coding scheme in vertebrates and invertebrates, and we identify a candidate mechanism, based on variability in a winner-take-all (WTA) inhibitory circuit, that improves discrimination with training.
Collapse
Affiliation(s)
- Shyam Srinivasan
- Kavli Institute for Brain and Mind, University of California, San Diego, California, United States of America
- Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Simon Daste
- Department of Neuroscience, Division of Biology and Medicine, Brown University, Providence, Rhode Island, United States of America
- Robert J. and Nancy D. Carney Institute for Brain Science, Brown University, Providence, Rhode Island, United States of America
| | - Mehrab N. Modi
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia, United States of America
| | - Glenn C. Turner
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia, United States of America
| | - Alexander Fleischmann
- Department of Neuroscience, Division of Biology and Medicine, Brown University, Providence, Rhode Island, United States of America
- Robert J. and Nancy D. Carney Institute for Brain Science, Brown University, Providence, Rhode Island, United States of America
| | - Saket Navlakha
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| |
Collapse
|
38
|
Trejo DH, Ciuparu A, da Silva PG, Velasquez CM, Rebouillat B, Gross MD, Davis MB, Muresan RC, Albeanu DF. Fast updating feedback from piriform cortex to the olfactory bulb relays multimodal reward contingency signals during rule-reversal. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.12.557267. [PMID: 37745564 PMCID: PMC10515864 DOI: 10.1101/2023.09.12.557267] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
While animals readily adjust their behavior to adapt to relevant changes in the environment, the neural pathways enabling these changes remain largely unknown. Here, using multiphoton imaging, we investigated whether feedback from the piriform cortex to the olfactory bulb supports such behavioral flexibility. To this end, we engaged head-fixed mice in a multimodal rule-reversal task guided by olfactory and auditory cues. Both odor and, surprisingly, the sound cues triggered cortical bulbar feedback responses which preceded the behavioral report. Responses to the same sensory cue were strongly modulated upon changes in stimulus-reward contingency (rule reversals). The re-shaping of individual bouton responses occurred within seconds of the rule-reversal events and was correlated with changes in the behavior. Optogenetic perturbation of cortical feedback within the bulb disrupted the behavioral performance. Our results indicate that the piriform-to-olfactory bulb feedback carries reward contingency signals and is rapidly re-formatted according to changes in the behavioral context.
Collapse
Affiliation(s)
| | - Andrei Ciuparu
- Transylvanian Institute of Neuroscience, Cluj-Napoca, Romania
| | - Pedro Garcia da Silva
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
- current address – Champalimaud Neuroscience Program, Lisbon, Portugal
| | - Cristina M. Velasquez
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
- current address – University of Oxford, UK
| | - Benjamin Rebouillat
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
- current address –École Normale Supérieure, Paris, France
| | | | | | - Raul C. Muresan
- Transylvanian Institute of Neuroscience, Cluj-Napoca, Romania
- STAR-UBB Institute, Babeş-Bolyai University, Cluj-Napoca, Romania
| | - Dinu F. Albeanu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
- School for Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| |
Collapse
|
39
|
Oberle HM, Ford AN, Czarny JE, Rogalla MM, Apostolides PF. Recurrent Circuits Amplify Corticofugal Signals and Drive Feedforward Inhibition in the Inferior Colliculus. J Neurosci 2023; 43:5642-5655. [PMID: 37308295 PMCID: PMC10401644 DOI: 10.1523/jneurosci.0626-23.2023] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 06/02/2023] [Accepted: 06/06/2023] [Indexed: 06/14/2023] Open
Abstract
The inferior colliculus (IC) is a midbrain hub critical for perceiving complex sounds, such as speech. In addition to processing ascending inputs from most auditory brainstem nuclei, the IC receives descending inputs from auditory cortex that control IC neuron feature selectivity, plasticity, and certain forms of perceptual learning. Although corticofugal synapses primarily release the excitatory transmitter glutamate, many physiology studies show that auditory cortical activity has a net inhibitory effect on IC neuron spiking. Perplexingly, anatomy studies imply that corticofugal axons primarily target glutamatergic IC neurons while only sparsely innervating IC GABA neurons. Corticofugal inhibition of the IC may thus occur largely independently of feedforward activation of local GABA neurons. We shed light on this paradox using in vitro electrophysiology in acute IC slices from fluorescent reporter mice of either sex. Using optogenetic stimulation of corticofugal axons, we find that excitation evoked with single light flashes is indeed stronger in presumptive glutamatergic neurons compared with GABAergic neurons. However, many IC GABA neurons fire tonically at rest, such that sparse and weak excitation suffices to significantly increase their spike rates. Furthermore, a subset of glutamatergic IC neurons fire spikes during repetitive corticofugal activity, leading to polysynaptic excitation in IC GABA neurons owing to a dense intracollicular connectivity. Consequently, recurrent excitation amplifies corticofugal activity, drives spikes in IC GABA neurons, and generates substantial local inhibition in the IC. Thus, descending signals engage intracollicular inhibitory circuits despite apparent constraints of monosynaptic connectivity between auditory cortex and IC GABA neurons.SIGNIFICANCE STATEMENT Descending "corticofugal" projections are ubiquitous across mammalian sensory systems, and enable the neocortex to control subcortical activity in a predictive or feedback manner. Although corticofugal neurons are glutamatergic, neocortical activity often inhibits subcortical neuron spiking. How does an excitatory pathway generate inhibition? Here we study the corticofugal pathway from auditory cortex to inferior colliculus (IC), a midbrain hub important for complex sound perception. Surprisingly, cortico-collicular transmission was stronger onto IC glutamatergic compared with GABAergic neurons. However, corticofugal activity triggered spikes in IC glutamate neurons with local axons, thereby generating strong polysynaptic excitation and feedforward spiking of GABAergic neurons. Our results thus reveal a novel mechanism that recruits local inhibition despite limited monosynaptic convergence onto inhibitory networks.
Collapse
Affiliation(s)
- Hannah M Oberle
- Neuroscience Graduate Program
- Department of Otolaryngology, Head & Neck Surgery, Kresge Hearing Research Institute
| | - Alexander N Ford
- Department of Otolaryngology, Head & Neck Surgery, Kresge Hearing Research Institute
| | - Jordyn E Czarny
- Department of Otolaryngology, Head & Neck Surgery, Kresge Hearing Research Institute
| | - Meike M Rogalla
- Department of Otolaryngology, Head & Neck Surgery, Kresge Hearing Research Institute
| | - Pierre F Apostolides
- Department of Otolaryngology, Head & Neck Surgery, Kresge Hearing Research Institute
- Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48109
| |
Collapse
|
40
|
Wu J, Liu P, Geng C, Liu C, Li J, Zhu Q, Li A. Principal neurons in the olfactory cortex mediate bidirectional modulation of seizures. J Physiol 2023; 601:3557-3584. [PMID: 37384845 DOI: 10.1113/jp284731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 06/15/2023] [Indexed: 07/01/2023] Open
Abstract
Although the piriform cortex (PC) has been previously implicated as a critical node for seizure generation and propagation, the underlying neural mechanism has remained unclear. Here, we found increased excitability in PC neurons during amygdala kindling acquisition. Optogenetic or chemogenetic activation of PC pyramidal neurons promoted kindling progression, whereas inhibition of these neurons retarded seizure activities induced by electrical kindling in the amygdala. Furthermore, chemogenetic inhibition of PC pyramidal neurons alleviated the severity of kainic acid-induced acute seizures. These results demonstrate that PC pyramidal neurons bidirectionally modulate seizures in temporal lobe epilepsy, providing evidence for the efficacy of PC pyramidal neurons as a potential therapeutic target for epileptogenesis. KEY POINTS: While the piriform cortex (PC) is an important olfactory centre critically involved in olfactory processing and plays a crucial role in epilepsy due to its close connection with the limbic system, how the PC regulates epileptogenesis is largely unknown. In this study, we evaluated the neuronal activity and the role of pyramidal neurons in the PC in the mouse amygdala kindling model of epilepsy. PC pyramidal neurons are hyperexcited during epileptogenesis. Optogenetic and chemogenetic activation of PC pyramidal neurons significantly promoted seizures in the amygdala kindling model, whereas selective inhibition of these neurons produced an anti-epileptic effect for both electrical kindling and kainic acid-induced acute seizures. The results of the present study indicate that PC pyramidal neurons bidirectionally modulate seizure activity.
Collapse
Affiliation(s)
- Jing Wu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| | - Penglai Liu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| | - Chi Geng
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| | - Changyu Liu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| | - Jiaxin Li
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| | - Qiuju Zhu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| | - Anan Li
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| |
Collapse
|
41
|
Poplawsky AJ, Cover C, Reddy S, Chishti HB, Vazquez A, Fukuda M. Odor-evoked layer-specific fMRI activities in the awake mouse olfactory bulb. Neuroimage 2023; 274:120121. [PMID: 37080347 PMCID: PMC10240534 DOI: 10.1016/j.neuroimage.2023.120121] [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: 01/05/2023] [Revised: 03/22/2023] [Accepted: 04/17/2023] [Indexed: 04/22/2023] Open
Abstract
Awake rodent fMRI is increasingly common over the use of anesthesia since it permits behavioral paradigms and does not confound normal brain function or neurovascular coupling. It is well established that adequate acclimation to the loud fMRI environment and head fixation reduces stress in the rodents and allows for whole brain imaging with little contamination from motion. However, it is unknown whether high-resolution fMRI with increased susceptibility to motion and lower sensitivity can measure small, but spatially discrete, activations in awake mice. To examine this, we used contrast-enhanced cerebral blood volume-weighted (CBVw) fMRI in the mouse olfactory bulb for its enhanced sensitivity and neural specificity. We determined that activation patterns in the glomerular layer to four different odors were spatially distinct and were consistent with previously established histological patterns. In addition, odor-evoked laminar activations were greatest in superficial layers that decreased with laminar depth, similar to previous observations. Interestingly, the fMRI response strengths in the granule cell layer were greater in awake mice than our previous anesthetized rat studies, suggesting that feedback neural activities were intact with wakefulness. We finally determined that fMRI signal changes to repeated odor exposure (i.e., olfactory adaptation) attenuated relatively more in the feedback granule cell layer compared to the input glomerular layer, which is consistent with prior observations. We, therefore, conclude that high-resolution CBVw fMRI can measure odor-specific activation patterns and distinguish changes in laminar activity of head and body restrained awake mice.
Collapse
Affiliation(s)
- Alexander John Poplawsky
- Department of Radiology, University of Pittsburgh, McGowan Institute for Regenerative Medicine Building, 3025 E. Carson St., rm. 159, Pittsburgh, PA, 15203, United States.
| | - Christopher Cover
- Department of Radiology, University of Pittsburgh, McGowan Institute for Regenerative Medicine Building, 3025 E. Carson St., rm. 159, Pittsburgh, PA, 15203, United States; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States
| | - Sujatha Reddy
- Department of Radiology, University of Pittsburgh, McGowan Institute for Regenerative Medicine Building, 3025 E. Carson St., rm. 159, Pittsburgh, PA, 15203, United States
| | - Harris B Chishti
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States
| | - Alberto Vazquez
- Department of Radiology, University of Pittsburgh, McGowan Institute for Regenerative Medicine Building, 3025 E. Carson St., rm. 159, Pittsburgh, PA, 15203, United States; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States
| | - Mitsuhiro Fukuda
- Department of Radiology, University of Pittsburgh, McGowan Institute for Regenerative Medicine Building, 3025 E. Carson St., rm. 159, Pittsburgh, PA, 15203, United States
| |
Collapse
|
42
|
Berners-Lee A, Shtrahman E, Grimaud J, Murthy VN. Experience-dependent evolution of odor mixture representations in piriform cortex. PLoS Biol 2023; 21:e3002086. [PMID: 37098044 PMCID: PMC10129003 DOI: 10.1371/journal.pbio.3002086] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 03/17/2023] [Indexed: 04/26/2023] Open
Abstract
Rodents can learn from exposure to rewarding odors to make better and quicker decisions. The piriform cortex is thought to be important for learning complex odor associations; however, it is not understood exactly how it learns to remember discriminations between many, sometimes overlapping, odor mixtures. We investigated how odor mixtures are represented in the posterior piriform cortex (pPC) of mice while they learn to discriminate a unique target odor mixture against hundreds of nontarget mixtures. We find that a significant proportion of pPC neurons discriminate between the target and all other nontarget odor mixtures. Neurons that prefer the target odor mixture tend to respond with brief increases in firing rate at odor onset compared to other neurons, which exhibit sustained and/or decreased firing. We allowed mice to continue training after they had reached high levels of performance and find that pPC neurons become more selective for target odor mixtures as well as for randomly chosen repeated nontarget odor mixtures that mice did not have to discriminate from other nontargets. These single unit changes during overtraining are accompanied by better categorization decoding at the population level, even though behavioral metrics of mice such as reward rate and latency to respond do not change. However, when difficult ambiguous trial types are introduced, the robustness of the target selectivity is correlated with better performance on the difficult trials. Taken together, these data reveal pPC as a dynamic and robust system that can optimize for both current and possible future task demands at once.
Collapse
Affiliation(s)
- Alice Berners-Lee
- Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, Massachusetts, United States of America
| | - Elizabeth Shtrahman
- Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, Massachusetts, United States of America
| | - Julien Grimaud
- Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, Massachusetts, United States of America
- Cell Engineering Laboratory (CellTechs), Sup'Biotech, Villejuif, France
| | - Venkatesh N Murthy
- Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, Massachusetts, United States of America
| |
Collapse
|
43
|
Nagel K. Olfaction: The smell stops here. Curr Biol 2023; 33:R146-R148. [PMID: 36854272 DOI: 10.1016/j.cub.2023.01.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
A recent study has shown that, in the fly Drosophila, olfactory neurons stop signaling when smells get too strong. This changes the way we think about odor encoding across concentrations.
Collapse
Affiliation(s)
- Katherine Nagel
- New York University School of Medicine, 435 E 30th Street, New York, NY 10016, USA.
| |
Collapse
|
44
|
Gonzalez J, Torterolo P, Tort ABL. Mechanisms and functions of respiration-driven gamma oscillations in the primary olfactory cortex. eLife 2023; 12:e83044. [PMID: 36806332 PMCID: PMC10069865 DOI: 10.7554/elife.83044] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 02/17/2023] [Indexed: 02/22/2023] Open
Abstract
Gamma oscillations are believed to underlie cognitive processes by shaping the formation of transient neuronal partnerships on a millisecond scale. These oscillations are coupled to the phase of breathing cycles in several brain areas, possibly reflecting local computations driven by sensory inputs sampled at each breath. Here, we investigated the mechanisms and functions of gamma oscillations in the piriform (olfactory) cortex of awake mice to understand their dependence on breathing and how they relate to local spiking activity. Mechanistically, we find that respiration drives gamma oscillations in the piriform cortex, which correlate with local feedback inhibition and result from recurrent connections between local excitatory and inhibitory neuronal populations. Moreover, respiration-driven gamma oscillations are triggered by the activation of mitral/tufted cells in the olfactory bulb and are abolished during ketamine/xylazine anesthesia. Functionally, we demonstrate that they locally segregate neuronal assemblies through a winner-take-all computation leading to sparse odor coding during each breathing cycle. Our results shed new light on the mechanisms of gamma oscillations, bridging computation, cognition, and physiology.
Collapse
Affiliation(s)
- Joaquin Gonzalez
- Departamento de Fisiología, Facultad de Medicina, Universidad de la RepúblicaMontevideoUruguay
- Brain Institute, Federal University of Rio Grande do NorteNatalBrazil
| | - Pablo Torterolo
- Departamento de Fisiología, Facultad de Medicina, Universidad de la RepúblicaMontevideoUruguay
| | - Adriano BL Tort
- Brain Institute, Federal University of Rio Grande do NorteNatalBrazil
| |
Collapse
|
45
|
Robust odor identification in novel olfactory environments in mice. Nat Commun 2023; 14:673. [PMID: 36781878 PMCID: PMC9925783 DOI: 10.1038/s41467-023-36346-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 01/26/2023] [Indexed: 02/15/2023] Open
Abstract
Relevant odors signaling food, mates, or predators can be masked by unpredictable mixtures of less relevant background odors. Here, we developed a mouse behavioral paradigm to test the role played by the novelty of the background odors. During the task, mice identified target odors in previously learned background odors and were challenged by catch trials with novel background odors, a task similar to visual CAPTCHA. Female wild-type (WT) mice could accurately identify known targets in novel background odors. WT mice performance was higher than linear classifiers and the nearest neighbor classifier trained using olfactory bulb glomerular activation patterns. Performance was more consistent with an odor deconvolution method. We also used our task to investigate the performance of female Cntnap2-/- mice, which show some autism-like behaviors. Cntnap2-/- mice had glomerular activation patterns similar to WT mice and matched WT mice target detection for known background odors. However, Cntnap2-/- mice performance fell almost to chance levels in the presence of novel backgrounds. Our findings suggest that mice use a robust algorithm for detecting odors in novel environments and this computation is impaired in Cntnap2-/- mice.
Collapse
|
46
|
Riquelme JL, Hemberger M, Laurent G, Gjorgjieva J. Single spikes drive sequential propagation and routing of activity in a cortical network. eLife 2023; 12:e79928. [PMID: 36780217 PMCID: PMC9925052 DOI: 10.7554/elife.79928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 12/19/2022] [Indexed: 02/14/2023] Open
Abstract
Single spikes can trigger repeatable firing sequences in cortical networks. The mechanisms that support reliable propagation of activity from such small events and their functional consequences remain unclear. By constraining a recurrent network model with experimental statistics from turtle cortex, we generate reliable and temporally precise sequences from single spike triggers. We find that rare strong connections support sequence propagation, while dense weak connections modulate propagation reliability. We identify sections of sequences corresponding to divergent branches of strongly connected neurons which can be selectively gated. Applying external inputs to specific neurons in the sparse backbone of strong connections can effectively control propagation and route activity within the network. Finally, we demonstrate that concurrent sequences interact reliably, generating a highly combinatorial space of sequence activations. Our results reveal the impact of individual spikes in cortical circuits, detailing how repeatable sequences of activity can be triggered, sustained, and controlled during cortical computations.
Collapse
Affiliation(s)
- Juan Luis Riquelme
- Max Planck Institute for Brain ResearchFrankfurt am MainGermany
- School of Life Sciences, Technical University of MunichFreisingGermany
| | - Mike Hemberger
- Max Planck Institute for Brain ResearchFrankfurt am MainGermany
| | - Gilles Laurent
- Max Planck Institute for Brain ResearchFrankfurt am MainGermany
| | - Julijana Gjorgjieva
- Max Planck Institute for Brain ResearchFrankfurt am MainGermany
- School of Life Sciences, Technical University of MunichFreisingGermany
| |
Collapse
|
47
|
Wu T, Li S, Du D, Li R, Liu P, Yin Z, Zhang H, Qiao Y, Li A. Olfactory-auditory sensory integration in the lateral entorhinal cortex. Prog Neurobiol 2023; 221:102399. [PMID: 36581184 DOI: 10.1016/j.pneurobio.2022.102399] [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: 08/09/2022] [Revised: 12/02/2022] [Accepted: 12/19/2022] [Indexed: 12/27/2022]
Abstract
Multisensory integration plays an important role in animal cognition. Although many studies have focused on visual-auditory integration, studies on olfactory-auditory integration are rare. Here, we investigated neural activity patterns and odor decoding in the lateral entorhinal cortex (LEC) under uni-sensory and multisensory stimuli in awake, head-fixed mice. Using specific retrograde tracing, we verified that the LEC receives direct inputs from the primary auditory cortex (AC) and the medial geniculate body (MGB). Strikingly, we found that mitral/tufted cells (M/Ts) in the olfactory bulb (OB) and neurons in the LEC respond to both olfactory and auditory stimuli. Sound decreased the neural responses evoked by odors in both the OB and LEC, for both excitatory and inhibitory responses. Interestingly, significant changes in odor decoding performance and modulation of odor-evoked local field potentials (LFPs) were observed only in the LEC. These data indicate that the LEC is a critical center for olfactory-auditory multisensory integration, with direct projections from both olfactory and auditory centers.
Collapse
Affiliation(s)
- Tingting Wu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China; Artificial Auditory Laboratory of Jiangsu Province, Xuzhou Medical University, Xuzhou 221004, China; Clinical Hearing Center, Department of Otorhinolaryngology - Head and Neck Surgery, Affiliated Hospital of Xuzhou Medical University, Xuzhou 221006, China; Department of Otolaryngology, Eye, Ear, Nose and Throat Hospital, Shanghai Key Clinical Disciplines of Otorhinolaryngology, Fudan University, Shanghai 200031, China
| | - Shan Li
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China
| | - Deliang Du
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China; Artificial Auditory Laboratory of Jiangsu Province, Xuzhou Medical University, Xuzhou 221004, China; Clinical Hearing Center, Department of Otorhinolaryngology - Head and Neck Surgery, Affiliated Hospital of Xuzhou Medical University, Xuzhou 221006, China
| | - Ruochen Li
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China
| | - Penglai Liu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China
| | - Zhaoyang Yin
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China
| | - Hongxing Zhang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou 221004, China; Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical University, Xuzhou 221004, China; NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic Drugs, Xuzhou Medical University, Xuzhou 221004, China
| | - Yuehua Qiao
- Artificial Auditory Laboratory of Jiangsu Province, Xuzhou Medical University, Xuzhou 221004, China; Clinical Hearing Center, Department of Otorhinolaryngology - Head and Neck Surgery, Affiliated Hospital of Xuzhou Medical University, Xuzhou 221006, China.
| | - Anan Li
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China.
| |
Collapse
|
48
|
Bolding KA, Franks KM. Electrophysiological Recordings from Identified Cell Types in the Olfactory Cortex of Awake Mice. Methods Mol Biol 2023; 2710:209-221. [PMID: 37688735 DOI: 10.1007/978-1-0716-3425-7_16] [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] [Indexed: 09/11/2023]
Abstract
Neural circuits consist of a myriad of distinct cell types, each with specific intrinsic properties and patterns of synaptic connectivity, which transform neural input and convey this information to downstream targets. Understanding how different features of an odor stimulus are encoded and relayed to their appropriate targets will require selective identification and manipulation of these different elements of the circuit. Here, we describe methods to obtain dense, extracellular electrophysiological recordings of odor-evoked activity in olfactory (piriform) cortex of awake, head-fixed mice, and optogenetic tools and procedures to identify genetically defined cell types within this circuit.
Collapse
Affiliation(s)
- Kevin A Bolding
- Department of Neurobiology, Duke University, Durham, NC, USA
- Monell Chemical Senses Center, Philadelphia, PA, USA
- Department of Neuroscience, University of Pennsylvania, Philadelphia, PA, USA
| | - Kevin M Franks
- Department of Neurobiology, Duke University, Durham, NC, USA.
| |
Collapse
|
49
|
Idris A, Christensen BA, Walker EM, Maier JX. Multisensory integration of orally-sourced gustatory and olfactory inputs to the posterior piriform cortex in awake rats. J Physiol 2023; 601:151-169. [PMID: 36385245 PMCID: PMC9869978 DOI: 10.1113/jp283873] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 11/09/2022] [Indexed: 11/18/2022] Open
Abstract
Flavour refers to the sensory experience of food, which is a combination of sensory inputs sourced from multiple modalities during consumption, including taste and odour. Previous work has demonstrated that orally-sourced taste and odour cues interact to determine perceptual judgements of flavour stimuli, although the underlying cellular- and circuit-level neural mechanisms remain unknown. We recently identified a region of the piriform olfactory cortex in rats that responds to both taste and odour stimuli. Here, we investigated how converging taste and odour inputs to this area interact to affect single neuron responsiveness ensemble coding of flavour identity. To accomplish this, we recorded spiking activity from ensembles of single neurons in the posterior piriform cortex (pPC) in awake, tasting rats while delivering taste solutions, odour solutions and taste + odour mixtures directly into the oral cavity. Our results show that taste and odour inputs evoke highly selective, temporally-overlapping responses in multisensory pPC neurons. Comparing responses to mixtures and their unisensory components revealed that taste and odour inputs interact in a non-linear manner to produce unique response patterns. Taste input enhances trial-by-trial decoding of odour identity from small ensembles of simultaneously recorded neurons. Together, these results demonstrate that taste and odour inputs to pPC interact in complex, non-linear ways to form amodal flavour representations that enhance identity coding. KEY POINTS: Experience of food involves taste and smell, although how information from these different senses is combined by the brain to create our sense of flavour remains unknown. We recorded from small groups of neurons in the olfactory cortex of awake rats while they consumed taste solutions, odour solutions and taste + odour mixtures. Taste and smell solutions evoke highly selective responses. When presented in a mixture, taste and smell inputs interacted to alter responses, resulting in activation of unique sets of neurons that could not be predicted by the component responses. Synergistic interactions increase discriminability of odour representations. The olfactory cortex uses taste and smell to create new information representing multisensory flavour identity.
Collapse
Affiliation(s)
- Ammar Idris
- Department of Neurobiology & AnatomyWake Forest School of MedicineWinston‐SalemNCUSA
| | - Brooke A. Christensen
- Department of Neurobiology & AnatomyWake Forest School of MedicineWinston‐SalemNCUSA
| | - Ellen M. Walker
- Department of Neurobiology & AnatomyWake Forest School of MedicineWinston‐SalemNCUSA
| | - Joost X. Maier
- Department of Neurobiology & AnatomyWake Forest School of MedicineWinston‐SalemNCUSA
| |
Collapse
|
50
|
Chae H, Banerjee A, Dussauze M, Albeanu DF. Long-range functional loops in the mouse olfactory system and their roles in computing odor identity. Neuron 2022; 110:3970-3985.e7. [PMID: 36174573 PMCID: PMC9742324 DOI: 10.1016/j.neuron.2022.09.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 07/12/2022] [Accepted: 09/02/2022] [Indexed: 12/15/2022]
Abstract
Elucidating the neural circuits supporting odor identification remains an open challenge. Here, we analyze the contribution of the two output cell types of the mouse olfactory bulb (mitral and tufted cells) to decode odor identity and concentration and its dependence on top-down feedback from their respective major cortical targets: piriform cortex versus anterior olfactory nucleus. We find that tufted cells substantially outperform mitral cells in decoding both odor identity and intensity. Cortical feedback selectively regulates the activity of its dominant bulb projection cell type and implements different computations. Piriform feedback specifically restructures mitral responses, whereas feedback from the anterior olfactory nucleus preferentially controls the gain of tufted representations without altering their odor tuning. Our results identify distinct functional loops involving the mitral and tufted cells and their cortical targets. We suggest that in addition to the canonical mitral-to-piriform pathway, tufted cells and their target regions are ideally positioned to compute odor identity.
Collapse
Affiliation(s)
- Honggoo Chae
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Arkarup Banerjee
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA; Cold Spring Harbor Laboratory School for Biological Sciences, Cold Spring Harbor, NY, USA
| | - Marie Dussauze
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA; Cold Spring Harbor Laboratory School for Biological Sciences, Cold Spring Harbor, NY, USA
| | - Dinu F Albeanu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA; Cold Spring Harbor Laboratory School for Biological Sciences, Cold Spring Harbor, NY, USA.
| |
Collapse
|