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Li W, Wilson DA. Threat Memory in the Sensory Cortex: Insights from Olfaction. Neuroscientist 2024; 30:285-293. [PMID: 36703569 DOI: 10.1177/10738584221148994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The amygdala has long held the center seat in the neural basis of threat conditioning. However, a rapidly growing literature has elucidated extra-amygdala circuits in this process, highlighting the sensory cortex for its critical role in the mnemonic aspect of the process. While this literature is largely focused on the auditory system, substantial human and rodent findings on the olfactory system have emerged. The unique nature of the olfactory neuroanatomy and its intimate association with emotion compels a review of this recent literature to illuminate its special contribution to threat memory. Here, integrating recent evidence in humans and animal models, we posit that the olfactory (piriform) cortex is a primary and necessary component of the distributed threat memory network, supporting mnemonic ensemble coding of acquired threat. We further highlight the basic circuit architecture of the piriform cortex characterized by distributed, auto-associative connections, which is prime for highly efficient content-addressable memory computing to support threat memory. Given the primordial role of the piriform cortex in cortical evolution and its simple, well-defined circuits, we propose that olfaction can be a model system for understanding (transmodal) sensory cortical mechanisms underlying threat memory.
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Affiliation(s)
- Wen Li
- Department of Psychology, Florida State University, Tallahassee, FL, USA
| | - Donald A Wilson
- Department of Child & Adolescent Psychiatry, New York University School of Medicine, New York, NY, USA
- Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, USA
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2
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Kundu S, Paul B, Reuevni I, Lamprecht R, Barkai E. Learning-induced bidirectional enhancement of inhibitory synaptic metaplasticity. J Physiol 2024; 602:2343-2358. [PMID: 38654583 DOI: 10.1113/jp284761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 04/02/2024] [Indexed: 04/26/2024] Open
Abstract
Training rodents in a particularly difficult olfactory-discrimination (OD) task results in the acquisition of the ability to perform the task well, termed 'rule learning'. In addition to enhanced intrinsic excitability and synaptic excitation in piriform cortex pyramidal neurons, rule learning results in increased synaptic inhibition across the whole cortical network to the point where it precisely maintains the balance between inhibition and excitation. The mechanism underlying such precise inhibitory enhancement remains to be explored. Here, we use brain slices from transgenic mice (VGAT-ChR2-EYFP), enabling optogenetic stimulation of single GABAergic neurons and recordings of unitary synaptic events in pyramidal neurons. Quantal analysis revealed that learning-induced enhanced inhibition is mediated by increased quantal size of the evoked inhibitory events. Next, we examined the plasticity of synaptic inhibition induced by long-lasting, intrinsically evoked spike firing in post-synaptic neurons. Repetitive depolarizing current pulses from depolarized (-70 mV) or hyperpolarized (-90 mV) membrane potentials induced long-term depression (LTD) and long-term potentiation (LTP) of synaptic inhibition, respectively. We found a profound bidirectional increase in the ability to induce both LTD, mediated by L-type calcium channels, and LTP, mediated by R-type calcium channels after rule learning. Blocking the GABAB receptor reversed the effect of intrinsic stimulation at -90 mV from LTP to LTD. We suggest that learning greatly enhances the ability to modify the strength of synaptic inhibition of principal neurons in both directions. Such plasticity of synaptic plasticity allows fine-tuning of inhibition on each particular neuron, thereby stabilizing the network while maintaining the memory of the rule. KEY POINTS: Olfactory discrimination rule learning results in long-lasting enhancement of synaptic inhibition on piriform cortex pyramidal neurons. Quantal analysis of unitary inhibitory synaptic events, evoked by optogenetic minimal stimulation, revealed that enhanced synaptic inhibition is mediated by increased quantal size. Surprisingly, metaplasticity of synaptic inhibition, induced by intrinsically evoked repetitive spike firing, is increased bidirectionally. The susceptibility to both long-term depression (LTD) and long-term potentiation (LTP) of inhibition is enhanced after learning. LTD of synaptic inhibition is mediated by L-type calcium channels and LTP by R-type calcium channels. LTP is also dependent on activation of GABAB receptors. We suggest that learning-induced changes in the metaplasticity of synaptic inhibition enable the fine-tuning of inhibition on each particular neuron, thereby stabilizing the network while maintaining the memory of the rule.
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Affiliation(s)
- Sankhanava Kundu
- Sagol Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
| | - Blesson Paul
- Sagol Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
| | - Iris Reuevni
- Sagol Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
| | - Raphael Lamprecht
- Sagol Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
| | - Edi Barkai
- Sagol Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
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3
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Fang S, Luo Z, Wei Z, Qin Y, Zheng J, Zhang H, Jin J, Li J, Miao C, Yang S, Li Y, Liang Z, Yu XD, Zhang XM, Xiong W, Zhu H, Gan WB, Huang L, Li B. Sexually dimorphic control of affective state processing and empathic behaviors. Neuron 2024; 112:1498-1517.e8. [PMID: 38430912 DOI: 10.1016/j.neuron.2024.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Revised: 12/08/2023] [Accepted: 02/01/2024] [Indexed: 03/05/2024]
Abstract
Recognizing the affective states of social counterparts and responding appropriately fosters successful social interactions. However, little is known about how the affective states are expressed and perceived and how they influence social decisions. Here, we show that male and female mice emit distinct olfactory cues after experiencing distress. These cues activate distinct neural circuits in the piriform cortex (PiC) and evoke sexually dimorphic empathic behaviors in observers. Specifically, the PiC → PrL pathway is activated in female observers, inducing a social preference for the distressed counterpart. Conversely, the PiC → MeA pathway is activated in male observers, evoking excessive self-grooming behaviors. These pathways originate from non-overlapping PiC neuron populations with distinct gene expression signatures regulated by transcription factors and sex hormones. Our study unveils how internal states of social counterparts are processed through sexually dimorphic mechanisms at the molecular, cellular, and circuit levels and offers insights into the neural mechanisms underpinning sex differences in higher brain functions.
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Affiliation(s)
- Shunchang Fang
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Zhengyi Luo
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Zicheng Wei
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Yuxin Qin
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Jieyan Zheng
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Hongyang Zhang
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Jianhua Jin
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Jiali Li
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Chenjian Miao
- Institute on Aging, Hefei, China and Brain Disorders, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China
| | - Shana Yang
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Yonglin Li
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Zirui Liang
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Xiao-Dan Yu
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Xiao Min Zhang
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Wei Xiong
- Institute on Aging, Hefei, China and Brain Disorders, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China
| | - Hongying Zhu
- Institute on Aging, Hefei, China and Brain Disorders, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China
| | | | - Lianyan Huang
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China; Key Laboratory of Human Microbiome and Chronic Diseases (Sun Yat-Sen University), Ministry of Education, Guangzhou 510655, China.
| | - Boxing Li
- Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China; Advanced Medical Technology Center, the First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, China; Key Laboratory of Human Microbiome and Chronic Diseases (Sun Yat-Sen University), Ministry of Education, Guangzhou 510655, China.
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4
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Okumura T, Kida I, Yokoi A, Nakai T, Nishimoto S, Touhara K, Okamoto M. Semantic context-dependent neural representations of odors in the human piriform cortex revealed by 7T MRI. Hum Brain Mapp 2024; 45:e26681. [PMID: 38656060 PMCID: PMC11041378 DOI: 10.1002/hbm.26681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 03/23/2024] [Accepted: 03/28/2024] [Indexed: 04/26/2024] Open
Abstract
Olfactory perception depends not only on olfactory inputs but also on semantic context. Although multi-voxel activity patterns of the piriform cortex, a part of the primary olfactory cortex, have been shown to represent odor perception, it remains unclear whether semantic contexts modulate odor representation in this region. Here, we investigated whether multi-voxel activity patterns in the piriform cortex change when semantic context modulates odor perception and, if so, whether the modulated areas communicate with brain regions involved in semantic and memory processing beyond the piriform cortex. We also explored regional differences within the piriform cortex, which are influenced by olfactory input and semantic context. We used 2 × 2 combinations of word labels and odorants that were perceived as congruent and measured piriform activity with a 1-mm isotropic resolution using 7T MRI. We found that identical odorants labeled with different words were perceived differently. This labeling effect was observed in multi-voxel activity patterns in the piriform cortex, as the searchlight decoding analysis distinguished identical odors with different labels for half of the examined stimulus pairs. Significant functional connectivity was observed between parts of the piriform cortex that were modulated by labels and regions associated with semantic and memory processing. While the piriform multi-voxel patterns evoked by different olfactory inputs were also distinguishable, the decoding accuracy was significant for only one stimulus pair, preventing definitive conclusions regarding the locational differences between areas influenced by word labels and olfactory inputs. These results suggest that multi-voxel patterns of piriform activity can be modulated by semantic context, possibly due to communication between the piriform cortex and the semantic and memory regions.
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Affiliation(s)
- Toshiki Okumura
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of TokyoTokyoJapan
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT)OsakaJapan
| | - Ikuhiro Kida
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT)OsakaJapan
- Graduate School of Frontier Biosciences, Osaka UniversityOsakaJapan
| | - Atsushi Yokoi
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT)OsakaJapan
- Graduate School of Frontier Biosciences, Osaka UniversityOsakaJapan
| | - Tomoya Nakai
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT)OsakaJapan
| | - Shinji Nishimoto
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT)OsakaJapan
- Graduate School of Frontier Biosciences, Osaka UniversityOsakaJapan
| | - Kazushige Touhara
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of TokyoTokyoJapan
- International Research Center for Neurointelligence (WPI‐IRCN), Institutes for Advanced Study, The University of TokyoTokyoJapan
| | - Masako Okamoto
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of TokyoTokyoJapan
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5
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Zhao Y, Bhutani S, Kahnt T. Appetite-regulating hormones modulate odor perception and odor-evoked activity in hypothalamus and olfactory cortices. Chem Senses 2023; 48:bjad039. [PMID: 37796827 PMCID: PMC10590159 DOI: 10.1093/chemse/bjad039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Indexed: 10/07/2023] Open
Abstract
Odors guide food seeking, and food intake modulates olfactory function. This interaction is mediated by appetite-regulating hormones like ghrelin, insulin, and leptin, which alter activity in the rodent olfactory bulb, but their effects on downstream olfactory cortices have not yet been established in humans. The olfactory tract connects the olfactory bulb to the cortex through 3 main striae, terminating in the piriform cortex (PirC), amygdala (AMY), olfactory tubercule (OT), and anterior olfactory nucleus (AON). Here, we test the hypothesis that appetite-regulating hormones modulate olfactory processing in the endpoints of the olfactory tract and the hypothalamus. We collected odor-evoked functional magnetic resonance imaging (fMRI) responses and plasma levels of ghrelin, insulin, and leptin from human subjects (n = 25) after a standardized meal. We found that a hormonal composite measure, capturing variance relating positively to insulin and negatively to ghrelin, correlated inversely with odor intensity ratings and fMRI responses to odorized vs. clean air in the hypothalamus, OT, and AON. No significant correlations were found with activity in PirC or AMY, the endpoints of the lateral stria. Exploratory whole-brain analyses revealed significant correlations near the diagonal band of Broca and parahippocampal gyrus. These results demonstrate that high (low) blood plasma concentrations of insulin (ghrelin) decrease perceived odor intensity and odor-evoked activity in the cortical targets of the medial and intermediate striae of the olfactory tract, as well as the hypothalamus. These findings expand our understanding of the cortical mechanisms by which metabolic hormones in humans modulate olfactory processing after a meal.
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Affiliation(s)
- Yao Zhao
- National Institute on Drug Abuse Intramural Research Program, Cellular and Neurocomputational Systems Branch, Baltimore, MD,United States
| | - Surabhi Bhutani
- San Diego State University, School of Exercise and Nutritional Sciences, San Diego, CA, United States
| | - Thorsten Kahnt
- National Institute on Drug Abuse Intramural Research Program, Cellular and Neurocomputational Systems Branch, Baltimore, MD,United States
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6
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Ngo FY, Li H, Zhang H, Lau CYG. Acute Fasting Modulates Food-Seeking Behavior and Neural Signaling in the Piriform Cortex. Nutrients 2022; 14:nu14194156. [PMID: 36235808 PMCID: PMC9572926 DOI: 10.3390/nu14194156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/01/2022] [Accepted: 10/03/2022] [Indexed: 11/16/2022] Open
Abstract
It is well known that the state of hunger can modulate hormones and hypothalamic neural circuits to drive food-seeking behavior and consumption. However, the role the sensory cortex plays in regulating foraging is much less explored. Here, we investigated whether acute fasting in mice can alter an odor-guided foraging behavior and how it can alter neurons and synapses in the (olfactory) piriform cortex (PC). Acute hunger enhances the motivation of a mouse to search for food pellets and increases food intake. The foraging behavior strongly activates the PC, as revealed by c-Fos immunostaining. The activation of PC is accompanied by an increase in excitation-inhibition ratio of synaptic density. Fasting also enhances the phosphorylation of AMP kinase, a biochemical energy regulator. Taken together, our results uncover a new regulatory brain region and implicate the PC in controlling foraging behavior.
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Affiliation(s)
- Fung-Yin Ngo
- Department of Neuroscience, City University of Hong Kong, Hong Kong, China
- Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, China
| | - Huanhuan Li
- Department of Neuroscience, City University of Hong Kong, Hong Kong, China
- Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, China
| | - Huiqi Zhang
- Department of Neuroscience, City University of Hong Kong, Hong Kong, China
- Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, China
| | - Chun-Yue Geoffrey Lau
- Department of Neuroscience, City University of Hong Kong, Hong Kong, China
- Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, China
- Correspondence: ; Tel.: +852-3442-4345
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7
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Endo K, Kazama H. Central organization of a high-dimensional odor space. Curr Opin Neurobiol 2022. [PMID: 35367860 DOI: 10.1016/j.conb.2022.10252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Animals recognize groups and mixtures of odors as a unitary object. This ability is crucial to generalize known odors to newly encountered ones despite variations. However, it remains largely unknown how multitudes of odors are represented and organized in the higher brain regions to support odor object recognition. Here we discuss recent advances uncovering the population odor responses in the rodent piriform cortex and the Drosophila mushroom body, and highlight the emerging principles on the organization, mechanism, stereotypy, and experience-dependence of central odor representations.
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Affiliation(s)
- Keita Endo
- RIKEN Center for Brain Science, Wako, Japan
| | - Hokto Kazama
- RIKEN Center for Brain Science, Wako, Japan; RIKEN CBS-KAO Collaboration Center, Wako, Japan; Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.
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8
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East BS, Fleming G, Vervoordt S, Shah P, Sullivan RM, Wilson DA. Basolateral amygdala to posterior piriform cortex connectivity ensures precision in learned odor threat. Sci Rep 2021; 11:21746. [PMID: 34741138 PMCID: PMC8571329 DOI: 10.1038/s41598-021-01320-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 10/20/2021] [Indexed: 12/24/2022] Open
Abstract
Odor perception can both evoke emotional states and be shaped by emotional or hedonic states. The amygdala complex plays an important role in recognition of, and response to, hedonically valenced stimuli, and has strong, reciprocal connectivity with the primary olfactory (piriform) cortex. Here, we used differential odor-threat conditioning in rats to test the role of basolateral amygdala (BLA) input to the piriform cortex in acquisition and expression of learned olfactory threat responses. Using local field potential recordings, we demonstrated that functional connectivity (high gamma band coherence) between the BLA and posterior piriform cortex (pPCX) is enhanced after differential threat conditioning. Optogenetic suppression of activity within the BLA prevents learned threat acquisition, as do lesions of the pPCX prior to threat conditioning (without inducing anosmia), suggesting that both regions are critical for acquisition of learned odor threat responses. However, optogenetic BLA suppression during testing did not impair threat response to the CS+ , but did induce generalization to the CS-. A similar loss of stimulus control and threat generalization was induced by selective optogenetic suppression of BLA input to pPCX. These results suggest an important role for amygdala-sensory cortical connectivity in shaping responses to threatening stimuli.
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Affiliation(s)
- Brett S East
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
- Child and Adolescent Psychiatry, New York University Langone Medical Center, 1 Park Avenue, 7th Floor, New York, NY, 10016, USA
| | - Gloria Fleming
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Samantha Vervoordt
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Prachi Shah
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Regina M Sullivan
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
- Child and Adolescent Psychiatry, New York University Langone Medical Center, 1 Park Avenue, 7th Floor, New York, NY, 10016, USA
| | - Donald A Wilson
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA.
- Child and Adolescent Psychiatry, New York University Langone Medical Center, 1 Park Avenue, 7th Floor, New York, NY, 10016, USA.
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Coviello S, Benedetti B, Jakubecova D, Belles M, Klimczak P, Gramuntell Y, Couillard-Despres S, Nacher J. PSA Depletion Induces the Differentiation of Immature Neurons in the Piriform Cortex of Adult Mice. Int J Mol Sci 2021; 22:5733. [PMID: 34072166 PMCID: PMC8198564 DOI: 10.3390/ijms22115733] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/10/2021] [Accepted: 05/11/2021] [Indexed: 12/12/2022] Open
Abstract
Immature neurons are maintained in cortical regions of the adult mammalian brain. In rodents, many of these immature neurons can be identified in the piriform cortex based on their high expression of early neuronal markers, such as doublecortin (DCX) and the polysialylated form of the neural cell adhesion molecule (PSA-NCAM). This molecule plays critical roles in different neurodevelopmental events. Taking advantage of a DCX-CreERT2/Flox-EGFP reporter mice, we investigated the impact of targeted PSA enzymatic depletion in the piriform cortex on the fate of immature neurons. We report here that the removal of PSA accelerated the final development of immature neurons. This was revealed by a higher frequency of NeuN expression, an increase in the number of cells carrying an axon initial segment (AIS), and an increase in the number of dendrites and dendritic spines on the immature neurons. Taken together, our results demonstrated the crucial role of the PSA moiety in the protracted development of immature neurons residing outside of the neurogenic niches. More studies will be required to understand the intrinsic and extrinsic factors affecting PSA-NCAM expression to understand how the brain regulates the incorporation of these immature neurons to the established neuronal circuits of the adult brain.
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Affiliation(s)
- Simona Coviello
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, 46100 Burjassot, Spain; (S.C.); (M.B.); (P.K.); (Y.G.)
| | - Bruno Benedetti
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Institute of Experimental Neuroregeneration, Paracelsus Medical University, 5020 Salzburg, Austria; (B.B.); (D.J.)
- Austrian Cluster for Tissue Regeneration, 1200 Vienna, Austria
| | - Dominika Jakubecova
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Institute of Experimental Neuroregeneration, Paracelsus Medical University, 5020 Salzburg, Austria; (B.B.); (D.J.)
| | - Maria Belles
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, 46100 Burjassot, Spain; (S.C.); (M.B.); (P.K.); (Y.G.)
| | - Patrycja Klimczak
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, 46100 Burjassot, Spain; (S.C.); (M.B.); (P.K.); (Y.G.)
| | - Yaiza Gramuntell
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, 46100 Burjassot, Spain; (S.C.); (M.B.); (P.K.); (Y.G.)
| | - Sebastien Couillard-Despres
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Institute of Experimental Neuroregeneration, Paracelsus Medical University, 5020 Salzburg, Austria; (B.B.); (D.J.)
- Austrian Cluster for Tissue Regeneration, 1200 Vienna, Austria
| | - Juan Nacher
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, 46100 Burjassot, Spain; (S.C.); (M.B.); (P.K.); (Y.G.)
- Spanish National Network for Research in Mental Health (CIBERSAM), 28029 Madrid, Spain
- Fundación Investigación Hospital Clínico de Valencia, INCLIVA, 46010 Valencia, Spain
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10
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Shabangu T, Chen HL, Zhuang ZH, Pierani A, Chen CFF, Chou SJ. Specific contribution of neurons from the Dbx1 lineage to the piriform cortex. Sci Rep 2021; 11:8349. [PMID: 33863910 PMCID: PMC8052341 DOI: 10.1038/s41598-021-86512-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 03/15/2021] [Indexed: 11/20/2022] Open
Abstract
The piriform cortex (PC) is a major cortical processing center for the sense of smell that receives direct inputs from the olfactory bulb. In mice, the PC consists of three neuronal layers, which are populated by cells with distinct developmental origins. One origin of PC neurons is the pool of Dbx1-expressing neural progenitors located in the ventral pallium at the pallial-subpallial boundary. Since the precise mechanisms of PC neuron development are largely unknown, we sought to define the distribution, timing of neurogenesis, morphology and projection patterns of PC neurons from the Dbx1 lineage. We found that Dbx1-lineage neurons are preferentially distributed in layer 2 and enriched in the ventral portion of the PC. Further, Dbx1 neurons are early-born neurons and contribute to most neuronal subtypes in the PC. Our data also revealed an enrichment of Dbx1-lineage neurons in the ventral anterior PC that project to the orbitofrontal cortex. These findings suggest a specific association between the developmental origin of PC neurons and their neuronal properties.
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Affiliation(s)
- Thando Shabangu
- Molecular Cell Biology, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Hung-Lun Chen
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Zi-Hui Zhuang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Alessandra Pierani
- Imagine Institute, Team Genetics and Development of the Cerebral Cortex, Université de Paris, F-75015, Paris, France
- Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, Université de Paris, F-75014, Paris, France
| | - Chien-Fu F Chen
- Molecular Cell Biology, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan.
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan.
| | - Shen-Ju Chou
- Molecular Cell Biology, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan.
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan.
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan.
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11
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Lötsch J, Oertel BG, Felden L, Nöth U, Deichmann R, Hummel T, Walter C. Central encoding of the strength of intranasal chemosensory trigeminal stimuli in a human experimental pain setting. Hum Brain Mapp 2020; 41:5240-5254. [PMID: 32870583 PMCID: PMC7670645 DOI: 10.1002/hbm.25190] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 08/10/2020] [Accepted: 08/11/2020] [Indexed: 12/29/2022] Open
Abstract
An important measure in pain research is the intensity of nociceptive stimuli and their cortical representation. However, there is evidence of different cerebral representations of nociceptive stimuli, including the fact that cortical areas recruited during processing of intranasal nociceptive chemical stimuli included those outside the traditional trigeminal areas. Therefore, the aim of this study was to investigate the major cerebral representations of stimulus intensity associated with intranasal chemical trigeminal stimulation. Trigeminal stimulation was achieved with carbon dioxide presented to the nasal mucosa. Using a single-blinded, randomized crossover design, 24 subjects received nociceptive stimuli with two different stimulation paradigms, depending on the just noticeable differences in the stimulus strengths applied. Stimulus-related brain activations were recorded using functional magnetic resonance imaging with event-related design. Brain activations increased significantly with increasing stimulus intensity, with the largest cluster at the right Rolandic operculum and a global maximum in a smaller cluster at the left lower frontal orbital lobe. Region of interest analyses additionally supported an activation pattern correlated with the stimulus intensity at the piriform cortex as an area of special interest with the trigeminal input. The results support the piriform cortex, in addition to the secondary somatosensory cortex, as a major area of interest for stimulus strength-related brain activation in pain models using trigeminal stimuli. This makes both areas a primary objective to be observed in human experimental pain settings where trigeminal input is used to study effects of analgesics.
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Affiliation(s)
- Jörn Lötsch
- Institute of Clinical PharmacologyGoethe – UniversityFrankfurt am MainGermany
- Fraunhofer Institute for Molecular Biology and Applied Ecology IMEBranch for Translational Medicine and Pharmacology TMPFrankfurt am MainGermany
| | - Bruno G. Oertel
- Institute of Clinical PharmacologyGoethe – UniversityFrankfurt am MainGermany
| | - Lisa Felden
- Institute of Clinical PharmacologyGoethe – UniversityFrankfurt am MainGermany
| | - Ulrike Nöth
- Brain Imaging CenterGoethe – UniversityFrankfurt am MainGermany
| | - Ralf Deichmann
- Brain Imaging CenterGoethe – UniversityFrankfurt am MainGermany
| | - Thomas Hummel
- Smell & Taste Clinic, Department of OtorhinolaryngologyTU DresdenDresdenGermany
| | - Carmen Walter
- Institute of Clinical PharmacologyGoethe – UniversityFrankfurt am MainGermany
- Fraunhofer Institute for Molecular Biology and Applied Ecology IMEBranch for Translational Medicine and Pharmacology TMPFrankfurt am MainGermany
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12
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Wang PY, Boboila C, Chin M, Higashi-Howard A, Shamash P, Wu Z, Stein NP, Abbott LF, Axel R. Transient and Persistent Representations of Odor Value in Prefrontal Cortex. Neuron 2020; 108:209-224.e6. [PMID: 32827456 DOI: 10.1016/j.neuron.2020.07.033] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 03/10/2020] [Accepted: 07/24/2020] [Indexed: 11/19/2022]
Abstract
The representation of odor in olfactory cortex (piriform) is distributive and unstructured and can only be afforded behavioral significance upon learning. We performed 2-photon imaging to examine the representation of odors in piriform and in two downstream areas, the orbitofrontal cortex (OFC) and the medial prefrontal cortex (mPFC), as mice learned olfactory associations. In piriform, we observed that odor responses were largely unchanged during learning. In OFC, 30% of the neurons acquired robust responses to conditioned stimuli (CS+) after learning, and these responses were gated by internal state and task context. Moreover, direct projections from piriform to OFC can be entrained to elicit learned olfactory behavior. CS+ responses in OFC diminished with continued training, whereas persistent representations of both CS+ and CS- odors emerged in mPFC. Optogenetic silencing indicates that these two brain structures function sequentially to consolidate the learning of appetitive associations.
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Affiliation(s)
- Peter Y Wang
- The Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA
| | - Cristian Boboila
- The Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA
| | - Matthew Chin
- The Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA
| | - Alexandra Higashi-Howard
- The Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA; Howard Hughes Medical Institute, Columbia University, New York, NY 10027, USA
| | - Philip Shamash
- The Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA
| | - Zheng Wu
- The Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA
| | - Nicole P Stein
- The Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA
| | - L F Abbott
- The Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA
| | - Richard Axel
- The Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA; Howard Hughes Medical Institute, Columbia University, New York, NY 10027, USA.
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13
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Bolding KA, Nagappan S, Han BX, Wang F, Franks KM. Recurrent circuitry is required to stabilize piriform cortex odor representations across brain states. eLife 2020; 9:e53125. [PMID: 32662420 PMCID: PMC7360366 DOI: 10.7554/elife.53125] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 06/19/2020] [Indexed: 11/13/2022] Open
Abstract
Pattern completion, or the ability to retrieve stable neural activity patterns from noisy or partial cues, is a fundamental feature of memory. Theoretical studies indicate that recurrently connected auto-associative or discrete attractor networks can perform this process. Although pattern completion and attractor dynamics have been observed in various recurrent neural circuits, the role recurrent circuitry plays in implementing these processes remains unclear. In recordings from head-fixed mice, we found that odor responses in olfactory bulb degrade under ketamine/xylazine anesthesia while responses immediately downstream, in piriform cortex, remain robust. Recurrent connections are required to stabilize cortical odor representations across states. Moreover, piriform odor representations exhibit attractor dynamics, both within and across trials, and these are also abolished when recurrent circuitry is eliminated. Here, we present converging evidence that recurrently-connected piriform populations stabilize sensory representations in response to degraded inputs, consistent with an auto-associative function for piriform cortex supported by recurrent circuitry.
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Affiliation(s)
- Kevin A Bolding
- Department of Neurobiology, Duke University Medical SchoolDurhamUnited States
| | | | - Bao-Xia Han
- Department of Neurobiology, Duke University Medical SchoolDurhamUnited States
| | - Fan Wang
- Department of Neurobiology, Duke University Medical SchoolDurhamUnited States
| | - Kevin M Franks
- Department of Neurobiology, Duke University Medical SchoolDurhamUnited States
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14
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Arabkheradmand G, Zhou G, Noto T, Yang Q, Schuele SU, Parvizi J, Gottfried JA, Wu S, Rosenow JM, Koubeissi MZ, Lane G, Zelano C. Anticipation-induced delta phase reset improves human olfactory perception. PLoS Biol 2020; 18:e3000724. [PMID: 32453719 PMCID: PMC7250403 DOI: 10.1371/journal.pbio.3000724] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 04/24/2020] [Indexed: 12/19/2022] Open
Abstract
Anticipating an odor improves detection and perception, yet the underlying neural mechanisms of olfactory anticipation are not well understood. In this study, we used human intracranial electroencephalography (iEEG) to show that anticipation resets the phase of delta oscillations in piriform cortex prior to odor arrival. Anticipatory phase reset correlates with ensuing odor-evoked theta power and improvements in perceptual accuracy. These effects were consistently present in each individual subject and were not driven by potential confounds of pre-inhale motor preparation or power changes. Together, these findings suggest that states of anticipation enhance olfactory perception through phase resetting of delta oscillations in piriform cortex. Use of human intracranial electroencephalography methods, including rare direct recordings from human olfactory cortex, shows that anticipation of odor resets the phase of delta oscillations prior to the arrival of an odor.
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Affiliation(s)
- Ghazaleh Arabkheradmand
- Northwestern University Feinberg School of Medicine, Department of Neurology, Chicago, Illinois, United States of America
| | - Guangyu Zhou
- Northwestern University Feinberg School of Medicine, Department of Neurology, Chicago, Illinois, United States of America
- * E-mail:
| | - Torben Noto
- Northwestern University Feinberg School of Medicine, Department of Neurology, Chicago, Illinois, United States of America
| | - Qiaohan Yang
- Northwestern University Feinberg School of Medicine, Department of Neurology, Chicago, Illinois, United States of America
| | - Stephan U. Schuele
- Northwestern University Feinberg School of Medicine, Department of Neurology, Chicago, Illinois, United States of America
| | - Josef Parvizi
- Laboratory of Behavioral and Cognitive Neuroscience, Department of Neurology and Neurological Sciences, Stanford University Palo Alto, Stanford, California, United States of America
| | - Jay A. Gottfried
- University of Pennsylvania, Perelman School of Medicine, Department of Neurology, Philadelphia, Pennsylvania, United States of America
- University of Pennsylvania, School of Arts and Sciences, Department of Psychology, Philadelphia, Pennsylvania, United States of America
| | - Shasha Wu
- University of Chicago, Department of Neurology, Chicago, Illinois, United States of America
| | - Joshua M. Rosenow
- Northwestern University Feinberg School of Medicine, Department of Neurosurgery, Illinois, United States of America
| | - Mohamad Z. Koubeissi
- George Washington University, Department of Neurology, Washington DC, United States of America
| | - Gregory Lane
- Northwestern University Feinberg School of Medicine, Department of Neurology, Chicago, Illinois, United States of America
| | - Christina Zelano
- Northwestern University Feinberg School of Medicine, Department of Neurology, Chicago, Illinois, United States of America
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15
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Wilson DA, Fleming G, Vervoordt SM, Coureaud G. Cortical processing of configurally perceived odor mixtures. Brain Res 2020; 1729:146617. [PMID: 31866364 PMCID: PMC6941848 DOI: 10.1016/j.brainres.2019.146617] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 12/12/2019] [Accepted: 12/17/2019] [Indexed: 02/01/2023]
Abstract
Most odors are not composed of a single volatile chemical species, but rather are mixtures of many different volatile molecules, the perception of which is dependent on the identity and relative concentrations of the components. Changing either the identity or ratio of components can lead to shifts between configural and elemental perception of the mixture. For example, a 30/70 ratio of ethyl isobutyrate (odorant A, a strawberry scent) and ethyl maltol (odorant B, a caramel scent) is perceived as pineapple by humans - a configural percept distinct from the components. In contrast, a 68/32 ratio of the same odorants is perceived elementally, and is identified as the component odors. Here, we examined single-unit responses in the anterior and posterior piriform cortex (aPCX and pPCX) of mice to these A and B mixtures. We first demonstrate that mouse behavior is consistent with a configural/elemental perceptual shift as concentration ratio varies. We then compared responses to the configural mixture to those evoked by the elemental mixture, as well as to the individual components. Hierarchical cluster analyses suggest that in the mouse aPCX, the configural mixture was coded as distinct from both components, while the elemental mixture was coded as similar to the components. In contrast, mixture perception did not predict pPCX ensemble coding. Similar electrophysiological results were also observed in rats. The results suggest similar perceptual characteristics of the AB mixture across species, and a division in the roles of aPCX and pPCX in the coding of configural and elemental odor mixtures.
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Affiliation(s)
- Donald A Wilson
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA; Child & Adolescent Psychiatry, NYU School of Medicine, New York, NY, USA.
| | - Gloria Fleming
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Samantha M Vervoordt
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Gérard Coureaud
- Lyon Neuroscience Research Center, INSERM U1028/CNRS UMR 5292/Lyon 1 University, Bron, France.
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16
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Strauch C, Manahan-Vaughan D. Orchestration of Hippocampal Information Encoding by the Piriform Cortex. Cereb Cortex 2020; 30:135-147. [PMID: 31220213 PMCID: PMC7029697 DOI: 10.1093/cercor/bhz077] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 03/08/2019] [Accepted: 03/18/2019] [Indexed: 01/03/2023] Open
Abstract
The hippocampus utilizes olfactospatial information to encode sensory experience by means of synaptic plasticity. Odor exposure is also a potent impetus for hippocampus-dependent memory retrieval. Here, we explored to what extent the piriform cortex directly impacts upon hippocampal information processing and storage. In behaving rats, test-pulse stimulation of the anterior piriform cortex (aPC) evoked field potentials in the dentate gyrus (DG). Patterned stimulation of the aPC triggered both long-term potentiation (LTP > 24 h) and short-term depression (STD), in a frequency-dependent manner. Dual stimulation of the aPC and perforant path demonstrated subordination of the aPC response, which was nonetheless completely distinct in profile to perforant path-induced DG plasticity. Correspondingly, patterned aPC stimulation resulted in somatic immediate early gene expression in the DG that did not overlap with responses elicited by perforant path stimulation. Our results support that the piriform cortex engages in specific control of hippocampal information processing and encoding. This process may underlie the unique role of olfactory cues in information encoding and retrieval of hippocampus-dependent associative memories.
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Affiliation(s)
- Christina Strauch
- Department of Neurophysiology, Medical Faculty
- International Graduate School for Neuroscience, Ruhr University Bochum, Universitaetsstr. Bochum, Germany
| | - Denise Manahan-Vaughan
- Department of Neurophysiology, Medical Faculty
- International Graduate School for Neuroscience, Ruhr University Bochum, Universitaetsstr. Bochum, Germany
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17
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Weiss T, Soroka T, Gorodisky L, Shushan S, Snitz K, Weissgross R, Furman-Haran E, Dhollander T, Sobel N. Human Olfaction without Apparent Olfactory Bulbs. Neuron 2020; 105:35-45.e5. [PMID: 31706696 PMCID: PMC6953431 DOI: 10.1016/j.neuron.2019.10.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 07/16/2019] [Accepted: 10/01/2019] [Indexed: 12/12/2022]
Abstract
The olfactory bulbs (OBs) are the first site of odor representation in the mammalian brain, and their unique ultrastructure is considered a necessary substrate for spatiotemporal coding of smell. Given this, we were struck by the serendipitous observation at MRI of two otherwise healthy young left-handed women, yet with no apparent OBs. Standardized tests revealed normal odor awareness, detection, discrimination, identification, and representation. Functional MRI of these women's brains revealed that odorant-induced activity in piriform cortex, the primary OB target, was similar in its extent to that of intact controls. Finally, review of a public brain-MRI database with 1,113 participants (606 women) also tested for olfactory performance, uncovered olfaction without anatomically defined OBs in ∼0.6% of women and ∼4.25% of left-handed women. Thus, humans can perform the basic facets of olfaction without canonical OBs, implying extreme plasticity in the functional neuroanatomy of this sensory system.
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Affiliation(s)
- Tali Weiss
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, Rehovot, Israel; Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
| | - Timna Soroka
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, Rehovot, Israel; Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | - Lior Gorodisky
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, Rehovot, Israel; Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | - Sagit Shushan
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, Rehovot, Israel; Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | - Kobi Snitz
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, Rehovot, Israel; Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | - Reut Weissgross
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, Rehovot, Israel; Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | - Edna Furman-Haran
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, Rehovot, Israel
| | - Thijs Dhollander
- The Florey Institute of Neuroscience and Mental Health, Melbourne, VIC, Australia; The Florey Department of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia
| | - Noam Sobel
- The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, Rehovot, Israel; Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
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18
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Perrier SP, Gleizes M, Fonta C, Nowak LG. Effect of adenosine on short-term synaptic plasticity in mouse piriform cortex in vitro: adenosine acts as a high-pass filter. Physiol Rep 2019; 7:e13992. [PMID: 30740934 PMCID: PMC6369103 DOI: 10.14814/phy2.13992] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 01/02/2019] [Indexed: 02/01/2023] Open
Abstract
We examined the effect of adenosine and of adenosine A1 receptor blockage on short-term synaptic plasticity in slices of adult mouse anterior piriform cortex maintained in vitro in an in vivo-like ACSF. Extracellular recording of postsynaptic responses was performed in layer 1a while repeated electrical stimulation (5-pulse-trains, frequency between 3.125 and 100 Hz) was applied to the lateral olfactory tract. Our stimulation protocol was aimed at covering the frequency range of oscillatory activities observed in the olfactory bulb in vivo. In control condition, postsynaptic response amplitude showed a large enhancement for stimulation frequencies in the beta and gamma frequency range. A phenomenological model of short-term synaptic plasticity fitted to the data suggests that this frequency-dependent enhancement can be explained by the interplay between a short-term facilitation mechanism and two short-term depression mechanisms, with fast and slow recovery time constants. In the presence of adenosine, response amplitude evoked by low-frequency stimulation decreased in a dose-dependent manner (IC50 = 70 μmol/L). Yet short-term plasticity became more dominated by facilitation and less influenced by depression. Both changes compensated for the initial decrease in response amplitude in a way that depended on stimulation frequency: compensation was strongest at high frequency, up to restoring response amplitudes to values similar to those measured in control condition. The model suggested that the main effects of adenosine were to decrease neurotransmitter release probability and to attenuate short-term depression mechanisms. Overall, these results suggest that adenosine does not merely inhibit neuronal activity but acts in a more subtle, frequency-dependent manner.
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19
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Chandra N, Awasthi R, Ozdogan T, Johenning FW, Imbrosci B, Morris G, Schmitz D, Barkai E. A Cellular Mechanism Underlying Enhanced Capability for Complex Olfactory Discrimination Learning. eNeuro 2019; 6:ENEURO.0198-18.2019. [PMID: 30783614 PMCID: PMC6378325 DOI: 10.1523/eneuro.0198-18.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 12/26/2018] [Accepted: 01/06/2019] [Indexed: 11/21/2022] Open
Abstract
The biological mechanisms underlying complex forms of learning requiring the understanding of rules based on previous experience are not yet known. Previous studies have raised the intriguing possibility that improvement in complex learning tasks requires the long-term modulation of intrinsic neuronal excitability, induced by reducing the conductance of the slow calcium-dependent potassium current (sIAHP) simultaneously in most neurons in the relevant neuronal networks in several key brain areas. Such sIAHP reduction is expressed in attenuation of the postburst afterhyperpolarization (AHP) potential, and thus in enhanced repetitive action potential firing. Using complex olfactory discrimination (OD) learning as a model for complex learning, we show that brief activation of the GluK2 subtype glutamate receptor results in long-lasting enhancement of neuronal excitability in neurons from controls, but not from trained rats. Such an effect can be obtained by a brief tetanic synaptic stimulation or by direct application of kainate, both of which reduce the postburst AHP in pyramidal neurons. Induction of long-lasting enhancement of neuronal excitability is mediated via a metabotropic process that requires PKC and ERK activation. Intrinsic neuronal excitability cannot be modulated by synaptic activation in neurons from GluK2 knock-out mice. Accordingly, these mice are incapable of learning the complex OD task. Moreover, viral-induced overexpression of Gluk2 in piriform cortex pyramidal neurons results in remarkable enhancement of complex OD learning. Thus, signaling via kainate receptors has a central functional role in higher cognitive abilities.
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Affiliation(s)
| | | | | | | | | | | | | | - Edi Barkai
- University of Haifa, Haifa 3498838, Israel
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20
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Schaffer ES, Stettler DD, Kato D, Choi GB, Axel R, Abbott LF. Odor Perception on the Two Sides of the Brain: Consistency Despite Randomness. Neuron 2018; 98:736-742.e3. [PMID: 29706585 PMCID: PMC6026547 DOI: 10.1016/j.neuron.2018.04.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 02/03/2018] [Accepted: 04/03/2018] [Indexed: 11/22/2022]
Abstract
Neurons in piriform cortex receive input from a random collection of glomeruli, resulting in odor representations that lack the stereotypic organization of the olfactory bulb. We have performed in vivo optical imaging and mathematical modeling to demonstrate that correlations are retained in the transformation from bulb to piriform cortex, a feature essential for generalization across odors. Random connectivity also implies that the piriform representation of a given odor will differ among different individuals and across brain hemispheres in a single individual. We show that these different representations can nevertheless support consistent agreement about odor quality across a range of odors. Our model also demonstrates that, whereas odor discrimination and categorization require far fewer neurons than reside in piriform cortex, consistent generalization may require the full complement of piriform neurons.
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Affiliation(s)
- Evan S Schaffer
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA.
| | - Dan D Stettler
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA
| | - Daniel Kato
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA
| | - Gloria B Choi
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA
| | - Richard Axel
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA; Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA; Howard Hughes Medical Institute, Columbia University, New York, NY 10032, USA
| | - L F Abbott
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA; Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA
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21
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Tsuji C, Tsuji T, Allchorne A, Leng G, Ludwig M. Effects of lateral olfactory tract stimulation on Fos immunoreactivity in vasopressin neurones of the rat piriform cortex. J Neuroendocrinol 2017; 29:e12531. [PMID: 28862781 DOI: 10.1111/jne.12531] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 08/22/2017] [Accepted: 08/28/2017] [Indexed: 11/28/2022]
Abstract
In the main olfactory system, odours are registered at the main olfactory epithelium and are then processed at the main olfactory bulb (MOB) and, subsequently, by the anterior olfactory nucleus (AON), the piriform cortex (PC) and the cortical amygdala. Previously, we reported populations of vasopressin neurones in different areas of the rat olfactory system, including the MOB, accessory olfactory bulb (AOB) and the AON and showed that these are involved in the coding of social odour information. Utilising immunohistochemistry and a transgenic rat in which an enhanced green fluorescent protein reporter gene is expressed in vasopressin neurones (eGFP-vasopressin), we now show a population of vasopressin neurones in the PC. The vasopressin neurones are predominantly located in the layer II of the PC and the majority co-express the excitatory transmitter glutamate. Furthermore, there is no sex difference in the number of neurones expressing vasopressin. Electrical stimulation of the lateral olfactory tract leads to a significant increase in the number of Fos-positive nuclei in the PC, MOB, AOB, dorsal AON and supraoptic nucleus (SON). However, there was only a significant increase in Fos expression in vasopressin cells of the PC and SON. Thus, functionally distinct populations of vasopressin cells are implicated in olfactory processing at multiple stages of the olfactory pathway.
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Affiliation(s)
- C Tsuji
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
| | - T Tsuji
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
| | - A Allchorne
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
| | - G Leng
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
| | - M Ludwig
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
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22
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Gleizes M, Perrier SP, Fonta C, Nowak LG. Prominent facilitation at beta and gamma frequency range revealed with physiological calcium concentration in adult mouse piriform cortex in vitro. PLoS One 2017; 12:e0183246. [PMID: 28820903 PMCID: PMC5562311 DOI: 10.1371/journal.pone.0183246] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 08/01/2017] [Indexed: 12/25/2022] Open
Abstract
Neuronal activity is characterized by a diversity of oscillatory phenomena that are associated with multiple behavioral and cognitive processes, yet the functional consequences of these oscillations are not fully understood. Our aim was to determine whether and how these different oscillatory activities affect short-term synaptic plasticity (STP), using the olfactory system as a model. In response to odorant stimuli, the olfactory bulb displays a slow breathing rhythm as well as beta and gamma oscillations. Since the firing of olfactory bulb projecting neurons is phase-locked with beta and gamma oscillations, structures downstream from the olfactory bulb should be driven preferentially at these frequencies. We examined STP exhibited by olfactory bulb inputs in slices of adult mouse piriform cortex maintained in vitro in an in vivo-like ACSF (calcium concentration: 1.1 mM). We replaced the presynaptic neuronal firing rate by repeated electrical stimulation (frequency between 3.125 and 100 Hz) applied to the lateral olfactory tract. Our results revealed a considerable enhancement of postsynaptic response amplitude for stimulation frequencies in the beta and gamma range. A phenomenological model of STP fitted to the data suggests that the experimental results can be explained by the interplay between three mechanisms: a short-term facilitation mechanism (time constant ≈160 msec), and two short-term depression mechanisms (recovery time constants <20 msec and ≈140 msec). Increasing calcium concentration (2.2 mM) resulted in an increase in the time constant of facilitation and in a strengthening of the slowest depression mechanism. As a result, response enhancement was reduced and its peak shifted toward the low beta and alpha ranges while depression became predominant in the gamma band. Using environmental conditions corresponding to those that prevail in vivo, our study shows that STP in the lateral olfactory tract to layer Ia synapse allows amplification of olfactory bulb inputs at beta and gamma frequencies.
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Affiliation(s)
- Marie Gleizes
- Centre de Recherche Cerveau et Cognition, Université de Toulouse, Toulouse, France
- Unité Mixte de Recherche 5549, Centre National de la Recherche Scientifique, Toulouse, France
| | - Simon P. Perrier
- Centre de Recherche Cerveau et Cognition, Université de Toulouse, Toulouse, France
- Unité Mixte de Recherche 5549, Centre National de la Recherche Scientifique, Toulouse, France
| | - Caroline Fonta
- Centre de Recherche Cerveau et Cognition, Université de Toulouse, Toulouse, France
- Unité Mixte de Recherche 5549, Centre National de la Recherche Scientifique, Toulouse, France
| | - Lionel G. Nowak
- Centre de Recherche Cerveau et Cognition, Université de Toulouse, Toulouse, France
- Unité Mixte de Recherche 5549, Centre National de la Recherche Scientifique, Toulouse, France
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Roland B, Deneux T, Franks KM, Bathellier B, Fleischmann A. Odor identity coding by distributed ensembles of neurons in the mouse olfactory cortex. eLife 2017; 6:e26337. [PMID: 28489003 PMCID: PMC5438249 DOI: 10.7554/elife.26337] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 04/29/2017] [Indexed: 11/18/2022] Open
Abstract
Olfactory perception and behaviors critically depend on the ability to identify an odor across a wide range of concentrations. Here, we use calcium imaging to determine how odor identity is encoded in olfactory cortex. We find that, despite considerable trial-to-trial variability, odor identity can accurately be decoded from ensembles of co-active neurons that are distributed across piriform cortex without any apparent spatial organization. However, piriform response patterns change substantially over a 100-fold change in odor concentration, apparently degrading the population representation of odor identity. We show that this problem can be resolved by decoding odor identity from a subpopulation of concentration-invariant piriform neurons. These concentration-invariant neurons are overrepresented in piriform cortex but not in olfactory bulb mitral and tufted cells. We therefore propose that distinct perceptual features of odors are encoded in independent subnetworks of neurons in the olfactory cortex.
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Affiliation(s)
- Benjamin Roland
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241, INSERM U1050, Paris, France
| | - Thomas Deneux
- Unité de Neuroscience, Information et Complexité, Centre National de la Recherche Scientifique, UPR 3293, Gif-sur-Yvette, France
| | - Kevin M Franks
- Department of Neurobiology, Duke University, Durham, United States
| | - Brice Bathellier
- Unité de Neuroscience, Information et Complexité, Centre National de la Recherche Scientifique, UPR 3293, Gif-sur-Yvette, France
| | - Alexander Fleischmann
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241, INSERM U1050, Paris, France
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Choy JM, Suzuki N, Shima Y, Budisantoso T, Nelson SB, Bekkers JM. Optogenetic Mapping of Intracortical Circuits Originating from Semilunar Cells in the Piriform Cortex. Cereb Cortex 2017; 27:589-601. [PMID: 26503263 PMCID: PMC5939214 DOI: 10.1093/cercor/bhv258] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Despite its comparatively simple trilaminar architecture, the primary olfactory (piriform) cortex of mammals is capable of performing sophisticated sensory processing, an ability that is thought to depend critically on its extensive associational (intracortical) excitatory circuits. Here, we used a novel transgenic mouse model and optogenetics to measure the connectivity of associational circuits that originate in semilunar (SL) cells in layer 2a of the anterior piriform cortex (aPC). We generated a mouse line (48L) in which channelrhodopsin-2 (ChR) could be selectively expressed in a subset of SL cells. Light-evoked excitatory postsynaptic currents (EPSCs) could be evoked in superficial pyramidal cells (17.4% of n = 86 neurons) and deep pyramidal cells (33.3%, n = 9) in the aPC, but never in ChR- SL cells (0%, n = 34). Thus, SL cells monosynaptically excite pyramidal cells, but not other SL cells. Light-evoked EPSCs were also selectively elicited in 3 classes of GABAergic interneurons in layer 3 of the aPC. Our results show that SL cells are specialized for providing feedforward excitation of specific classes of neurons in the aPC, confirming that SL cells comprise a functionally distinctive input layer.
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Affiliation(s)
- Julian M.C. Choy
- Eccles Institute of Neuroscience, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia
| | - Norimitsu Suzuki
- Eccles Institute of Neuroscience, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia
| | - Yasuyuki Shima
- Department of Biology and National Center for Behavioral Genomics, Brandeis University, Waltham, MA 02453, USA
| | - Timotheus Budisantoso
- Eccles Institute of Neuroscience, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia
- Department of Physiological Sciences, Graduate University for Advanced Studies, Okazaki444-8787, Japan
- Current address: Department of Physiology, School of Medicine, Keio University, Shinjuku, Tokyo 160-8582, Japan
| | - Sacha B. Nelson
- Department of Biology and National Center for Behavioral Genomics, Brandeis University, Waltham, MA 02453, USA
| | - John M. Bekkers
- Eccles Institute of Neuroscience, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia
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25
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Maier JX, Blankenship ML, Li JX, Katz DB. A Multisensory Network for Olfactory Processing. Curr Biol 2015; 25:2642-50. [PMID: 26441351 DOI: 10.1016/j.cub.2015.08.060] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 08/26/2015] [Accepted: 08/27/2015] [Indexed: 11/18/2022]
Abstract
Primary gustatory cortex (GC) is connected (both mono- and polysynaptically) to primary olfactory (piriform) cortex (PC)-connections that might be hypothesized to underlie the construction of a "flavor" percept when both gustatory and olfactory stimuli are present. Here we use multisite electrophysiology and optical inhibition of GC neurons (GCx, produced via infection with ArchT) to demonstrate that, indeed, during gustatory stimulation, taste-selective information is transmitted from GC to PC. We go on to show that these connections impact olfactory processing even in the absence of gustatory stimulation: GCx alters PC responses to olfactory stimuli presented alone, enhancing some and eliminating others, despite leaving the path from nasal epithelium to PC intact. Finally, we show the functional importance of this latter phenomenon, demonstrating that GCx renders rats unable to properly recognize odor stimuli. This sequence of findings suggests that sensory processing may be more intrinsically integrative than previously thought.
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Affiliation(s)
- Joost X Maier
- Department of Psychology, Brandeis University, Waltham, MA 02453, USA; Volen National Center for Complex Systems, Brandeis University, Waltham, MA 02453, USA; Department of Neurobiology and Anatomy, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA.
| | | | - Jennifer X Li
- Department of Psychology, Brandeis University, Waltham, MA 02453, USA
| | - Donald B Katz
- Department of Psychology, Brandeis University, Waltham, MA 02453, USA; Volen National Center for Complex Systems, Brandeis University, Waltham, MA 02453, USA; Program in Neuroscience, Brandeis University, Waltham, MA 02453, USA
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26
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Cohen Y, Wilson DA, Barkai E. Differential modifications of synaptic weights during odor rule learning: dynamics of interaction between the piriform cortex with lower and higher brain areas. Cereb Cortex 2015; 25:180-91. [PMID: 23960200 PMCID: PMC4415065 DOI: 10.1093/cercor/bht215] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Learning of a complex olfactory discrimination (OD) task results in acquisition of rule learning after prolonged training. Previously, we demonstrated enhanced synaptic connectivity between the piriform cortex (PC) and its ascending and descending inputs from the olfactory bulb (OB) and orbitofrontal cortex (OFC) following OD rule learning. Here, using recordings of evoked field postsynaptic potentials in behaving animals, we examined the dynamics by which these synaptic pathways are modified during rule acquisition. We show profound differences in synaptic connectivity modulation between the 2 input sources. During rule acquisition, the ascending synaptic connectivity from the OB to the anterior and posterior PC is simultaneously enhanced. Furthermore, post-training stimulation of the OB enhanced learning rate dramatically. In sharp contrast, the synaptic input in the descending pathway from the OFC was significantly reduced until training completion. Once rule learning was established, the strength of synaptic connectivity in the 2 pathways resumed its pretraining values. We suggest that acquisition of olfactory rule learning requires a transient enhancement of ascending inputs to the PC, synchronized with a parallel decrease in the descending inputs. This combined short-lived modulation enables the PC network to reorganize in a manner that enables it to first acquire and then maintain the rule.
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Affiliation(s)
- Yaniv Cohen
- Departments of Biology
- Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Haifa31905, Israel,
- Department of Child and Adolescent Psychiatry, New York University Langone School of Medicine, New York, NY 10016, USA and
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Donald A. Wilson
- Department of Child and Adolescent Psychiatry, New York University Langone School of Medicine, New York, NY 10016, USA and
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Edi Barkai
- Departments of Biology
- Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Haifa31905, Israel,
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27
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Sheridan DC, Hughes AR, Erdélyi F, Szabó G, Hentges ST, Schoppa NE. Matching of feedback inhibition with excitation ensures fidelity of information flow in the anterior piriform cortex. Neuroscience 2014; 275:519-30. [PMID: 24969131 DOI: 10.1016/j.neuroscience.2014.06.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 05/24/2014] [Accepted: 06/12/2014] [Indexed: 11/18/2022]
Abstract
Odor-evoked responses in mitral cells of the olfactory bulb are characterized by prolonged patterns of action potential (spike) activity. If downstream neurons are to respond to each spike in these patterns, the duration of the excitatory response to one spike should be limited, enabling cells to respond to subsequent spikes. To test for such mechanisms, we performed patch-clamp recordings in slices of the mouse anterior piriform cortex. Mitral cell axons in the lateral olfactory tract (LOT) were stimulated electrically at different intensities and with various frequency patterns to mimic changing input conditions that the piriform cortex likely encounters in vivo. We found with cell-attached measurements that superficial pyramidal (SP) cells in layer 2 consistently responded to LOT stimulation across conditions with a limited number (1-2) of spikes per stimulus pulse. The key synaptic feature accounting for the limited spike number appeared to be somatic inhibition derived from layer 3 fast-spiking cells. This inhibition tracked the timing of the first spike in SP cells across conditions, which naturally limited the spike number to 1-2. These response features to LOT stimulation were, moreover, not unique to SP cells, also occurring in a population of fluorescently labeled interneurons in glutamic acid decarboxylase 65-eGFP mice. That these different cortical cells respond to incoming inputs with 1-2 spikes per stimulus may be especially critical for relaying bulbar information contained in synchronized oscillations at beta (15-30Hz) or gamma (30-80Hz) frequencies.
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Affiliation(s)
- D C Sheridan
- University of Colorado Anschutz Medical Campus, Department of Physiology & Biophysics, 12800 East 19th Avenue, Aurora, CO 80045, United States.
| | - A R Hughes
- Department of Biomedical Sciences, Colorado State University, 1680 Campus Delivery, Fort Collins, CO 80523, United States
| | - F Erdélyi
- Institute of Experimental Medicine, Division of Medical Gene Technology, Budapest, Hungary
| | - G Szabó
- Institute of Experimental Medicine, Division of Medical Gene Technology, Budapest, Hungary.
| | - S T Hentges
- Department of Biomedical Sciences, Colorado State University, 1680 Campus Delivery, Fort Collins, CO 80523, United States.
| | - N E Schoppa
- University of Colorado Anschutz Medical Campus, Department of Physiology & Biophysics, 12800 East 19th Avenue, Aurora, CO 80045, United States.
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