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Średniawa W, Borzymowska Z, Kondrakiewicz K, Jurgielewicz P, Mindur B, Hottowy P, Wójcik DK, Kublik E. Local contribution to the somatosensory evoked potentials in rat's thalamus. PLoS One 2024; 19:e0301713. [PMID: 38593141 PMCID: PMC11003638 DOI: 10.1371/journal.pone.0301713] [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: 11/24/2023] [Accepted: 03/19/2024] [Indexed: 04/11/2024] Open
Abstract
Local Field Potential (LFP), despite its name, often reflects remote activity. Depending on the orientation and synchrony of their sources, both oscillations and more complex waves may passively spread in brain tissue over long distances and be falsely interpreted as local activity at such distant recording sites. Here we show that the whisker-evoked potentials in the thalamic nuclei are of local origin up to around 6 ms post stimulus, but the later (7-15 ms) wave is overshadowed by a negative component reaching from cortex. This component can be analytically removed and local thalamic LFP can be recovered reliably using Current Source Density analysis. We used model-based kernel CSD (kCSD) method which allowed us to study the contribution of local and distant currents to LFP from rat thalamic nuclei and barrel cortex recorded with multiple, non-linear and non-regular multichannel probes. Importantly, we verified that concurrent recordings from the cortex are not essential for reliable thalamic CSD estimation. The proposed framework can be used to analyze LFP from other brain areas and has consequences for general LFP interpretation and analysis.
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Affiliation(s)
- Władysław Średniawa
- Laboratory of Neuroinformatics, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Warsaw, Poland
| | - Zuzanna Borzymowska
- Neurobiology of Emotions Laboratory, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Warsaw, Poland
| | - Kacper Kondrakiewicz
- Neurobiology of Emotions Laboratory, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Warsaw, Poland
| | - Paweł Jurgielewicz
- AGH University of Science and Technology in Kraków, Faculty of Physics and Applied Computer Science, Krakow, Poland
| | - Bartosz Mindur
- AGH University of Science and Technology in Kraków, Faculty of Physics and Applied Computer Science, Krakow, Poland
| | - Paweł Hottowy
- AGH University of Science and Technology in Kraków, Faculty of Physics and Applied Computer Science, Krakow, Poland
| | - Daniel K. Wójcik
- Laboratory of Neuroinformatics, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Warsaw, Poland
- Jagiellonian University, Faculty of Management and Social Communication, Jagiellonian University, Krakow, Poland
| | - Ewa Kublik
- Neurobiology of Emotions Laboratory, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Warsaw, Poland
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Ernault AC, Al-Shama RFM, Li J, Devalla HD, de Groot JR, Coronel R, Vigmond E, Boukens BJ. Interpretation of field and LEAP potentials recorded from cardiomyocyte monolayers. Am J Physiol Heart Circ Physiol 2024; 326:H800-H811. [PMID: 38180452 DOI: 10.1152/ajpheart.00463.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 12/04/2023] [Accepted: 01/02/2024] [Indexed: 01/06/2024]
Abstract
Multielectrode arrays (MEAs) are the method of choice for electrophysiological characterization of cardiomyocyte monolayers. The field potentials recorded using an MEA are like extracellular electrograms recorded from the myocardium using conventional electrodes. Nevertheless, different criteria are used to interpret field potentials and extracellular electrograms, which hamper correct interpretation and translation to the patient. To validate the criteria for interpretation of field potentials, we used neonatal rat cardiomyocytes to generate monolayers. We recorded field potentials using an MEA and simultaneously recorded action potentials using sharp microelectrodes. In parallel, we recreated our experimental setting in silico and performed simulations. We show that the amplitude of the local RS complex of a field potential correlated with conduction velocity in silico but not in vitro. The peak time of the T wave in field potentials exhibited a strong correlation with APD90 while the steepest upslope correlated well with APD50. However, this relationship only holds when the T wave displayed a biphasic pattern. Next, we simulated local extracellular action potentials (LEAPs). The shape of the LEAP differed markedly from the shape of the local action potential, but the final duration of the LEAP coincided with APD90. Criteria for interpretation of extracellular electrograms should be applied to field potentials. This will provide a strong basis for the analysis of heterogeneity in conduction velocity and repolarization in cultured monolayers of cardiomyocytes. Finally, a LEAP is not a recording of the local action potential but is generated by intracellular current provided by neighboring cardiomyocytes and is superior to field potential duration in estimating APD90.NEW & NOTEWORTHY We present a physiological basis for the interpretation of multielectrode array-derived, extracellular, electrical signals.
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Affiliation(s)
- Auriane C Ernault
- Heart Center, Department of Clinical and Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - Rushd F M Al-Shama
- Heart Center, Department of Clinical and Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - Jiuru Li
- Department of Medical Biology, Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - Harsha D Devalla
- Department of Medical Biology, Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - Joris R de Groot
- Heart Center, Department of Clinical and Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - Ruben Coronel
- Heart Center, Department of Clinical and Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - Edward Vigmond
- IHU Liryc, Fondation Bordeaux Université, Bordeaux, France
- University of Bordeaux, Talence, France
| | - Bastiaan J Boukens
- Department of Medical Biology, Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, Amsterdam, The Netherlands
- Department of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, The Netherlands
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Kennedy JP, Zhou Y, Qin Y, Lovett SD, Cooper T, Sheremet A, Burke SN, Maurer AP. Visual cortical LFP in relation to the hippocampal theta rhythm in track running rats. Front Cell Neurosci 2023; 17:1144260. [PMID: 37408856 PMCID: PMC10318345 DOI: 10.3389/fncel.2023.1144260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Accepted: 06/01/2023] [Indexed: 07/07/2023] Open
Abstract
Theta oscillations in the primary visual cortex (VC) have been observed during running tasks, but the mechanism behind their generation is not well understood. Some studies have suggested that theta in the VC is locally generated, while others have proposed that it is volume conducted from the hippocampus. The present study aimed to investigate the relationship between hippocampal and VC LFP dynamics. Analysis of power spectral density revealed that LFP in the VC was similar to that in the hippocampus, but with lower overall magnitude. As running velocity increased, both the power and frequency of theta and its harmonics increased in the VC, similarly to what is observed in the hippocampus. Current source density analysis triggered to theta did not identify distinct current sources and sinks in the VC, supporting the idea that theta in the VC is conducted from the adjacent hippocampus. Phase coupling between theta, its harmonics, and gamma is a notable feature in the hippocampus, particularly in the lacunosum moleculare. While some evidence of coupling between theta and its harmonics in the VC was found, bicoherence estimates did not reveal significant phase coupling between theta and gamma. Similar results were seen in the cross-region bicoherence analysis, where theta showed strong coupling with its harmonics with increasing velocity. Thus, theta oscillations observed in the VC during running tasks are likely due to volume conduction from the hippocampus.
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Affiliation(s)
- Jack P. Kennedy
- Department of Neuroscience, College of Medicine, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Yuchen Zhou
- Department of Psychiatry, School of Medicine, Yale University, New Haven, CT, United States
| | - Yu Qin
- Department of Neuroscience, College of Medicine, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
- Engineering School of Sustainable Infrastructure and Environment, Herbert Wertheim College of Engineering, University of Florida, Gainesville, FL, United States
| | - Sarah D. Lovett
- Department of Neuroscience, College of Medicine, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Tara Cooper
- Department of Neuroscience, College of Medicine, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Alex Sheremet
- Department of Neuroscience, College of Medicine, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
- Engineering School of Sustainable Infrastructure and Environment, Herbert Wertheim College of Engineering, University of Florida, Gainesville, FL, United States
| | - Sara N. Burke
- Department of Neuroscience, College of Medicine, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Andrew P. Maurer
- Department of Neuroscience, College of Medicine, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
- Engineering School of Sustainable Infrastructure and Environment, Herbert Wertheim College of Engineering, University of Florida, Gainesville, FL, United States
- Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States
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Tovar DA, Westerberg JA, Cox MA, Dougherty K, Wallace MT, Bastos AM, Maier A. Near-field potentials index local neural computations more accurately than population spiking. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.11.540026. [PMID: 37214905 PMCID: PMC10197629 DOI: 10.1101/2023.05.11.540026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Local field potentials (LFP) are low-frequency extracellular voltage fluctuations thought to primarily arise from synaptic activity. However, unlike highly localized neuronal spiking, LFP is spatially less specific. LFP measured at one location is not entirely generated there due to far-field contributions that are passively conducted across volumes of neural tissue. We sought to quantify how much information within the locally generated, near-field low-frequency activity (nfLFP) is masked by volume-conducted far-field signals. To do so, we measured laminar neural activity in primary visual cortex (V1) of monkeys viewing sequences of multifeatured stimuli. We compared information content of regular LFP and nfLFP that was mathematically stripped of volume-conducted far-field contributions. Information content was estimated by decoding stimulus properties from neural responses via spatiotemporal multivariate pattern analysis. Volume-conducted information differed from locally generated information in two important ways: (1) for stimulus features relevant to V1 processing (orientation and eye-of-origin), nfLFP contained more information. (2) in contrast, the volume-conducted signal was more informative regarding temporal context (relative stimulus position in a sequence), a signal likely to be coming from elsewhere. Moreover, LFP and nfLFP differed both spectrally as well as spatially, urging caution regarding the interpretations of individual frequency bands and/or laminar patterns of LFP. Most importantly, we found that population spiking of local neurons was less informative than either the LFP or nfLFP, with nfLFP containing most of the relevant information regarding local stimulus processing. These findings suggest that the optimal way to read out local computational processing from neural activity is to decode the local contributions to LFP, with significant information loss hampering both regular LFP and local spiking. Author’s Contributions Conceptualization, D.A.T., J.A.W, and A.M.; Data Collection, J.A.W., M.A.C., K.D.; Formal Analysis, D.A.T. and J.A.W.; Data Visualization, D.A.T. and J.A.W.; Original Draft, D.A.T., J.A.W., and A.M.; Revisions and Final Draft, D.A.T., J.A.W., M.A.C., K.D., M.T.W., A.M.B., and A.M. Competing Interests The authors declare no conflicts of interest.
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Herreras O, Torres D, Makarov VA, Makarova J. Theoretical considerations and supporting evidence for the primary role of source geometry on field potential amplitude and spatial extent. Front Cell Neurosci 2023; 17:1129097. [PMID: 37066073 PMCID: PMC10097999 DOI: 10.3389/fncel.2023.1129097] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 03/15/2023] [Indexed: 04/03/2023] Open
Abstract
Field potential (FP) recording is an accessible means to capture the shifts in the activity of neuron populations. However, the spatial and composite nature of these signals has largely been ignored, at least until it became technically possible to separate activities from co-activated sources in different structures or those that overlap in a volume. The pathway-specificity of mesoscopic sources has provided an anatomical reference that facilitates transcending from theoretical analysis to the exploration of real brain structures. We review computational and experimental findings that indicate how prioritizing the spatial geometry and density of sources, as opposed to the distance to the recording site, better defines the amplitudes and spatial reach of FPs. The role of geometry is enhanced by considering that zones of the active populations that act as sources or sinks of current may arrange differently with respect to each other, and have different geometry and densities. Thus, observations that seem counterintuitive in the scheme of distance-based logic alone can now be explained. For example, geometric factors explain why some structures produce FPs and others do not, why different FP motifs generated in the same structure extend far while others remain local, why factors like the size of an active population or the strong synchronicity of its neurons may fail to affect FPs, or why the rate of FP decay varies in different directions. These considerations are exemplified in large structures like the cortex and hippocampus, in which the role of geometrical elements and regional activation in shaping well-known FP oscillations generally go unnoticed. Discovering the geometry of the sources in play will decrease the risk of population or pathway misassignments based solely on the FP amplitude or temporal pattern.
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Affiliation(s)
- Oscar Herreras
- Laboratory of Experimental and Computational Neurophysiology, Department of Translational Neuroscience, Cajal Institute, Spanish National Research Council, Madrid, Spain
- *Correspondence: Oscar Herreras,
| | - Daniel Torres
- Laboratory of Experimental and Computational Neurophysiology, Department of Translational Neuroscience, Cajal Institute, Spanish National Research Council, Madrid, Spain
| | - Valeriy A. Makarov
- Institute for Interdisciplinary Mathematics, School of Mathematics, Universidad Complutense de Madrid, Madrid, Spain
| | - Julia Makarova
- Laboratory of Experimental and Computational Neurophysiology, Department of Translational Neuroscience, Cajal Institute, Spanish National Research Council, Madrid, Spain
- Julia Makarova,
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Herreras O, Torres D, Martín-Vázquez G, Hernández-Recio S, López-Madrona VJ, Benito N, Makarov VA, Makarova J. Site-dependent shaping of field potential waveforms. Cereb Cortex 2022; 33:3636-3650. [PMID: 35972425 PMCID: PMC10068269 DOI: 10.1093/cercor/bhac297] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 07/07/2022] [Accepted: 07/08/2022] [Indexed: 11/13/2022] Open
Abstract
The activity of neuron populations gives rise to field potentials (FPs) that extend beyond the sources. Their mixing in the volume dilutes the original temporal motifs in a site-dependent manner, a fact that has received little attention. And yet, it potentially rids of physiological significance the time-frequency parameters of individual waves (amplitude, phase, duration). This is most likely to happen when a single source or a local origin is erroneously assumed. Recent studies using spatial treatment of these signals and anatomically realistic modeling of neuron aggregates provide convincing evidence for the multisource origin and site-dependent blend of FPs. Thus, FPs generated in primary structures like the neocortex and hippocampus reach far and cross-contaminate each other but also, they add and even impose their temporal traits on distant regions. Furthermore, both structures house neurons that act as spatially distinct (but overlapped) FP sources whose activation is state, region, and time dependent, making the composition of so-called local FPs highly volatile and strongly site dependent. Since the spatial reach cannot be predicted without source geometry, it is important to assess whether waveforms and temporal motifs arise from a single source; otherwise, those from each of the co-active sources should be sought.
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Affiliation(s)
- Oscar Herreras
- Department of Translational Neuroscience, Cajal Institute, CSIC, Av. Doctor Arce 37, Madrid 28002, Spain
| | - Daniel Torres
- Department of Translational Neuroscience, Cajal Institute, CSIC, Av. Doctor Arce 37, Madrid 28002, Spain
| | - Gonzalo Martín-Vázquez
- Department of Translational Neuroscience, Cajal Institute, CSIC, Av. Doctor Arce 37, Madrid 28002, Spain
| | - Sara Hernández-Recio
- Department of Translational Neuroscience, Cajal Institute, CSIC, Av. Doctor Arce 37, Madrid 28002, Spain
| | - Víctor J López-Madrona
- Department of Translational Neuroscience, Cajal Institute, CSIC, Av. Doctor Arce 37, Madrid 28002, Spain
| | - Nuria Benito
- Department of Translational Neuroscience, Cajal Institute, CSIC, Av. Doctor Arce 37, Madrid 28002, Spain
| | - Valeri A Makarov
- Department of Applied Mathematics, Institute for Interdisciplinary Mathematics, Universidad Complutense of Madrid, Av. Paraninfo s/n, Madrid 28040, Spain
| | - Julia Makarova
- Department of Translational Neuroscience, Cajal Institute, CSIC, Av. Doctor Arce 37, Madrid 28002, Spain.,Department of Applied Mathematics, Institute for Interdisciplinary Mathematics, Universidad Complutense of Madrid, Av. Paraninfo s/n, Madrid 28040, Spain
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Sachella TE, Ihidoype MR, Proulx CD, Pafundo DE, Medina JH, Mendez P, Piriz J. A novel role for the lateral habenula in fear learning. Neuropsychopharmacology 2022; 47:1210-1219. [PMID: 35217797 PMCID: PMC9018839 DOI: 10.1038/s41386-022-01294-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 02/06/2022] [Accepted: 02/08/2022] [Indexed: 02/02/2023]
Abstract
Fear is an extreme form of aversion that underlies pathological conditions such as panic or phobias. Fear conditioning (FC) is the best-understood model of fear learning. In FC the context and a cue are independently associated with a threatening unconditioned stimulus (US). The lateral habenula (LHb) is a general encoder of aversion. However, its role in fear learning remains poorly understood. Here we studied in rats the role of the LHb in FC using optogenetics and pharmacological tools. We found that inhibition or activation of the LHb during entire FC training impaired both cued and contextual FC. In contrast, optogenetic inhibition of the LHb restricted to cue and US presentation impaired cued but not contextual FC. In either case, simultaneous activation of contextual and cued components of FC, by the presentation of the cue in the training context, recovered the conditioned fear response. Our results support the notion that the LHb is required for the formation of independent contextual and cued fear memories, a previously uncharacterized function for this structure, that could be critical in fear generalization.
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Affiliation(s)
- Tomas E. Sachella
- grid.423606.50000 0001 1945 2152Instituto de Fisiología y Biofísica “Bernardo Houssay” (IFIBIO-Houssay), Grupo de Neurociencia de Sistemas, Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Marina R. Ihidoype
- grid.423606.50000 0001 1945 2152Instituto de Fisiología y Biofísica “Bernardo Houssay” (IFIBIO-Houssay), Grupo de Neurociencia de Sistemas, Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Christophe D. Proulx
- grid.23856.3a0000 0004 1936 8390CERVO Brain Research Center, Department of Psychiatry and Neurosciences, Université Laval, Quebec City, Quebec Canada
| | - Diego E. Pafundo
- grid.423606.50000 0001 1945 2152Instituto de Fisiología y Biofísica “Bernardo Houssay” (IFIBIO-Houssay), Grupo de Neurociencia de Sistemas, Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Jorge H. Medina
- grid.423606.50000 0001 1945 2152Instituto de Biología Celular y Neurociencia “Prof. E. De Robertis” (IBCN), Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina ,grid.441574.70000000090137393Instituto Tecnológico de Buenos Aires (ITBA), Buenos Aires, Argentina
| | - Pablo Mendez
- grid.419043.b0000 0001 2177 5516Instituto Cajal, CSIC, Madrid, España
| | - Joaquin Piriz
- Instituto de Fisiología y Biofísica "Bernardo Houssay" (IFIBIO-Houssay), Grupo de Neurociencia de Sistemas, Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina. .,Instituto de Fisiología Biología Molecular y Neurociencias (IFIBYNE), Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.
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Cocina F, Vitalis A, Caflisch A. Unsupervised Methods for Detection of Neural States: Case Study of Hippocampal-Amygdala Interactions. eNeuro 2021; 8:ENEURO.0484-20.2021. [PMID: 34544761 PMCID: PMC8577062 DOI: 10.1523/eneuro.0484-20.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 09/13/2021] [Accepted: 09/14/2021] [Indexed: 11/24/2022] Open
Abstract
The hippocampus and amygdala are functionally coupled brain regions that play a crucial role in processes involving memory and learning. Because interareal communication has been reported both during specific sleep stages and in awake, behaving animals, these brain regions can serve as an archetype to establish that measuring functional interactions is important for comprehending neural systems. To this end, we analyze here a public dataset of local field potentials (LFPs) recorded in rats simultaneously from the hippocampus and amygdala during different behaviors. Employing a specific, time-lagged embedding technique, named topological causality (TC), we infer directed interactions between the LFP band powers of the two regions across six frequency bands in a time-resolved manner. The combined power and interaction signals are processed with our own unsupervised tools developed originally for the analysis of molecular dynamics simulations to effectively visualize and identify putative, neural states that are visited by the animals repeatedly. Our proposed methodology minimizes impositions onto the data, such as isolating specific epochs, or averaging across externally annotated behavioral stages, and succeeds in separating internal states by external labels such as sleep or stimulus events. We show that this works better for two of the three rats we analyzed, and highlight the need to acknowledge individuality in analyses of this type. Importantly, we demonstrate that the quantification of functional interactions is a significant factor in discriminating these external labels, and we suggest our methodology as a general tool for large, multisite recordings.
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Affiliation(s)
- Francesco Cocina
- Biochemistry department, University of Zurich, Zurich, Switzerland CH-8057
| | - Andreas Vitalis
- Biochemistry department, University of Zurich, Zurich, Switzerland CH-8057
| | - Amedeo Caflisch
- Biochemistry department, University of Zurich, Zurich, Switzerland CH-8057
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