51
|
Luongo FJ, Zimmerman CA, Horn ME, Sohal VS. Correlations between prefrontal neurons form a small-world network that optimizes the generation of multineuron sequences of activity. J Neurophysiol 2016; 115:2359-75. [PMID: 26888108 DOI: 10.1152/jn.01043.2015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 02/15/2016] [Indexed: 12/11/2022] Open
Abstract
Sequential patterns of prefrontal activity are believed to mediate important behaviors, e.g., working memory, but it remains unclear exactly how they are generated. In accordance with previous studies of cortical circuits, we found that prefrontal microcircuits in young adult mice spontaneously generate many more stereotyped sequences of activity than expected by chance. However, the key question of whether these sequences depend on a specific functional organization within the cortical microcircuit, or emerge simply as a by-product of random interactions between neurons, remains unanswered. We observed that correlations between prefrontal neurons do follow a specific functional organization-they have a small-world topology. However, until now it has not been possible to directly link small-world topologies to specific circuit functions, e.g., sequence generation. Therefore, we developed a novel analysis to address this issue. Specifically, we constructed surrogate data sets that have identical levels of network activity at every point in time but nevertheless represent various network topologies. We call this method shuffling activity to rearrange correlations (SHARC). We found that only surrogate data sets based on the actual small-world functional organization of prefrontal microcircuits were able to reproduce the levels of sequences observed in actual data. As expected, small-world data sets contained many more sequences than surrogate data sets with randomly arranged correlations. Surprisingly, small-world data sets also outperformed data sets in which correlations were maximally clustered. Thus the small-world functional organization of cortical microcircuits, which effectively balances the random and maximally clustered regimes, is optimal for producing stereotyped sequential patterns of activity.
Collapse
Affiliation(s)
- Francisco J Luongo
- Department of Psychiatry, University of California, San Francisco, California; Center for Integrative Neuroscience, University of California, San Francisco, California; Sloan-Swartz Center for Theoretical Neurobiology, University of California, San Francisco, California; and Neuroscience Graduate Program, University of California, San Francisco, California
| | - Chris A Zimmerman
- Neuroscience Graduate Program, University of California, San Francisco, California
| | - Meryl E Horn
- Neuroscience Graduate Program, University of California, San Francisco, California
| | - Vikaas S Sohal
- Department of Psychiatry, University of California, San Francisco, California; Center for Integrative Neuroscience, University of California, San Francisco, California; Sloan-Swartz Center for Theoretical Neurobiology, University of California, San Francisco, California; and
| |
Collapse
|
52
|
Hamm V, Héraud C, Cassel JC, Mathis C, Goutagny R. Precocious Alterations of Brain Oscillatory Activity in Alzheimer's Disease: A Window of Opportunity for Early Diagnosis and Treatment. Front Cell Neurosci 2015; 9:491. [PMID: 26733816 PMCID: PMC4685112 DOI: 10.3389/fncel.2015.00491] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 12/04/2015] [Indexed: 12/31/2022] Open
Abstract
Alzheimer's disease (AD) is the most common form of neurodegenerative dementia accounting for 50-80% of all age-related dementia. This pathology is characterized by the progressive and irreversible alteration of cognitive functions, such as memory, leading inexorably to the loss of autonomy for patients with AD. The pathology is linked with aging and occurs most commonly around 65 years old. Its prevalence (5% over 65 years of age and 20% after 80 years) constitutes an economic and social burden for AD patients and their family. At the present, there is still no cure for AD, actual treatments being moderately effective only in early stages of the pathology. A lot of efforts have been deployed with the aim of defining new AD biomarkers. Successful early detection of mild cognitive impairment (MCI) linked to AD requires the identification of biomarkers capable of distinguishing individuals with early stages of AD from other pathologies impacting cognition such as depression. In this article, we will review recent evidence suggesting that electroencephalographic (EEG) recordings, coupled with behavioral assessments, could be a useful approach and easily implementable for a precocious detection of AD.
Collapse
Affiliation(s)
- Valentine Hamm
- Centre National de la Recherche Scientifique UMR 7364, Laboratoire de Neurosciences Cognitives et AdaptativesStrasbourg, France; Université de Strasbourg, Neuropôle de StrasbourgStrasbourg, France
| | - Céline Héraud
- Centre National de la Recherche Scientifique UMR 7364, Laboratoire de Neurosciences Cognitives et AdaptativesStrasbourg, France; Université de Strasbourg, Neuropôle de StrasbourgStrasbourg, France
| | - Jean-Christophe Cassel
- Centre National de la Recherche Scientifique UMR 7364, Laboratoire de Neurosciences Cognitives et AdaptativesStrasbourg, France; Université de Strasbourg, Neuropôle de StrasbourgStrasbourg, France
| | - Chantal Mathis
- Centre National de la Recherche Scientifique UMR 7364, Laboratoire de Neurosciences Cognitives et AdaptativesStrasbourg, France; Université de Strasbourg, Neuropôle de StrasbourgStrasbourg, France
| | - Romain Goutagny
- Centre National de la Recherche Scientifique UMR 7364, Laboratoire de Neurosciences Cognitives et AdaptativesStrasbourg, France; Université de Strasbourg, Neuropôle de StrasbourgStrasbourg, France
| |
Collapse
|
53
|
Dinocourt C, Legrand M, Dublineau I, Lestaevel P. The neurotoxicology of uranium. Toxicology 2015; 337:58-71. [PMID: 26277741 DOI: 10.1016/j.tox.2015.08.004] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 08/05/2015] [Accepted: 08/11/2015] [Indexed: 11/26/2022]
Abstract
The brain is a target of environmental toxic pollutants that impair cerebral functions. Uranium is present in the environment as a result of natural deposits and release by human applications. The first part of this review describes the passage of uranium into the brain, and its effects on neurological functions and cognitive abilities. Very few human studies have looked at its cognitive effects. Experimental studies show that after exposure, uranium can reach the brain and lead to neurobehavioral impairments, including increased locomotor activity, perturbation of the sleep-wake cycle, decreased memory, and increased anxiety. The mechanisms underlying these neurobehavioral disturbances are not clearly understood. It is evident that there must be more than one toxic mechanism and that it might include different targets in the brain. In the second part, we therefore review the principal mechanisms that have been investigated in experimental models: imbalance of the anti/pro-oxidant system and neurochemical and neurophysiological pathways. Uranium effects are clearly specific according to brain area, dose, and time. Nonetheless, this review demonstrates the paucity of data about its effects on developmental processes and the need for more attention to the consequences of exposure during development.
Collapse
Affiliation(s)
- Céline Dinocourt
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Pôle de la Radioprotection de l'Homme, Service de Radiobiologie et d'Epidémiologie, Laboratoire de Radiotoxicologie Expérimentale, BP 17, F-92262 Fontenay-aux-Roses, France.
| | - Marie Legrand
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Pôle de la Radioprotection de l'Homme, Service de Radiobiologie et d'Epidémiologie, Laboratoire de Radiotoxicologie Expérimentale, BP 17, F-92262 Fontenay-aux-Roses, France.
| | - Isabelle Dublineau
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Pôle de la Radioprotection de l'Homme, Service de Radiobiologie et d'Epidémiologie, Laboratoire de Radiotoxicologie Expérimentale, BP 17, F-92262 Fontenay-aux-Roses, France.
| | - Philippe Lestaevel
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Pôle de la Radioprotection de l'Homme, Service de Radiobiologie et d'Epidémiologie, Laboratoire de Radiotoxicologie Expérimentale, BP 17, F-92262 Fontenay-aux-Roses, France.
| |
Collapse
|
54
|
Bocian R, Kazmierska P, Kłos-Wojtczak P, Kowalczyk T, Konopacki J. Orexinergic theta rhythm in the rat hippocampal formation: In vitro and in vivo findings. Hippocampus 2015; 25:1393-406. [PMID: 25820995 DOI: 10.1002/hipo.22459] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/17/2015] [Indexed: 02/02/2023]
Abstract
Previous in vivo data suggested that orexin neuropeptides (ORX(A) and ORX(B) ) synthetized in hypothalamic neurons were involved in the mechanism of generation of the hippocampal formation theta rhythm. Surprisingly, this suggestion has never been directly proved by experiments using intraseptal or intrahippocampal administration of orexins. In this study, involving the use of in vitro hippocampal formation slices and in vivo model of anesthetized rat, we provide the first convergent electropharmacological evidence that in the presence of both ORX(A) and ORX(B) the hippocampal formation neuronal network is capable of producing oscillations in the theta band. This effect of orexin peptides was antagonized by selective blockers of orexin receptors (OX1 R and OX2 R), SB 334867 and TCS OX2 29, respectively. These results provide evidence for a novel, orexinergic mechanism responsible for the production of theta rhythm in the hippocampal formation neuronal network.
Collapse
Affiliation(s)
- Renata Bocian
- Department of Neurobiology, Faculty of Biology and Environmental Protection, University of Lodz, Poland
| | - Paulina Kazmierska
- Department of Neurobiology, Faculty of Biology and Environmental Protection, University of Lodz, Poland
| | - Paulina Kłos-Wojtczak
- Department of Neurobiology, Faculty of Biology and Environmental Protection, University of Lodz, Poland
| | - Tomasz Kowalczyk
- Department of Neurobiology, Faculty of Biology and Environmental Protection, University of Lodz, Poland
| | - Jan Konopacki
- Department of Neurobiology, Faculty of Biology and Environmental Protection, University of Lodz, Poland
| |
Collapse
|
55
|
Wang Y, Wang Z, Wang J, Wang Y, Henderson Z, Wang X, Zhang X, Song J, Lu C. The modulation of nicotinic acetylcholine receptors on the neuronal network oscillations in rat hippocampal CA3 area. Sci Rep 2015; 5:9493. [PMID: 25810076 PMCID: PMC4374140 DOI: 10.1038/srep09493] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 03/05/2015] [Indexed: 11/28/2022] Open
Abstract
γ oscillations are associated with higher brain functions such as memory, perception and consciousness. Disruption of γ oscillations occur in various neuro-psychological disorders such as schizophrenia. Nicotinic acetylcholine receptors (nAChR) are highly expressed in the hippocampus, however, little is known about the role on hippocampal persistent γ oscillation. This study examined the effects of nicotine and selective nAChR agonists and antagonists on kainate-induced persistent γ oscillation in rat hippocampal slices. Nicotine enhanced γ oscillation at concentrations of 0.1–10 μM, but reduced it at a higher concentration of 100 μM. The enhancement on γ oscillation can be best mimicked by co-application of α4β2- and α7- nAChR agonist and reduced by a combination of nAChR antagonists, DhβE and MLA. However, these nAChR antagonists failed to block the suppressing role of nicotine on γ. Furthermore, we found that the NMDA receptor antagonist D-AP5 completely blocked the effect of nicotine. These results demonstrate that nicotine modulates γ oscillations via α7 and α4β2 nAChR as well as NMDA activation, suggesting that nAChR activation may have a therapeutic role for the clinical disorder such as schizophrenia, which is known to have impaired γ oscillation and hypo-NMDA receptor function.
Collapse
Affiliation(s)
- Yang Wang
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical University, Henan Province, Henan PR. China
| | - Zhan Wang
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical University, Henan Province, Henan PR. China
| | - Jiangang Wang
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical University, Henan Province, Henan PR. China
| | - Yali Wang
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical University, Henan Province, Henan PR. China
| | - Zaineb Henderson
- Institute of Membrane and System Biology, University of Leeds, Leeds, England
| | - Xiaofang Wang
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical University, Henan Province, Henan PR. China
| | - Xi Zhang
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical University, Henan Province, Henan PR. China
| | - Jinggui Song
- Psychiatric Hospital of Henan Province, 2nd Affiliated Hospital of Xinxiang Medical University
| | - Chengbiao Lu
- 1] Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical University, Henan Province, Henan PR. China [2] Psychiatric Hospital of Henan Province, 2nd Affiliated Hospital of Xinxiang Medical University
| |
Collapse
|
56
|
Schneider J, Lewen A, Ta TT, Galow LV, Isola R, Papageorgiou IE, Kann O. A reliable model for gamma oscillations in hippocampal tissue. J Neurosci Res 2015; 93:1067-78. [PMID: 25808046 DOI: 10.1002/jnr.23590] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 02/16/2015] [Accepted: 02/27/2015] [Indexed: 12/13/2022]
Abstract
Gamma oscillations (30-100 Hz) reflect a fast brain rhythm that provides a fundamental mechanism of complex neuronal information processing in the hippocampus and in the neocortex in vivo. Gamma oscillations have been implicated in higher brain functions, such as sensory perception, motor activity, and memory formation. Experimental studies on synaptic transmission and bioenergetics underlying gamma oscillations have primarily used acute slices of the hippocampus. This study tests whether organotypic hippocampal slice cultures of the rat provide an alternative model for cortical gamma oscillations in vitro. Our findings are that 1) slice cultures feature well-preserved laminated architecture and neuronal morphology; 2) slice cultures of different maturation stages (7-28 days in vitro) reliably express gamma oscillations at about 40 Hz as induced by cholinergic (acetylcholine) or glutamatergic (kainate) receptor agonists; 3) the peak frequency of gamma oscillations depends on the temperature, with an increase of ∼ 3.5 Hz per degree Celsius for the range of 28-36 °C; 4) most slice cultures show persistent gamma oscillations for ∼ 1 hr during electrophysiological local field potential recordings, and later alterations may occur; and 5) in slice cultures, glucose at a concentration of 5 mM in the recording solution is sufficient to power gamma oscillations, and additional energy substrate supply with monocarboxylate metabolite lactate (2 mM) exclusively increases the peak frequency by ∼ 4 Hz. This study shows that organotypic hippocampal slice cultures provide a reliable model to study agonist-induced gamma oscillations at glucose levels near the physiological range.
Collapse
Affiliation(s)
- Justus Schneider
- Institute of Physiology and Pathophysiology and Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
| | - Andrea Lewen
- Institute of Physiology and Pathophysiology and Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
| | - Thuy-Truc Ta
- Institute of Physiology and Pathophysiology and Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
| | - Lukas V Galow
- Institute of Physiology and Pathophysiology and Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
| | - Raffaella Isola
- Institute of Physiology and Pathophysiology and Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
| | - Ismini E Papageorgiou
- Institute of Physiology and Pathophysiology and Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
| | - Oliver Kann
- Institute of Physiology and Pathophysiology and Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
| |
Collapse
|
57
|
Balakrishnan S, Pearce RA. Spatiotemporal characteristics and pharmacological modulation of multiple gamma oscillations in the CA1 region of the hippocampus. Front Neural Circuits 2015; 8:150. [PMID: 25628540 PMCID: PMC4290596 DOI: 10.3389/fncir.2014.00150] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 12/16/2014] [Indexed: 01/28/2023] Open
Abstract
Multiple components of "γ-oscillations" between 30-170 Hz in the CA1 region of the hippocampus have been described, based on their coherence with oscillations in other brain regions and on their cross-frequency coupling with local θ-oscillations. However, it remains unclear whether the different sub-bands are generated by a single broadband oscillator coupled to multiple external inputs, or by separate oscillators that incorporate distinct circuit elements. To distinguish between these possibilities, we used high-density linear array recording electrodes in awake behaving mice to examine the spatiotemporal characteristics of γ-oscillations and their responses to midazolam and atropine. We characterized oscillations using current source density (CSD) analysis, and measured θ-γ phase-amplitude coupling by cross frequency coupling (CFC) analysis. Prominent peaks were present in the CSD signal in the mid- and distal apical dendritic layers at all frequencies, and at stratum pyramidale for γ(slow) (30-45 Hz) and γ(mid) (50-90 Hz), but not γ(fast) (90-170 Hz) oscillations. Differences in the strength and timing of θ-γ(slow) and θ-γ(mid) cross frequency coupling, and a lack of coupling at the soma and mid-apical region for γ(fast) oscillations, indicated that separate circuit components generate the three sub-bands. Midazolam altered CSD amplitudes and cross-frequency coupling in a lamina- and frequency specific manner, providing further evidence for separate generator circuits. Atropine altered CSD amplitudes and θ-γ CFC uniformly at all locations. Simulations using a detailed compartmental model were consistent with γ(slow) and γ(mid) oscillations driven primarily by inputs at the mid-apical dendrites, and γ(fast) at the distal apical dendrite. Our results indicate that multiple distinct local circuits generate γ-oscillations in the CA1 region of the hippocampus, and provide detailed information about their spatiotemporal characteristics.
Collapse
Affiliation(s)
- Shilpashree Balakrishnan
- Neuroscience Training Program, University of Wisconsin-Madison Madison, WI, USA ; Department of Anesthesiology, University of Wisconsin-Madison Madison, WI, USA
| | - Robert A Pearce
- Department of Anesthesiology, University of Wisconsin-Madison Madison, WI, USA
| |
Collapse
|
58
|
Ahnaou A, Huysmans H, Jacobs T, Drinkenburg W. Cortical EEG oscillations and network connectivity as efficacy indices for assessing drugs with cognition enhancing potential. Neuropharmacology 2014; 86:362-77. [DOI: 10.1016/j.neuropharm.2014.08.015] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 08/18/2014] [Accepted: 08/20/2014] [Indexed: 10/24/2022]
|
59
|
Lundstrom BN. Modeling multiple time scale firing rate adaptation in a neural network of local field potentials. J Comput Neurosci 2014; 38:189-202. [PMID: 25319064 DOI: 10.1007/s10827-014-0536-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 10/05/2014] [Accepted: 10/08/2014] [Indexed: 11/30/2022]
Abstract
In response to stimulus changes, the firing rates of many neurons adapt, such that stimulus change is emphasized. Previous work has emphasized that rate adaptation can span a wide range of time scales and produce time scale invariant power law adaptation. However, neuronal rate adaptation is typically modeled using single time scale dynamics, and constructing a conductance-based model with arbitrary adaptation dynamics is nontrivial. Here, a modeling approach is developed in which firing rate adaptation, or spike frequency adaptation, can be understood as a filtering of slow stimulus statistics. Adaptation dynamics are modeled by a stimulus filter, and quantified by measuring the phase leads of the firing rate in response to varying input frequencies. Arbitrary adaptation dynamics are approximated by a set of weighted exponentials with parameters obtained by fitting to a desired filter. With this approach it is straightforward to assess the effect of multiple time scale adaptation dynamics on neural networks. To demonstrate this, single time scale and power law adaptation were added to a network model of local field potentials. Rate adaptation enhanced the slow oscillations of the network and flattened the output power spectrum, dampening intrinsic network frequencies. Thus, rate adaptation may play an important role in network dynamics.
Collapse
|
60
|
Abstract
Glial cells are an integral part of functional communication in the brain. Here we show that astrocytes contribute to the fast dynamics of neural circuits that underlie normal cognitive behaviors. In particular, we found that the selective expression of tetanus neurotoxin (TeNT) in astrocytes significantly reduced the duration of carbachol-induced gamma oscillations in hippocampal slices. These data prompted us to develop a novel transgenic mouse model, specifically with inducible tetanus toxin expression in astrocytes. In this in vivo model, we found evidence of a marked decrease in electroencephalographic (EEG) power in the gamma frequency range in awake-behaving mice, whereas neuronal synaptic activity remained intact. The reduction in cortical gamma oscillations was accompanied by impaired behavioral performance in the novel object recognition test, whereas other forms of memory, including working memory and fear conditioning, remained unchanged. These results support a key role for gamma oscillations in recognition memory. Both EEG alterations and behavioral deficits in novel object recognition were reversed by suppression of tetanus toxin expression. These data reveal an unexpected role for astrocytes as essential contributors to information processing and cognitive behavior.
Collapse
|
61
|
Yi F, Ball J, Stoll KE, Satpute VC, Mitchell SM, Pauli JL, Holloway BB, Johnston AD, Nathanson NM, Deisseroth K, Gerber DJ, Tonegawa S, Lawrence JJ. Direct excitation of parvalbumin-positive interneurons by M1 muscarinic acetylcholine receptors: roles in cellular excitability, inhibitory transmission and cognition. J Physiol 2014; 592:3463-94. [PMID: 24879872 DOI: 10.1113/jphysiol.2014.275453] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Parvalbumin-containing (PV) neurons, a major class of GABAergic interneurons, are essential circuit elements of learning networks. As levels of acetylcholine rise during active learning tasks, PV neurons become increasingly engaged in network dynamics. Conversely, impairment of either cholinergic or PV interneuron function induces learning deficits. Here, we examined PV interneurons in hippocampus (HC) and prefrontal cortex (PFC) and their modulation by muscarinic acetylcholine receptors (mAChRs). HC PV cells, visualized by crossing PV-CRE mice with Rosa26YFP mice, were anatomically identified as basket cells and PV bistratified cells in the stratum pyramidale; in stratum oriens, HC PV cells were electrophysiologically distinct from somatostatin-containing cells. With glutamatergic transmission pharmacologically blocked, mAChR activation enhanced PV cell excitability in both CA1 HC and PFC; however, CA1 HC PV cells exhibited a stronger postsynaptic depolarization than PFC PV cells. To delete M1 mAChRs genetically from PV interneurons, we created PV-M1 knockout mice by crossing PV-CRE and floxed M1 mice. The elimination of M1 mAChRs from PV cells diminished M1 mAChR immunoreactivity and muscarinic excitation of HC PV cells. Selective cholinergic activation of HC PV interneurons using Designer Receptors Exclusively Activated by Designer Drugs technology enhanced the frequency and amplitude of inhibitory synaptic currents in CA1 pyramidal cells. Finally, relative to wild-type controls, PV-M1 knockout mice exhibited impaired novel object recognition and, to a lesser extent, impaired spatial working memory, but reference memory remained intact. Therefore, the direct activation of M1 mAChRs on PV cells contributes to some forms of learning and memory.
Collapse
Affiliation(s)
- Feng Yi
- COBRE Center for Structural and Functional Neuroscience Department of Biomedical and Pharmaceutical Sciences
| | - Jackson Ball
- COBRE Center for Structural and Functional Neuroscience Department of Biomedical and Pharmaceutical Sciences
| | - Kurt E Stoll
- COBRE Center for Structural and Functional Neuroscience Department of Biomedical and Pharmaceutical Sciences
| | - Vaishali C Satpute
- COBRE Center for Structural and Functional Neuroscience Department of Biomedical and Pharmaceutical Sciences Neuroscience Graduate Program
| | - Samantha M Mitchell
- COBRE Center for Structural and Functional Neuroscience Department of Biomedical and Pharmaceutical Sciences Davidson Honors College, The University of Montana, Missoula, MT 59812, USA
| | - Jordan L Pauli
- COBRE Center for Structural and Functional Neuroscience Department of Biomedical and Pharmaceutical Sciences
| | - Benjamin B Holloway
- COBRE Center for Structural and Functional Neuroscience Department of Biomedical and Pharmaceutical Sciences
| | - April D Johnston
- COBRE Center for Structural and Functional Neuroscience Department of Biomedical and Pharmaceutical Sciences
| | - Neil M Nathanson
- Department of Pharmacology, University of Washington, Box 357750, Seattle, WA 98195-7750, USA
| | - Karl Deisseroth
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - David J Gerber
- Howard Hughes Medical Institute, RIKEN-MIT Neuroscience Research Center, The Picower Institute for Learning and Memory, Department of Biology and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Susumu Tonegawa
- Howard Hughes Medical Institute, RIKEN-MIT Neuroscience Research Center, The Picower Institute for Learning and Memory, Department of Biology and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - J Josh Lawrence
- COBRE Center for Structural and Functional Neuroscience Department of Biomedical and Pharmaceutical Sciences
| |
Collapse
|
62
|
Konopacki J, Bocian R, Kowalczyk T, Kłos-Wojtczak P. The electrical coupling and the hippocampal formation theta rhythm in rats. Brain Res Bull 2014; 107:1-17. [PMID: 24747291 DOI: 10.1016/j.brainresbull.2014.04.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 04/03/2014] [Accepted: 04/08/2014] [Indexed: 02/05/2023]
Abstract
Gap junctions (GJs) were discovered more than five decades ago, and since that time enormous strides have been made in understanding their structure and function. Despite the voluminous literature concerning the function of GJs, the involvement of these membrane structures in the central mechanisms underlying oscillations and synchrony in the neuronal network is still a matter of intensive debate. This review summarizes what is known concerning the involvement of GJs as electrical synapses in mechanisms underlying the generation of theta band oscillations. The first part of the chapter discusses the role of GJs in mechanisms of oscillations and synchrony. Following this, in vitro, ex vivo, and in vivo experiments concerning the involvement of GJs in the generation of hippocampal formation theta in rats are reviewed.
Collapse
Affiliation(s)
- Jan Konopacki
- Department of Neurobiology, The University of Lodz, Poland.
| | - Renata Bocian
- Department of Neurobiology, The University of Lodz, Poland
| | | | | |
Collapse
|
63
|
Shin D, Cho KH. Recurrent connections form a phase-locking neuronal tuner for frequency-dependent selective communication. Sci Rep 2014; 3:2519. [PMID: 23981983 PMCID: PMC3755292 DOI: 10.1038/srep02519] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 08/12/2013] [Indexed: 11/16/2022] Open
Abstract
The brain requires task-dependent interregional coherence of information flow in the anatomically connected neural network. However, it is still unclear how a neuronal group can flexibly select its communication target. In this study, we revealed a hidden routing mechanism on the basis of recurrent connections. Our simulation results based on the spike response model show that recurrent connections between excitatory and inhibitory neurons modulate the resonant frequency of a local neuronal group, and that this modulation enables a neuronal group to receive selective information by filtering a preferred frequency component. We also found that the recurrent connection facilitates the successful routing of any necessary information flow between neuronal groups through frequency-dependent resonance of synchronized oscillations. Taken together, these results suggest that recurrent connections act as a phase-locking neuronal tuner which determines the resonant frequency of a local group and thereby controls the preferential routing of incoming signals.
Collapse
Affiliation(s)
- Dongkwan Shin
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Republic of Korea
| | | |
Collapse
|
64
|
Rangaswamy M, Porjesz B. Understanding alcohol use disorders with neuroelectrophysiology. HANDBOOK OF CLINICAL NEUROLOGY 2014; 125:383-414. [PMID: 25307587 DOI: 10.1016/b978-0-444-62619-6.00023-9] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Neurocognitive deficits associated with impairments in various brain regions and neural circuitries, particularly involving frontal lobes, have been associated with chronic alcoholism, as well as with a predisposition to develop alcohol use and related disorders (AUDs). AUD is a multifactorial disorder caused by complex interactions between behavioral, genetic, and environmental liabilities. Neuroelectrophysiologic techniques are instrumental in understanding brain and behavior relationships and have also proved very useful in evaluating the genetic diathesis of alcoholism. This chapter describes findings from neuroelectrophysiologic measures (electroencephalogram, event-related potentials, and event-related oscillations) related to acute and chronic effects of alcohol on the brain and those that reflect underlying deficits related to a predisposition to develop AUDs and related disorders. The utility of these measures as effective endophenotypes to identify and understand genes associated with brain electrophysiology, cognitive networks, and AUDs has also been discussed.
Collapse
Affiliation(s)
- Madhavi Rangaswamy
- Henri Begleiter Neurodynamics Laboratory, Department of Psychiatry and Behavioral Sciences, SUNY Downstate Medical Center, Brooklyn, NY, USA
| | - Bernice Porjesz
- Henri Begleiter Neurodynamics Laboratory, Department of Psychiatry and Behavioral Sciences, SUNY Downstate Medical Center, Brooklyn, NY, USA.
| |
Collapse
|
65
|
Pietersen ANJ, Ward PD, Hagger-Vaughan N, Wiggins J, Jefferys JGR, Vreugdenhil M. Transition between fast and slow gamma modes in rat hippocampus area CA1 in vitro is modulated by slow CA3 gamma oscillations. J Physiol 2013; 592:605-20. [PMID: 24277864 DOI: 10.1113/jphysiol.2013.263889] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Hippocampal gamma oscillations have been associated with cognitive functions including navigation and memory encoding/retrieval. Gamma oscillations in area CA1 are thought to depend on the oscillatory drive from CA3 (slow gamma) or the entorhinal cortex (fast gamma). Here we show that the local CA1 network can generate its own fast gamma that can be suppressed by slow gamma-paced inputs from CA3. Moderate acetylcholine receptor activation induces fast (45 ± 1 Hz) gamma in rat CA1 minislices and slow (33 ± 1 Hz) gamma in CA3 minislices in vitro. Using pharmacological tools, current-source density analysis and intracellular recordings from pyramidal cells and fast-spiking stratum pyramidale interneurons, we demonstrate that fast gamma in CA1 is of the pyramidal-interneuron network gamma (PING) type, with the firing of principal cells paced by recurrent perisomal IPSCs. The oscillation frequency was only weakly dependent on IPSC amplitude, and decreased to that of CA3 slow gamma by reducing IPSC decay rate or reducing interneuron activation through tonic inhibition of interneurons. Fast gamma in CA1 was replaced by slow CA3-driven gamma in unlesioned slices, which could be mimicked in CA1 minislices by sub-threshold 35 Hz Schaffer collateral stimulation that activated fast-spiking interneurons but hyperpolarised pyramidal cells, suggesting that slow gamma frequency CA3 outputs can suppress the CA1 fast gamma-generating network by feed-forward inhibition and replaces it with a slower gamma oscillation driven by feed-forward inhibition. The transition between the two gamma oscillation modes in CA1 might allow it to alternate between effective communication with the medial entorhinal cortex and CA3, which have different roles in encoding and recall of memory.
Collapse
Affiliation(s)
- Alexander N J Pietersen
- Neuronal Networks group, School of Clinical and Experimental Medicine, University of Birmingham, B15 2TT, Birmingham, UK.
| | | | | | | | | | | |
Collapse
|
66
|
Kazmierska P, Konopacki J. Development of NMDA-induced theta rhythm in hippocampal formation slices. Brain Res Bull 2013; 98:93-101. [DOI: 10.1016/j.brainresbull.2013.07.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 07/11/2013] [Accepted: 07/18/2013] [Indexed: 10/26/2022]
|
67
|
NMDA-dependent phase synchronization between septal and temporal CA3 hippocampal networks. J Neurosci 2013; 33:8276-87. [PMID: 23658168 DOI: 10.1523/jneurosci.0179-13.2013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Increasing evidence suggests that synchronization between brain regions is essential for information exchange and memory processes. However, it remains incompletely known which synaptic mechanisms contribute to the process of synchronization. Here, we investigated whether NMDA receptor-mediated synaptic plasticity was an important player in synchronization between septal and temporal CA3 areas of the rat hippocampus. We found that both the septal and temporal CA3 regions intrinsically generate weakly synchronized δ frequency oscillations in the complete hippocampus in vitro. Septal and temporal oscillators differed in frequency, power, and rhythmicity, but both required GABAA and AMPA receptors. NMDA receptor activation, and most particularly the NR2B subunit, contributed considerably more to rhythm generation at the temporal than the septal region. Brief activation of NMDA receptors by application of extracellular calcium dramatically potentiated the septal-temporal coherence for long durations (>40 min), an effect blocked by the NMDA antagonist AP-5. This long-lasting NMDA-receptor-dependent increase in coherence was also associated with an elevated phase locking of spikes locally and across regions. Changes in coherence between oscillators were associated with increases in phase locking between oscillators independent of oscillator amplitude. Finally, although the septal CA3 rhythm preceded the oscillations in temporal regions in control conditions, this was reversed during the NMDA-dependent enhancement in coherence, suggesting that NMDA receptor activation can change the direction of information flow along the septotemporal CA3 axis. These data demonstrate that plastic changes in communication between septal and temporal hippocampal regions can arise from the NMDA-dependent phase locking of neural oscillators.
Collapse
|
68
|
Kowalczyk T, Bocian R, Caban B, Konopacki J. Atropine-sensitive theta rhythm in the posterior hypothalamic area: in vivo and in vitro studies. Hippocampus 2013; 24:7-20. [PMID: 23836546 DOI: 10.1002/hipo.22167] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 06/11/2013] [Accepted: 06/24/2013] [Indexed: 11/06/2022]
Abstract
Theta rhythm is the largest, most prominent, and well-documented electroencephalography activity present in a number of mammals, including humans. Spontaneous theta activity recorded locally in the posterior hypothalamic area (PHa) has never been the subject of detailed studies. The authors have shown that local theta field potentials could be generated in urethane-anesthetized rats in the supramammillary (SuM) nuclei and posterior hypothalamic (PH) nuclei. Theta recorded in the PHa was produced independently of simultaneously occurring hippocampal theta. These data were confirmed in the PHa maintained in vitro. Local theta field activity was recorded in the SuM and PH nuclei of PHa slice preparations perfused with cholinergic agonist carbachol. Both in vivo and in vitro recorded PHa theta rhythmicity had a cholinergic-muscarinic profile, that is, it was antagonized by muscarinic antagonist atropine sulfate.
Collapse
Affiliation(s)
- Tomasz Kowalczyk
- Department of Neurobiology, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland
| | | | | | | |
Collapse
|
69
|
Amyloid Beta peptides differentially affect hippocampal theta rhythms in vitro. INTERNATIONAL JOURNAL OF PEPTIDES 2013; 2013:328140. [PMID: 23878547 PMCID: PMC3708430 DOI: 10.1155/2013/328140] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2013] [Accepted: 06/03/2013] [Indexed: 12/27/2022]
Abstract
Soluble amyloid beta peptide (A β ) is responsible for the early cognitive dysfunction observed in Alzheimer's disease. Both cholinergically and glutamatergically induced hippocampal theta rhythms are related to learning and memory, spatial navigation, and spatial memory. However, these two types of theta rhythms are not identical; they are associated with different behaviors and can be differentially modulated by diverse experimental conditions. Therefore, in this study, we aimed to investigate whether or not application of soluble A β alters the two types of theta frequency oscillatory network activity generated in rat hippocampal slices by application of the cholinergic and glutamatergic agonists carbachol or DHPG, respectively. Due to previous evidence that oscillatory activity can be differentially affected by different A β peptides, we also compared Aβ 25-35 and Aβ 1-42 for their effects on theta rhythms in vitro at similar concentrations (0.5 to 1.0 μ M). We found that Aβ 25-35 reduces, with less potency than Aβ 1-42, carbachol-induced population theta oscillatory activity. In contrast, DHPG-induced oscillatory activity was not affected by a high concentration of Aβ 25-35 but was reduced by Aβ 1-42. Our results support the idea that different amyloid peptides might alter specific cellular mechanisms related to the generation of specific neuronal network activities, instead of exerting a generalized inhibitory effect on neuronal network function.
Collapse
|
70
|
Nicotinic modulation of intrinsic brain networks in schizophrenia. Biochem Pharmacol 2013; 86:1163-72. [PMID: 23796751 DOI: 10.1016/j.bcp.2013.06.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 06/13/2013] [Accepted: 06/14/2013] [Indexed: 12/13/2022]
Abstract
The nicotinic receptor is a promising drug target currently being investigated for the treatment of cognitive symptoms in schizophrenia. A key step in this process is the development of noninvasive functional neuroimaging biomarkers that can be used to determine if nicotinic agents are eliciting their targeted biological effect, ideally through modulation of a fundamental aspect of neuronal function. To that end, neuroimaging researchers are beginning to understand how nicotinic modulation affects "intrinsic" brain networks to elicit potentially therapeutic effects. An intrinsic network is a functionally and (often) structurally connected network of brain areas whose activity reflects a fundamental neurobiological organizational principle of the brain. This review summarizes findings of the effects of nicotinic drugs on three topics related to intrinsic brain network activity: (1) the default mode network, a group of brain areas for which activity is maximal at rest and reduced during cognitive tasks, (2) the salience network, which integrates incoming sensory data with prior internal representations to guide future actions and change predictive values, and (3) multi-scale complex network dynamics, which describe these brain's ability to efficiency integrate information while preserving local functional specialization. These early findings can be used to inform future neuroimaging studies that examine the network effects of nicotinic agents.
Collapse
|
71
|
Anisuzzaman ASM, Uwada J, Masuoka T, Yoshiki H, Nishio M, Ikegaya Y, Takahashi N, Matsuki N, Fujibayashi Y, Yonekura Y, Momiyama T, Muramatsu I. Novel contribution of cell surface and intracellular M1-muscarinic acetylcholine receptors to synaptic plasticity in hippocampus. J Neurochem 2013; 126:360-71. [DOI: 10.1111/jnc.12306] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 04/30/2013] [Accepted: 05/14/2013] [Indexed: 01/08/2023]
Affiliation(s)
- Abu Syed Md Anisuzzaman
- Division of Pharmacology; Department of Biochemistry and Bioinformative Sciences; School of Medicine; University of Fukui; Eiheiji Japan
| | - Junsuke Uwada
- Division of Pharmacology; Department of Biochemistry and Bioinformative Sciences; School of Medicine; University of Fukui; Eiheiji Japan
- Organization for Life Science Advancement Programs; University of Fukui; Eiheiji Japan
| | - Takayoshi Masuoka
- Department of Pharmacology; School of Medicine; Kanazawa Medical University; Uchinada Japan
| | - Hatsumi Yoshiki
- Division of Pharmacology; Department of Biochemistry and Bioinformative Sciences; School of Medicine; University of Fukui; Eiheiji Japan
| | - Matomo Nishio
- Department of Pharmacology; School of Medicine; Kanazawa Medical University; Uchinada Japan
| | - Yuji Ikegaya
- Laboratory of Chemical Pharmacology; Graduate School of Pharmaceutical Sciences; The University of Tokyo; Hongo Bunkyo-ku Japan
| | - Naoya Takahashi
- Laboratory of Chemical Pharmacology; Graduate School of Pharmaceutical Sciences; The University of Tokyo; Hongo Bunkyo-ku Japan
| | - Norio Matsuki
- Laboratory of Chemical Pharmacology; Graduate School of Pharmaceutical Sciences; The University of Tokyo; Hongo Bunkyo-ku Japan
| | | | | | - Toshihiko Momiyama
- Department of Pharmacology; Jikei University School of Medicine; Minato-ku Japan
| | - Ikunobu Muramatsu
- Division of Pharmacology; Department of Biochemistry and Bioinformative Sciences; School of Medicine; University of Fukui; Eiheiji Japan
- Organization for Life Science Advancement Programs; University of Fukui; Eiheiji Japan
- Child Development Research Center; Graduate School of Medicine; University of Fukui; Eiheiji Japan
| |
Collapse
|
72
|
Abstract
Theta and gamma frequency oscillations occur in the same brain regions and interact with each other, a process called cross-frequency coupling. Here, we review evidence for the following hypothesis: that the dual oscillations form a code for representing multiple items in an ordered way. This form of coding has been most clearly demonstrated in the hippocampus, where different spatial information is represented in different gamma subcycles of a theta cycle. Other experiments have tested the functional importance of oscillations and their coupling. These involve correlation of oscillatory properties with memory states, correlation with memory performance, and effects of disrupting oscillations on memory. Recent work suggests that this coding scheme coordinates communication between brain regions and is involved in sensory as well as memory processes.
Collapse
Affiliation(s)
- John E. Lisman
- Brandeis University, Biology Department & Volen Center for Complex Systems, 415 South Street-MS 008, Waltham, MA 02454-9110, 781-736-3145
| | - Ole Jensen
- Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Kapittelweg 29, 6525 EN Nijmegen, The Netherlands
| |
Collapse
|
73
|
Gonzalez JC, Lignani G, Maroto M, Baldelli P, Hernandez-Guijo JM. Presynaptic Muscarinic Receptors Reduce Synaptic Depression and Facilitate its Recovery at Hippocampal GABAergic Synapses. Cereb Cortex 2013; 24:1818-31. [DOI: 10.1093/cercor/bht032] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
|
74
|
Ferchmin PA, Pérez D, Castro Alvarez W, Penzo MA, Maldonado HM, Eterovic VA. γ-Aminobutyric acid type A receptor inhibition triggers a nicotinic neuroprotective mechanism. J Neurosci Res 2012; 91:416-25. [PMID: 23280428 DOI: 10.1002/jnr.23155] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 08/09/2012] [Accepted: 09/14/2012] [Indexed: 01/09/2023]
Abstract
Nicotinic acetylcholine receptor (nAChR)-mediated neuroprotection has been implicated in the treatment of neurodegenerative disorders such as Alzheimer's and Parkinson's diseases and hypoxic ischemic events as well as other diseases hallmarked by excitotoxic and apoptotic neuronal death. Several modalities of nicotinic neuroprotection have been reported. However, although this process generally involves α4β2 and α7 subtypes, the underlying mechanisms are largely unknown. Interestingly, both activation and inhibition of α7 nAChRs have been reported to be neuroprotective. We have shown that inhibition of α7 nAChRs protects the function of acute hippocampal slices against excitotoxicity in an α4β2-dependent manner. Neuroprotection was assessed as the prevention of the N-methyl-D-aspartate-dependent loss of the area of population spikes (PSs) in the CA1 area of acute hippocampal slices. Our results support a model in which α7 AChRs control the release of γ-aminobutyric acid (GABA). Blocking either α7 or GABA(A) receptors reduces the inhibitory tone on cholinergic terminals, thereby promoting α4β2 activation, which in turn mediates neuroprotection. These results shed light on how α7 nAChR inhibition can be neuroprotective through a mechanism mediated by activation of α4β2 nAChRs.
Collapse
Affiliation(s)
- P A Ferchmin
- School of Medicine, Universidad Central del Caribe, Bayamón, Puerto Rico.
| | | | | | | | | | | |
Collapse
|
75
|
Kowalczyk T, Bocian R, Konopacki J. The generation of theta rhythm in hippocampal formation maintainedin vitro. Eur J Neurosci 2012; 37:679-99. [DOI: 10.1111/ejn.12091] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Revised: 11/09/2012] [Accepted: 11/12/2012] [Indexed: 11/28/2022]
Affiliation(s)
- Tomasz Kowalczyk
- Department of Neurobiology; Faculty of Biology and Environmental Protection; University of Lodz; Pomorska Str. No 141/143; 90-236; Lodz; Poland
| | - Renata Bocian
- Department of Neurobiology; Faculty of Biology and Environmental Protection; University of Lodz; Pomorska Str. No 141/143; 90-236; Lodz; Poland
| | - Jan Konopacki
- Department of Neurobiology; Faculty of Biology and Environmental Protection; University of Lodz; Pomorska Str. No 141/143; 90-236; Lodz; Poland
| |
Collapse
|
76
|
Ota K, Omori T, Miyakawa H, Okada M, Aonishi T. Higher-order spike triggered analysis of neural oscillators. PLoS One 2012; 7:e50232. [PMID: 23226249 PMCID: PMC3511465 DOI: 10.1371/journal.pone.0050232] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 10/22/2012] [Indexed: 12/04/2022] Open
Abstract
For the purpose of elucidating the neural coding process based on the neural excitability mechanism, researchers have recently investigated the relationship between neural dynamics and the spike triggered stimulus ensemble (STE). Ermentrout et al. analytically derived the relational equation between the phase response curve (PRC) and the spike triggered average (STA). The STA is the first cumulant of the STE. However, in order to understand the neural function as the encoder more explicitly, it is necessary to elucidate the relationship between the PRC and higher-order cumulants of the STE. In this paper, we give a general formulation to relate the PRC and the nth moment of the STE. By using this formulation, we derive a relational equation between the PRC and the spike triggered covariance (STC), which is the covariance of the STE. We show the effectiveness of the relational equation through numerical simulations and use the equation to identify the feature space of the rat hippocampal CA1 pyramidal neurons from their PRCs. Our result suggests that the hippocampal CA1 pyramidal neurons oscillating in the theta frequency range are commonly sensitive to inputs composed of theta and gamma frequency components.
Collapse
Affiliation(s)
- Keisuke Ota
- Brain Science Institute, RIKEN, Wako-shi, Saitama, Japan
| | - Toshiaki Omori
- Department of Electrical and Electronic Engineering, Kobe University, Kobe-shi, Hyogo, Japan
| | - Hiroyoshi Miyakawa
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan
| | - Masato Okada
- Brain Science Institute, RIKEN, Wako-shi, Saitama, Japan
- Department of Complexity Science and Engineering, The University of Tokyo, Kashiwa-shi, Chiba, Japan
| | - Toru Aonishi
- Department of Computational Intelligence and Systems Science, Tokyo Institute of Technology, Yokohama-shi, Kanagawa, Japan
- * E-mail:
| |
Collapse
|
77
|
Berzhanskaya J, Chernyy N, Gluckman BJ, Schiff SJ, Ascoli GA. Modulation of hippocampal rhythms by subthreshold electric fields and network topology. J Comput Neurosci 2012; 34:369-89. [PMID: 23053863 DOI: 10.1007/s10827-012-0426-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 09/14/2012] [Accepted: 09/17/2012] [Indexed: 11/26/2022]
Abstract
Theta (4-12 Hz) and gamma (30-80 Hz) rhythms are considered important for cortical and hippocampal function. Although several neuron types are implicated in rhythmogenesis, the exact cellular mechanisms remain unknown. Subthreshold electric fields provide a flexible, area-specific tool to modulate neural activity and directly test functional hypotheses. Here we present experimental and computational evidence of the interplay among hippocampal synaptic circuitry, neuronal morphology, external electric fields, and network activity. Electrophysiological data are used to constrain and validate an anatomically and biophysically realistic model of area CA1 containing pyramidal cells and two interneuron types: dendritic- and perisomatic-targeting. We report two lines of results: addressing the network structure capable of generating theta-modulated gamma rhythms, and demonstrating electric field effects on those rhythms. First, theta-modulated gamma rhythms require specific inhibitory connectivity. In one configuration, GABAergic axo-dendritic feedback on pyramidal cells is only effective in proximal but not distal layers. An alternative configuration requires two distinct perisomatic interneuron classes, one exclusively receiving excitatory contacts, the other additionally targeted by inhibition. These observations suggest novel roles for particular classes of oriens and basket cells. The second major finding is that subthreshold electric fields robustly alter the balance between different rhythms. Independent of network configuration, positive electric fields decrease, while negative fields increase the theta/gamma ratio. Moreover, electric fields differentially affect average theta frequency depending on specific synaptic connectivity. These results support the testable prediction that subthreshold electric fields can alter hippocampal rhythms, suggesting new approaches to explore their cognitive functions and underlying circuitry.
Collapse
Affiliation(s)
- Julia Berzhanskaya
- Center for Neural Informatics, Structures, & Plasticity, and Molecular Neuroscience Department; Krasnow Institute for Advanced Study, George Mason University, Fairfax, VA, USA
| | | | | | | | | |
Collapse
|
78
|
Avella Gonzalez OJ, van Aerde KI, van Elburg RAJ, Poil SS, Mansvelder HD, Linkenkaer-Hansen K, van Pelt J, van Ooyen A. External drive to inhibitory cells induces alternating episodes of high- and low-amplitude oscillations. PLoS Comput Biol 2012; 8:e1002666. [PMID: 22956901 PMCID: PMC3431298 DOI: 10.1371/journal.pcbi.1002666] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 07/16/2012] [Indexed: 11/18/2022] Open
Abstract
Electrical oscillations in neuronal network activity are ubiquitous in the brain and have been associated with cognition and behavior. Intriguingly, the amplitude of ongoing oscillations, such as measured in EEG recordings, fluctuates irregularly, with episodes of high amplitude alternating with episodes of low amplitude. Despite the widespread occurrence of amplitude fluctuations in many frequency bands and brain regions, the mechanisms by which they are generated are poorly understood. Here, we show that irregular transitions between sub-second episodes of high- and low-amplitude oscillations in the alpha/beta frequency band occur in a generic neuronal network model consisting of interconnected inhibitory and excitatory cells that are externally driven by sustained cholinergic input and trains of action potentials that activate excitatory synapses. In the model, we identify the action potential drive onto inhibitory cells, which represents input from other brain areas and is shown to desynchronize network activity, to be crucial for the emergence of amplitude fluctuations. We show that the duration distributions of high-amplitude episodes in the model match those observed in rat prefrontal cortex for oscillations induced by the cholinergic agonist carbachol. Furthermore, the mean duration of high-amplitude episodes varies in a bell-shaped manner with carbachol concentration, just as in mouse hippocampus. Our results suggest that amplitude fluctuations are a general property of oscillatory neuronal networks that can arise through background input from areas external to the network. Rhythmic changes in electrical activity are observed throughout the brain, and arise as a result of reciprocal interactions between excitatory and inhibitory neurons. Synchronized activity of a large number of neurons gives rise to macroscopic oscillations in electrical activity, which can be measured in EEG recordings and are thought to have a key role in learning and memory. Interestingly, the amplitude of ongoing oscillations fluctuates irregularly, with high-amplitude episodes alternating with low-amplitude episodes. Although these amplitude fluctuations occur in many brain regions, the mechanisms by which they are generated are still poorly known. To get insight into potential mechanisms, we investigated whether such fluctuations occur in a computational model of a neuronal network. We show that the model generates amplitude fluctuations that are similar to those observed in experimental data and that external input from other brain areas to the inhibitory cells of the network is essential for their generation. This input can disrupt the synchrony of activity, causing transitions between episodes of high synchrony (high oscillation amplitudes) and episodes of low synchrony (low oscillation amplitudes). Episodes of high synchrony are relevant for brain function because they provide favorable conditions for learning.
Collapse
Affiliation(s)
- Oscar J. Avella Gonzalez
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam, Amsterdam, The Netherlands
| | - Karlijn I. van Aerde
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam, Amsterdam, The Netherlands
| | - Ronald A. J. van Elburg
- Institute of Artificial Intelligence, Faculty of Mathematics and Natural Sciences, University of Groningen, Bernoulliborg, Groningen, The Netherlands
| | - Simon-Shlomo Poil
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam, Amsterdam, The Netherlands
| | - Huibert D. Mansvelder
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam, Amsterdam, The Netherlands
| | - Klaus Linkenkaer-Hansen
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam, Amsterdam, The Netherlands
| | - Jaap van Pelt
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam, Amsterdam, The Netherlands
| | - Arjen van Ooyen
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam, Amsterdam, The Netherlands
- * E-mail:
| |
Collapse
|
79
|
Kowalczyk T, Konopacki J, Bocian R, Caban B. Theta-related gating cells in hippocampal formation: In vivo and in vitro study. Hippocampus 2012; 23:30-9. [DOI: 10.1002/hipo.22050] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/30/2012] [Indexed: 02/05/2023]
|
80
|
Montijn JS, Klink PC, van Wezel RJA. Divisive normalization and neuronal oscillations in a single hierarchical framework of selective visual attention. Front Neural Circuits 2012; 6:22. [PMID: 22586372 PMCID: PMC3343306 DOI: 10.3389/fncir.2012.00022] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Accepted: 04/12/2012] [Indexed: 11/13/2022] Open
Abstract
Divisive normalization models of covert attention commonly use spike rate modulations as indicators of the effect of top-down attention. In addition, an increasing number of studies have shown that top-down attention increases the synchronization of neuronal oscillations as well, particularly in gamma-band frequencies (25–100 Hz). Although modulations of spike rate and synchronous oscillations are not mutually exclusive as mechanisms of attention, there has thus far been little effort to integrate these concepts into a single framework of attention. Here, we aim to provide such a unified framework by expanding the normalization model of attention with a multi-level hierarchical structure and a time dimension; allowing the simulation of a recently reported backward progression of attentional effects along the visual cortical hierarchy. A simple cascade of normalization models simulating different cortical areas is shown to cause signal degradation and a loss of stimulus discriminability over time. To negate this degradation and ensure stable neuronal stimulus representations, we incorporate a kind of oscillatory phase entrainment into our model that has previously been proposed as the “communication-through-coherence” (CTC) hypothesis. Our analysis shows that divisive normalization and oscillation models can complement each other in a unified account of the neural mechanisms of selective visual attention. The resulting hierarchical normalization and oscillation (HNO) model reproduces several additional spatial and temporal aspects of attentional modulation and predicts a latency effect on neuronal responses as a result of cued attention.
Collapse
Affiliation(s)
- Jorrit Steven Montijn
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam Amsterdam, Netherlands
| | | | | |
Collapse
|
81
|
Kann O. The energy demand of fast neuronal network oscillations: insights from brain slice preparations. Front Pharmacol 2012; 2:90. [PMID: 22291647 PMCID: PMC3254178 DOI: 10.3389/fphar.2011.00090] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Accepted: 12/20/2011] [Indexed: 01/09/2023] Open
Abstract
Fast neuronal network oscillations in the gamma range (30-100 Hz) in the cerebral cortex have been implicated in higher cognitive functions such as sensual perception, working memory, and, perhaps, consciousness. However, little is known about the energy demand of gamma oscillations. This is mainly caused by technical limitations that are associated with simultaneous recordings of neuronal activity and energy metabolism in small neuronal networks and at the level of mitochondria in vivo. Thus recent studies have focused on brain slice preparations to address the energy demand of gamma oscillations in vitro. Here, reports will be summarized and discussed that combined electrophysiological recordings, oxygen sensor microelectrodes, and live-cell fluorescence imaging in acutely prepared slices and organotypic slice cultures of the hippocampus from both, mouse and rat. These reports consistently show that gamma oscillations can be reliably induced in hippocampal slice preparations by different pharmacological tools. They suggest that gamma oscillations are associated with high energy demand, requiring both rapid adaptation of oxidative energy metabolism and sufficient supply with oxygen and nutrients. These findings might help to explain the exceptional vulnerability of higher cognitive functions during pathological processes of the brain, such as circulatory disturbances, genetic mitochondrial diseases, and neurodegeneration.
Collapse
Affiliation(s)
- Oliver Kann
- Institute of Physiology and Pathophysiology, University of Heidelberg Heidelberg, Germany. oliver.kann@physiologie
| |
Collapse
|
82
|
Pandey AK, Kamarajan C, Rangaswamy M, Porjesz B. Event-Related Oscillations in Alcoholism Research: A Review. ACTA ACUST UNITED AC 2012; Suppl 7. [PMID: 24273686 DOI: 10.4172/2155-6105.s7-001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Alcohol dependence is characterized as a multi-factorial disorder caused by a complex interaction between genetic and environmental liabilities across development. A variety of neurocognitive deficits/dysfunctions involving impairments in different brain regions and/or neural circuitries have been associated with chronic alcoholism, as well as with a predisposition to develop alcoholism. Several neurobiological and neurobehavioral approaches and methods of analyses have been used to understand the nature of these neurocognitive impairments/deficits in alcoholism. In the present review, we have examined relatively novel methods of analyses of the brain signals that are collectively referred to as event-related oscillations (EROs) and show promise to further our understanding of human brain dynamics while performing various tasks. These new measures of dynamic brain processes have exquisite temporal resolution and allow the study of neural networks underlying responses to sensory and cognitive events, thus providing a closer link to the physiology underlying them. Here, we have reviewed EROs in the study of alcoholism, their usefulness in understanding dynamical brain functions/dysfunctions associated with alcoholism as well as their utility as effective endophenotypes to identify and understand genes associated with both brain oscillations and alcoholism.
Collapse
Affiliation(s)
- Ashwini K Pandey
- Henri Begleiter Neurodynamics Laboratory, Department of Psychiatry and Behavioral Sciences, SUNY Downstate Medical Center, Brooklyn, NY 11203, USA
| | | | | | | |
Collapse
|
83
|
Lin IH, Wu RK, Chen CM. Synchronization in a noise-driven developing neural network. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 84:051923. [PMID: 22181460 DOI: 10.1103/physreve.84.051923] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Revised: 10/19/2011] [Indexed: 05/31/2023]
Abstract
We use computer simulations to investigate the structural and dynamical properties of a developing neural network whose activity is driven by noise. Structurally, the constructed neural networks in our simulations exhibit the small-world properties that have been observed in several neural networks. The dynamical change of neuronal membrane potential is described by the Hodgkin-Huxley model, and two types of learning rules, including spike-timing-dependent plasticity (STDP) and inverse STDP, are considered to restructure the synaptic strength between neurons. Clustered synchronized firing (SF) of the network is observed when the network connectivity (number of connections/maximal connections) is about 0.75, in which the firing rate of neurons is only half of the network frequency. At the connectivity of 0.86, all neurons fire synchronously at the network frequency. The network SF frequency increases logarithmically with the culturing time of a growing network and decreases exponentially with the delay time in signal transmission. These conclusions are consistent with experimental observations. The phase diagrams of SF in a developing network are investigated for both learning rules.
Collapse
Affiliation(s)
- I-H Lin
- Department of Physics, National Taiwan Normal University, Taipei, Taiwan
| | | | | |
Collapse
|
84
|
Petrov KA, Yagodina LO, Valeeva GR, Lannik NI, Nikitashina AD, Rizvanov AA, Zobov VV, Bukharaeva EA, Reznik VS, Nikolsky EE, Vyskočil F. Different sensitivities of rat skeletal muscles and brain to novel anti-cholinesterase agents, alkylammonium derivatives of 6-methyluracil (ADEMS). Br J Pharmacol 2011; 163:732-44. [PMID: 21232040 DOI: 10.1111/j.1476-5381.2011.01211.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND AND PURPOSE The rat respiratory muscle diaphragm has markedly lower sensitivity than the locomotor muscle extensor digitorum longus (EDL) to the new acetylcholinesterase (AChE) inhibitors, alkylammonium derivatives of 6-methyluracil (ADEMS). This study evaluated several possible reasons for differing sensitivity between the diaphragm and limb muscles and between the muscles and the brain. EXPERIMENTAL APPROACH Increased amplitude and prolonged decay time of miniature endplate currents were used to assess anti-cholinesterase activity in muscles. In hippocampal slices, induction of synchronous network activity was used to follow cholinesterase inhibition. The inhibitor sensitivities of purified AChE from the EDL and brain were also estimated. KEY RESULTS The intermuscular difference in sensitivity to ADEMS is partly explained caused by a higher level of mRNA and activity of 1,3-bis[5(diethyl-o-nitrobenzylammonium)pentyl]-6-methyluracildibromide (C-547)-resistant BuChE in the diaphragm. Moreover, diaphragm AChE was more than 20 times less sensitive to C-547 than that from the EDL. Sensitivity of the EDL to C-547 dramatically decreased after treadmill exercises that increased the amount of PRiMA AChE(G4), but not ColQ AChE(A12) molecular forms. The A12 form present in muscles appeared more sensitive to C-547. The main form of AChE in brain, PRiMA AChE(G4), was apparently less sensitive because brain cholinesterase activity was almost three orders of magnitude more resistant to C-547 than that of the EDL. CONCLUSIONS AND IMPLICATIONS Our findings suggest that ADEMS compounds could be used for the selective inhibition of AChEs and as potential therapeutic tools.
Collapse
Affiliation(s)
- Konstantin A Petrov
- A.E.Arbusov Institute of Organic and Physical Chemistry, Russian Academy of Sciences, Kazan, Russia
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
85
|
Ripples make waves: binding structured activity and plasticity in hippocampal networks. Neural Plast 2011; 2011:960389. [PMID: 21961073 PMCID: PMC3180853 DOI: 10.1155/2011/960389] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Revised: 06/14/2011] [Accepted: 06/23/2011] [Indexed: 11/18/2022] Open
Abstract
Establishing novel episodic memories and stable spatial representations depends on an exquisitely choreographed, multistage process involving the online encoding and offline consolidation of sensory information, a process that is largely dependent on the hippocampus. Each step is influenced by distinct neural network states that influence the pattern of activation across cellular assemblies. In recent years, the occurrence of hippocampal sharp wave ripple (SWR) oscillations has emerged as a potentially vital network phenomenon mediating the steps between encoding and consolidation, both at a cellular and network level by promoting the rapid replay and reactivation of recent activity patterns. Such events facilitate memory formation by optimising the conditions for synaptic plasticity to occur between contingent neural elements. In this paper, we explore the ways in which SWRs and other network events can bridge the gap between spatiomnemonic processing at cellular/synaptic and network levels in the hippocampus.
Collapse
|
86
|
Siegel JA, Park BS, Raber J. Methamphetamine exposure during brain development alters the brain acetylcholine system in adolescent mice. J Neurochem 2011; 119:89-99. [PMID: 21824143 DOI: 10.1111/j.1471-4159.2011.07418.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Children exposed to methamphetamine during brain development as a result of maternal drug use have long-term hippocampus-dependent cognitive impairments, but the mechanisms underlying these impairments are not understood. The acetylcholine system plays an important role in cognitive function and potential methamphetamine-induced acetylcholine alterations may be related to methamphetamine-induced cognitive impairments. In this study, we investigated the potential long-term effects of methamphetamine exposure during hippocampal development on the acetylcholine system in adolescence mice on postnatal day 30 and in adult mice on postnatal day 90. Methamphetamine exposure increased the density of acetylcholine neurons in regions of the basal forebrain and the area occupied by acetylcholine axons in the hippocampus in adolescent female mice. In contrast, methamphetamine exposure did not affect the density of GABA cells or total neurons in the basal forebrain. Methamphetamine exposure also increased the number of muscarinic acetylcholine receptors in the hippocampus of adolescent male and female mice. Our results demonstrate for the first time that methamphetamine exposure during hippocampal development affects the acetylcholine system in adolescent mice and that these changes are more profound in females than males.
Collapse
Affiliation(s)
- Jessica A Siegel
- Department of Behavioral Neuroscience, ONPRC, Oregon Health and Science University, Portland, Oregon 97239, USA
| | | | | |
Collapse
|
87
|
Kezunovic N, Urbano FJ, Simon C, Hyde J, Smith K, Garcia-Rill E. Mechanism behind gamma band activity in the pedunculopontine nucleus. Eur J Neurosci 2011; 34:404-15. [PMID: 21722210 DOI: 10.1111/j.1460-9568.2011.07766.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The pedunculopontine nucleus (PPN), part of the reticular activating system, modulates waking and paradoxical sleep. During waking and paradoxical sleep, EEG responses are characterized by low-amplitude, high-frequency oscillatory activity in the beta-gamma band range (~20-80 Hz). We have previously reported that gamma band activity may be intrinsically generated by the membrane electroresponsiveness of PPN neurons, and that the neuronal ensemble generates different patterns of gamma activity in response to specific transmitters. This study attempted to identify the voltage-gated calcium and potassium channels involved in the rising and falling phases of gamma oscillations in PPN neurons. We found that all rat (8-14 day) PPN cell types showed gamma oscillations in the presence of TTX and synaptic blockers when membrane potential was depolarized using current ramps. PPN neurons showed gamma oscillations when voltage-clamped at holding potentials above -30 mV, suggesting that their origin may be spatially located beyond voltage-clamp control. The average frequency for all PPN cell types was 23 ± 1 Hz and this increased under carbachol (47 ± 2 Hz; anova df = 64, t = 12.5, P < 0.001). The N-type calcium channel blocker ω-conotoxin-GVIA partially reduced gamma oscillations, while the P/Q-type blocker ω-agatoxin-IVA abolished them. Both ω-CgTX and ω-Aga blocked voltage-dependent calcium currents, by 56 and 52% respectively. The delayed rectifier-like potassium channel blocker α-dendrotoxin also abolished gamma oscillations. In carbachol-induced PPN population responses, ω-agatoxin-IVA reduced higher, and ω-CgTx mostly lower, frequencies. These results suggest that voltage-dependent P/Q- and, to a lesser extent, N-type calcium channels mediate gamma oscillations in PPN.
Collapse
Affiliation(s)
- Nebojsa Kezunovic
- Center for Translational Neuroscience, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | | | | | | | | | | |
Collapse
|
88
|
Rice A, Fuglevand AJ, Laine CM, Fregosi RF. Synchronization of presynaptic input to motor units of tongue, inspiratory intercostal, and diaphragm muscles. J Neurophysiol 2011; 105:2330-6. [PMID: 21307319 DOI: 10.1152/jn.01078.2010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The respiratory central pattern generator distributes rhythmic excitatory input to phrenic, intercostal, and hypoglossal premotor neurons. The degree to which this input shapes motor neuron activity can vary across respiratory muscles and motor neuron pools. We evaluated the extent to which respiratory drive synchronizes the activation of motor unit pairs in tongue (genioglossus, hyoglossus) and chest-wall (diaphragm, external intercostals) muscles using coherence analysis. This is a frequency domain technique, which characterizes the frequency and relative strength of neural inputs that are common to each of the recorded motor units. We also examined coherence across the two tongue muscles, as our previous work shows that, despite being antagonists, they are strongly coactivated during the inspiratory phase, suggesting that excitatory input from the premotor neurons is distributed broadly throughout the hypoglossal motoneuron pool. All motor unit pairs showed highly correlated activity in the low-frequency range (1-8 Hz), reflecting the fundamental respiratory frequency and its harmonics. Coherence of motor unit pairs recorded either within or across the tongue muscles was similar, consistent with broadly distributed premotor input to the hypoglossal motoneuron pool. Interestingly, motor units from diaphragm and external intercostal muscles showed significantly higher coherence across the 10-20-Hz bandwidth than tongue-muscle units. We propose that the lower coherence in tongue-muscle motor units over this range reflects a larger constellation of presynaptic inputs, which collectively lead to a reduction in the coherence between hypoglossal motoneurons in this frequency band. This, in turn, may reflect the relative simplicity of the respiratory drive to the diaphragm and intercostal muscles, compared with the greater diversity of functions fulfilled by muscles of the tongue.
Collapse
Affiliation(s)
- Amber Rice
- Department of Physiology, The University of Arizona, Tucson, AZ 85721-0093, USA
| | | | | | | |
Collapse
|
89
|
Bocian R, Posluszny A, Kowalczyk T, Kazmierska P, Konopacki J. Gap junction modulation of hippocampal formation theta and local cell discharges in anesthetized rats. Eur J Neurosci 2011; 33:471-81. [PMID: 21226774 DOI: 10.1111/j.1460-9568.2010.07545.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Renata Bocian
- Department of Neurobiology, The University of Łódź, Rewolucji 1905 no. 66, Łódź 90-222, Poland
| | | | | | | | | |
Collapse
|
90
|
Newhall KA, Kovačič G, Kramer PR, Cai D. Cascade-induced synchrony in stochastically driven neuronal networks. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2010; 82:041903. [PMID: 21230309 DOI: 10.1103/physreve.82.041903] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2009] [Revised: 08/09/2010] [Indexed: 05/30/2023]
Abstract
Perfect spike-to-spike synchrony is studied in all-to-all coupled networks of identical excitatory, current-based, integrate-and-fire neurons with delta-impulse coupling currents and Poisson spike-train external drive. This synchrony is induced by repeated cascading "total firing events," during which all neurons fire at once. In this regime, the network exhibits nearly periodic dynamics, switching between an effectively uncoupled state and a cascade-coupled total firing state. The probability of cascading total firing events occurring in the network is computed through a combinatorial analysis conditioned upon the random time when the first neuron fires and using the probability distribution of the subthreshold membrane potentials for the remaining neurons in the network. The probability distribution of the former is found from a first-passage-time problem described by a Fokker-Planck equation, which is solved analytically via an eigenfunction expansion. The latter is found using a central limit argument via a calculation of the cumulants of a single neuronal voltage. The influence of additional physiological effects that hinder or eliminate cascade-induced synchrony are also investigated. Conditions for the validity of the approximations made in the analytical derivations are discussed and verified via direct numerical simulations.
Collapse
Affiliation(s)
- Katherine A Newhall
- Mathematical Sciences Department, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, USA
| | | | | | | |
Collapse
|
91
|
Dragomir A, Akay YM, Akay M. Modeling carbachol-induced hippocampal network synchronization using hidden Markov models. J Neural Eng 2010; 7:056012. [PMID: 20841638 DOI: 10.1088/1741-2560/7/5/056012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In this work we studied the neural state transitions undergone by the hippocampal neural network using a hidden Markov model (HMM) framework. We first employed a measure based on the Lempel-Ziv (LZ) estimator to characterize the changes in the hippocampal oscillation patterns in terms of their complexity. These oscillations correspond to different modes of hippocampal network synchronization induced by the cholinergic agonist carbachol in the CA1 region of mice hippocampus. HMMs are then used to model the dynamics of the LZ-derived complexity signals as first-order Markov chains. Consequently, the signals corresponding to our oscillation recordings can be segmented into a sequence of statistically discriminated hidden states. The segmentation is used for detecting transitions in neural synchronization modes in data recorded from wild-type and triple transgenic mice models (3xTG) of Alzheimer's disease (AD). Our data suggest that transition from low-frequency (delta range) continuous oscillation mode into high-frequency (theta range) oscillation, exhibiting repeated burst-type patterns, occurs always through a mode resembling a mixture of the two patterns, continuous with burst. The relatively random patterns of oscillation during this mode may reflect the fact that the neuronal network undergoes re-organization. Further insight into the time durations of these modes (retrieved via the HMM segmentation of the LZ-derived signals) reveals that the mixed mode lasts significantly longer (p < 10(-4)) in 3xTG AD mice. These findings, coupled with the documented cholinergic neurotransmission deficits in the 3xTG mice model, may be highly relevant for the case of AD.
Collapse
Affiliation(s)
- Andrei Dragomir
- Department of Biomedical Engineering, Cullen College of Engineering, University of Houston, Houston, TX, USA
| | | | | |
Collapse
|
92
|
Wang XJ. Neurophysiological and computational principles of cortical rhythms in cognition. Physiol Rev 2010; 90:1195-268. [PMID: 20664082 DOI: 10.1152/physrev.00035.2008] [Citation(s) in RCA: 1186] [Impact Index Per Article: 84.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Synchronous rhythms represent a core mechanism for sculpting temporal coordination of neural activity in the brain-wide network. This review focuses on oscillations in the cerebral cortex that occur during cognition, in alert behaving conditions. Over the last two decades, experimental and modeling work has made great strides in elucidating the detailed cellular and circuit basis of these rhythms, particularly gamma and theta rhythms. The underlying physiological mechanisms are diverse (ranging from resonance and pacemaker properties of single cells to multiple scenarios for population synchronization and wave propagation), but also exhibit unifying principles. A major conceptual advance was the realization that synaptic inhibition plays a fundamental role in rhythmogenesis, either in an interneuronal network or in a reciprocal excitatory-inhibitory loop. Computational functions of synchronous oscillations in cognition are still a matter of debate among systems neuroscientists, in part because the notion of regular oscillation seems to contradict the common observation that spiking discharges of individual neurons in the cortex are highly stochastic and far from being clocklike. However, recent findings have led to a framework that goes beyond the conventional theory of coupled oscillators and reconciles the apparent dichotomy between irregular single neuron activity and field potential oscillations. From this perspective, a plethora of studies will be reviewed on the involvement of long-distance neuronal coherence in cognitive functions such as multisensory integration, working memory, and selective attention. Finally, implications of abnormal neural synchronization are discussed as they relate to mental disorders like schizophrenia and autism.
Collapse
Affiliation(s)
- Xiao-Jing Wang
- Department of Neurobiology and Kavli Institute of Neuroscience, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
| |
Collapse
|
93
|
Lindsly C, Frazier CJ. Two distinct and activity-dependent mechanisms contribute to autoreceptor-mediated inhibition of GABAergic afferents to hilar mossy cells. J Physiol 2010; 588:2801-22. [PMID: 20547680 DOI: 10.1113/jphysiol.2009.184648] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
We report that bath application of 3 mum carbachol (CCh), a muscarinic acetylcholine receptor agonist, reduces evoked IPSC amplitude recorded from hilar mossy cells in the rat dentate gyrus through a presynaptic mechanism. While CCh has been shown to inhibit evoked IPSCs in other systems, this effect is intriguing in that it does not require inhibitory action of either presynaptic muscarinic receptors or presynaptic cannabinoid receptors. Previous work from our lab has shown that identical application of CCh produces an action potential-dependent increase in ambient GABA in this system; however, inhibition of evoked IPSCs produced by both 3 and 10 mum CCh is insensitive to the GABA(B) antagonist CGP52432. Therefore we hypothesized that CCh-mediated inhibition of evoked IPSCs might be produced by activity-dependent increases in ambient GABA and subsequent activation of presynaptic GABA(A) receptors. Consistent with that hypothesis, we report that CCh-mediated inhibition of evoked IPSCs appears to be well correlated with CCh-mediated facilitation of spontaneous IPSCs and that CCh does not affect GABA(B)-mediated IPSCs recorded in the presence of the GABA(A) receptor antagonist picrotoxin. Intriguingly, however, we found that bath application of the GAT-1 transport blocker NO-711 (1 mum) produces inhibition of evoked IPSCs that is reversed by CGP52432, and that lower doses of CCh produce inhibition with greater CGP52432 sensitivity. These observations, combined with subsequent work on multiple pulse depression, reveal that feedback inhibition of GABAergic afferents to hilar mossy cells is governed by a complex relationship between two distinct and activity-dependent mechanisms.
Collapse
Affiliation(s)
- Casie Lindsly
- Department of Neuroscience, College of Medicine, University of Florida,1600 S.W. Archer Road, Gainesville, FL 32610, USA
| | | |
Collapse
|
94
|
Simon C, Kezunovic N, Ye M, Hyde J, Hayar A, Williams DK, Garcia-Rill E. Gamma band unit activity and population responses in the pedunculopontine nucleus. J Neurophysiol 2010; 104:463-74. [PMID: 20463196 DOI: 10.1152/jn.00242.2010] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The pedunculopontine nucleus (PPN) is involved in the activated states of waking and paradoxical sleep, forming part of the reticular activating system (RAS). The studies described tested the hypothesis that single unit and/or population responses of PPN neurons are capable of generating gamma band frequency activity. Whole cell patch clamp recordings (immersion chamber) and population responses (interface chamber) were conducted on 9- to 20-day-old rat brain stem slices. Regardless of cell type (I, II, or III) or type of response to the nonselective cholinergic receptor agonist carbachol (excitation, inhibition, biphasic), almost all PPN neurons fired at gamma band frequency, but no higher, when subjected to depolarizing steps (50 +/- 2 Hz, mean +/- SE). Nonaccommodating neurons fired at 18-100 Hz throughout depolarizing steps, while most accommodating neurons exhibited gamma band frequency of action potentials followed by gamma band membrane oscillations. These oscillations were blocked by the sodium channel blocker tetrodotoxin (TTX), suggesting that at least some are mediated by sodium currents. Population responses in the PPN showed that carbachol induced peaks of activation in the theta and gamma range, while glutamatergic receptor agonists induced overall increases in activity at theta and gamma frequencies, although in differing patterns. Gamma band activity appears to be a part of the intrinsic membrane properties of PPN neurons, and the population as a whole generates different patterns of gamma band activity under the influence of specific transmitters. Given sufficient excitation, the PPN may impart gamma band activation on its targets.
Collapse
Affiliation(s)
- Christen Simon
- Center for Translational Neuroscience, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA
| | | | | | | | | | | | | |
Collapse
|
95
|
Ye M, Hayar A, Strotman B, Garcia-Rill E. Cholinergic modulation of fast inhibitory and excitatory transmission to pedunculopontine thalamic projecting neurons. J Neurophysiol 2010; 103:2417-32. [PMID: 20181729 PMCID: PMC2867582 DOI: 10.1152/jn.01143.2009] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2009] [Accepted: 02/21/2010] [Indexed: 11/22/2022] Open
Abstract
The pedunculopontine nucleus (PPN) is part of the cholinergic arm of the reticular activating system, which is mostly active during waking and rapid-eye movement sleep. The PPN projects to the thalamus and receives cholinergic inputs from the laterodorsal tegmental nucleus and contralateral PPN. We employed retrograde labeling and whole cell recordings to determine the modulation of GABAergic, glycinergic, and glutamatergic transmission to PPN thalamic projecting neurons, and their postsynaptic responses to the nonspecific cholinergic agonist carbachol. M2 and M4 muscarinic receptor-modulated inhibitory postsynaptic responses were observed in 73% of PPN output neurons; in 12.9%, M1 and nicotinic receptor-mediated excitation was detected; and muscarinic and nicotinic-modulated fast inhibitory followed by slow excitatory biphasic responses were evident in 6.7% of cells. A significant increase in the frequency of spontaneous excitatory postsynaptic currents (EPSCs) and inhibitory postsynaptic currents during carbachol application was observed in 66.2% and 65.2% of efferent neurons, respectively. This effect was blocked by a M1 antagonist or nonselective muscarinic blocker, indicating that glutamatergic, GABAergic, and/or glycinergic neurons projecting to PPN output neurons are excited through muscarinic receptors. Decreases in the frequency of miniature EPSCs, and amplitude of electrical stimulation-evoked EPSCs, were blocked by a M2 antagonist, suggesting the presence of M2Rs at terminals of presynaptic glutamatergic neurons. Carbachol-induced multiple types of postsynaptic responses, enhancing both inhibitory and excitatory fast transmission to PPN thalamic projecting neurons through muscarinic receptors. These results provide possible implications for the generation of different frequency oscillations in PPN thalamic projecting neurons during distinct sleep-wake states.
Collapse
Affiliation(s)
- Meijun Ye
- Center for Translational Neuroscience, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | | | | | | |
Collapse
|
96
|
Cappaert NLM, Lopes da Silva FH, Wadman WJ. Spatio-temporal dynamics of theta oscillations in hippocampal-entorhinal slices. Hippocampus 2010; 19:1065-77. [PMID: 19338021 DOI: 10.1002/hipo.20570] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Theta oscillations (4-12 Hz) are associated with learning and memory and are found in the hippocampus and the entorhinal cortex (EC). The spatio-temporal organization of rhythmic activity in the hippocampal-EC complex was investigated in vitro. The voltage sensitive absorption dye NK3630 was used to record the changes in aggregated membrane voltage simultaneously from the neuronal networks involved. Oscillatory activity at 7.0 Hz (range, 5.8-8.2) was induced in the slice with the muscarinic agonist carbachol (75-100 microM) in the presence of bicuculline (5 microM). Time relations between all recording sites were analyzed using cross-correlation functions which revealed systematic phase shifts in the theta oscillation recorded from the different entorhinal and hippocampal subregions. These phase shifts could be interpreted as propagation delays. The oscillation propagates over the slice in a characteristic spatio-temporal sequence, where the entorhinal cortex leads, followed by the subiculum and then the dentate gyrus (DG), to finally reach the CA3 and the CA1 area. The delay from dentate gyrus to the CA3 area was 12.4 +/- 1.1 ms (mean +/- s.e.m.) and from the CA3 to the CA1 region it was 10.9 +/- 1.9 ms. The propagation delays between the hippocampal subregions resemble the latencies of electrically evoked responses in the same subregions. Removing the entorhinal cortex from the slice changed the spatiotemporal pattern into a more clustered pattern with higher local synchrony. We conclude that in the slice, carbachol-induced theta oscillations are initiated in the entorhinal cortex. The EC could serve to control the information flow through the neuronal network in the subregions of the hippocampus by synchronizing and/or entraining their responses to external inputs.
Collapse
Affiliation(s)
- N L M Cappaert
- SILS - Center for NeuroScience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands.
| | | | | |
Collapse
|
97
|
Intracranial EEG correlates of expectancy and memory formation in the human hippocampus and nucleus accumbens. Neuron 2010; 65:541-9. [PMID: 20188658 DOI: 10.1016/j.neuron.2010.02.006] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/08/2010] [Indexed: 11/29/2022]
Abstract
The human brain is adept at anticipating upcoming events, but in a rapidly changing world, it is essential to detect and encode events that violate these expectancies. Unexpected events are more likely to be remembered than predictable events, but the underlying neural mechanisms for these effects remain unclear. We report intracranial EEG recordings from the hippocampus of epilepsy patients, and from the nucleus accumbens of depression patients. We found that unexpected stimuli enhance an early (187 ms) and a late (482 ms) hippocampal potential, and that the late potential is associated with successful memory encoding for these stimuli. Recordings from the nucleus accumbens revealed a late potential (peak at 475 ms), which increases in magnitude during unexpected items, but no subsequent memory effect and no early component. These results are consistent with the hypothesis that activity in a loop involving the hippocampus and the nucleus accumbens promotes encoding of unexpected events.
Collapse
|
98
|
Cell type-specific control of neuronal responsiveness by gamma-band oscillatory inhibition. J Neurosci 2010; 30:2150-9. [PMID: 20147542 DOI: 10.1523/jneurosci.4818-09.2010] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Neocortical networks are composed of diverse populations of cells that differ in their chemical content, electrophysiological characteristics, and connectivity. Gamma-frequency oscillatory activity of inhibitory subnetworks has been hypothesized to regulate information processing in the cortex as a whole. Inhibitory neurons in these subnetworks synchronize their firing and selectively innervate the perisomatic compartments of their target neurons, generating both tonic and rapidly fluctuating inhibition. How do different types of cortical neurons respond to changes in the level and structure of perisomatic inhibition? What accounts for response heterogeneity between cell types, and are these response properties fixed or flexible? To answer these questions, we use in vitro whole-cell recording and dynamic-clamp somatic current injection to study six distinct types of cortical neurons. We demonstrate that different types of neurons systematically vary in their receptiveness to fast changes in the structure of inhibition and the range over which changes in inhibitory tone affect their output. Using simple neuron models and model neuron hybrids (dynamic clamp), we determine which intrinsic differences between cell types lead to these variations in receptiveness. These results suggest important differences in the way cell types are affected by gamma-frequency inhibition, which may have important circuit level implications. Although intrinsic differences observed in vitro are useful for the elucidation of basic cellular properties and differences between cell types, we also investigate how the integrative properties of neurons are likely to be rapidly modulated in the context of active networks in vivo.
Collapse
|
99
|
Onton J, Makeig S. High-frequency Broadband Modulations of Electroencephalographic Spectra. Front Hum Neurosci 2009; 3:61. [PMID: 20076775 PMCID: PMC2806183 DOI: 10.3389/neuro.09.061.2009] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Accepted: 11/18/2009] [Indexed: 11/15/2022] Open
Abstract
High-frequency cortical potentials in electroencephalographic (EEG) scalp recordings have low amplitudes and may be confounded with scalp muscle activities. EEG data from an eyes-closed emotion imagination task were linearly decomposed using independent component analysis (ICA) into maximally independent component (IC) processes. Joint decomposition of IC log spectrograms into source- and frequency-independent modulator (IM) processes revealed three distinct classes of IMs that separately modulated broadband high-frequency (∼15–200 Hz) power of brain, scalp muscle, and likely ocular motor IC processes. Multi-dimensional scaling revealed significant but spatially complex relationships between mean broadband brain IM effects and the valence of the imagined emotions. Thus, contrary to prevalent assumption, unitary modes of spectral modulation of frequencies encompassing the beta, gamma, and high gamma frequency ranges can be isolated from scalp-recorded EEG data and may be differentially associated with brain sources and cognitive activities.
Collapse
Affiliation(s)
- Julie Onton
- Institute for Neural Computation, University of California San Diego, La Jolla, CA, USA
| | | |
Collapse
|
100
|
Kowalczyk T, Gołębiewski H, Konopacki J. Is the dentate gyrus an independent generator of in vitro recorded theta rhythm? Brain Res Bull 2009; 80:139-46. [PMID: 19615430 DOI: 10.1016/j.brainresbull.2009.07.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Revised: 06/25/2009] [Accepted: 07/04/2009] [Indexed: 10/20/2022]
|