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Kumagai S, Shiramatsu TI, Matsumura A, Ishishita Y, Ibayashi K, Onuki Y, Kawai K, Takahashi H. Frequency-specific modulation of oscillatory activity in the rat auditory cortex by vagus nerve stimulation. Brain Stimul 2023; 16:1476-1485. [PMID: 37777110 DOI: 10.1016/j.brs.2023.09.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 09/21/2023] [Accepted: 09/21/2023] [Indexed: 10/02/2023] Open
Abstract
BACKGROUND We previously found that vagus nerve stimulation (VNS) strengthened stimulus-evoked activity in the superficial layer of the sensory cortex but not in the deep layer, suggesting that VNS altered the balance between the feedforward (FF) and feedback (FB) pathways. Band-specific oscillatory activities in the cortex could serve as an index of the FF-FB balance, but whether VNS affects cortical oscillations along sensory pathways through neuromodulators remains unclear. HYPOTHESIS VNS modulates the FF-FB balance through the cholinergic and noradrenergic systems, which modulate stimulus gain in the cortex. METHODS We investigated the effects of VNS using electrocorticography in the auditory cortex of 34 Wistar rats under general anesthesia while presenting click stimuli. In the time-frequency analyses, the putative modulation of the FF and FB pathways was estimated using high- and low-frequency power. We assessed, using analysis of variance, how VNS modulates auditory-evoked activities and how the modulation changes with cholinergic and noradrenergic antagonists. RESULTS VNS increased auditory cortical evoked potentials, consistent with results of our previous work. Furthermore, VNS increased auditory-evoked gamma and beta powers and decreased theta power. Local administration of cholinergic antagonists in the auditory cortex selectively disrupted the VNS-induced increase in gamma and beta power, while noradrenergic antagonists disrupted the decrease in theta power. CONCLUSIONS VNS might strengthen the FF pathway through the cholinergic system and attenuate the FB pathway through the noradrenergic system in the auditory cortex. Cortical gain modulation through the VNS-induced neuromodulatory system provides new mechanistic insights into the effect of VNS on auditory processing.
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Affiliation(s)
- Shinichi Kumagai
- Department of Neurosurgery, Jichi Medical University, Tochigi, Japan; Department of Mechano-Informatics, Graduate School of Information Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Tomoyo Isoguchi Shiramatsu
- Department of Mechano-Informatics, Graduate School of Information Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Akane Matsumura
- Department of Mechano-Informatics, Graduate School of Information Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Yohei Ishishita
- Department of Neurosurgery, Jichi Medical University, Tochigi, Japan
| | - Kenji Ibayashi
- Department of Neurosurgery, Jichi Medical University, Tochigi, Japan
| | - Yoshiyuki Onuki
- Department of Neurosurgery, Jichi Medical University, Tochigi, Japan
| | - Kensuke Kawai
- Department of Neurosurgery, Jichi Medical University, Tochigi, Japan
| | - Hirokazu Takahashi
- Department of Mechano-Informatics, Graduate School of Information Science and Technology, The University of Tokyo, Tokyo, Japan.
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Kunnath AJ, Gifford RH, Wallace MT. Cholinergic modulation of sensory perception and plasticity. Neurosci Biobehav Rev 2023; 152:105323. [PMID: 37467908 PMCID: PMC10424559 DOI: 10.1016/j.neubiorev.2023.105323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 07/07/2023] [Accepted: 07/13/2023] [Indexed: 07/21/2023]
Abstract
Sensory systems are highly plastic, but the mechanisms of sensory plasticity remain unclear. People with vision or hearing loss demonstrate significant neural network reorganization that promotes adaptive changes in other sensory modalities as well as in their ability to combine information across the different senses (i.e., multisensory integration. Furthermore, sensory network remodeling is necessary for sensory restoration after a period of sensory deprivation. Acetylcholine is a powerful regulator of sensory plasticity, and studies suggest that cholinergic medications may improve visual and auditory abilities by facilitating sensory network plasticity. There are currently no approved therapeutics for sensory loss that target neuroplasticity. This review explores the systems-level effects of cholinergic signaling on human visual and auditory perception, with a focus on functional performance, sensory disorders, and neural activity. Understanding the role of acetylcholine in sensory plasticity will be essential for developing targeted treatments for sensory restoration.
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Affiliation(s)
- Ansley J Kunnath
- Neuroscience Graduate Program, Vanderbilt University, Nashville, TN, USA; Medical Scientist Training Program, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - René H Gifford
- Department of Otolaryngology, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Hearing and Speech Sciences, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Mark T Wallace
- Department of Hearing and Speech Sciences, Vanderbilt University School of Medicine, Nashville, TN, USA; Department of Psychology, Vanderbilt University, Nashville, TN, USA; Department of Pharmacology, Vanderbilt University, Nashville, TN, USA; Department of Psychiatry and Behavioral Sciences, Vanderbilt University, Nashville, TN, USA.
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Li Q, Song JL, Li SH, Westover MB, Zhang R. Effects of Cholinergic Neuromodulation on Thalamocortical Rhythms During NREM Sleep: A Model Study. Front Comput Neurosci 2020; 13:100. [PMID: 32038215 PMCID: PMC6990259 DOI: 10.3389/fncom.2019.00100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 12/30/2019] [Indexed: 11/13/2022] Open
Abstract
It has been suggested that cholinergic neurons shape the oscillatory activity of the thalamocortical (TC) network in behavioral and electrophysiological experiments. However, theoretical modeling demonstrating how cholinergic neuromodulation of thalamocortical rhythms during non-rapid eye movement (NREM) sleep might occur has been lacking. In this paper, we first develop a novel computational model (TC-ACH) by incorporating a cholinergic neuron population (CH) into the classical thalamo-cortical circuitry, where connections between populations are modeled in accordance with existing knowledge. The neurotransmitter acetylcholine (ACH) released by neurons in CH, which is able to change the discharge activity of thalamocortical neurons, is the primary focus of our work. Simulation results with our TC-ACH model reveal that the cholinergic projection activity is a key factor in modulating oscillation patterns in three ways: (1) transitions between different patterns of thalamocortical oscillations are dramatically modulated through diverse projection pathways; (2) the model expresses a stable spindle oscillation state with certain parameter settings for the cholinergic projection from CH to thalamus, and more spindles appear when the strength of cholinergic input from CH to thalamocortical neurons increases; (3) the duration of oscillation patterns during NREM sleep including K-complexes, spindles, and slow oscillations is longer when cholinergic input from CH to thalamocortical neurons becomes stronger. Our modeling results provide insights into the mechanisms by which the sleep state is controlled, and provide a theoretical basis for future experimental and clinical studies.
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Affiliation(s)
- Qiang Li
- Medical Big Data Research Center, Northwest University, Xi'an, China
- Department of Neurology, Massachusetts General Hospital, Boston, MA, United States
| | - Jiang-Ling Song
- Medical Big Data Research Center, Northwest University, Xi'an, China
- Department of Neurology, Massachusetts General Hospital, Boston, MA, United States
| | - Si-Hui Li
- Medical Big Data Research Center, Northwest University, Xi'an, China
| | - M. Brandon Westover
- Department of Neurology, Massachusetts General Hospital, Boston, MA, United States
| | - Rui Zhang
- Medical Big Data Research Center, Northwest University, Xi'an, China
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4
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Durhan G, Diker S, Has AC, Karakaya J, Kurne AT, Karabudak R, Oguz KK. Assessment of the effect of cigarette smoking on regional brain volumes and lesion load in patients with clinically isolated syndrome. Int J Neurosci 2015; 126:805-811. [DOI: 10.3109/00207454.2015.1073727] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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5
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Bueno-Junior LS, Lopes-Aguiar C, Ruggiero RN, Romcy-Pereira RN, Leite JP. Muscarinic and nicotinic modulation of thalamo-prefrontal cortex synaptic plasticity [corrected] in vivo. PLoS One 2012; 7:e47484. [PMID: 23118873 PMCID: PMC3484139 DOI: 10.1371/journal.pone.0047484] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Accepted: 09/11/2012] [Indexed: 02/06/2023] Open
Abstract
The mediodorsal nucleus of the thalamus (MD) is a rich source of afferents to the medial prefrontal cortex (mPFC). Dysfunctions in the thalamo-prefrontal connections can impair networks implicated in working memory, some of which are affected in Alzheimer disease and schizophrenia. Considering the importance of the cholinergic system to cortical functioning, our study aimed to investigate the effects of global cholinergic activation of the brain on MD-mPFC synaptic plasticity by measuring the dynamics of long-term potentiation (LTP) and depression (LTD) in vivo. Therefore, rats received intraventricular injections either of the muscarinic agonist pilocarpine (PILO; 40 nmol/µL), the nicotinic agonist nicotine (NIC; 320 nmol/µL), or vehicle. The injections were administered prior to either thalamic high-frequency (HFS) or low-frequency stimulation (LFS). Test pulses were applied to MD for 30 min during baseline and 240 min after HFS or LFS, while field postsynaptic potentials were recorded in the mPFC. The transient oscillatory effects of PILO and NIC were monitored through recording of thalamic and cortical local field potentials. Our results show that HFS did not affect mPFC responses in vehicle-injected rats, but induced a delayed-onset LTP with distinct effects when applied following PILO or NIC. Conversely, LFS induced a stable LTD in control subjects, but was unable to induce LTD when applied after PILO or NIC. Taken together, our findings show distinct modulatory effects of each cholinergic brain activation on MD-mPFC plasticity following HFS and LFS. The LTP-inducing action and long-lasting suppression of cortical LTD induced by PILO and NIC might implicate differential modulation of thalamo-prefrontal functions under low and high input drive.
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Affiliation(s)
- Lezio Soares Bueno-Junior
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Cleiton Lopes-Aguiar
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Rafael Naime Ruggiero
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Rodrigo Neves Romcy-Pereira
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
- Brain Institute, Federal University of Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil
- * E-mail:
| | - João Pereira Leite
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
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6
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Abstract
Adolescent smoking is associated with auditory-cognitive deficits and structural alterations to auditory thalamocortical systems, suggesting that higher auditory function is vulnerable to nicotine exposure during adolescence. Although nicotinic acetylcholine receptors (nAChRs) regulate thalamocortical processing in adults, it is not known whether they regulate processing at earlier ages since their expression pattern changes throughout postnatal development. Here we investigate nicotinic regulation of tone-evoked current source density (CSD) profiles in mouse primary auditory cortex from just after hearing onset until adulthood. At the youngest ages, systemic nicotine did not affect CSD profiles. However, beginning in early adolescence nicotine enhanced characteristic frequency (CF)-evoked responses in layers 2-4 by enhancing thalamocortical, early intracortical, and late intracortical response components. Nicotinic responsiveness developed rapidly and peaked over the course of adolescence, then declined thereafter. Generally, responsiveness in females developed more quickly, peaked earlier, and declined more abruptly and fully than in males. In contrast to the enhancement of CF-evoked responses, nicotine suppressed shorter-latency intracortical responses to spectrally distant (non-CF) stimuli while enhancing longer-latency responses. Intracortical infusion of nAChR antagonists showed that enhancement of CF-evoked intracortical processing involves α4β2*, but not α7, nAChRs, whereas both receptor subtypes regulate non-CF-evoked late intracortical responses. Notably, antagonist effects in females implied regulation by endogenous acetylcholine. Thus, nicotinic regulation of cortical processing varies with age and sex, with peak effects during adolescence that may contribute to the vulnerability of adolescents to smoking.
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7
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Debski EA. Smoking, nicotine and visual plasticity: does what you know, tell you what you can see? Brain Res Bull 2011; 77:221-6. [PMID: 18789378 DOI: 10.1016/j.brainresbull.2008.08.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Revised: 07/24/2008] [Accepted: 08/07/2008] [Indexed: 11/29/2022]
Abstract
Nicotine exposure alters activity-dependent synaptic plasticity processes. Effects on learning and memory outcomes, and the synaptic changes that underlie them, are well-documented. Parallels in hippocampal and visual system pharmacology suggest that nicotine has the potential to alter activity-dependent structural organization in visual areas. Such alterations may contribute to deficits in visual performance reported in smoking exposed individuals.
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Affiliation(s)
- Elizabeth A Debski
- Department of Biology, University of Kentucky, 101 TH Morgan Building, Lexington, KY 40506-0225, United States.
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8
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Metherate R. Functional connectivity and cholinergic modulation in auditory cortex. Neurosci Biobehav Rev 2010; 35:2058-63. [PMID: 21144860 DOI: 10.1016/j.neubiorev.2010.11.010] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2010] [Revised: 11/08/2010] [Accepted: 11/26/2010] [Indexed: 11/26/2022]
Abstract
Although it is known that primary auditory cortex (A1) contributes to the processing and perception of sound, its precise functions and the underlying mechanisms are not well understood. Recent studies point to a remarkably broad spectral range of largely subthreshold inputs to individual neurons in A1--seemingly encompassing, in some cases, the entire audible spectrum--as evidence for potential, and potentially unique, cortical functions. We have proposed a general mechanism for spectral integration by which information converges on neurons in A1 via a combination of thalamocortical pathways and intracortical long-distance, "horizontal", pathways. Here, this proposal is briefly reviewed and updated with results from multiple laboratories. Since spectral integration in A1 is dynamically regulated, we also show how one regulatory mechanism--modulation by the neurotransmitter acetylcholine (ACh)--could act within the hypothesized framework to alter integration in single neurons. The results of these studies promote a cellular understanding of information processing in A1.
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Affiliation(s)
- Raju Metherate
- Department of Neurobiology and Behavior, Center for Hearing Research, University of California-Irvine, CA 92697-4550, United States.
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9
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Shideler KK, Yan J. M1 muscarinic receptor for the development of auditory cortical function. Mol Brain 2010; 3:29. [PMID: 20964868 PMCID: PMC2972260 DOI: 10.1186/1756-6606-3-29] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Accepted: 10/22/2010] [Indexed: 02/02/2023] Open
Abstract
The sensory cortex is subject to continuous remodelling during early development and throughout adulthood. This process is important for establishing normal brain function and is dependent on cholinergic modulation via muscarinic receptors. Five muscarinic receptor genes encode five unique receptor subtypes (M1-5). The distributions and functions of each subtype vary in central and peripheral systems. In the brain, the M1 receptor is most abundant in the cerebral cortex, where its immunoreactivity peaks transiently during early development. This likely signifies the importance of M1 receptor in the development and maintenance of normal cortical function. Several lines of study have outlined the roles of M1 receptors in the development and plasticity of the auditory cortex. For example, M1-knockout reduces experience-dependent plasticity and disrupts tonotopic mapping in the adult mouse auditory cortex. Further evidence demonstrates a role for M1 in neurite outgrowth and hence determining the structure of cortical neurons. The disruption of tonotopic maps in M1-knockout mice may be linked to alterations in thalamocortical connectivity, because the targets of thalamocortical afferents (layer IV cortical neurons) appear less mature in M1 knockouts. Herein we review the literature to date concerning M1 receptors in the auditory cortex and consider some future directions that will contribute to our understanding.
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Affiliation(s)
- Karalee K Shideler
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
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10
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Poorthuis RB, Goriounova NA, Couey JJ, Mansvelder HD. Nicotinic actions on neuronal networks for cognition: general principles and long-term consequences. Biochem Pharmacol 2009; 78:668-76. [PMID: 19426718 DOI: 10.1016/j.bcp.2009.04.031] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Accepted: 04/27/2009] [Indexed: 02/04/2023]
Abstract
Nicotine enhances cognitive performance in humans and laboratory animals. The immediate positive actions of nicotine on learning, memory and attention are well-documented. Several brain areas involved in cognition, such as the prefrontal cortex, have been implicated. Besides acute effects on these brain areas and on brain function, a picture is emerging showing that long-term consequences of nicotine exposure during adolescence can be detrimental for cognitive performance. The majority of adult smokers started the habit during adolescence. Our knowledge on the types of nicotinic receptors in the brain areas that are candidates for mediating nicotine's effects is increasing. However, much less is known about the underlying cellular mechanisms. A series of recent studies have uncovered exciting features of the mechanisms by which nicotine alters prefrontal cortex neuronal activity, synaptic plasticity, gene expression and cognitive function, and how these changes may have a lasting effect on the developing brain. In this review, we discuss these exciting findings and identify several common principles by which nicotinic receptor activation modulates cortical circuits involved in cognition. Understanding how nicotine induces long-term changes in neuronal circuits and alters plasticity in the prefrontal cortex is essential to determining how these mechanisms interact to alter cognition.
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Affiliation(s)
- Rogier B Poorthuis
- Department of Integrative Neurophysiology, CNCR, Neuroscience Campus Amsterdam, VU University, De Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands
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11
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Azizian A, Monterosso J, O'Neill J, London ED. Magnetic resonance imaging studies of cigarette smoking. Handb Exp Pharmacol 2009:113-43. [PMID: 19184648 DOI: 10.1007/978-3-540-69248-5_5] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This chapter reviews studies that have applied magnetic resonance imaging (MRI) toward a better understanding of the neurobiological correlates and consequences of cigarette smoking and nicotine dependence. The findings demonstrate that smokers differ from nonsmokers in regional brain structure and neurochemistry, as well as in activation in response to smoking-related stimuli and during the execution of cognitive tasks. We also review functional neuroimaging studies on the effects of nicotine administration on brain activity, both at rest and during the execution of cognitive tasks, independent of issues related to nicotine withdrawal and craving. Although chronic cigarette smoking is associated with poor cognitive performance, acute nicotine administration appears to enhance cognitive performance and increase neural efficiency in smokers.
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Affiliation(s)
- Allen Azizian
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA, USA
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12
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Abstract
While most cigarette smokers endorse a desire to quit smoking, only 14-49% will achieve abstinence after 6 months or more of treatment. A greater understanding of the effects of smoking on brain function may result in improved pharmacological and behavioral interventions for this condition. Research groups have examined the effects of acute and chronic nicotine/cigarette exposure on brain activity using functional imaging; the purpose of this chapter is to synthesize findings from such studies and present a coherent model of brain function in smokers. Responses to acute administration of nicotine/smoking include reduced global brain activity; activation of the prefrontal cortex, thalamus, and visual system; activation of the thalamus and visual cortex during visual cognitive tasks; and increased dopamine (DA) concentration in the ventral striatum/nucleus accumbens. Responses to chronic nicotine/cigarette exposure include decreased monoamine oxidase (MAO) A and B activity in the basal ganglia and a reduction in alpha4beta2 nicotinic acetylcholine receptor (nAChR) availability in the thalamus and putamen (accompanied by an overall upregulation of these receptors). These findings indicate that smoking enhances neurotransmission through cortico-basal ganglia-thalamic circuits by direct stimulation of nAChRs, indirect stimulation via DA release or MAO inhibition, or a combination of these and possibly other factors. Activation of this circuitry may be responsible for the effects of smoking seen in tobacco-dependent smokers, such as improvements in attentional performance, mood, anxiety, and irritability.
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Affiliation(s)
- Anil Sharma
- Department of Psychiatry and Biobehavioral Sciences, UCLA School of Medicine, Greater Los Angeles VA Healthcare System, 11301 Wilshire Blvd. Bldg 256 Suite 221, Los Angeles, CA 90073, USA.
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Mansvelder HD, Mertz M, Role LW. Nicotinic modulation of synaptic transmission and plasticity in cortico-limbic circuits. Semin Cell Dev Biol 2009; 20:432-40. [PMID: 19560048 DOI: 10.1016/j.semcdb.2009.01.007] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Revised: 01/11/2009] [Accepted: 01/13/2009] [Indexed: 11/19/2022]
Abstract
Nicotine is the principle addictive agent delivered via cigarette smoking. The addictive activity of nicotine is due to potent interactions with nicotinic acetylcholine receptors (nAChRs) on neurons in the reinforcement and reward circuits of the brain. Beyond its addictive actions, nicotine is thought to have positive effects on performance in working memory and short-term attention-related tasks. The brain areas involved in such behaviors are part of an extensive cortico-limbic network that includes relays between prefrontal cortex (PFC) and cingulate cortex (CC), hippocampus, amygdala, ventral tegmental area (VTA) and the nucleus accumbens (nAcc). Nicotine activates a broad array of nAChRs subtypes that can be targeted to pre- as well as peri- and post-synaptic locations in these areas. Thereby, nicotine not only excites different types of neurons, but it also perturbs baseline neuronal communication, alters synaptic properties and modulates synaptic plasticity. In this review we focus on recent findings on nicotinic modulation of cortical circuits and their targets fields, which show that acute and transient activation of nicotinic receptors in cortico-limbic circuits triggers a series of events that affects cognitive performance in a long lasting manner. Understanding how nicotine induces long-term changes in synapses and alters plasticity in the cortico-limbic circuits is essential to determining how these areas interact in decoding fundamental aspects of cognition and reward.
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Affiliation(s)
- Huibert D Mansvelder
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research (CNCR), VU University Amsterdam, Amsterdam, The Netherlands.
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CLEARWATER JM, KERR CC, RENNIE CJ, ROBINSON PA. NEURAL MECHANISMS OF ERP CHANGE: COMBINING INSIGHTS FROM ELECTROPHYSIOLOGY AND MATHEMATICAL MODELING. J Integr Neurosci 2008; 7:529-50. [DOI: 10.1142/s0219635208002003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2008] [Revised: 11/10/2008] [Indexed: 11/18/2022] Open
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Clearwater JM, Rennie CJ, Robinson PA. Mean field model of acetylcholine mediated dynamics in the thalamocortical system. J Theor Biol 2008; 255:287-98. [PMID: 18775441 DOI: 10.1016/j.jtbi.2008.08.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2008] [Revised: 07/01/2008] [Accepted: 08/08/2008] [Indexed: 12/31/2022]
Abstract
A recent continuum model of the large scale electrical activity of the thalamocortical system is generalized to include cholinergic modulation. The model is examined analytically and numerically to determine the effect of acetylcholine (ACh) on its steady states, linear stability, spectrum, and temporal responses. Changing the ACh concentration moves the system between zones of one, three, and five steady states, showing that neuromodulation of synaptic strength is a possible mechanism by which multiple steady states emerge in the brain. The lowest firing rate steady state is always stable, and subsequent fixed points alternate between stable and unstable. Increasing ACh concentration changes the form of the spectrum. Increasing the tonic level of ACh concentration increases the magnitudes of the N100 and P200 in the evoked response potential (ERP), without changing the timing of these peaks. Driving the system with a pulse of cholinergic activity results in a transient increase in the firing rate of cortical neurons that lasts over 10s. Step-like increases in cortical ACh concentration cause increases in the firing rate of cortical neurons, with rapid responses due to fast acting nicotinic receptors and slower responses due to muscarinic receptor suppression of intracortical connections.
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Affiliation(s)
- J M Clearwater
- School of Physics, University of Sydney, New South Wales 2006, Australia.
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Liang K, Poytress BS, Weinberger NM, Metherate R. Nicotinic modulation of tone-evoked responses in auditory cortex reflects the strength of prior auditory learning. Neurobiol Learn Mem 2008; 90:138-46. [PMID: 18378471 PMCID: PMC2464281 DOI: 10.1016/j.nlm.2008.02.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2008] [Revised: 02/19/2008] [Accepted: 02/20/2008] [Indexed: 11/25/2022]
Abstract
Nicotinic acetylcholine receptors (nAChRs) contribute to sensory-cognitive function, as demonstrated by evidence that nAChR activation enhances, and nAChR blockade impairs, neural processing of sensory stimuli and sensory-cognitive behavior. To better understand the relationship between nAChR function and behavior, here we compare the strength of nAChR-mediated physiology in individual animals to their prior auditory behavioral performance. Adult rats were trained on an auditory-cued, active avoidance task over 4 days and classified as "good," "intermediate" or "poor" performers based on their initial rate of learning and eventual level of performance. Animals were then anesthetized, and tone-evoked local field potentials (LFPs) recorded in layer 4 of auditory cortex (ACx) before and after a test dose of nicotine (0.7mg/kg, s.c.) or saline. In "good" performers, nicotine enhanced LFP amplitude and decreased response threshold to characteristic frequency (CF) stimuli, yet had opposite effects (decreased amplitude, increased threshold) on responses to spectrally distant stimuli; i.e., cortical receptive fields became more selective for CF stimuli. In contrast, nicotine had little effect on LFP amplitude in "intermediate" or "poor" performing animals. Nicotine did, however, reduce LFP onset latency in all three groups, indicating that all received an effective dose of the drug. Our findings suggest that nicotinic regulation of cortical receptive fields may be a distinguishing feature of the best-performing animals, and may facilitate sensory-related learning by enhancing receptive field selectivity.
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Affiliation(s)
- Kevin Liang
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, Center for Hearing Research, University of California, Irvine, CA 92697, USA
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Abstract
Central thalamus has extensive connections with basal ganglia and frontal cortex that are thought to play a critical role in sensory-guided goal-directed behavior. Central thalamic activity is influenced by cholinergic projections from mesopontine nuclei. To elucidate this function we trained rats to respond to lights in a reaction time (RT) task and compared effects of muscarinic (2.4, 7.3, 22 nmol scopolamine) and nicotinic (5.4, 16, 49, 98 nmol mecamylamine) antagonists with the GABA(A) agonist muscimol (0.1, 0.3, 1.0 nmol) in central thalamus. We compared this with subcutaneous (systemic) effects of mecamylamine (3.2, 9.7, 29 micromol/kg) and scopolamine (0.03, 0.09, 0.26 micromol/kg). Subcutaneous scopolamine increased omissions (failure to respond within a 3-s response window) at the highest dose tested. Subcutaneous mecamylamine increased omissions at the highest dose tested while impairing RT and per cent correct at lower doses. Intrathalamic injections of muscimol and mecamylamine decreased per cent correct at doses that did not affect omissions or RT. Intrathalamic scopolamine increased omissions and RT at doses that had little effect on per cent correct. Anatomical controls indicated that the effects of mecamylamine were localized in central thalamus and those of scopolamine were not. Drug effects did not interact with attention-demanding manipulations of stimulus duration, proximity of stimulus and response locations, or stimulus array size. These results are consistent with the hypothesis that central thalamus mediates decisional processes linking sensory stimuli with actions, downstream from systems that detect sensory signals. They also provide evidence that this function is specifically influenced by nicotinic cholinergic receptors.
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Affiliation(s)
- Lori A Newman
- Department of Psychology, University of New Hampshire, Durham, NH 03824, USA
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Clearwater JM, Rennie CJ, Robinson PA. Mean field model of acetylcholine mediated dynamics in the cerebral cortex. BIOLOGICAL CYBERNETICS 2007; 97:449-460. [PMID: 17965874 DOI: 10.1007/s00422-007-0186-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2007] [Accepted: 09/24/2007] [Indexed: 05/25/2023]
Abstract
A recent continuum model of the large scale electrical activity of the cerebral cortex is generalized to include cholinergic modulation. In this model, dynamic modulation of synaptic strength acts over the time scales of nicotinic and muscarinic receptor action. The cortical model is analyzed to determine the effect of acetylcholine (ACh) on its steady states, linear stability, spectrum, and temporal responses to changes in subcortical input. ACh increases the firing rate in steady states of the system. Changing ACh concentration does not introduce oscillatory behavior into the system, but increases the overall spectral power. Model responses to pulses in subcortical input are affected by the tonic level of ACh concentration, with higher levels of ACh increasing the magnitude firing rate response of excitatory cortical neurons to pulses of subcortical input. Numerical simulations are used to explore the temporal dynamics of the model in response to changes in ACh concentration. Evidence is seen of a transition from a state in which intracortical inputs are emphasized to a state where thalamic afferents have enhanced influence. Perturbations in ACh concentration cause changes in the firing rate of cortical neurons, with rapid responses due to fast acting facilitatory effects of nicotinic receptors on subcortical afferents, and slower responses due to muscarinic suppression of intracortical connections. Together, these numerical simulations demonstrate that the actions of ACh could be a significant factor modulating early components of evoked response potentials.
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Affiliation(s)
- J M Clearwater
- School of Physics, University of Sydney, Sydney, NSW 2006, Australia.
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Soto G, Kopell N, Sen K. Network architecture, receptive fields, and neuromodulation: computational and functional implications of cholinergic modulation in primary auditory cortex. J Neurophysiol 2006; 96:2972-83. [PMID: 16899641 DOI: 10.1152/jn.00459.2006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Two fundamental issues in auditory cortical processing are the relative importance of thalamocortical versus intracortical circuits in shaping response properties in primary auditory cortex (ACx), and how the effects of neuromodulators on these circuits affect dynamic changes in network and receptive field properties that enhance signal processing and adaptive behavior. To investigate these issues, we developed a computational model of layers III and IV (LIII/IV) of AI, constrained by anatomical and physiological data. We focus on how the local and global cortical architecture shape receptive fields (RFs) of cortical cells and on how different well-established cholinergic effects on the cortical network reshape frequency-tuning properties of cells in ACx. We identify key thalamocortical and intracortical circuits that strongly affect tuning curves of model cortical neurons and are also sensitive to cholinergic modulation. We then study how differential cholinergic modulation of network parameters change the tuning properties of our model cells and propose two different mechanisms: one intracortical (involving muscarinic receptors) and one thalamocortical (involving nicotinic receptors), which may be involved in rapid plasticity in ACx, as recently reported in a study by Fritz and coworkers.
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Affiliation(s)
- Gabriel Soto
- Department of Biomedical Engineering, Boston University, 44 Cummington Street, Boston, MA 02215, USA
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Liang K, Poytress BS, Chen Y, Leslie FM, Weinberger NM, Metherate R. Neonatal nicotine exposure impairs nicotinic enhancement of central auditory processing and auditory learning in adult rats. Eur J Neurosci 2006; 24:857-66. [PMID: 16848798 DOI: 10.1111/j.1460-9568.2006.04945.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Children of women who smoke cigarettes during pregnancy display cognitive deficits in the auditory-verbal domain. Clinical studies have implicated developmental exposure to nicotine, the main psychoactive ingredient of tobacco, as a probable cause of subsequent auditory deficits. To test for a causal link, we have developed an animal model to determine how neonatal nicotine exposure affects adult auditory function. In adult control rats, nicotine administered systemically (0.7 mg/kg, s.c.) enhanced the sensitivity to sound of neural responses recorded in primary auditory cortex. The effect was strongest in cortical layers 3 and 4, where there is a dense concentration of nicotinic acetylcholine receptors (nAChRs) that has been hypothesized to regulate thalamocortical inputs. In support of the hypothesis, microinjection into layer 4 of the nonspecific nAChR antagonist mecamylamine (10 microM) strongly reduced sound-evoked responses. In contrast to the effects of acute nicotine and mecamylamine in adult control animals, neither drug was as effective in adult animals that had been treated with 5 days of chronic nicotine exposure (CNE) shortly after birth. Neonatal CNE also impaired performance on an auditory-cued active avoidance task, while having little effect on basic auditory or motor functions. Thus, neonatal CNE impairs nicotinic regulation of cortical function, and auditory learning, in the adult. Our results provide evidence that developmental nicotine exposure is responsible for auditory-cognitive deficits in the offspring of women who smoke during pregnancy, and suggest a potential underlying mechanism, namely diminished function of cortical nAChRs.
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Affiliation(s)
- Kevin Liang
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
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Metherate R, Kaur S, Kawai H, Lazar R, Liang K, Rose HJ. Spectral integration in auditory cortex: mechanisms and modulation. Hear Res 2005; 206:146-58. [PMID: 16081005 DOI: 10.1016/j.heares.2005.01.014] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2004] [Accepted: 01/06/2005] [Indexed: 11/19/2022]
Abstract
Auditory cortex contributes to the processing and perception of spectrotemporally complex stimuli. However, the mechanisms by which this is accomplished are not well understood. In this review, we examine evidence that single cortical neurons receive input covering much of the audible spectrum. We then propose an anatomical framework by which spectral information converges on single neurons in primary auditory cortex, via a combination of thalamocortical and intracortical "horizontal" pathways. By its nature, the framework confers sensitivity to specific, spectrotemporally complex stimuli. Finally, to address how spectral integration can be regulated, we show how one neuromodulator, acetylcholine, could act within the hypothesized framework to alter integration in single neurons. The results of these studies promote a cellular understanding of information processing in auditory cortex.
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Affiliation(s)
- Raju Metherate
- Department of Neurobiology and Behavior, University of California, Irvine, 2205 McGaugh Hall, Irvine, CA 92697-4550, United States.
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Tsuneki H, You Y, Toyooka N, Sasaoka T, Nemoto H, Dani JA, Kimura I. Marine Alkaloids (-)-Pictamine and (-)-Lepadin B Block Neuronal Nicotinic Acetylcholine Receptors. Biol Pharm Bull 2005; 28:611-4. [PMID: 15802796 DOI: 10.1248/bpb.28.611] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ascidians (sea squirts) contain a wealth of alkaloids, but their influence over neuronal nicotinic acetylcholine receptors (nAChRs) has not been evaluated. In this study, we examined the effects of two synthetic compounds, (-)-pictamine, a quinolizidine alkaloid from Clavelina picta, and (-)-lepadin B, a decahydroquinoline alkaloid from Clavelina lepadiformis, on major types of neuronal nicotinic receptors (alpha4beta2 and alpha7) expressed in Xenopus oocytes. We found that these alkaloids are potent blockers at these receptors: acetylcholine-elicited currents through alpha4beta2 and alpha7 receptors were blocked by (-)-pictamine with IC(50) values of 1.5 microM and 1.3 microM, respectively, and by (-)-lepadin B with IC(50) values of 0.9 microM and 0.7 microM, respectively. Interestingly, no recovery was observed after the removal of (-)-pictamine in oocytes expressing alpha4beta2 receptors, whereas the inhibited alpha7 currents quickly recovered after the removal of (-)-pictamine. Since there are few compounds that elicit irreversible blocks of alpha4beta2 receptors, (-)-pictamine will be a novel, valuable tool to remove the alpha4beta2-nAChR action from neuronal activities mediated by these two major types of nAChRs.
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Affiliation(s)
- Hiroshi Tsuneki
- Department of Clinical Pharmacology, Toyama Medical and Pharmaceutical University, Japan.
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Metherate R, Hsieh CY. Regulation of glutamate synapses by nicotinic acetylcholine receptors in auditory cortex. Neurobiol Learn Mem 2003; 80:285-90. [PMID: 14521870 DOI: 10.1016/s1074-7427(03)00062-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Acetylcholine plays an important role in regulating the processing of sensory stimuli, and understanding its specific cellular actions is critical to understanding how sensory cortex develops and functions in different behavioral states. Here we review recent work on the cellular effects of nicotinic receptor activation in auditory cortex and describe how these actions could affect systems-level auditory function. In particular, we describe a novel function of nicotinic acetylcholine receptors to regulate glutamate synapses containing N-methyl-D-aspartate receptors during early postnatal development. The transient regulation of developing glutamate synapses also defines a window of vulnerability during which exposure to exogenous nicotine disrupts synapse development. Thus, it appears that nicotinic regulation of glutamate synapses is a critical feature of auditory cortex development.
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Affiliation(s)
- Raju Metherate
- Department of Neurobiology and Behavior, University of California, 2205 McGaugh Hall, Irvine 92697-4550, USA.
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