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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] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [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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Homann J, Koay SA, Chen KS, Tank DW, Berry MJ. Novel stimuli evoke excess activity in the mouse primary visual cortex. Proc Natl Acad Sci U S A 2022; 119:e2108882119. [PMID: 35101916 PMCID: PMC8812573 DOI: 10.1073/pnas.2108882119] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/14/2021] [Indexed: 01/03/2023] Open
Abstract
Rapid detection and processing of stimulus novelty are key elements of adaptive behavior. Predictive coding theories postulate that novel stimuli should be encoded differently from familiar stimuli. Here, we show that the majority of neurons in layer 2/3 of the mouse primary visual cortex exhibit a significant excess response to novel visual stimuli. The distinction between novel and familiar images developed rapidly, requiring only a few repeated presentations. We show that this phenomenon can be described by a model of cascading adaptation. This ubiquitous mechanism makes it likely that similar computations could be carried out in many brain areas. To explore how neural circuits represent novel versus familiar inputs, we presented mice with repeated sets of images with novel images sparsely substituted. Using two-photon calcium imaging to record from layer 2/3 neurons in the mouse primary visual cortex, we found that novel images evoked excess activity in the majority of neurons. This novelty response rapidly emerged, arising with a time constant of 2.6 ± 0.9 s. When a new image set was repeatedly presented, a majority of neurons had similarly elevated activity for the first few presentations, which decayed to steady state with a time constant of 1.4 ± 0.4 s. When we increased the number of images in the set, the novelty response’s amplitude decreased, defining a capacity to store ∼15 familiar images under our conditions. These results could be explained quantitatively using an adaptive subunit model in which presynaptic neurons have individual tuning and gain control. This result shows that local neural circuits can create different representations for novel versus familiar inputs using generic, widely available mechanisms.
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Avram M, Grothe MJ, Meinhold L, Leucht C, Leucht S, Borgwardt S, Brandl F, Sorg C. Lower cholinergic basal forebrain volumes link with cognitive difficulties in schizophrenia. Neuropsychopharmacology 2021; 46:2320-2329. [PMID: 34188186 PMCID: PMC8580980 DOI: 10.1038/s41386-021-01070-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 06/01/2021] [Accepted: 06/12/2021] [Indexed: 02/06/2023]
Abstract
A potential pathophysiological mechanism of cognitive difficulties in schizophrenia is a dysregulated cholinergic system. Particularly, the cholinergic basal forebrain nuclei (BFCN), the source of cortical cholinergic innervation, support multiple cognitive functions, ranging from attention to decision-making. We hypothesized that BFCN structural integrity is altered in schizophrenia and associated with patients' attentional deficits. We assessed gray matter (GM) integrity of cytoarchitectonically defined BFCN region-of-interest in 72 patients with schizophrenia and 73 healthy controls, matched for age and gender, from the COBRE open-source database, via structural magnetic resonance imaging (MRI)-based volumetry. MRI-derived measures of GM integrity (i.e., volumes) were linked with performance on a symbol coding task (SCT), a paper-pencil-based metric that assesses attention, by correlation and mediation analysis. To assess the replicability of findings, we repeated the analyses in an independent dataset comprising 26 patients with schizophrenia and 24 matched healthy controls. BFCN volumes were lower in patients (t(139)=2.51, p = 0.01) and significantly associated with impaired SCT performance (r = 0.31, p = 0.01). Furthermore, lower BFCN volumes mediated the group difference in SCT performance. When including global GM volumes, which were lower in patients, as covariates-of-no-interest, these findings disappeared, indicating that schizophrenia did not have a specific effect on BFCN relative to other regional volume changes. We replicated these findings in the independent cohort, e.g., BFCN volumes were lower in patients and mediated patients' impaired SCT performance. Results demonstrate lower BFCN volumes in schizophrenia, which link with patients' attentional deficits. Data suggest that a dysregulated cholinergic system might contribute to cognitive difficulties in schizophrenia via impaired BFCN.
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Affiliation(s)
- Mihai Avram
- Department of Psychiatry and Psychotherapy, Schleswig Holstein University Hospital, University of Lübeck, Lübeck, 23538, Germany.
| | - Michel J. Grothe
- grid.414816.e0000 0004 1773 7922Unidad de Trastornos del Movimiento, Servicio de Neurología y Neurofisiología Clínica, Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Sevilla, Spain
| | - Lena Meinhold
- grid.6936.a0000000123222966TUM-NIC Neuroimaging Center, Technical University of Munich, School of Medicine, Munich, 81675 Germany
| | - Claudia Leucht
- grid.6936.a0000000123222966Department of Psychiatry and Psychotherapy, Technical University of Munich, School of Medicine, Munich, 81675 Germany
| | - Stefan Leucht
- grid.6936.a0000000123222966Department of Psychiatry and Psychotherapy, Technical University of Munich, School of Medicine, Munich, 81675 Germany
| | - Stefan Borgwardt
- grid.4562.50000 0001 0057 2672Department of Psychiatry and Psychotherapy, Schleswig Holstein University Hospital, University of Lübeck, Lübeck, 23538 Germany
| | - Felix Brandl
- grid.6936.a0000000123222966TUM-NIC Neuroimaging Center, Technical University of Munich, School of Medicine, Munich, 81675 Germany ,grid.6936.a0000000123222966Department of Psychiatry and Psychotherapy, Technical University of Munich, School of Medicine, Munich, 81675 Germany ,grid.6936.a0000000123222966Department of Neuroradiology, Technical University of Munich, School of Medicine, Munich, 81675 Germany
| | - Christian Sorg
- grid.6936.a0000000123222966TUM-NIC Neuroimaging Center, Technical University of Munich, School of Medicine, Munich, 81675 Germany ,grid.6936.a0000000123222966Department of Psychiatry and Psychotherapy, Technical University of Munich, School of Medicine, Munich, 81675 Germany ,grid.6936.a0000000123222966Department of Neuroradiology, Technical University of Munich, School of Medicine, Munich, 81675 Germany
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Lozano-Montes L, Dimanico M, Mazloum R, Li W, Nair J, Kintscher M, Schneggenburger R, Harvey M, Rainer G. Optogenetic Stimulation of Basal Forebrain Parvalbumin Neurons Activates the Default Mode Network and Associated Behaviors. Cell Rep 2020; 33:108359. [PMID: 33176133 DOI: 10.1016/j.celrep.2020.108359] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 05/25/2020] [Accepted: 10/16/2020] [Indexed: 11/20/2022] Open
Abstract
Activation of the basal forebrain (BF) has been associated with increased attention, arousal, and a heightened cortical representation of the external world. In addition, BF has been implicated in the regulation of the default mode network (DMN) and associated behaviors. Here, we provide causal evidence for a role of BF in DMN regulation, highlighting a prominent role of parvalbumin (PV) GABAergic neurons. The optogenetic activation of BF PV neurons reliably drives animals toward DMN-like behaviors, with no effect on memory encoding. In contrast, BF electrical stimulation enhances memory performance and increases DMN-like behaviors. BF stimulation has a correlated impact on peptide regulation in the BF and ACC, enhancing peptides linked to grooming behavior and memory functions, supporting a crucial role of the BF in DMN regulation. We suggest that in addition to enhancing attentional functions, the BF harbors a network encompassing PV GABAergic neurons that promotes self-directed behaviors associated with the DMN.
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Krueger J, Disney AA. Structure and function of dual-source cholinergic modulation in early vision. J Comp Neurol 2018; 527:738-750. [PMID: 30520037 DOI: 10.1002/cne.24590] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 10/29/2018] [Accepted: 11/01/2018] [Indexed: 12/21/2022]
Abstract
Behavioral states such as arousal and attention have profound effects on sensory processing, determining how-even whether-a stimulus is perceived. This state-dependence is believed to arise, at least in part, in response to inputs from subcortical structures that release neuromodulators such as acetylcholine, often nonsynaptically. The mechanisms that underlie the interaction between these nonsynaptic signals and the more point-to-point synaptic cortical circuitry are not well understood. This review highlights the state of the field, with a focus on cholinergic action in early visual processing. Key anatomical and physiological features of both the cholinergic and the visual systems are discussed. Furthermore, presenting evidence of cholinergic modulation in visual thalamus and primary visual cortex, we explore potential functional roles of acetylcholine and its effects on the processing of visual input over the sleep-wake cycle, sensory gain control during wakefulness, and consider evidence for cholinergic support of visual attention.
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Affiliation(s)
- Juliane Krueger
- Department of Neurobiology, Duke University School of Medicine, Durham, North Carolina
| | - Anita A Disney
- Department of Neurobiology, Duke University School of Medicine, Durham, North Carolina
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Boukrina O, Barrett AM. Disruption of the ascending arousal system and cortical attention networks in post-stroke delirium and spatial neglect. Neurosci Biobehav Rev 2017; 83:1-10. [PMID: 28963037 DOI: 10.1016/j.neubiorev.2017.09.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 08/11/2017] [Accepted: 09/22/2017] [Indexed: 11/22/2022]
Abstract
Delirium is an acute attention and cognitive dysfunction, adversely affecting functional outcomes and mortality. As many as half of hospitalized right brain stroke survivors may develop delirium. Further, about 50% of right stroke patients experience spatial neglect, impairing safety and recovery. In this review we explore the brain mechanisms, which may explain the high incidence of delirium and spatial neglect after right-brain stroke. We suggest that brain networks for spatial attention and arousal, composed of ascending projections from the midbrain nuclei and integrating dorsal and ventral cortical and limbic components, may underlie impairments in delirium and spatial neglect. We propose that lateralized deficits in spatial neglect may arise because cortical and limbic components of these functional networks are disproportionally impaired by right-brain strokes, and that spatial neglect may lower the threshold for developing delirium. An improved understanding of the brain basis of delirium and spatial neglect could provide a critical biomarker for initiating preventive care in stroke patients at high risk of hospital morbidity and loss of independence.
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Affiliation(s)
- Olga Boukrina
- Stroke Rehabilitation Research, Kessler Foundation, 1199 Pleasant Valley Way, West Orange, NJ, 07052, USA.
| | - A M Barrett
- Stroke Rehabilitation Research, Kessler Foundation, 1199 Pleasant Valley Way, West Orange, NJ, 07052, USA; Department of Physical Medicine and Rehabilitation, Rutgers-New Jersey Medical School, 185 S Orange Avenue, Newark, NJ, 07103, USA; Kessler Institute for Rehabilitation, 1199 Pleasant Valley Way, West Orange, NJ, USA.
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Shimegi S, Kimura A, Sato A, Aoyama C, Mizuyama R, Tsunoda K, Ueda F, Araki S, Goya R, Sato H. Cholinergic and serotonergic modulation of visual information processing in monkey V1. ACTA ACUST UNITED AC 2016; 110:44-51. [PMID: 27619519 DOI: 10.1016/j.jphysparis.2016.09.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 08/24/2016] [Accepted: 09/08/2016] [Indexed: 11/30/2022]
Abstract
The brain dynamically changes its input-output relationship depending on the behavioral state and context in order to optimize information processing. At the molecular level, cholinergic/monoaminergic transmitters have been extensively studied as key players for the state/context-dependent modulation of brain function. In this paper, we review how cortical visual information processing in the primary visual cortex (V1) of macaque monkey, which has a highly differentiated laminar structure, is optimized by serotonergic and cholinergic systems by examining anatomical and in vivo electrophysiological aspects to highlight their similarities and distinctions. We show that these two systems have a similar layer bias for axonal fiber innervation and receptor distribution. The common target sites are the geniculorecipient layers and geniculocortical fibers, where the appropriate gain control is established through a geniculocortical signal transformation. Both systems exert activity-dependent response gain control across layers, but in a manner consistent with the receptor subtype. The serotonergic receptors 5-HT1B and 5HT2A modulate the contrast-response curve in a manner consistent with bi-directional response gain control, where the sign (facilitation/suppression) is switched according to the firing rate and is complementary to the other. On the other hand, cholinergic nicotinic/muscarinic receptors exert mono-directional response gain control without a sign reversal. Nicotinic receptors increase the response magnitude in a multiplicative manner, while muscarinic receptors exert both suppressive and facilitative effects. We discuss the implications of the two neuromodulator systems in hierarchical visual signal processing in V1 on the basis of the developed laminar structure.
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Affiliation(s)
- Satoshi Shimegi
- Graduate School of Medicine, Osaka University, Toyonaka, Osaka 560-0043, Japan; Graduate School of Frontier Biosciences, Osaka University, Toyonaka, Osaka 560-0043, Japan.
| | - Akihiro Kimura
- Department of Healthcare, Osaka Health Science University, Toyonaka, Osaka 560-0043, Japan
| | - Akinori Sato
- Graduate School of Frontier Biosciences, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Chisa Aoyama
- Graduate School of Frontier Biosciences, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Ryo Mizuyama
- Graduate School of Frontier Biosciences, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Keisuke Tsunoda
- Graduate School of Frontier Biosciences, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Fuyuki Ueda
- Graduate School of Frontier Biosciences, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Sera Araki
- Graduate School of Frontier Biosciences, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Ryoma Goya
- Graduate School of Sports and Health Science, Fukuoka University, Fukuoka 814-0180, Japan
| | - Hiromichi Sato
- Graduate School of Medicine, Osaka University, Toyonaka, Osaka 560-0043, Japan; Graduate School of Frontier Biosciences, Osaka University, Toyonaka, Osaka 560-0043, Japan
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Bokde ALW, Cavedo E, Lopez-Bayo P, Lista S, Meindl T, Born C, Galluzzi S, Faltraco F, Dubois B, Teipel SJ, Reiser M, Möller HJ, Hampel H. Effects of rivastigmine on visual attention in subjects with amnestic mild cognitive impairment: A serial functional MRI activation pilot-study. Psychiatry Res Neuroimaging 2016; 249:84-90. [PMID: 26851974 DOI: 10.1016/j.pscychresns.2016.01.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 01/08/2016] [Accepted: 01/14/2016] [Indexed: 10/22/2022]
Abstract
A pilot study to investigate the effects of rivastigmine on the brain activation pattern due to visual attention tasks in a group of amnestic Mild Cognitive Impaired patients (aMCI). The design was an initial three-month double blind period with a rivastigmine and placebo arms, followed by a nine-month open-label period. All patients underwent serial functional magnetic resonance imaging (fMRI) at baseline, and after three and six months of follow-up. Primary endpoint was the effect of rivastigmine on functional brain changes during visual attention (face and location matching) tasks. There were five in the rivastigmine arm and two in the placebo arm. The face matching task showed higher activation of visual areas after three months of treatment but no differences compared to baseline at six months. The location matching task showed a higher activation along the dorsal visual pathway at both three and six months follow ups. Treatment with rivastigmine demonstrates a significant effect on brain activation of the dorsal visual pathway during a location matching task in patients with aMCI. Our data support the potential use of task fMRI to map specific treatment effects of cholinergic drugs during prodromal stages of Alzheimer's disease (AD).
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Affiliation(s)
- Arun L W Bokde
- Discipline of Psychiatry, School of Medicine and Trinity College Institute of Neuroscience (TCIN), Trinity College Dublin, Dublin 2, Ireland; Department of Psychiatry, Ludwig-Maximilian University, Nussbaumstrasse 7, 80336 Munich, Germany.
| | - Enrica Cavedo
- Sorbonne Universités, Université Pierre et Marie Curie, Paris 06, Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A) & Institut du Cerveau et de la Moelle Épinière (ICM), Département de Neurologie, Hôpital de la Pitié-Salpétrière, Paris, France; CATI Multicenter Neuroimaging Platform, France; Unità di Neuroimmagine e Epidemiologia Alzheimer, IRCCS Istituto Centro San Giovanni di Dio-Fatebenefratelli, Italy
| | - Patricia Lopez-Bayo
- Department of Psychiatry, Ludwig-Maximilian University, Nussbaumstrasse 7, 80336 Munich, Germany
| | - Simone Lista
- Sorbonne Universités, Université Pierre et Marie Curie, Paris 06, Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A) & Institut du Cerveau et de la Moelle Épinière (ICM), Département de Neurologie, Hôpital de la Pitié-Salpétrière, Paris, France; AXA Research Fund & UPMC Chair, Paris, France
| | - Thomas Meindl
- Institute for Clinical Radiology, Ludwig-Maximilian University, Munich, Germany
| | - Christine Born
- Institute for Clinical Radiology, Ludwig-Maximilian University, Munich, Germany
| | - Samantha Galluzzi
- Unità di Neuroimmagine e Epidemiologia Alzheimer, IRCCS Istituto Centro San Giovanni di Dio-Fatebenefratelli, Italy
| | - Frank Faltraco
- Department of Psychiatry, Psychotherapy and Psychosomatics, Immanuel Clinic Rüdersdorf, Medical School Brandenburg, Seebad 82/83, 15562 Rüdersdorf bei Berlin, Germany
| | - Bruno Dubois
- Sorbonne Universités, Université Pierre et Marie Curie, Paris 06, Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A) & Institut du Cerveau et de la Moelle Épinière (ICM), Département de Neurologie, Hôpital de la Pitié-Salpétrière, Paris, France
| | - Stefan J Teipel
- Department of Psychosomatic Medicine, University of Rostock, Rostock, Germany; German Center for Neurodegenerative Diseases (DZNE), Rostock, Germany
| | - Maximilian Reiser
- Institute for Clinical Radiology, Ludwig-Maximilian University, Munich, Germany
| | - Hans-Jürgen Möller
- Department of Psychiatry, Ludwig-Maximilian University, Nussbaumstrasse 7, 80336 Munich, Germany
| | - Harald Hampel
- Sorbonne Universités, Université Pierre et Marie Curie, Paris 06, Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A) & Institut du Cerveau et de la Moelle Épinière (ICM), Département de Neurologie, Hôpital de la Pitié-Salpétrière, Paris, France; AXA Research Fund & UPMC Chair, Paris, France
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Boucart M, Bubbico G, Szaffarczyk S, Defoort S, Ponchel A, Waucquier N, Deplanque D, Deguil J, Bordet R. Donepezil increases contrast sensitivity for the detection of objects in scenes. Behav Brain Res 2015; 292:443-7. [PMID: 26162753 DOI: 10.1016/j.bbr.2015.06.037] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 06/25/2015] [Accepted: 06/28/2015] [Indexed: 11/18/2022]
Abstract
We assessed the effects of donepezil, a drug that stimulates cholinergic transmission, and scopolamine, an antagonist of cholinergic transmission, on contrast sensitivity. 30 young male participants were tested under three treatment conditions: placebo, donepezil, and scopolamine in a random order. Pairs of photographs varying in contrast were displayed left and right of fixation for 50 ms. Participants were asked to locate the scene containing an animal. Accuracy was better under donepezil than under scopolamine, particularly for signals of high intensity (at higher levels of contrast). A control experiment showed that the lower performance under scopolamine did not result from the mydriasis induced by scopolamine. The results suggest that cholinergic stimulation, through donepezil, facilitates signal detection in agreement with studies on animals showing that the pharmacological activation of cholinergic receptors controls the gain in the relationship between the stimulus contrast (intensity of the visual input) and visual response. As Alzheimer disease is associated to depletion in acetylcholine, and there is evidence of deficits in contrast sensitivity in Alzheimer, it might be interesting to integrate such rapid and sensitive visual tasks in the biomarkers at early stage of drug development.
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Affiliation(s)
- Muriel Boucart
- Laboratoire de Sciences Cognitives et Affectives SCALab, Université de Lille, CNRS, France.
| | - Giovanna Bubbico
- Laboratoire de Sciences Cognitives et Affectives SCALab, Université de Lille, CNRS, France
| | - Sebastien Szaffarczyk
- Laboratoire de Sciences Cognitives et Affectives SCALab, Université de Lille, CNRS, France
| | - Sabine Defoort
- Laboratoire de Sciences Cognitives et Affectives SCALab, Université de Lille, CNRS, France
| | - Amelie Ponchel
- U1171, Université de Lille, INSERM, Centre Hospitalier et Universitaire, Lille, France
| | - Nawal Waucquier
- CIC1403, Université de Lille, INSERM, Centre Hospitalier et Universitaire, Lille, France
| | - Dominique Deplanque
- U1171, Université de Lille, INSERM, Centre Hospitalier et Universitaire, Lille, France; CIC1403, Université de Lille, INSERM, Centre Hospitalier et Universitaire, Lille, France
| | - Julie Deguil
- U1171, Université de Lille, INSERM, Centre Hospitalier et Universitaire, Lille, France
| | - Régis Bordet
- U1171, Université de Lille, INSERM, Centre Hospitalier et Universitaire, Lille, France
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Fu Y, Tucciarone JM, Espinosa JS, Sheng N, Darcy DP, Nicoll RA, Huang ZJ, Stryker MP. A cortical circuit for gain control by behavioral state. Cell 2014; 156:1139-1152. [PMID: 24630718 DOI: 10.1016/j.cell.2014.01.050] [Citation(s) in RCA: 578] [Impact Index Per Article: 57.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 11/25/2013] [Accepted: 01/10/2014] [Indexed: 11/30/2022]
Abstract
The brain's response to sensory input is strikingly modulated by behavioral state. Notably, the visual response of mouse primary visual cortex (V1) is enhanced by locomotion, a tractable and accessible example of a time-locked change in cortical state. The neural circuits that transmit behavioral state to sensory cortex to produce this modulation are unknown. In vivo calcium imaging of behaving animals revealed that locomotion activates vasoactive intestinal peptide (VIP)-positive neurons in mouse V1 independent of visual stimulation and largely through nicotinic inputs from basal forebrain. Optogenetic activation of VIP neurons increased V1 visual responses in stationary awake mice, artificially mimicking the effect of locomotion, and photolytic damage of VIP neurons abolished the enhancement of V1 responses by locomotion. These findings establish a cortical circuit for the enhancement of visual response by locomotion and provide a potential common circuit for the modulation of sensory processing by behavioral state.
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Affiliation(s)
- Yu Fu
- Center for Integrative Neuroscience, Department of Physiology, University of California, 675 Nelson Rising Road, San Francisco, CA 94158, USA.
| | - Jason M Tucciarone
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA; MSTP/Neuroscience graduate Program, Stony Brook University, Stony Brook, NY 11790, USA
| | - J Sebastian Espinosa
- Center for Integrative Neuroscience, Department of Physiology, University of California, 675 Nelson Rising Road, San Francisco, CA 94158, USA
| | - Nengyin Sheng
- Departments of Cellular and Molecular Pharmacology and Physiology, University of California, San Francisco, CA 94158, USA
| | - Daniel P Darcy
- Center for Integrative Neuroscience, Department of Physiology, University of California, 675 Nelson Rising Road, San Francisco, CA 94158, USA
| | - Roger A Nicoll
- Departments of Cellular and Molecular Pharmacology and Physiology, University of California, San Francisco, CA 94158, USA
| | - Z Josh Huang
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | - Michael P Stryker
- Center for Integrative Neuroscience, Department of Physiology, University of California, 675 Nelson Rising Road, San Francisco, CA 94158, USA.
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Handjaras G, Ricciardi E, Szczepanik J, Pietrini P, Furey ML. Cholinergic enhancement differentially modulates neural response to encoding during face identity and face location working memory tasks. Exp Biol Med (Maywood) 2013; 238:999-1008. [PMID: 23975732 DOI: 10.1177/1535370213497326] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Potentiation of cholinergic transmission influences stimulus processing by enhancing signal detection through suppression and/or filtering out of irrelevant information (bottom-up modulation) and with top-down task-oriented executive mechanisms based on the recruitment of prefrontal and parietal attentional systems. The cholinergic system also plays a critical role in working memory (WM) processes and preferentially modulates WM encoding, likely through stimulus-processing mechanisms. Previous research reported increased brain responses in visual extrastriate cortical regions during cholinergic enhancement in the encoding phase of WM, independently addressing object and spatial encoding. The current study used functional magnetic resonance imaging to determine the effects of cholinergic enhancement on encoding of key visual processing features. Subjects participated in two scanning sessions, one during an intravenous (i.v.) infusion of saline and the other during an infusion of the acetylcholinesterase inhibitor physostigmine. In each scan session, subjects alternated between a face identity recognition and a spatial location WM. Enhanced cholinergic function increased neural activity in the ventral stream during encoding of face identity and in the dorsal stream during encoding of face location. Conversely, a reduction in brain response was found for scrambled sensorimotor control images. The cholinergic effects on neural activity in the ventral stream during encoding of face identity were stronger than those observed in the dorsal stream during encoding of face location, likely as a consequence of the role of acetylcholine in establishing the inherently relevant nature of face identity. Despite the limited sample-size, the results suggest the stimulus-dependent role of cholinergic system in signal detection, as they show that cholinergic potentiation enhances neural activity in regions associated with early perceptual processing in a selective manner depending on the attended stimulus feature.
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Affiliation(s)
- Giacomo Handjaras
- Laboratory of Clinical Biochemistry and Molecular Biology, University of Pisa, Pisa 56126, Italy
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Polack PO, Friedman J, Golshani P. Cellular mechanisms of brain state-dependent gain modulation in visual cortex. Nat Neurosci 2013; 16:1331-9. [PMID: 23872595 DOI: 10.1038/nn.3464] [Citation(s) in RCA: 400] [Impact Index Per Article: 36.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Accepted: 06/11/2013] [Indexed: 12/20/2022]
Abstract
During locomotion, visual cortical neurons fire at higher rates to visual stimuli than during immobility while maintaining orientation selectivity. The mechanisms underlying this change in gain are not understood. We performed whole cell recordings from layer 2/3 and layer 4 visual cortical excitatory neurons as well as from parvalbumin-positive and somatostatin-positive inhibitory neurons in mice free to rest or run on a spherical treadmill. We found that the membrane potential of all cell types became more depolarized and (with the exception of somatostatin-positive interneurons) less variable during locomotion. Cholinergic input was essential for maintaining the unimodal membrane potential distribution during immobility, while noradrenergic input was necessary for the tonic depolarization associated with locomotion. Our results provide a mechanism for how neuromodulation controls the gain and signal-to-noise ratio of visual cortical neurons during changes in the state of vigilance.
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Affiliation(s)
- Alexander Thiele
- Institute of Neuroscience, Henry Wellcome Building, Newcastle University, Newcastle upon Tyne, NE2 4HH, United Kingdom;
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Soma S, Shimegi S, Suematsu N, Sato H. Cholinergic modulation of response gain in the rat primary visual cortex. Sci Rep 2013; 3:1138. [PMID: 23378897 DOI: 10.1038/srep01138] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 12/27/2012] [Indexed: 12/24/2022] Open
Abstract
Acetylcholine (ACh) is known to modulate neuronal activity in the rodent primary visual cortex (V1). Although cholinergic modulation has been extensively examined in vitro, far less is understood regarding how ACh modulates visual information processing in vivo. We therefore extracellularly recorded visual responses to drifting sinusoidal grating stimuli from V1 of anesthetized rats and tested the effects of ACh administered locally by microiontophoresis. ACh exerted response facilitation or suppression in individual neurons across all cortical layers without any laminar bias. We assessed ACh effects on the stimulus contrast-response function, finding that ACh increased or decreased the response to varying stimulus contrasts in proportion to the magnitude of the control response without changing the shape of the original contrast-response function, which describes response gain control but not contrast gain control. Our results indicate that ACh serves as a gain controller in the visual cortex of rodents.
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Abstract
Attentional impairments are found in a range of neurodegenerative and neuropsychiatric disorders. However, the development of procognitive enhancers to alleviate these impairments has been hindered by a lack of comprehensive hypotheses regarding the circuitry mediating the targeted attentional functions. Here we discuss the role of the cortical cholinergic system in mediating cue detection and attentional control and propose two target mechanisms for cognition enhancers: stimulation of prefrontal α4β2* nicotinic acetylcholine receptors (nAChR) for the enhancement of cue detection and augmentation of tonic acetylcholine levels for the enhancement of attentional control. This article is part of a Special Issue entitled 'Cognitive Enhancers'.
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Affiliation(s)
- Elise Demeter
- Psychiatry Department, 4250 Plymouth Road, University of Michigan, Ann Arbor, MI 48109-5765, USA.
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16
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Abstract
ACh modulates neuronal activity throughout the cerebral cortex, including the primary visual cortex (V1). However, a number of issues regarding this modulation remain unknown, such as the effect and its function and the receptor subtypes involved. To address these issues, we combined extracellular single-unit recordings and microiontophoretic administration of ACh and measured V1 neuronal responses to drifting sinusoidal grating stimuli in anesthetized macaque monkeys. ACh was found to have mostly facilitatory effects on the visual responses, although some cases of suppressive effects were also seen. To assess the functional role of ACh, we further examined how ACh modulates the stimulus contrast-response function, finding that the response gain increased with the facilitatory effect. The response facilitation was completely or strongly blocked by atropine (At), a muscarinic ACh receptor (mAChR) antagonist, in almost all neurons (96% of cells), whereas any residual effect after At administration was fully removed by mecamylamine, a nicotinic AChR (nAChR) antagonist, suggesting a predominant role for mAChRs in this mechanism. Furthermore, we found no laminar distribution bias for the facilitatory modulation, although the relative contribution of mAChRs was smaller in layer 4C than in other layers. The suppressive effect was blocked completely by At. These results demonstrate that ACh plays an important role in visual information processing in V1 by controlling the response gain via mAChRs across all cortical layers and via nAChRs, mainly in layer 4C.
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Affiliation(s)
- Shogo Soma
- Graduate Schools of Frontier Biosciences and Medicine, Osaka Univ., 1-17 Machikaneyama, Toyonaka, Osaka, Japan
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Bentley P, Driver J, Dolan RJ. Cholinergic modulation of cognition: insights from human pharmacological functional neuroimaging. Prog Neurobiol 2011; 94:360-88. [PMID: 21708219 DOI: 10.1016/j.pneurobio.2011.06.002] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Revised: 06/02/2011] [Accepted: 06/07/2011] [Indexed: 11/22/2022]
Abstract
Evidence from lesion and cortical-slice studies implicate the neocortical cholinergic system in the modulation of sensory, attentional and memory processing. In this review we consider findings from sixty-three healthy human cholinergic functional neuroimaging studies that probe interactions of cholinergic drugs with brain activation profiles, and relate these to contemporary neurobiological models. Consistent patterns that emerge are: (1) the direction of cholinergic modulation of sensory cortex activations depends upon top-down influences; (2) cholinergic hyperstimulation reduces top-down selective modulation of sensory cortices; (3) cholinergic hyperstimulation interacts with task-specific frontoparietal activations according to one of several patterns, including: suppression of parietal-mediated reorienting; decreasing ‘effort’-associated activations in prefrontal regions; and deactivation of a ‘resting-state network’ in medial cortex, with reciprocal recruitment of dorsolateral frontoparietal regions during performance-challenging conditions; (4) encoding-related activations in both neocortical and hippocampal regions are disrupted by cholinergic blockade, or enhanced with cholinergic stimulation, while the opposite profile is observed during retrieval; (5) many examples exist of an ‘inverted-U shaped’ pattern of cholinergic influences by which the direction of functional neural activation (and performance) depends upon both task (e.g. relative difficulty) and subject (e.g. age) factors. Overall, human cholinergic functional neuroimaging studies both corroborate and extend physiological accounts of cholinergic function arising from other experimental contexts, while providing mechanistic insights into cholinergic-acting drugs and their potential clinical applications.
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Madhusoodanan S, Madhusoodanan N, Serper M, Sullivan SJ, D'Antonio E, Negi R, Brenner R. Cognitive status changes based on time of day in nursing home patients with and without dementia. Am J Alzheimers Dis Other Demen 2010; 25:498-504. [PMID: 20558850 PMCID: PMC10845484 DOI: 10.1177/1533317510372373] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2024]
Abstract
BACKGROUND Changes in behavior and cognition have been observed with disruption of the circadian rhythm. METHODS This study examined the effects of time of day (TOD) on administration of Mini-Mental State Examinations (MMSEs) in nursing home patients with dementia (patients) or functional psychiatric disorders (control), using repeated measures analyses of covariance (ANCOVAs). RESULTS Controls (n = 34) scored significantly higher than patients (n = 38) on total MMSE and all subscales. Within the patients, men and women performed equally in the morning, but women performed marginally worse in the afternoon on total MMSE scores, orientation, and immediate recall and men performed significantly better in the afternoon. Within the control, no gender or time effects were detected. CONCLUSION Results indicate that TOD had no significant impact on cognitive status in patients with dementia or patients with other psychiatric illnesses. No changes in activity timings are recommended in nursing home patients with dementia.
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Abstract
The pros and cons of estrogen therapy for use in postmenopausal women continue to be a major topic of debate in women's health. Much of this debate focuses on the potential benefits vs. harm of estrogen therapy on the brain and the risks for cognitive impairment associated with aging and Alzheimer's disease. Many animal and human studies suggest that estrogens can have significant beneficial effects on brain aging and cognition and reduce the risk of Alzheimer's-related dementia; however, others disagree. Important discoveries have been made, and hypotheses have emerged that may explain some of the inconsistencies. This review focuses on the cholinergic hypothesis, specifically on evidence that beneficial effects of estrogens on brain aging and cognition are related to interactions with cholinergic projections emanating from the basal forebrain. These cholinergic projections play an important role in learning and attentional processes, and their function is known to decline with advanced age and in association with Alzheimer's disease. Evidence suggests that many of the effects of estrogens on neuronal plasticity and function and cognitive performance are related to or rely upon interactions with these cholinergic projections; however, studies also suggest that the effectiveness of estrogen therapy decreases with age and time after loss of ovarian function. We propose a model in which deficits in basal forebrain cholinergic function contribute to age-related changes in the response to estrogen therapy. Based on this model, we propose that cholinergic-enhancing drugs, used in combination with an appropriate estrogen-containing drug regimen, may be a viable therapeutic strategy for use in older postmenopausal women with early evidence of mild cognitive decline.
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Affiliation(s)
- Robert B Gibbs
- University of Pittsburgh School of Pharmacy, 1004 Salk Hall, Pittsburgh, Pennsylvania 15261, USA.
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Bokde AL, Karmann M, Teipel SJ, Born C, Lieb M, Reiser MF, Möller HJ, Hampel H. Decreased activation along the dorsal visual pathway after a 3-month treatment with galantamine in mild Alzheimer disease: a functional magnetic resonance imaging study. J Clin Psychopharmacol 2009; 29:147-56. [PMID: 19512976 DOI: 10.1097/JCP.0b013e31819a8f2e] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Visual perception has been shown to be altered in Alzheimer disease (AD) patients, and it is associated with decreased cognitive function. Galantamine is an active cholinergic agent, which has been shown to lead to improved cognition in mild to moderate AD patients. This study examined brain activation in a group of mild AD patients after a 3-month open-label treatment with galantamine. The objective was to examine the changes in brain activation due to treatment. There were 2 tasks to visual perception. The first task was a face-matching task to test the activation along the ventral visual pathway, and the second task was a location-matching task to test neuronal function along the dorsal pathway. Brain activation was measured using functional magnetic resonance imaging. There were 5 mild AD patients in the study. There were no differences in the task performance and in the cognitive scores of the Consortium to Establish a Registry for Alzheimer's Disease battery before and after treatment. In the location-matching task, we found a statistically significant decrease in activation along the dorsal visual pathway after galantamine treatment. A previous study found that AD patients had higher activation in the location-matching task compared with healthy controls. There were no differences in activation for the face-matching task after treatment. Our data indicate that treatment with galantamine leads to more efficient visual processing of stimuli or changes the compensatory mechanism in the AD patients. A visual perception task recruiting the dorsal visual system may be useful as a biomarker of treatment effects.
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Chan KC, So KF, Wu EX. Proton magnetic resonance spectroscopy revealed choline reduction in the visual cortex in an experimental model of chronic glaucoma. Exp Eye Res 2008; 88:65-70. [PMID: 18992243 DOI: 10.1016/j.exer.2008.10.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Revised: 09/28/2008] [Accepted: 10/02/2008] [Indexed: 11/20/2022]
Abstract
Glaucoma is a neurodegenerative disease of the visual system. While elevated intraocular pressure is considered to be a major risk factor, the primary cause and pathogenesis of this disease are still unclear. This study aims to employ in vivo proton magnetic resonance spectroscopy ((1)H MRS) to evaluate the metabolic changes in the visual cortex in a rat model of chronic glaucoma. Five Sprague-Dawley female rats were prepared to induce ocular hypertension unilaterally in the right eye by photocoagulating the episcleral and limbal veins using an argon laser. Single voxel (1)H MRS was performed on each side of the visual cortex 6 weeks after laser treatment. Relative to the creatine level, the choline level was found to be significantly lower in the left glaucomatous visual cortex than the right control visual cortex in all animals. In addition, a marginally significant increase in glutamate level was observed in the glaucomatous visual cortex. No apparent difference was observed between contralateral sides of the visual cortex in T1-weighted or T2-weighted imaging. The results of this study showed that glaucoma is accompanied with alterations in the metabolism of choline-containing compounds in the visual cortex contralateral to the glaucomatous rat eye. These potentially associated the pathophysiological mechanisms of glaucoma with the dysfunction of the cholinergic system in the visual pathway. (1)H MRS is a potential tool for studying the metabolic changes in glaucoma in vivo in normally appearing brain structures, and may possess direct clinical applications for humans. Measurement of the Cho:Cr reduction in the visual cortex may be a noninvasive biomarker for this disease.
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Affiliation(s)
- Kevin C Chan
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong
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22
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Abstract
Acetylcholine is a ubiquitous cortical neuromodulator implicated in cognition. In order to understand the potential for acetylcholine to play a role in visual attention, we studied nicotinic acetylcholine receptor (nAChR) localization and function in area V1 of the macaque. We found nAChRs presynaptically at thalamic synapses onto excitatory, but not inhibitory, neurons in the primary thalamorecipient layer 4c. Furthermore, consistent with the release enhancement suggested by this localization, we discovered that nicotine increases responsiveness and lowers contrast threshold in layer 4c neurons. We also found that nAChRs are expressed by GABAergic interneurons in V1 but rarely by pyramidal neurons, and that nicotine suppresses visual responses outside layer 4c. All sensory systems incorporate gain control mechanisms, or processes which dynamically alter input/output relationships. We demonstrate that at the site of thalamic input to visual cortex, the effect of this nAChR-mediated gain is an enhancement of the detection of visual stimuli.
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Affiliation(s)
- Anita A Disney
- Center for Neural Science, New York University, 4 Washington Place, New York, NY 10003, USA.
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Rabin LA, Tanapat P, Relkin N. Chapter 1 Cholinergic components of frontal lobe function and dysfunction. Neuropsychology and Behavioral Neurology 2008. [DOI: 10.1016/s0072-9752(07)88001-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Percaccio CR, Pruette AL, Mistry ST, Chen YH, Kilgard MP. Sensory experience determines enrichment-induced plasticity in rat auditory cortex. Brain Res 2007; 1174:76-91. [PMID: 17854780 DOI: 10.1016/j.brainres.2007.07.062] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2007] [Revised: 07/25/2007] [Accepted: 07/31/2007] [Indexed: 10/23/2022]
Abstract
Our previous studies demonstrated that only a few days of housing in an enriched environment increases response strength and paired-pulse depression in the auditory cortex of awake and anesthetized rats [Engineer, N.D., Percaccio, C.R., Pandya, P.K., Moucha, R., Rathbun, D.L., Kilgard, M.P., 2004. Environmental enrichment improves response strength, threshold, selectivity, and latency of auditory cortex neurons. J Neurophysiol. 92, 73-82 and Percaccio, C.R., Engineer, N.D., Pruette, A.L., Pandya, P.K., Moucha, R., Rathbun, D.L., Kilgard, M.P., 2005. Environmental enrichment increases paired-pulse depression in rat auditory cortex. J Neurophysiol. 94, 3590-3600]. Multiple environmental and neurochemical factors likely contribute to the expression of this plasticity. In the current study, we examined the contribution of social stimulation, exercise, auditory exposure, and cholinergic modulation to enrichment-induced plasticity. We recorded epidural evoked potentials from awake rats in response to tone pairs and noise bursts. Auditory evoked responses were not altered by social stimulation or exercise. Rats that could hear the enriched environment, but not interact with it, exhibited enhanced responses to tones and increased paired-pulse depression. The degree to which enrichment increased response strength and forward masking was not reduced after a ventricular injection of 192 IgG-saporin. These results indicate that rich auditory experience stimulates physiological plasticity in the auditory cortex, despite persistent deficits in cholinergic activity. This conclusion may be beneficial to clinical populations with sensory gating and cholinergic abnormalities, including individuals with autism, schizophrenia, and Alzheimer's disease.
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Affiliation(s)
- Cherie R Percaccio
- Neuroscience Program, School of Behavioral and Brain Sciences, GR 41, University of Texas at Dallas, 2601 N. Floyd Road, Richardson, TX 75083-0688, USA.
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McCoy PA, McMahon LL. Muscarinic receptor dependent long-term depression in rat visual cortex is PKC independent but requires ERK1/2 activation and protein synthesis. J Neurophysiol 2007; 98:1862-70. [PMID: 17634336 DOI: 10.1152/jn.00510.2007] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Intact cholinergic innervation of visual cortex is critical for normal processing of visual information and for spatial memory acquisition and retention. However, a complete description of the mechanisms by which the cholinergic system modifies synaptic function in visual cortex is lacking. Previously it was shown that activation of the m1 subtype of muscarinic receptor induces an activity-dependent and partially N-methyl-d-aspartate receptor (NMDAR)-dependent long-term depression (LTD) at layer 4-layer 2/3 synapses in rat visual cortex slices in vitro. The cellular mechanisms downstream of the Galphaq coupled m1 receptor required for induction of this LTD (which we term mLTD) are currently unknown. Here, we confirm a role for m1 receptors in mLTD induction and use a series of pharmacological tools to study the signaling molecules downstream of m1 receptor activation in mLTD induction. We found that mLTD is prevented by inhibitors of L-type Ca(2+) channels, the Src kinase family, and the mitogen-activated kinase/extracellular kinase. mLTD is also partially dependent on phospholipase C but is unaffected by blocking protein kinase C. mLTD expression can be long-lasting (>2 h) and its long-term maintenance requires translation. Thus we report the signaling mechanisms underlying induction of an m1 receptor-dependent LTD in visual cortex and the requirement of protein synthesis for long-term expression. This plasticity could be a mechanism by which the cholinergic system modifies glutamatergic synapse function to permit normal visual system processing required for cognition.
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Affiliation(s)
- Portia A McCoy
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294-0005, USA
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26
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Hasegawa K, Ogawa H. Effects of acetylcholine on coding of taste information in the primary gustatory cortex in rats. Exp Brain Res 2006; 179:97-109. [PMID: 17109107 DOI: 10.1007/s00221-006-0772-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2006] [Accepted: 10/18/2006] [Indexed: 10/23/2022]
Abstract
Acetylcholine (ACh) receptors are widely distributed throughout the cerebral cortex in rats. Recently, cholinergic innervation of the gustatory cortex (GC) was reported to be involved in certain taste learning in rats. Here, the effects of iontophoretic application of ACh on the response properties of GC neurons were studied in urethane-anesthetized rats. ACh affected spontaneous discharges in a small fraction of taste neurons (11 of 86 neurons tested), but influenced taste responses in 27 of 43 neurons tested. No correlations with ACh susceptibility were noted for spontaneous discharges and taste responses. Among the 27 neurons, ACh facilitated taste responses in 13, inhibited taste responses in 13 and either facilitated or inhibited taste responses depending on the stimuli in 1. Furthermore, ACh affected the responses to best stimuli that produced the largest responses among four basic tastants (best responses) in 7 of 27 taste neurons, to non-best responses in 9, and to both best and non-best responses in 11. ACh mostly inhibited the best responses (13 of 18 neurons). Thus, ACh often decreased the response selectivity to the four basic tastants and changed the response profile. Atropine, a general antagonist of muscarinic receptors, antagonized ACh actions on taste responses or displayed the opposite effects on taste responses to ACh actions in two-thirds of the neurons tested. These findings indicate that ACh mostly modulates taste responses through muscarinic receptors, and suggest that ACh shifts the state of the neuron network in the GC, in terms of the response selectivities and response profiles.
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Affiliation(s)
- Kayoko Hasegawa
- Department of Sensory and Cognitive Physiology, Faculty of Medical and Pharmaceutical Sciences, Kumamoto University, Honjo 1-1-1, Kumamoto 860-8556, Japan.
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Yener GG, Güntekin B, Oniz A, Başar E. Increased frontal phase-locking of event-related theta oscillations in Alzheimer patients treated with cholinesterase inhibitors. Int J Psychophysiol 2006; 64:46-52. [PMID: 17011650 DOI: 10.1016/j.ijpsycho.2006.07.006] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2006] [Revised: 06/24/2006] [Accepted: 07/13/2006] [Indexed: 10/24/2022]
Abstract
This is a pilot study describing event-related oscillations in patients with Alzheimer-type dementia (AD). Theta responses of 22 mild probable AD subjects according to NINCDS-ADRDA criteria (11 non-treated, 11 treated by cholinesterase inhibitors), and 20 healthy elderly controls were analyzed by using the conventional visual oddball paradigm. We aimed to compare theta responses of the three groups in a range between 4-7 Hz at the frontal electrodes. At F(3) location, theta responses of healthy subjects were phase locked to stimulation and theta oscillatory responses of non-treated Alzheimer patients showed weaker phase-locking, i.e. average of Z-transformed means of correlation coefficients between single trials was closer to zero. In treated AD patients, phase-locking following target stimulation was two times higher in comparison to the responses of non-treated patients. The results indicate that the phase-locking of theta oscillations at F(3) in the treated patients is as strong as the control subjects. The F(4) theta responses were not statistically significant between the groups. Our findings imply that the theta responses at F(3) location are highly unstable in comparison to F(4) in non-treated mild AD patients and cholinergic agents may modulate event-related theta oscillatory activities in the frontal regions.
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Affiliation(s)
- G G Yener
- Dokuz Eylül University, Faculty of Medicine Departments of Neurology and Neural Sciences, 35340, Izmir, Turkey.
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Zinke W, Roberts MJ, Guo K, McDonald JS, Robertson R, Thiele A. Cholinergic modulation of response properties and orientation tuning of neurons in primary visual cortex of anaesthetized Marmoset monkeys. Eur J Neurosci 2006; 24:314-28. [PMID: 16882027 PMCID: PMC1888486 DOI: 10.1111/j.1460-9568.2006.04882.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Cortical processing is strongly influenced by the actions of neuromodulators such as acetylcholine (ACh). Early studies in anaesthetized cats argued that acetylcholine can cause a sharpening of orientation tuning functions and an improvement of the signal-to-noise ratio (SNR) of neuronal responses in primary visual cortex (V1). Recent in vitro studies have demonstrated that acetylcholine reduces the efficacy of feedback and intracortical connections via the activation of muscarinic receptors, and increases the efficacy of feed-forward connections via the activation of nicotinic receptors. If orientation tuning is mediated or enhanced by intracortical connections, high levels of acetylcholine should diminish orientation tuning. Here we investigate the effects of acetylcholine on orientation tuning and neuronal responsiveness in anaesthetized marmoset monkeys. We found that acetylcholine caused a broadening of the orientation tuning in the majority of cells, while tuning functions became sharper in only a minority of cells. Moreover, acetylcholine generally facilitated neuronal responses, but neither improved signal-to-noise ratio, nor reduced trial-to-trial firing rate variance systematically. Acetylcholine did however, reduce variability of spike occurrences within spike trains. We discuss these findings in the context of dynamic control of feed-forward and lateral/feedback connectivity by acetylcholine.
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Affiliation(s)
- W Zinke
- Psychology, Brain and Behaviour, Henry Wellcome Building, University of Newcastle upon Tyne, Newcastle upon Tyne, NE2 HH, UK
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29
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Abstract
Cholinergic arousal mechanisms predispose thalamic and cortical neurons to fire action potentials at gamma rhythms, which have a tendency to resonate in thalamocortical networks, thereby forming coherent assemblies under constraints of sensory input to specific thalamic nuclei, on the one hand, and prefrontal and limbic attentional mechanisms, on the other. Perception may be based on sustained assemblies of coherent gamma oscillations in thalamocortical circuits. In schizophrenia, the impact of sensory input on self-organization of thalamocortical activity may be generally reduced. As a result, processes underlying perception can become uncoupled from sensory input, particularly at times of hyperarousal, leading to domination of attentional mechanisms and the emergence of hallucinations. Evidence is reviewed that implicates excessive neuronal noise in specific thalamic nuclei in the generation of hallucinations in schizophrenia. Nicotinic receptor abnormalities, dopaminergic hyperactivity and glutamate-receptor hypofunction are reconciled within a model of psychotic symptom generation that places crucial emphasis on dysfunction of the reticular thalamic nucleus.
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Abstract
A continuum from neuronal cellular/subcellular properties to system processes appears to exist in many instances and to allow privileged approaches in neuroscience and neuropharmacology research. Brain signals and the cholinergic and GABAergic systems, in vivo and in vitro evidence from studies on the retina, or the "gamma band" oscillations in neuron membrane potential/spiking rate and neuronal assemblies are examples in this respect. However, spontaneous and stimulus-event-related signals at any location and time point reflect brain state conditions that depend on neuromodulation, neurotransmitter interaction, hormones (e.g., glucocorticois, ACTH, estrogens) and neuroendocrine interaction at different levels of complexity, as well as on the spontaneous or experimentally-induced changes in metabolism (e.g., glucose, ammonia), blood flow, pO2, pCO2, acid/base balance, K activity, etc., that occur locally or systemically. Any of these factors can account for individual differences and/or changes over time that often are (or need to be) neglected in pharmaco-EEG studies or are dealt with statistically and by controlling the experimental conditions. As a result, the electrophysiological effects of neuroactive drugs are to an extent non-specific and require adequate modeling and precise correlation with independent parameters (e.g., drug kinetics, vigilance, hormonal profile or metabolic status, etc.) to avoid biased results in otherwise controlled studies.
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Affiliation(s)
- S Carozzo
- Department of Motor Sciences and Rehabilitation, University of Genova, Genova, Italy
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Tobimatsu S, Celesia GG. Studies of human visual pathophysiology with visual evoked potentials. Clin Neurophysiol 2006; 117:1414-33. [PMID: 16516551 DOI: 10.1016/j.clinph.2006.01.004] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2005] [Revised: 12/28/2005] [Accepted: 01/11/2006] [Indexed: 11/19/2022]
Abstract
Visual evoked potentials (VEPs) offer reproducible and quantitative data on the function of the visual pathways and the visual cortex. Pattern reversal VEPs to full-field stimulation are best suited to evaluate anterior visual pathways while hemi-field stimulation is most effective in the assessment of post-chiasmal function. However, visual information is processed simultaneously via multiple parallel channels and each channel constitutes a set of sequential processes. We outline the major parallel pathways of the visual system from the retina to the primary visual cortex and higher visual areas via lateral geniculate nucleus that receive visual input. There is no best method of stimulus selection, rather visual stimuli and VEPs' recording should be tailored to answer specific clinical and/or research questions. Newly developed techniques that can assess the functions of extrastriate as well as striate cortices are discussed. Finally, an algorithm of sequential steps to evaluate the various levels of visual processing is proposed and its clinical use revisited.
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Affiliation(s)
- Shozo Tobimatsu
- Department of Clinical Neurophysiology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-Ku, Fukuoka 812-8582, Japan.
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Abstract
After dividing clinicians for almost 70 years, Charles Bonnet syndrome has reached an impasse. Defined by a neurologist in the 1930s, the syndrome was intended to eponymize the association of visual hallucinations with age, but evolved into one describing their association with eye disease or, more recently, an etiologically neutral phenomenologic description. Each tradition has its merits but none has defined a specific clinical entity or accounted for visual hallucinations across the spectrum of associated clinical conditions. Recent insights into the neurobiology of vision have shed new light on the problem. Viewed from a neuro-phenomenologic perspective, clinical evidence reveals two distinct hallucination syndromes: one directly related to visual system pathology, the other to pathology in the brainstem or ascending neurotransmitter pathways. The implication is of two independent but interacting pathophysiologic mechanisms and of a need to reassess the classification and management of this common psychopathologic symptom.
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Affiliation(s)
- Dominic H Ffytche
- Centre for Neuroimaging Sciences, Institute of Psychiatry, PO 89 De Crespigny Park, Denmark Hill, London SE5 8AF, United Kingdom.
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Sarter M, Hasselmo ME, Bruno JP, Givens B. Unraveling the attentional functions of cortical cholinergic inputs: interactions between signal-driven and cognitive modulation of signal detection. ACTA ACUST UNITED AC 2005; 48:98-111. [PMID: 15708630 DOI: 10.1016/j.brainresrev.2004.08.006] [Citation(s) in RCA: 479] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2004] [Indexed: 12/17/2022]
Abstract
Neurophysiological studies demonstrated that increases in cholinergic transmission in sensory areas enhance the cortical processing of thalamic inputs. Cholinergic activity also suppresses the retrieval of internal associations, thereby further promoting sensory input processing. Behavioral studies documented the role of cortical cholinergic inputs in attentional functions and capacities by demonstrating, for example, that the integrity of the cortical cholinergic input system is necessary for attentional performance, and that the activity of cortical cholinergic inputs is selectively enhanced during attentional performance. This review aims at integrating the neurophysiological and behavioral evidence on the functions of cortical cholinergic inputs and hypothesizes that the cortical cholinergic input system generally acts to optimize the processing of signals in attention-demanding contexts. Such signals 'recruit', via activation of basal forebrain corticopetal cholinergic projections, the cortical attention systems and thereby amplify the processing of attention-demanding signals (termed 'signal-driven cholinergic modulation of detection'). The activity of corticopetal cholinergic projections is also modulated by direct prefrontal projections to the basal forebrain and, indirectly, to cholinergic terminals elsewhere in the cortex; thus, cortical cholinergic inputs are also involved in the mediation of top-down effects, such as the knowledge-based augmentation of detection (see Footnote 1) of signals and the filtering of irrelevant information (termed 'cognitive cholinergic modulation of detection'). Thus, depending on the quality of signals and task characteristics, cortical cholinergic activity reflects the combined effects of signal-driven and cognitive modulation of detection. This hypothesis begins to explain signal intensity or duration-dependent performance in attention tasks, the distinct effects of cortex-wide versus prefrontal cholinergic deafferentation on attention performance, and it generates specific predictions concerning cortical acetylcholine (ACh) release in attention task-performing animals. Finally, the consequences of abnormalities in the regulation of cortical cholinergic inputs for the manifestation of the symptoms of major neuropsychiatric disorders are conceptualized in terms of dysregulation in the signal-driven and cognitive cholinergic modulation of detection processes.
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Affiliation(s)
- Martin Sarter
- Department of Psychology, University of Michigan, 525 E. University Ave., Ann Arbor, MI 48109-1109, USA.
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Rowe DL, Robinson PA, Gordon E. Stimulant drug action in attention deficit hyperactivity disorder (ADHD): inference of neurophysiological mechanisms via quantitative modelling. Clin Neurophysiol 2005; 116:324-35. [PMID: 15661111 DOI: 10.1016/j.clinph.2004.08.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/02/2004] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To infer the neural mechanisms underlying tonic transitions in the electroencephalogram (EEG) in 11 adolescents diagnosed with attention deficit hyperactivity disorder (ADHD) before and after treatment with stimulant medication. METHODS A biophysical model was used to analyse electroencephalographic (EEG) measures of tonic brain activity at multiple scalp sites before and after treatment with medication. RESULTS It was observed that stimulants had the affect of significantly reducing the parameter controlling activation in the intrathalamic pathway involving the thalamic reticular nucleus (TRN) and the parameter controlling excitatory cortical activity. The effect of stimulant medication was also found to be preferentially localized within subcortical nuclei projecting towards frontal and central scalp sites. CONCLUSIONS It is suggested that the action of stimulant medication occurs via suppression of the locus coeruleus, which in turn reduces stimulation of the TRN, and improves cortical arousal. The effects localized to frontal and central sites are consistent with the occurrence of frontal delta-theta EEG abnormalities in ADHD, and existing theories of hypoarousal. SIGNIFICANCE To our knowledge, this is the first study where a detailed biophysical model of the brain has been used to estimate changes in neurophysiological parameters underlying the effects of stimulant medication in ADHD.
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Affiliation(s)
- D L Rowe
- School of Physics, University of Sydney, Camperdown, NSW 2006, Australia.
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Bentley P, Husain M, Dolan RJ. Effects of cholinergic enhancement on visual stimulation, spatial attention, and spatial working memory. Neuron 2004; 41:969-82. [PMID: 15046728 DOI: 10.1016/s0896-6273(04)00145-x] [Citation(s) in RCA: 134] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2003] [Revised: 01/09/2004] [Accepted: 02/16/2004] [Indexed: 02/03/2023]
Abstract
We compared behavioral and neural effects of cholinergic enhancement between spatial attention, spatial working memory (WM), and visual control tasks, using fMRI and the anticholinesterase physostigmine. Physostigmine speeded responses nonselectively but increased accuracy selectively for attention. Physostigmine also decreased activations to visual stimulation across all tasks within primary visual cortex, increased extrastriate occipital cortex activation selectively during maintained attention and WM encoding, and decreased parietal activation selectively during maintained attention. Finally, lateralization of occipital activation as a function of the visual hemifield toward which attention or memory was directed was decreased under physostigmine. In the case of attention, this effect correlated strongly with a decrease in a behavioral measure of selective spatial processing. Our results suggest that, while cholinergic enhancement facilitates visual attention by increasing activity in extrastriate cortex generally, it accomplishes this in a manner that reduces expectation-driven selective biasing of extrastriate cortex.
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Affiliation(s)
- P Bentley
- Wellcome Department of Imaging Neuroscience, 12 Queen Square, London WC1N 3BG, UK.
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Affiliation(s)
- M Marsel Mesulam
- Cognitive Neurology and Alzheimer's Disease Center, Departments of Neurology and Psychiatry, Feinberg Medical School, Northwestern University, 320 East Superior Street, Chicago, IL 60611, USA.
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37
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Affiliation(s)
- Raju Metherate
- Department of Neurobiology and Behavior, University of California, 2205 McGaugh Hall, Irvine, CA 92697-4450, USA.
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38
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Erisir A, Levey AI, Aoki C. Muscarinic receptor M(2) in cat visual cortex: laminar distribution, relationship to gamma-aminobutyric acidergic neurons, and effect of cingulate lesions. J Comp Neurol 2001; 441:168-85. [PMID: 11745643 DOI: 10.1002/cne.1405] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Acetylcholine can have diverse effects on visual cortical neurons as a result of variations in postsynaptic receptor subtypes as well as the types of neurons and subcellular sites targeted. This study examines the cellular basis for cholinergic activation in visual cortex via M(2) type muscarinic receptors in gamma-aminobutyric acid (GABA)-ergic and non-GABAergic cells, using immunocytochemical techniques. At light microscopic resolution, M(2) immunoreactivity (-ir) was seen in all layers except area and sublayer specific bands in layer 4. Subcellularly, M(2)-ir occurred in both dendrites and terminals that form symmetric and asymmetric junctions. Layers 5 and 6 were characterized by axosomatic contacts that displayed labeling in the presynaptic component, and layer 6 displayed perikaryal postsynaptic staining, suggesting that corticofugal output neurons may be modulated particularly strongly via M(2). Infragranular layers differed from the supragranular layers in that more labeled profiles were axonal than dendritic, indicating a dominant presynaptic effect by acetylcholine via M(2) there. Unilateral cingulate cortex cuts caused reduction of cholinergic and noradrenergic fibers in the lesioned hemisphere at light microscopic resolution; at electron microscopic resolution, the synapse density and axonal M(2) labeling were reduced, suggesting that M(2) was localized presynaptically on extrathalamic modulatory inputs. Dual labeling with GABA in visual cortex layer 5 showed that half of M(2)-labeled dendrites originated from GABAergic neurons. Given that only one-fifth of all cortical dendritic profiles are GABAergic, this prevalence of dual labeling indicates an enrichment of M(2) within GABAergic dendrites and, thus, implicates abundant postsynaptic action on GABAergic neurons via M(2). In contrast, only one-tenth of M(2)-labeled terminals originated from GABAergic neurons, suggesting that the presynaptic action of acetylcholine via M(2) receptors would be more selective for non-GABAergic terminals.
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Affiliation(s)
- A Erisir
- Department of Psychology, University of Virginia, 102 Gilmer Hall, Charlottesville, VA 22904, USA.
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Gerrikagoitia I, García Del Caño G, Martínez-Millán L. Changes of the cholinergic input to the superior colliculus following enucleation in neonatal and adult rats. Brain Res 2001; 898:61-72. [PMID: 11292449 DOI: 10.1016/s0006-8993(01)02142-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The effects of neonatal and adult enucleation on the adult pattern of cholinergic inputs to the rat superior colliculus (SC) was analysed. In the superficial layers immunohistochemical labelling revealed that choline acetyltransferase (ChAT) was predominantly confined to single boutons which were almost continuously distributed throughout the rostrocaudal and lateromedial axes. In these layers a higher density of boutons was observed in the stratum zonale (SZ) and lower stratum griseum superficiale (SGSl) than in the upper stratum griseum superficiale (SGS(u)) and stratum opticum (SO). In intermediate collicular layers ChAT-immunostaining was mainly found in axonal profiles which were arranged in a patchy fashion. Neonatal enucleation caused a drastic increase in bouton density in the SZ, SGS(u) and SGSl. The density of boutons was particularly high in the SGS(u), giving the appearance of an almost homogeneous distribution of boutons from the collicular surface down to the upper limit of SO. Visual deafferentiation at the adult stage was followed by an increase in the bouton density exclusively in the SZ. Neonatal enucleation produced a dorsoventral enlargement of the region containing patches of ChAT staining which was slightly greater following adult deafferentiation. The results described here show that after visual deafferentiation an increase in ChAT innervation to superficial and intermediate collicular layers occurs, providing new information regarding plasticity in the visual system. In view of previous data on cholinergic function in the central nervous system, such an increase could compensate for the loss of retinal excitatory input by facilitating neuronal responses in the SC.
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Affiliation(s)
- I Gerrikagoitia
- Department of Neurosciences, Faculty of Medicine, University of the Basque Country, 48940-Leioa, Bizkaia, Spain
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40
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Abstract
The psychological construct 'sustained attention' describes a fundamental component of attention characterized by the subject's readiness to detect rarely and unpredictably occurring signals over prolonged periods of time. Human imaging studies have demonstrated that activation of frontal and parietal cortical areas, mostly in the right hemisphere, are associated with sustained attention performance. Animal neuroscientific research has focused on cortical afferent systems, particularly on the cholinergic inputs originating in the basal forebrain, as crucial components of the neuronal network mediating sustained attentional performance. Sustained attention performance-associated activation of the basal forebrain corticopetal cholinergic system is conceptualized as a component of the 'top-down' processes initiated by activation of the 'anterior attention system' and designed to mediate knowledge-driven detection and selection of target stimuli. Activated cortical cholinergic inputs facilitate these processes, particularly under taxing attentional conditions, by enhancing cortical sensory and sensory-associational information processing, including the filtering of noise and distractors. Collectively, the findings from human and animal studies provide the basis for a relatively precise description of the neuronal circuits mediating sustained attention, and the dissociation between these circuits and those mediating the 'arousal' components of attention.
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Affiliation(s)
- M Sarter
- Department of Psychology, The Ohio State University, 27 Townshend Hall, Columbus, OH 43210, USA.
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Butt CM, Pauly JR, Wilkins LH, Dwoskin LP, Debski EA. Pharmacology, distribution and development of muscarinic acetylcholine receptor subtypes in the optic tectum of Rana pipiens. Neuroscience 2001; 104:161-79. [PMID: 11311540 PMCID: PMC2266691 DOI: 10.1016/s0306-4522(01)00048-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Visually evoked behaviors mediated by the frog optic tectum require cholinergic activity, but the receptor subtypes through which acetylcholine acts are not yet identified. Using quantitative autoradiography and scintillation spectrometry, we examined the binding of [3H]pirenzepine and [3H]AF-DX 384 in the laminated optic tectum of the frog. In mammalian systems, these substances bind excitatory (m1 and m3 subtypes) and inhibitory (m2 and m4 subtypes) muscarinic acetylcholine receptors, respectively. Pharmacological analyses, including the use of specific muscarinic toxins, confirmed the subtype selectivity of the radioligands in the frog brain. Binding sites for [3H]pirenzepine were distinct from those for [3H]AF-DX 384. In the adult tectum, [3H]pirenzepine demonstrated specific binding in tectal layers 5-9. [3H]Pirenzepine binding was also present in tadpoles as young as stage V, but all sampled stages of tadpole tectum had significantly less binding when compared to adults. Lesioning of the optic nerve had no effect on [3H]pirenzepine binding. Specific [3H]AF-DX 384 binding was found in all layers of the adult tectum. All sampled tadpole stages exhibited binding sites for [3H]AF-DX 384, but the densities of these sites were also significantly higher in adults than they were in developing stages. Short-term lesions of the optic nerve reduced [3H]AF-DX 384 binding in all tectal layers of the deafferented lobe when compared to the afferented one. Long-term lesions decreased [3H]AF-DX 384 sites in both lobes.These results indicate that multiple muscarinic acetylcholine receptor binding sites reside in the frog optic tectum at all stages of development, and their pharmacology resembles that of mammalian m1/m3, m2 and m4 subtypes. Our data indicate that few, if any, of these receptors are likely to be located on retinal ganglion cell terminals. Furthermore, the expression of inhibitory muscarinic subtypes seems to be regulated by different mechanisms than that for excitatory subtypes.
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Affiliation(s)
- C. M. Butt
- School of Biological Sciences, University of Kentucky, 101 T. H. Morgan Building, Lexington, KY 40506-0225, USA
| | - J. R. Pauly
- Division of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40506-0082, USA
| | - L. H. Wilkins
- Division of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40506-0082, USA
| | - L. P. Dwoskin
- Division of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40506-0082, USA
| | - E. A. Debski
- School of Biological Sciences, University of Kentucky, 101 T. H. Morgan Building, Lexington, KY 40506-0225, USA
- Corresponding author. Tel.: +1-859-323-9537; fax: +1-859-257-1717. E-mail address: (E. A. Debski)
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42
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Abstract
This review examines the role of acetylcholine in synaptic plasticity in archi-, paleo- and neocortex. Studies using microiontophoretic application of acetylcholine in vivo and in vitro and electrical stimulation of the basal forebrain have demonstrated that ACh can produce long-lasting increases in neural responsiveness. This evidence comes mainly from models of heterosynaptic facilitation in which acetylcholine produces a strengthening of a second, noncholinergic synaptic input onto the same neuron. The argument that the basal forebrain cholinergic system is essential in some models of plasticity is supported by studies that have selectively lesioned the cholinergic basal forebrain. This review will examine the mechanisms whereby acetylcholine might induce synaptic plasticity. It will also consider the neural circuitry implicated in these studies, namely the pathways that are susceptible to cholinergic plasticity and the neural regulation of the cholinergic system.
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Affiliation(s)
- D D Rasmusson
- Department of Physiology and Biophysics, Dalhousie University, NS, B3H 4H7, Halifax, Canada.
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Abstract
The strength of the McCollough effect (ME), a pattern-contingent colour aftereffect, has been shown to be inversely related to acetylcholine, being significantly strengthened by (anticholinergic) scopolamine and weakened by (cholinergic) physostigmine delivered before adapting to the ME stimuli. The purpose of the present study was (i) to establish whether the effect of pre-adaptation scopolamine is linearly dose-dependent and (ii) to investigate the effects of scopolamine and physostigmine delivered between adaptation and testing. In experiment 1, ten healthy male volunteers who received placebo, or 0.6 mg, 1.2 mg, or 1.8 mg scopolamine before adapting to ME stimuli showed a significant linear dose-dependence over tests repeated from 10 to 70 min after adaptation. In experiment 2 twelve male volunteers adapted to ME stimuli and then received placebo, 1.2 mg oral scopolamine, or 0.75 mg subcutaneous physostigmine. On subsequent repeated testing, strength of the ME was increased by scopolamine and decreased by physostigmine relative to placebo. Both experiments were double-blind double-dummy repeated measures. These data support the view that the ME is a product of inhibitory mechanisms in the visual system rather than processes involved in associative learning.
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Affiliation(s)
- W Byth
- School of Psychology, Queen's University of Belfast, Northern Ireland, UK.
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44
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Abstract
Acetylcholine allows the elicitation of visually evoked behaviors mediated by the frog optic tectum, but the mechanisms behind its effects are unknown. Although nicotinic acetylcholine receptors (nAChRs) exist in the tectum, their subtype has not been assessed. By using quantitative autoradiography, we examined the binding of [(3)H]cytisine and [(125)I]alpha-bungarotoxin in the laminated tectum. In mammalian systems, these radioligands bind with high affinity to alpha4 nAChR subunits and alpha7 nAChR subunits, respectively. [(3)H]Cytisine demonstrated high specific binding in adult frogs in retinorecipient layer 9, intermediate densities in layer 8, and low binding in layers 1-7 of the tectum. [(3)H]Cytisine binding was significantly higher in the tecta of adults than in those of tadpoles. Lesioning the optic nerve for 6 weeks decreased [(3)H]cytisine binding in layers 8/9 by 70+/-1%, whereas 6-month lesions decreased binding by 76+/-3%. Specific binding of [(125)I]alpha-bungarotoxin in adults was present only at intermediate levels in tectal layers 8 and 9, and undetectable in the deeper tectal layers. However, the nucleus isthmi, a midbrain structure reciprocally connected to the tectum, exhibited high levels of binding. There were no significant differences in tectal [(125)I]alpha-bungarotoxin binding between tadpoles and adults. Six-week lesions of the optic nerve decreased tectal [(125)I]alpha-bungarotoxin binding by 33+/-10%, but 6-month lesions had no effect. The pharmacokinetic characteristics of [(3)H]cytisine and [(125)I]alpha-bungarotoxin binding in the frog brain were similar to those demonstrated in several mammalian species. These results indicate that [(3)H]cytisine and [(125)I]alpha-bungarotoxin identify distinct nAChR subtypes in the tectum that likely contain non-alpha7 and alpha7 subunits, respectively. The majority of non-alpha7 receptors are likely associated with retinal ganglion cell terminals, whereas alpha7-containing receptors appear to have a different localization.
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Affiliation(s)
- Christopher M. Butt
- School of Biological Sciences, University of Kentucky, Lexington, Kentucky 40506-0225
| | - James R. Pauly
- Division of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40506-0082
| | - Elizabeth A. Debski
- School of Biological Sciences, University of Kentucky, Lexington, Kentucky 40506-0225
- Correspondence to: Dr. Elizabeth A. Debski, School of Biological Sciences, 101 T.H. Morgan Building, University of Kentucky, Lexington, KY 40506-0225. E-mail:
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45
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Abstract
The purpose of these experiments was to determine the effects of cholinergic depletion on spontaneous and evoked activity of neurons in the different layers of the posteromedial barrel subfield (PMBSF) of the rat somatosensory cortex. Acetylcholine neurons in nucleus basalis of Meynert (NBM) were selectively lesioned with an immunotoxin (IT), 192 IgG-saporin. Spontaneous activity was significantly lower in layers II-III, Va, and VI in IT-injected animals compared to control animals. Evoked activity was significantly lower in layers II-III, IV, Vb, and VI of IT-injected animals compared to control animals. The largest difference was observed in layer Vb. Thus, cholinergic depletion causes significant changes in the magnitude of spontaneous and evoked activity but these differences are not completely in register with one another.
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Affiliation(s)
- P Herron
- Departments of Anatomy and Neurobiology, College of Medicine, The University of Tennessee, Memphis, 855 Monroe Avenue, Memphis, TN 38163, USA.
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46
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Abstract
OBJECTIVES To review the coherent, rhythmic oscillations above approximately 20 Hz that occur in response to sensory inputs in the firing rate and membrane or local field potentials of distributed neuron aggregates of CNS layered structures. RESULTS Oscillatory activity at approximately 20-80 Hz occurs in response to either olfactory, auditory and visual (contrast) stimuli; oscillations at frequencies centered on 100-120 Hz or 600 Hz are recorded, respectively, from the visual system (luminance stimulation) and from the somatosensory cortex. Experimental evidence suggests sources/mechanisms of generation that depend on inhibitory interneurons and pyramidal cells and are partially independent from those of conventional (broadband) evoked responses. In the olfactory and visual systems, the oscillatory responses reflect the global stimulus properties. A time/phase correlation between firing rate, spiking coincidence and oscillatory field responses has been documented. The oscillatory responses are postsynaptic both in cortex and in precortical structures (e.g. retina; LGN). Evidence indicates intracortical and thalamocortical interacting mechanisms of regulation as well as GABAergic and cholinergic modulation. In the visual cortex the oscillatory responses are driven by oscillations in the synaptic input. Oscillatory potentials are dependent on resonance phenomena and produce narrow-band synchronization of activated neurons. They may have a role in the 'binding' of separate neuronal aggregates into sensory units. CONCLUSIONS Oscillatory responses contribute as a time/frequency coding mechanism to pacing neurons selectively for the physical properties of stimulus and are involved in sensory information processing.
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Affiliation(s)
- W G Sannita
- Center for Neuroactive Drugs, DISMR University, 16132, Genova, Italy.
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47
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Sarter M, Bruno JP. Cortical cholinergic inputs mediating arousal, attentional processing and dreaming: differential afferent regulation of the basal forebrain by telencephalic and brainstem afferents. Neuroscience 2000; 95:933-52. [PMID: 10682701 DOI: 10.1016/s0306-4522(99)00487-x] [Citation(s) in RCA: 270] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Basal forebrain corticopetal neurons participate in the mediation of arousal, specific attentional functions and rapid eye movement sleep-associated dreaming. Recent studies on the afferent regulation of basal forebrain neurons by telencephalic and brainstem inputs have provided the basis for hypotheses which, collectively, propose that the involvement of basal forebrain corticopetal projections in arousal, attention and dreaming can be dissociated on the basis of their regulation via major afferent projections. While the processing underlying sustained, selective and divided attention performance depends on the integrity of the telencephalic afferent regulation of basal forebrain corticopetal neurons, arousal-induced attentional processing (i.e. stimulus detection, selection and processing as a result of a novel, highly salient, aversive or incentive stimuli) is mediated via the ability of brainstem ascending noradrenergic projections to the basal forebrain to activate or "recruit" these telencephalic afferent circuits of the basal forebrain. In rapid eye movement sleep, both the basal forebrain and thalamic cortiocopetal projections are stimulated by cholinergic afferents originating mainly from the pedunculopontine and laterodorsal tegmenta in the brainstem. Rapid eye movement sleep-associated dreaming is described as a form of hyperattentional processing, mediated by increased activity of cortical cholinergic inputs and their cortical interactions with activated thalamic efferents. In this context, long-standing speculations about the similarities between dreaming and psychotic cognition are substantiated by describing the role of an over(re)active cortical cholinergic input system in either condition. Finally, while determination of the afferent regulation of basal forebrain corticopetal neurons in different behavioral/cognitive states assists in defining the general cognitive functions of cortical acetylcholine, this research requires a specification of the precise anatomical organization of basal forebrain afferents and their interactions in the basal forebrain. Furthermore, the present hypotheses remain incomplete because of the paucity of data concerning the regulation and role of basal forebrain non-cholinergic, particularly GABAergic, efferents.
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Affiliation(s)
- M Sarter
- Department of Psychology, The Ohio State University, Columbus 43210, USA.
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48
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Abstract
Degeneration of cholinergic neurons in the basal forebrain is a neural marker of Alzheimer's disease and is associated with perceptual and cognitive deficits. An idea that has attracted scientific scutiny is that aging makes the brain more susceptible to neurodegenerative diseases such as Alzheimer's. The purpose of this study was to compare the effects of the loss of cholinergic input from nucleus basalis of Meynert on evoked activity in the posteromedial barrel subfield of the somatosensory cortex in young (2-2.5 months) and aged (28-30 months) male Fisher hybrid rats. The mean firing rate and receptive fields of single neurons in the posteromedial barrel subfield of the somatosensory cortex were examined after selective lesions of cholinergic neurons in the nucleus basalis of Meynert with an immunotoxin. IgG 192-saporin. Functional properties of single neurons in young animals were affected much more significantly by cholinergic depletion than those in aged animals. In cholinergic-depleted young animals, the mean firing rate of evoked activity and receptive field of posteromedial barrel subfield neurons were significantly decreased. Cholinergic depletion caused a 14% decrease in evoked activity and a 33% increase in receptive field size in young animals. The mean firing rate and receptive field of single neurons were not affected by cholinergic depletion in aged animals. It is concluded that functional properties of cortical sensory neurons in young animals are more vulnerable to cholinergic depletion than are those of aged animals and that cholinergic depletion does not further impact the properties of neurons exposed to the processes of aging.
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Affiliation(s)
- P Herron
- Department of Anatomy and Neurobiology, College of Medicine, University of Tennessee, Memphis 38163, USA.
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49
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Abstract
Generalized non-convulsive absence seizures are characterized by the occurrence of synchronous and bilateral spike and wave discharges (SWDs) on the electroencephalogram, that are concomitant with a behavioral arrest. Many similarities between rodent and human absence seizures support the use of genetic rodent models, in which spontaneous SWDs occur. This review summarizes data obtained on the neurophysiological and neurochemical mechanisms of absence seizures with special emphasis on the Genetic Absence Epilepsy Rats from Strasbourg (GAERS). EEG recordings from various brain regions and lesion experiments showed that the cortex, the reticular nucleus and the relay nuclei of the thalamus play a predominant role in the development of SWDs. Neither the cortex, nor the thalamus alone can sustain SWDs, indicating that both structures are intimely involved in the genesis of SWDs. Pharmacological data confirmed that both inhibitory and excitatory neurotransmissions are involved in the genesis and control of absence seizures. Whether the generation of SWDs is the result of an excessive cortical excitability, due to an unbalance between inhibition and excitation, or excessive thalamic oscillations, due to abnormal intrinsic neuronal properties under the control of inhibitory GABAergic mechanisms, remains controversial. The thalamo-cortical activity is regulated by several monoaminergic and cholinergic projections. An alteration of the activity of these different ascending inputs may induce a temporary inadequation of the functional state between the cortex and the thalamus and thus promote SWDs. The experimental data are discussed in view of these possible pathophysiological mechanisms.
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Affiliation(s)
- L Danober
- INSERM U 398, Neurobiologie et Neuropharmacologie des épilepsies généralisées, Faculté de Médecine, Strasbourg, France.
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50
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Abstract
Electrophysiological evidence at a cellular level and in vivo macroelectrode recordings converge in indicating a degree of specificity of acetylcholine action in vision. Acetylcholine (ACh) function is also thought to play a significant role in memory, learning and other cognitive processes. In this respect, ACh action is suggested to serve in both sensory and cognitive processes. The pharmacological blocking of brain muscarinic transmission has been proposed as a model of geriatric memory impairment and Alzheimer's dementia. Visual electrophysiological testing is deemed of diagnostic specificity for this disease. ACh brain neurotransmission, however, mostly contributes to the modulation of nonspecific aspects of cognition, such as arousal or attention. Alzheimer's dementia results from complex neuron alterations [which also affect muscarinic receptors among other (sub)cellular structures] rather than simply reflecting ACh impoverishment. A substantial loss of retinal ganglion cells is documented in patients with Alzheimer's disease and is consistent with electrophysiological observations. However, it is unclear to what extent the dysfunction of the visual system observable in Alzheimer's dementia is qualitatively different from that occurring spontaneously during aging. The dissimilarities between the effect of acute muscarinic blocking (e.g. by scopolamine) and dementia outnumber the similarities. Accordingly, the conventional ACh agonist-antagonist model of dementia now appears questionable, and replacement treatment with compounds enhancing ACh function proved disappointing. It is suggested that (nonspecific) ACh action becomes function-specific, as determined by the architecture of local brain circuits in which it is involved.
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Affiliation(s)
- L Nobili
- Department of Motor Sciences and Rehabilitation-Neurophysiopathology, University of Genoa, Italy
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