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Sadacca BF, Wikenheiser AM, Schoenbaum G. Toward a theoretical role for tonic norepinephrine in the orbitofrontal cortex in facilitating flexible learning. Neuroscience 2016; 345:124-129. [PMID: 27102419 DOI: 10.1016/j.neuroscience.2016.04.017] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 04/08/2016] [Accepted: 04/11/2016] [Indexed: 10/21/2022]
Abstract
To adaptively respond in a complex, changing world, animals need to flexibly update their understanding of the world when their expectations are violated. Though several brain regions in rodents and primates have been implicated in aspects of this updating, current models of orbitofrontal cortex (OFC) and norepinephrine neurons of the locus coeruleus (LC-NE) suggest that each plays a role in responding to environmental change, where the OFC allows updating of prior learning to occur without overwriting or unlearning one's previous understanding of the world that changed, while elevated tonic NE allows for increased flexibility in behavior that tracks an animal's uncertainty. In light of recent studies highlighting a specific LC-NE projection to the OFC, in this review we discuss current models of OFC and NE function, and their potential synergy in the updating of associations following environmental change.
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Affiliation(s)
- Brian F Sadacca
- Intramural Research Program of the National Institute on Drug Abuse, NIH, United States.
| | - Andrew M Wikenheiser
- Intramural Research Program of the National Institute on Drug Abuse, NIH, United States
| | - Geoffrey Schoenbaum
- Intramural Research Program of the National Institute on Drug Abuse, NIH, United States; Department of Anatomy and Neurobiology, University of Maryland School of Medicine, United States; Department of Neuroscience, Johns Hopkins School of Medicine, United States.
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Novitskaya Y, Sara SJ, Logothetis NK, Eschenko O. Ripple-triggered stimulation of the locus coeruleus during post-learning sleep disrupts ripple/spindle coupling and impairs memory consolidation. ACTA ACUST UNITED AC 2016; 23:238-48. [PMID: 27084931 PMCID: PMC4836638 DOI: 10.1101/lm.040923.115] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 02/28/2016] [Indexed: 11/25/2022]
Abstract
Experience-induced replay of neuronal ensembles occurs during hippocampal high-frequency oscillations, or ripples. Post-learning increase in ripple rate is predictive of memory recall, while ripple disruption impairs learning. Ripples may thus present a fundamental component of a neurophysiological mechanism of memory consolidation. In addition to system-level local and cross-regional interactions, a consolidation mechanism involves stabilization of memory representations at the synaptic level. Synaptic plasticity within experience-activated neuronal networks is facilitated by noradrenaline release from the axon terminals of the locus coeruleus (LC). Here, to better understand interactions between the system and synaptic mechanisms underlying “off-line” consolidation, we examined the effects of ripple-associated LC activation on hippocampal and cortical activity and on spatial memory. Rats were trained on a radial maze; after each daily learning session neural activity was monitored for 1 h via implanted electrode arrays. Immediately following “on-line” detection of ripple, a brief train of electrical pulses (0.05 mA) was applied to LC. Low-frequency (20 Hz) stimulation had no effect on spatial learning, while higher-frequency (100 Hz) trains transiently blocked generation of ripple-associated cortical spindles and caused a reference memory deficit. Suppression of synchronous ripple/spindle events appears to interfere with hippocampal-cortical communication, thereby reducing the efficiency of “off-line” memory consolidation.
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Affiliation(s)
- Yulia Novitskaya
- Max Planck Institute for Biological Cybernetics, Tubingen 72076, Germany
| | - Susan J Sara
- Center for Integrative Research in Biology, CNRS-UMR7152, Collège de France, Paris 75005, France Department of Child and Adolescent Psychiatry, New York University Medical School, New York, New York 10016, USA
| | - Nikos K Logothetis
- Max Planck Institute for Biological Cybernetics, Tubingen 72076, Germany Centre for Imaging Sciences, Biomedical Imaging Institute, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Oxana Eschenko
- Max Planck Institute for Biological Cybernetics, Tubingen 72076, Germany
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53
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Zamzow RM, Ferguson BJ, Stichter JP, Porges EC, Ragsdale AS, Lewis ML, Beversdorf DQ. Effects of propranolol on conversational reciprocity in autism spectrum disorder: a pilot, double-blind, single-dose psychopharmacological challenge study. Psychopharmacology (Berl) 2016; 233:1171-8. [PMID: 26762378 DOI: 10.1007/s00213-015-4199-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 12/21/2015] [Indexed: 10/22/2022]
Abstract
RATIONALE Pharmacological intervention for autism spectrum disorder (ASD) is an important addition to treatment, yet currently available agents target co-morbid psychiatric concerns, such as aggression and irritability. Propranolol, a beta-adrenergic antagonist with anxiolytic effects, has been shown to improve verbal fluency and working memory in adults and adolescents with ASD in single-dose challenges. OBJECTIVES The present pilot study explores the acute effects of propranolol on a measure of conversational reciprocity in this population. We also examined whether autonomic activity and anxiety moderate or mediate response to the drug, given relationships between these variables and ASD, as well as the drug's effects. METHODS In a within-subject crossover design, 20 individuals with ASD received a single dose of propranolol or placebo during two sessions in a double-blinded, counterbalanced manner. After drug administration, participants performed a conversational reciprocity task by engaging in a short conversation with the researcher. Measurements of autonomic activity and anxiety were obtained before and after drug administration. RESULTS Propranolol significantly improved performance on the conversational reciprocity task total [d = 0.40] and nonverbal communication domain scores when compared to the placebo condition. However, neither autonomic activity nor anxiety was significantly associated with drug response. CONCLUSIONS Acute propranolol administration improved conversational reciprocity in ASD. Further exploration of these preliminary findings, as well as other potential treatment response predictors, with serial doses is warranted.
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Affiliation(s)
- Rachel M Zamzow
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, USA
| | - Bradley J Ferguson
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, USA
| | - Janine P Stichter
- Department of Special Education, University of Missouri, Columbia, MO, USA
| | - Eric C Porges
- Center for Cognitive Aging and Memory (CAM), Institute on Aging, McKnight Brain Institute, Department of Aging and Geriatric Research, University of Florida, Gainesville, FL, 32608, USA
| | | | - Morgan L Lewis
- Department of Biological Sciences, University of Missouri, Columbia, MO, USA
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA
| | - David Q Beversdorf
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA.
- William and Nancy Thompson Endowed Chair in Radiology, Departments of Radiology and Neurology, and the Thompson Center for Autism and Neurodevelopmental Disorders, University of Missouri, Columbia, MO, USA.
- Department of Radiology, DC069.10, University of Missouri Health Care, One Hospital Dr, Columbia, MO, 65212, USA.
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54
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Heilman KM. Possible Brain Mechanisms of Creativity. Arch Clin Neuropsychol 2016; 31:285-96. [DOI: 10.1093/arclin/acw009] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/26/2016] [Indexed: 11/13/2022] Open
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Dietary Restriction Affects Neuronal Response Property and GABA Synthesis in the Primary Visual Cortex. PLoS One 2016; 11:e0149004. [PMID: 26863207 PMCID: PMC4749323 DOI: 10.1371/journal.pone.0149004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 01/25/2016] [Indexed: 12/02/2022] Open
Abstract
Previous studies have reported inconsistent effects of dietary restriction (DR) on cortical inhibition. To clarify this issue, we examined the response properties of neurons in the primary visual cortex (V1) of DR and control groups of cats using in vivo extracellular single-unit recording techniques, and assessed the synthesis of inhibitory neurotransmitter GABA in the V1 of cats from both groups using immunohistochemical and Western blot techniques. Our results showed that the response of V1 neurons to visual stimuli was significantly modified by DR, as indicated by an enhanced selectivity for stimulus orientations and motion directions, decreased visually-evoked response, lowered spontaneous activity and increased signal-to-noise ratio in DR cats relative to control cats. Further, it was shown that, accompanied with these changes of neuronal responsiveness, GABA immunoreactivity and the expression of a key GABA-synthesizing enzyme GAD67 in the V1 were significantly increased by DR. These results demonstrate that DR may retard brain aging by increasing the intracortical inhibition effect and improve the function of visual cortical neurons in visual information processing. This DR-induced elevation of cortical inhibition may favor the brain in modulating energy expenditure based on food availability.
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Salgado H, Treviño M, Atzori M. Layer- and area-specific actions of norepinephrine on cortical synaptic transmission. Brain Res 2016; 1641:163-76. [PMID: 26820639 DOI: 10.1016/j.brainres.2016.01.033] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 01/08/2016] [Accepted: 01/20/2016] [Indexed: 12/20/2022]
Abstract
The cerebral cortex is a critical target of the central noradrenergic system. The importance of norepinephrine (NE) in the regulation of cortical activity is underscored by clinical findings that involve this catecholamine and its receptor subtypes in the regulation of a large number of emotional and cognitive functions and illnesses. In this review, we highlight diverse effects of the LC/NE system in the mammalian cortex. Indeed, electrophysiological, pharmacological, and behavioral studies in the last few decades reveal that NE elicits a mixed repertoire of excitatory, inhibitory, and biphasic effects on the firing activity and transmitter release of cortical neurons. At the intrinsic cellular level, NE can produce a series of effects similar to those elicited by other monoamines or acetylcholine, associated with systemic arousal. At the synaptic level, NE induces numerous acute changes in synaptic function, and ׳gates' the induction of long-term plasticity of glutamatergic synapses, consisting in an enhancement of engaged and relevant cortical synapses and/or depression of unengaged synapses. Equally important in shaping cortical function, in many cortical areas NE promotes a characteristic, most often reversible, increase in the gain of local inhibitory synapses, whose extent and temporal properties vary between different areas and sometimes even between cortical layers of the same area. While we are still a long way from a comprehensive theory of the function of the LC/NE system, its cellular, synaptic, and plastic effects are consistent with the hypothesis that noradrenergic modulation is critical in coordinating the activity of cortical and subcortical circuits for the integration of sensory activity and working memory. This article is part of a Special Issue entitled SI: Noradrenergic System.
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Affiliation(s)
| | | | - Marco Atzori
- Universidad Autónoma de San Luis Potosí, México.
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57
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Arc-Expressing Neuronal Ensembles Supporting Pattern Separation Require Adrenergic Activity in Anterior Piriform Cortex: An Exploration of Neural Constraints on Learning. J Neurosci 2016; 35:14070-5. [PMID: 26468206 DOI: 10.1523/jneurosci.2690-15.2015] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Arc ensembles in adult rat olfactory bulb (OB) and anterior piriform cortex (PC) were assessed after discrimination training on highly similar odor pairs. Nonselective α- and β-adrenergic antagonists or saline were infused in the OB or anterior PC during training. OB adrenergic blockade slowed, but did not prevent, odor discrimination learning. After criterion performance, Arc ensembles in anterior piriform showed enhanced stability for the rewarded odor and pattern separation for the discriminated odors as described previously. Anterior piriform adrenergic blockade prevented acquisition of similar odor discrimination and of OB ensemble changes, even with extended overtraining. Mitral and granule cell Arc ensembles in OB showed enhanced stability for rewarded odor only in the saline group. Pattern separation was not seen in the OB. Similar odor discrimination co-occurs with increased stability in rewarded odor representations and pattern separation to reduce encoding overlap. The difficulty of similar discriminations may relate to the necessity to both strengthen rewarded representations and weaken overlap across similar representations. SIGNIFICANCE STATEMENT We show for the first time that adrenoceptors in anterior piriform cortex (aPC) must be engaged for adult rats to learn to discriminate highly similar odors. Loss of adrenergic activation in olfactory bulb (OB) slows, but does not prevent, discrimination learning. Both increased stability of the rewarded odor representation and increased pattern separation of the rewarded and unrewarded odors in aPC accompany successful discrimination. In the OB, rewarded odors increase in ensemble stability, but there is no evidence of pattern separation. We suggest that the slow acquisition of similar odor discriminations is related to the differing plasticity requirements for increased stability and pattern separation.
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58
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Ghosh A, Purchase NC, Chen X, Yuan Q. Norepinephrine Modulates Pyramidal Cell Synaptic Properties in the Anterior Piriform Cortex of Mice: Age-Dependent Effects of β-adrenoceptors. Front Cell Neurosci 2015; 9:450. [PMID: 26635530 PMCID: PMC4652601 DOI: 10.3389/fncel.2015.00450] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 11/02/2015] [Indexed: 12/31/2022] Open
Abstract
Early odor preference learning in rodents occurs within a sensitive period [≤postnatal day (P)10–12], during which pups show a heightened ability to form an odor preference when a novel odor is paired with a tactile stimulation (e.g., stroking). Norepinephrine (NE) release from the locus coeruleus during stroking mediates this learning. However, in older pups, stroking loses its ability to induce learning. The cellular and circuitry mechanisms underpinning the sensitive period for odor preference learning is not well understood. We first established the sensitive period learning model in mice – odor paired with stroking induced odor preference in P8 but not P14 mice. This learning was dependent on NE-β-adrenoceptors as it was prevented by propranolol injection prior to training. We then tested whether there are developmental changes in pyramidal cell excitability and NE responsiveness in the anterior piriform cortex (aPC) in mouse pups. Although significant differences of pyramidal cell intrinsic properties were found in two age groups (P8–11 and P14+), NE at two concentrations (0.1 and 10 μM) did not alter intrinsic properties in either group. In contrast, in P8–11 pups, NE at 0.1 μM presynaptically decreased miniature IPSC and increased miniature EPSC frequencies. These effects were reversed with a higher dose of NE (10 μM), suggesting involvement of different adrenoceptor subtypes. In P14+ pups, NE at higher doses (1 and 10 μM) acted both pre- and postsynaptically to promote inhibition. These results suggest that enhanced synaptic excitation and reduced inhibition by NE in the aPC network may underlie the sensitive period.
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Affiliation(s)
- Abhinaba Ghosh
- Division of BioMedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John's NL, Canada
| | - Nicole C Purchase
- Division of BioMedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John's NL, Canada
| | - Xihua Chen
- Division of BioMedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John's NL, Canada
| | - Qi Yuan
- Division of BioMedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John's NL, Canada
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59
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Hutchison IC, Rathore S. The role of REM sleep theta activity in emotional memory. Front Psychol 2015; 6:1439. [PMID: 26483709 PMCID: PMC4589642 DOI: 10.3389/fpsyg.2015.01439] [Citation(s) in RCA: 120] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Accepted: 09/09/2015] [Indexed: 01/18/2023] Open
Abstract
While non-REM (NREM) sleep has been strongly implicated in the reactivation and consolidation of memory traces, the role of rapid-eye movement (REM) sleep remains unclear. A growing body of research on humans and animals provide behavioral evidence for a role of REM sleep in the strengthening and modulation of emotional memories. Theta activity-which describes low frequency oscillations in the local field potential within the hippocampus, amygdala and neocortex-is a prominent feature of both wake and REM sleep in humans and rodents. Theta coherence between the hippocampus and amygdala drives large-scale pontine-geniculo-occipital (PGO) waves, the density of which predicts increases in plasticity-related gene expression. This could potentially facilitate the processing of emotional memory traces within the hippocampus during REM sleep. Further, the timing of hippocampal activity in relation to theta phase is vital in determining subsequent potentiation of neuronal activity. This could allow the emotionally modulated strengthening of novel and gradual weakening of consolidated hippocampal memory traces during REM sleep. Hippocampal theta activity is also correlated with REM sleep levels of achetylcholine - which is thought to reduce hippocampal inputs in the neocortex. The additional low levels of noradrenaline during REM sleep, which facilitate feedback within the neocortex, could allow the integration of novel memory traces previously consolidated during NREM sleep. We therefore propose that REM sleep mediates the prioritized processing of emotional memories within the hippocampus, the integration of previously consolidated memory traces within the neocortex, as well as the disengagement of consolidated neocortical memory traces from the hippocampus.
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Affiliation(s)
- Isabel C Hutchison
- School of Psychological Sciences, Faculty of Medical and Human Sciences, University of Manchester , Manchester, UK
| | - Shailendra Rathore
- Neuroscience, Physiology and Pharmacology, University College London , London, UK ; Centre of Mathematics and Physics in the Life Sciences and Experimental Biology, University College London , London, UK
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60
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Looijestijn J, Blom JD, Aleman A, Hoek HW, Goekoop R. An integrated network model of psychotic symptoms. Neurosci Biobehav Rev 2015; 59:238-50. [PMID: 26432501 DOI: 10.1016/j.neubiorev.2015.09.016] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 09/27/2015] [Indexed: 12/29/2022]
Abstract
The full body of research on the nature of psychosis and its determinants indicates that a considerable number of factors are relevant to the development of hallucinations, delusions, and other positive symptoms, ranging from neurodevelopmental parameters and altered connectivity of brain regions to impaired cognitive functioning and social factors. We aimed to integrate these factors in a single mathematical model based on network theory. At the microscopic level this model explains positive symptoms of psychosis in terms of experiential equivalents of robust, high-frequency attractor states of neural networks. At the mesoscopic level it explains them in relation to global brain states, and at the macroscopic level in relation to social-network structures and dynamics. Due to the scale-free nature of biological networks, all three levels are governed by the same general laws, thereby allowing for an integrated model of biological, psychological, and social phenomena involved in the mediation of positive symptoms of psychosis. This integrated network model of psychotic symptoms (INMOPS) is described together with various possibilities for application in clinical practice.
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Affiliation(s)
- Jasper Looijestijn
- Parnassia Psychiatric Institute, Kiwistraat 43, The Hague 2552 DH, The Netherlands
| | - Jan Dirk Blom
- Parnassia Psychiatric Institute, Kiwistraat 43, The Hague 2552 DH, The Netherlands; Department of Psychiatry, University Medical Center Groningen, University of Groningen, Hanzeplein 1, Groningen 9713 GZ, The Netherlands
| | - André Aleman
- Department of Neuroscience, University Medical Center Groningen, University of Groningen, Antonius Deusinglaan 1, Groningen 9713 AV, The Netherlands
| | - Hans W Hoek
- Parnassia Psychiatric Institute, Kiwistraat 43, The Hague 2552 DH, The Netherlands; Department of Psychiatry, University Medical Center Groningen, University of Groningen, Hanzeplein 1, Groningen 9713 GZ, The Netherlands; Department of Epidemiology, Columbia University, 722 West 168th St., New York, NY, USA
| | - Rutger Goekoop
- Parnassia Psychiatric Institute, Kiwistraat 43, The Hague 2552 DH, The Netherlands.
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61
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Norepinephrine Modulates Coding of Complex Vocalizations in the Songbird Auditory Cortex Independent of Local Neuroestrogen Synthesis. J Neurosci 2015; 35:9356-68. [PMID: 26109659 DOI: 10.1523/jneurosci.4445-14.2015] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The catecholamine norepinephrine plays a significant role in auditory processing. Most studies to date have examined the effects of norepinephrine on the neuronal response to relatively simple stimuli, such as tones and calls. It is less clear how norepinephrine shapes the detection of complex syntactical sounds, as well as the coding properties of sensory neurons. Songbirds provide an opportunity to understand how auditory neurons encode complex, learned vocalizations, and the potential role of norepinephrine in modulating the neuronal computations for acoustic communication. Here, we infused norepinephrine into the zebra finch auditory cortex and performed extracellular recordings to study the modulation of song representations in single neurons. Consistent with its proposed role in enhancing signal detection, norepinephrine decreased spontaneous activity and firing during stimuli, yet it significantly enhanced the auditory signal-to-noise ratio. These effects were all mimicked by clonidine, an α-2 receptor agonist. Moreover, a pattern classifier analysis indicated that norepinephrine enhanced the ability of single neurons to accurately encode complex auditory stimuli. Because neuroestrogens are also known to enhance auditory processing in the songbird brain, we tested the hypothesis that norepinephrine actions depend on local estrogen synthesis. Neither norepinephrine nor adrenergic receptor antagonist infusion into the auditory cortex had detectable effects on local estradiol levels. Moreover, pretreatment with fadrozole, a specific aromatase inhibitor, did not block norepinephrine's neuromodulatory effects. Together, these findings indicate that norepinephrine enhances signal detection and information encoding for complex auditory stimuli by suppressing spontaneous "noise" activity and that these actions are independent of local neuroestrogen synthesis.
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62
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Norepinephrine ignites local hotspots of neuronal excitation: How arousal amplifies selectivity in perception and memory. Behav Brain Sci 2015; 39:e200. [PMID: 26126507 DOI: 10.1017/s0140525x15000667] [Citation(s) in RCA: 328] [Impact Index Per Article: 36.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Emotional arousal enhances perception and memory of high-priority information but impairs processing of other information. Here, we propose that, under arousal, local glutamate levels signal the current strength of a representation and interact with norepinephrine (NE) to enhance high priority representations and out-compete or suppress lower priority representations. In our "glutamate amplifies noradrenergic effects" (GANE) model, high glutamate at the site of prioritized representations increases local NE release from the locus coeruleus (LC) to generate "NE hotspots." At these NE hotspots, local glutamate and NE release are mutually enhancing and amplify activation of prioritized representations. In contrast, arousal-induced LC activity inhibits less active representations via two mechanisms: 1) Where there are hotspots, lateral inhibition is amplified; 2) Where no hotspots emerge, NE levels are only high enough to activate low-threshold inhibitory adrenoreceptors. Thus, LC activation promotes a few hotspots of excitation in the context of widespread suppression, enhancing high priority representations while suppressing the rest. Hotspots also help synchronize oscillations across neural ensembles transmitting high-priority information. Furthermore, brain structures that detect stimulus priority interact with phasic NE release to preferentially route such information through large-scale functional brain networks. A surge of NE before, during, or after encoding enhances synaptic plasticity at NE hotspots, triggering local protein synthesis processes that enhance selective memory consolidation. Together, these noradrenergic mechanisms promote selective attention and memory under arousal. GANE not only reconciles apparently contradictory findings in the emotion-cognition literature but also extends previous influential theories of LC neuromodulation by proposing specific mechanisms for how LC-NE activity increases neural gain.
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63
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de Almeida L, Reiner SJ, Ennis M, Linster C. Computational modeling suggests distinct, location-specific function of norepinephrine in olfactory bulb and piriform cortex. Front Comput Neurosci 2015; 9:73. [PMID: 26136678 PMCID: PMC4468384 DOI: 10.3389/fncom.2015.00073] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2015] [Accepted: 05/27/2015] [Indexed: 12/02/2022] Open
Abstract
Noradrenergic modulation from the locus coerulus is often associated with the regulation of sensory signal-to-noise ratio. In the olfactory system, noradrenergic modulation affects both bulbar and cortical processing, and has been shown to modulate the detection of low concentration stimuli. We here implemented a computational model of the olfactory bulb and piriform cortex, based on known experimental results, to explore how noradrenergic modulation in the olfactory bulb and piriform cortex interact to regulate odor processing. We show that as predicted by behavioral experiments in our lab, norepinephrine can play a critical role in modulating the detection and associative learning of very low odor concentrations. Our simulations show that bulbar norepinephrine serves to pre-process odor representations to facilitate cortical learning, but not recall. We observe the typical non-uniform dose—response functions described for norepinephrine modulation and show that these are imposed mainly by bulbar, but not cortical processing.
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Affiliation(s)
- Licurgo de Almeida
- Computational Physiology Lab, Department of Neurobiology and Behavior, Cornell University Ithaca, NY, USA
| | - Seungdo J Reiner
- Computational Physiology Lab, Department of Neurobiology and Behavior, Cornell University Ithaca, NY, USA
| | - Matthew Ennis
- Computational Physiology Lab, Department of Neurobiology and Behavior, Cornell University Ithaca, NY, USA
| | - Christiane Linster
- Computational Physiology Lab, Department of Neurobiology and Behavior, Cornell University Ithaca, NY, USA
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64
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Activation of the Shoulder Belt and Shoulder Muscles in Humans Providing Generation of “Two-Joint” Isometric Efforts. NEUROPHYSIOLOGY+ 2015. [DOI: 10.1007/s11062-015-9481-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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65
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Layer- and Area-Specificity of the Adrenergic Modulation of Synaptic Transmission in the Rat Neocortex. Neurochem Res 2014; 39:2377-84. [DOI: 10.1007/s11064-014-1440-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 09/10/2014] [Accepted: 09/18/2014] [Indexed: 10/24/2022]
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66
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Linster C, Fontanini A. Functional neuromodulation of chemosensation in vertebrates. Curr Opin Neurobiol 2014; 29:82-7. [PMID: 24971592 DOI: 10.1016/j.conb.2014.05.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 05/30/2014] [Indexed: 10/25/2022]
Abstract
Neuromodulation can be defined as a biophysical process that serves to modify-or modulate-the computation performed by a neuron or network as a function of task demands and behavioral state of the animal. These modulatory effects often involve substances extrinsic to the network under observation, such as acetylcholine (ACh), norepinephrine (NE), histamine, serotonin (5-HT), dopamine (DA), and a variety of neuropeptides. Olfactory and gustatory processes especially need to be adaptive and respond flexibly to changing environments, availability of resources and physiological needs. It is therefore crucial to understand the neuromodulatory processes that regulate the function of these systems.
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Affiliation(s)
- Christiane Linster
- Computational Physiology Lab, Department of Neurobiology and Behavior, Mudd Hall W249, Cornell University, Ithaca, NY 14853, USA.
| | - Alfredo Fontanini
- Dept. of Neurobiology and Behavior, Graduate Program in Neuroscience, State University of New York at Stony Brook, Stony Brook, NY 11794, USA.
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67
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Hecht PM, Will MJ, Schachtman TR, Welby LM, Beversdorf DQ. Beta-adrenergic antagonist effects on a novel cognitive flexibility task in rodents. Behav Brain Res 2014; 260:148-54. [DOI: 10.1016/j.bbr.2013.11.041] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 11/23/2013] [Accepted: 11/24/2013] [Indexed: 11/16/2022]
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68
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Cahana-Amitay D, Albert ML, Oveis A. Psycholinguistics of Aphasia Pharmacotherapy: Asking the Right Questions. APHASIOLOGY 2014; 28:133-154. [PMID: 24489425 PMCID: PMC3904395 DOI: 10.1080/02687038.2013.818099] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
BACKGROUND Among the obstacles to demonstrating efficacy of pharmacological intervention for aphasia is quantifying patients' responses to treatment in a statistically valid and reliable manner. In many of the review papers on this topic (e.g., Berthier et al., 2011; de Boissezon, Peran, de Boysson, & Démonet, 2007; Small & Llano, 2009), detailed discussions of various methodological problems are highlighted, with some suggestions on how these shortcomings should be addressed. Given this deep understanding of caveats associated with the experimental design of aphasia pharmacotherapy studies (e.g., Berthier et al., 2011), investigations continue to produce inconsistent results. AIM In this review paper we suggest that inclusion of theory-driven linguistic measures in aphasia pharmacotherapy studies would add an important step toward elucidating precise patterns of improvement in language performance resulting from pharmacotherapeutic intervention. MAIN CONTRIBUTION We provide a brief review of the clinical approaches currently used in pharmacotherapy studies of aphasia, which often lack psycholinguistic grounding. We then present ways in which psycholinguistic models can complement this approach, offering a rationale for task selection, and as a result, lead to a better understanding of treatment effects. We then follow with an example of how such an integrative approach can be implemented in studies targeting stress reduction in people with aphasia, via beta-blocking agents, as a means to augment language performance, using the psycholinguistic framework of "linguistic anxiety" outlined in Cahana-Amitay et al, 2011 as our guideline. CONCLUSION We conclude that the incorporation of psycholinguistic models into aphasia pharmacotherapy studies can increase the resolution with which we can identify functional changes.
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Affiliation(s)
- Dalia Cahana-Amitay
- Boston University School of Medicine, Department of Neurology, Harold Goodglass Aphasia Research Center, VA Boston Healthcare System, 150 South Huntington Avenue Boston, MA02130
| | - Martin L Albert
- Boston University School of Medicine, Department of Neurology, Harold Goodglass Aphasia Research Center, VA Boston Healthcare System, 150 South Huntington Avenue Boston, MA02130
| | - Abigail Oveis
- Boston University School of Medicine, Department of Neurology, Harold Goodglass Aphasia Research Center, VA Boston Healthcare System, 150 South Huntington Avenue Boston, MA02130
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69
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Yuan Q, Shakhawat AMD, Harley CW. Mechanisms underlying early odor preference learning in rats. PROGRESS IN BRAIN RESEARCH 2014; 208:115-56. [PMID: 24767481 DOI: 10.1016/b978-0-444-63350-7.00005-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Early odor preference training in rat pups produces behavioral preferences that last from hours to lifetimes. Here, we discuss the molecular and circuitry changes we have observed in the olfactory bulb (OB) and in the anterior piriform cortex (aPC) following odor training. For normal preference learning, both structures are necessary, but learned behavior can be initiated by initiating local circuit change in either structure. Our evidence relates dynamic molecular and circuit changes to memory duration and storage localization. Results using this developmental model are consistent with biological memory theories implicating N-methyl-D-aspartate (NMDA) receptors and β-adrenoceptors, and their associated cascades, in memory induction and consolidation. Finally, our examination of the odor preference model reveals a primary role for increases in α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor synaptic strength, and in network strength, in the creation and maintenance of preference memory in both olfactory structures.
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Affiliation(s)
- Qi Yuan
- Biomedical Sciences, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada.
| | - Amin M D Shakhawat
- Biomedical Sciences, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
| | - Carolyn W Harley
- Department of Psychology, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada.
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Abstract
Autism spectrum conditions (ASCs) are defined behaviorally, but they also involve multileveled disturbances of underlying biology that find striking parallels in the physiological impacts of electromagnetic frequency and radiofrequency radiation exposures (EMF/RFR). Part I (Vol 776) of this paper reviewed the critical contributions pathophysiology may make to the etiology, pathogenesis and ongoing generation of behaviors currently defined as being core features of ASCs. We reviewed pathophysiological damage to core cellular processes that are associated both with ASCs and with biological effects of EMF/RFR exposures that contribute to chronically disrupted homeostasis. Many studies of people with ASCs have identified oxidative stress and evidence of free radical damage, cellular stress proteins, and deficiencies of antioxidants such as glutathione. Elevated intracellular calcium in ASCs may be due to genetics or may be downstream of inflammation or environmental exposures. Cell membrane lipids may be peroxidized, mitochondria may be dysfunctional, and various kinds of immune system disturbances are common. Brain oxidative stress and inflammation as well as measures consistent with blood-brain barrier and brain perfusion compromise have been documented. Part II of this paper documents how behaviors in ASCs may emerge from alterations of electrophysiological oscillatory synchronization, how EMF/RFR could contribute to these by de-tuning the organism, and policy implications of these vulnerabilities. It details evidence for mitochondrial dysfunction, immune system dysregulation, neuroinflammation and brain blood flow alterations, altered electrophysiology, disruption of electromagnetic signaling, synchrony, and sensory processing, de-tuning of the brain and organism, with autistic behaviors as emergent properties emanating from this pathophysiology. Changes in brain and autonomic nervous system electrophysiological function and sensory processing predominate, seizures are common, and sleep disruption is close to universal. All of these phenomena also occur with EMF/RFR exposure that can add to system overload ('allostatic load') in ASCs by increasing risk, and can worsen challenging biological problems and symptoms; conversely, reducing exposure might ameliorate symptoms of ASCs by reducing obstruction of physiological repair. Various vital but vulnerable mechanisms such as calcium channels may be disrupted by environmental agents, various genes associated with autism or the interaction of both. With dramatic increases in reported ASCs that are coincident in time with the deployment of wireless technologies, we need aggressive investigation of potential ASC-EMF/RFR links. The evidence is sufficient to warrant new public exposure standards benchmarked to low-intensity (non-thermal) exposure levels now known to be biologically disruptive, and strong, interim precautionary practices are advocated.
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Wang HX, Waterhouse BD, Gao WJ. Selective suppression of excitatory synapses on GABAergic interneurons by norepinephrine in juvenile rat prefrontal cortical microcircuitry. Neuroscience 2013; 246:312-28. [PMID: 23684615 DOI: 10.1016/j.neuroscience.2013.05.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Revised: 04/12/2013] [Accepted: 05/02/2013] [Indexed: 11/29/2022]
Abstract
The noradrenergic system of the brain is thought to facilitate neuronal processes that promote behavioral activation, alertness, and attention. It is known that norepinephrine (NE) can be significantly elevated in the prefrontal cortex under normal conditions such as arousal and attention, and following the administration of psychostimulants and various other drugs prescribed for psychiatric disorders. However, how NE modulates neuronal activity and synapses in the local prefrontal circuitry remains elusive. In this study, we characterized the actions of NE on individual monosynaptic connections among layer V pyramidal neurons (P) and fast-spiking (FS) GABAergic interneurons in the juvenile (postnatal days 20-23) rat prefrontal local circuitry. We found that NE selectively depresses excitatory synaptic transmission in P-FS connections but has no detectable effect on the excitatory synapses in P-P connections and the inhibitory synapses in FS-P connections. NE apparently exerts distinctly different modulatory actions on identified synapses that target GABAergic interneurons but has no effect on those in the pyramidal neurons in this specific developmental period. These results indicate that, depending on the postsynaptic targets, the effects of NE in prefrontal cortex are synapse-specific, at least in the juvenile animals.
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Affiliation(s)
- H-X Wang
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA 19129, United States
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72
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Differential effects of cholinergic and noradrenergic neuromodulation on spontaneous cortical network dynamics. Neuropharmacology 2013; 72:259-73. [PMID: 23643755 DOI: 10.1016/j.neuropharm.2013.04.045] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2013] [Revised: 04/19/2013] [Accepted: 04/22/2013] [Indexed: 11/23/2022]
Abstract
Cholinergic and noradrenergic neuromodulation play a key role in determining overall behavioral state by shaping the underlying cortical network dynamics. The effects of these systems on synaptic and intrinsic cellular targets are quite diverse and a comprehensive understanding of how these neuromodulators regulate (spontaneous) cortical network activity has remained elusive. Here, we used multielectrode electrophysiology in vitro to investigate the effect of these neuromodulators on spontaneous network dynamics in acute slices of mouse visual cortex. We found that application of Carbachol (CCh) and Norepinephrine (NE) both enhanced the spontaneous network dynamics by increasing (1) the activity levels, (2) the temporal complexity of the network activity, and (3) the spatial complexity by decorrelating the network activity over a wide range of neuromodulator concentrations (1 μM, 10 μM, 50 μM, and 100 μM). Interestingly, we found that cholinergic neuromodulation was limited to the presence of CCh in the bath whereas the effects of NE, in particular for higher concentrations, induced plasticity that caused outlasting effects most prominently in the deep cortical layers. Together, these results provide a comprehensive network-level understanding of the similarities and differences of cholinergic and noradrenergic modulation of spontaneous network dynamics.
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73
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Shao YF, Zhao P, Dong CY, Li J, Kong XP, Wang HL, Dai LR, Hou YP. Neuropeptide S facilitates mice olfactory function through activation of cognate receptor-expressing neurons in the olfactory cortex. PLoS One 2013; 8:e62089. [PMID: 23614017 PMCID: PMC3628337 DOI: 10.1371/journal.pone.0062089] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 03/16/2013] [Indexed: 12/26/2022] Open
Abstract
Neuropeptide S (NPS) is a newly identified neuromodulator located in the brainstem and regulates various biological functions by selectively activating the NPS receptors (NPSR). High level expression of NPSR mRNA in the olfactory cortex suggests that NPS-NPSR system might be involved in the regulation of olfactory function. The present study was undertaken to investigate the effects of intracerebroventricular (i.c.v.) injection of NPS or co-injection of NPSR antagonist on the olfactory behaviors, food intake, and c-Fos expression in olfactory cortex in mice. In addition, dual-immunofluorescence was employed to identify NPS-induced Fos immunereactive (-ir) neurons that also bear NPSR. NPS (0.1–1 nmol) i.c.v. injection significantly reduced the latency to find the buried food, and increased olfactory differentiation of different odors and the total sniffing time spent in olfactory habituation/dishabituation tasks. NPS facilitated olfactory ability most at the dose of 0.5 nmol, which could be blocked by co-injection of 40 nmol NPSR antagonist [D-Val5]NPS. NPS administration dose-dependently inhibited food intake in fasted mice. Ex-vivo c-Fos and NPSR immunohistochemistry in the olfactory cortex revealed that, as compared with vehicle-treated mice, NPS markedly enhanced c-Fos expression in the anterior olfactory nucleus (AON), piriform cortex (Pir), ventral tenia tecta (VTT), the anterior cortical amygdaloid nucleus (ACo) and lateral entorhinal cortex (LEnt). The percentage of Fos-ir neurons that also express NPSR were 88.5% and 98.1% in the AON and Pir, respectively. The present findings demonstrated that NPS, via selective activation of the neurons bearing NPSR in the olfactory cortex, facilitates olfactory function in mice.
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Affiliation(s)
- Yu-Feng Shao
- Departments of Neuroscience, Anatomy, Histology, and Embryology, Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China
| | - Peng Zhao
- Departments of Neuroscience, Anatomy, Histology, and Embryology, Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China
| | - Chao-Yu Dong
- Departments of Neuroscience, Anatomy, Histology, and Embryology, Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China
| | - Jing Li
- Departments of Neuroscience, Anatomy, Histology, and Embryology, Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China
| | - Xiang-Pan Kong
- Departments of Neuroscience, Anatomy, Histology, and Embryology, Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China
| | - Hai-Liang Wang
- Departments of Neuroscience, Anatomy, Histology, and Embryology, Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China
| | - Li-Rong Dai
- Departments of Neuroscience, Anatomy, Histology, and Embryology, Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China
| | - Yi-Ping Hou
- Departments of Neuroscience, Anatomy, Histology, and Embryology, Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China
- * E-mail:
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74
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Morrison GL, Fontaine CJ, Harley CW, Yuan Q. A role for the anterior piriform cortex in early odor preference learning: evidence for multiple olfactory learning structures in the rat pup. J Neurophysiol 2013; 110:141-52. [PMID: 23576704 DOI: 10.1152/jn.00072.2013] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
cFos activation in the anterior piriform cortex (aPC) occurs in early odor preference learning in rat pups (Roth and Sullivan 2005). Here we provide evidence that the pairing of odor as a conditioned stimulus and β-adrenergic activation in the aPC as an unconditioned stimulus generates early odor preference learning. β-Adrenergic blockade in the aPC prevents normal preference learning. Enhancement of aPC cAMP response element-binding protein (CREB) phosphorylation in trained hemispheres is consistent with a role for this cascade in early odor preference learning in the aPC. In vitro experiments suggested theta-burst-mediated long-term potentiation (LTP) at the lateral olfactory tract (LOT) to aPC synapse depends on N-methyl-D-aspartate (NMDA) receptors and can be significantly enhanced by β-adrenoceptor activation, which causes increased glutamate release from LOT synapses during LTP induction. NMDA receptors in aPC are also shown to be critical for the acquisition, but not expression, of odor preference learning, as would be predicted if they mediate initial β-adrenoceptor-promoted aPC plasticity. Ex vivo experiments 3 and 24 h after odor preference training reveal an enhanced LOT-aPC field excitatory postsynaptic potential (EPSP). At 3 h both presynaptic and postsynaptic potentiations support EPSP enhancement while at 24 h only postsynaptic potentiation is seen. LOT-LTP in aPC is excluded by odor preference training. Taken together with earlier work on the role of the olfactory bulb in early odor preference learning, these outcomes suggest early odor preference learning is normally supported by and requires multiple plastic changes at least at two levels of olfactory circuitry.
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Affiliation(s)
- Gillian L Morrison
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
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75
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Edeline JM. Beyond traditional approaches to understanding the functional role of neuromodulators in sensory cortices. Front Behav Neurosci 2012; 6:45. [PMID: 22866031 PMCID: PMC3407859 DOI: 10.3389/fnbeh.2012.00045] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 07/03/2012] [Indexed: 02/01/2023] Open
Abstract
Over the last two decades, a vast literature has described the influence of neuromodulatory systems on the responses of sensory cortex neurons (review in Gu, 2002; Edeline, 2003; Weinberger, 2003; Metherate, 2004, 2011). At the single cell level, facilitation of evoked responses, increases in signal-to-noise ratio, and improved functional properties of sensory cortex neurons have been reported in the visual, auditory, and somatosensory modality. At the map level, massive cortical reorganizations have been described when repeated activation of a neuromodulatory system are associated with a particular sensory stimulus. In reviewing our knowledge concerning the way the noradrenergic and cholinergic system control sensory cortices, I will point out that the differences between the protocols used to reveal these effects most likely reflect different assumptions concerning the role of the neuromodulators. More importantly, a gap still exists between the descriptions of neuromodulatory effects and the concepts that are currently applied to decipher the neural code operating in sensory cortices. Key examples that bring this gap into focus are the concept of cell assemblies and the role played by the spike timing precision (i.e., by the temporal organization of spike trains at the millisecond time-scale) which are now recognized as essential in sensory physiology but are rarely considered in experiments describing the role of neuromodulators in sensory cortices. Thus, I will suggest that several lines of research, particularly in the field of computational neurosciences, should help us to go beyond traditional approaches and, ultimately, to understand how neuromodulators impact on the cortical mechanisms underlying our perceptual abilities.
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Affiliation(s)
- Jean-Marc Edeline
- Centre de Neurosciences Paris-Sud, CNRS UMR 8195, Université Paris-Sud, Bâtiment Orsay Cedex, France
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76
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Anderson CJ, Colombo J, Unruh KE. Pupil and salivary indicators of autonomic dysfunction in autism spectrum disorder. Dev Psychobiol 2012; 55:465-82. [PMID: 22644965 DOI: 10.1002/dev.21051] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Accepted: 05/02/2012] [Indexed: 02/03/2023]
Abstract
Dysregulated tonic pupil size has been reported in autism spectrum disorder (ASD). Among the possible sources of this dysregulation are disruptions in the feedback loop between norepinephrine (NE) and hypothalamic systems. In the current study, we examined afternoon levels of salivary alpha-amylase (sAA, a putative correlate of NE) and cortisol (used to assess stress-based responses) in two independent samples of children with ASD. We found a larger pupil size and lower sAA levels in ASD, compared to typical and clinical age-matched controls. This was substantiated at the individual level, as sAA levels were strongly correlated with tonic pupil size. Relatively little diurnal variation in sAA taken in the home environment in the ASD group was also observed, while typical controls showed a significant linear increase throughout the day. Results are discussed in terms of potential early biomarkers and the elucidation of underlying neural dysfunction in ASD.
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Affiliation(s)
- Christa J Anderson
- Life Span Institute, Neurocognitive Development of Autism Research Laboratory, The University of Kansas, 1000 Sunnyside Avenue, Room 1052, Lawrence, KS 66045, USA.
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77
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Noradrenergic moderation of working memory impairments in adults with autism spectrum disorder. J Int Neuropsychol Soc 2012; 18:556-64. [PMID: 22414705 DOI: 10.1017/s1355617712000070] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In addition to having difficulties with social communications, individuals with an autism spectrum disorder (ASD) often also experience impairment in higher-order, executive skills. The present study examined the effects of pharmacological modulation of the norepinephrine system on the severity of such impairments. A sample of 14 high-functioning adults with ASD and a demographically-matched comparison group of 13 typically developing individuals participated. An AX continuous performance test (AX-CPT) was used to evaluate working memory and inhibitory control. AX-CPT performance was assessed following administration of a single dose of propranolol (a beta adrenergic antagonist) and following placebo (sugar pill) administration. Individuals with ASD performed more poorly than non-ASD individuals in the working memory condition (BX trials). Importantly, administration of propranolol attenuated this impairment, with the ASD group performing significantly better in the propranolol condition than the placebo condition. Working memory performance of the non-ASD group was unaffected by propranolol/placebo administration. No group or medication effects were observed for the inhibition condition (AY trials). The present findings suggest that norepinephrine may play a role in some, but not necessarily all, cognitive impairments associated with ASD. Additional research is needed to fully understand whether this role is primarily causal or compensatory in nature.
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78
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Abstract
Consciousness is subjective experience. During both sleep and anesthesia, consciousness is common, evidenced by dreaming. A defining feature of dreaming is that, while conscious, we do not experience our environment; we are disconnected. Besides inducing behavioral unresponsiveness, a key goal of anesthesia is to prevent the experience of surgery (connected consciousness), by inducing either unconsciousness or disconnection of consciousness from the environment. Review of the isolated forearm technique demonstrates that consciousness, connectedness, and responsiveness uncouple during anesthesia; in clinical conditions, a median 37% of patients demonstrate connected consciousness. We describe potential neurobiological constructs that can explain this phenomenon: during light anesthesia the subcortical mechanisms subserving spontaneous behavioral responsiveness are disabled but information integration within the corticothalamic network continues to produce consciousness, and unperturbed norepinephrinergic signaling maintains connectedness. These concepts emphasize the need for developing anesthetic regimens and depth of anesthesia monitors that specifically target mechanisms of consciousness, connectedness, and responsiveness.
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Affiliation(s)
- Robert D Sanders
- Department of Anaesthetics, Intensive Care & Pain Medicine, Imperial College London, London, United Kingdom.
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79
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Abstract
Natural odors, generally composed of many monomolecular components, are analyzed by peripheral receptors into component features and translated into spatiotemporal patterns of neural activity in the olfactory bulb. Here, we will discuss the role of the olfactory cortex in the recognition, separation and completion of those odor-evoked patterns, and how these processes contribute to odor perception. Recent findings regarding the neural architecture, physiology, and plasticity of the olfactory cortex, principally the piriform cortex, will be described in the context of how this paleocortical structure creates odor objects.
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Affiliation(s)
- Donald A Wilson
- Emotional Brain Institute, Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA.
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80
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Abstract
The brain continuously adapts its processing machinery to behavioural demands. To achieve this, it rapidly modulates the operating mode of cortical circuits, controlling the way that information is transformed and routed. This article will focus on two experimental approaches by which the control of cortical information processing has been investigated: the study of state-dependent cortical processing in rodents and attention in the primate visual system. Both processes involve a modulation of low-frequency activity fluctuations and spiking correlation, and are mediated by common receptor systems. We suggest that selective attention involves processes that are similar to state change, and that operate at a local columnar level to enhance the representation of otherwise non-salient features while suppressing internally generated activity patterns.
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Affiliation(s)
- Kenneth D Harris
- Department of Bioengineering, Imperial College, London SW7 2AZ, UK. kenneth.harris@ imperial.ac.uk
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81
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Deco G, Thiele A. Cholinergic control of cortical network interactions enables feedback-mediated attentional modulation. Eur J Neurosci 2011; 34:146-57. [PMID: 21692884 DOI: 10.1111/j.1460-9568.2011.07749.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Attention increases our ability to detect behaviorally relevant stimuli. At the neuronal level this is supported by increased firing rates of neurons representing the attended object. In primary visual cortex an attention-mediated activity increase depends on the presence of the neuromodulator acetylcholine. Using a spiking network model of visual cortex we have investigated how acetylcholine interacts with biased feedback to enable attentional processing. Although acetylcholine affects cortical processing in a multitude of manners, we restricted our analysis to four of its main established actions. These were (i) a reduction in firing rate adaptation by reduction in M-currents (muscarinic), (ii) an increase in thalamocortical synaptic efficacy by nicotinic presynaptic receptors, (iii) a reduction in lateral interactions by muscarinic presynaptic receptors, and (iv) an increase in inhibitory drive by muscarinic receptors located on inhibitory interneurons. We found that acetylcholine contributes to feedback-mediated attentional modulation, mostly by reducing intracortical interactions and also to some extent by increasing the inhibitory drive. These findings help explain why acetylcholine is necessary for top-down-driven attentional modulation, and suggest a close interdependence of cholinergic and feedback drive in mediating cognitive function.
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Affiliation(s)
- Gustavo Deco
- Department of Technology, Computational Neuroscience, Institució Catalana de Recerca i Estudis Avançats (ICREA), Universitat Pompeu Fabra, Roc Boronat, 138, 08018 Barcelona, Spain.
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82
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Cahana-Amitay D, Albert ML, Pyun SB, Westwood A, Jenkins T, Wolford S, Finley M. Language as a Stressor in Aphasia. APHASIOLOGY 2011; 25:593-614. [PMID: 22701271 PMCID: PMC3372975 DOI: 10.1080/02687038.2010.541469] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
BACKGROUND: Persons with aphasia often report feeling anxious when using language while communicating. While many patients, caregivers, clinicians and researchers would agree that language may be a stressor for persons with aphasia, systematic empirical studies of stress and/or anxiety in aphasia remain scarce. AIM: The aim of this paper is to review the existing literature discussing language as a stressor in aphasia, identify key issues, highlight important gaps, and propose a program for future study. In doing so, we hope to underscore the importance of understanding aspects of the emotional aftermath of aphasia, which plays a critical role in the process of recovery and rehabilitation. MAIN CONTRIBUTION: Post stroke emotional dysregulation in persons with chronic aphasia clearly has adverse effects for language performance and prospects of recovery. However, the specific role anxiety might play in aphasia has yet to be determined. As a starting point, we propose to view language in aphasia as a stressor, linked to an emotional state we term "linguistic anxiety." Specifically, a person with linguistic anxiety is one in whom the deliberate, effortful production of language involves anticipation of an error, with the imminence of linguistic failure serving as the threat. Since anticipation is psychologically linked to anxiety and also plays an important role in the allostatic system, we suggest that examining physiologic stress responses in persons with aphasia when they are asked to perform a linguistic task would be a productive tool for assessing the potential relation of stress to "linguistic anxiety." CONCLUSION: Exploring the putative relationship between anxiety and language in aphasia, through the study of physiologic stress responses, could establish a platform for investigating language changes in the brain in other clinical populations, such as in individuals with Alzheimer's disease or persons with post traumatic stress disorder, or even with healthy aging persons, in whom "linguistic anxiety" might be at work when they have trouble finding words.
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Affiliation(s)
- Dalia Cahana-Amitay
- Boston University, Department of Neurology, Harold Goodglass Aphasia Research Center, VA Healthcare System, 150 South Huntington Avenue Boston, MA 02130
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Linster C, Nai Q, Ennis M. Nonlinear effects of noradrenergic modulation of olfactory bulb function in adult rodents. J Neurophysiol 2011; 105:1432-43. [PMID: 21273323 PMCID: PMC3075300 DOI: 10.1152/jn.00960.2010] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Accepted: 01/25/2011] [Indexed: 01/28/2023] Open
Abstract
The mammalian main olfactory bulb receives a significant noradrenergic input from the locus coeruleus. Norepinephrine (NE) is involved in acquisition of conditioned odor preferences in neonatal animals, in some species-specific odor-dependent behaviors, and in adult odor perception. We provide a detailed review of the functional role of NE in adult rodent main olfactory bulb function. We include cellular, synaptic, network, and behavioral data and use computational simulations to tie these different types of data together.
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Affiliation(s)
- Christiane Linster
- Department of Neurobiology and Behavior, W245 Mudd Hall, Cornell University, Ithaca, NY 14853, USA.
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84
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Breckel TP, Giessing C, Thiel CM. Impact of brain networks involved in vigilance on processing irrelevant visual motion. Neuroimage 2011; 55:1754-62. [DOI: 10.1016/j.neuroimage.2011.01.025] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Revised: 12/26/2010] [Accepted: 01/11/2011] [Indexed: 10/18/2022] Open
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85
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Wang LE, Fink GR, Diekhoff S, Rehme AK, Eickhoff SB, Grefkes C. Noradrenergic enhancement improves motor network connectivity in stroke patients. Ann Neurol 2010; 69:375-88. [PMID: 21387380 DOI: 10.1002/ana.22237] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2010] [Revised: 08/12/2010] [Accepted: 08/20/2010] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Both animal and human data suggest that noradrenergic stimulation may enhance motor performance after brain damage. We conducted a placebo-controlled, double-blind and crossover design study to investigate the effects of noradrenergic stimulation on the cortical motor system in hemiparetic stroke patients. METHODS Stroke patients (n = 11) in the subacute or chronic stage with mild-to-moderate hand paresis received a single oral dose of 6 mg reboxetine (RBX), a selective noradrenaline reuptake inhibitor. We used functional magnetic resonance imaging and dynamic causal modeling to assess changes in neural activity and interregional effective connectivity while patients moved their paretic hand. RESULTS RBX stimulation significantly increased maximum grip power and index finger-tapping frequency of the paretic hand. Enhanced motor performance was associated with a reduction of cortical "hyperactivity" toward physiological levels as observed in healthy control subjects, especially in the ipsilesional ventral premotor cortex (vPMC) and supplementary motor area (SMA), but also in the temporoparietal junction and prefrontal cortex. Connectivity analyses revealed that in stroke patients neural coupling with SMA or vPMC was significantly reduced compared with healthy controls. This "hypoconnectivity" was partially normalized when patients received RBX, especially for the coupling of ipsilesional SMA with primary motor cortex. INTERPRETATION The data suggest that noradrenergic stimulation by RBX may help to modulate the pathologically altered motor network architecture in stroke patients, resulting in increased coupling of ipsilesional motor areas and thereby improved motor function.
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Affiliation(s)
- Ling E Wang
- Cognitive Neurology Section, Institute of Neuroscience and Medicine, Research Centre Juelich, Germany
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86
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Fletcher ML, Chen WR. Neural correlates of olfactory learning: Critical role of centrifugal neuromodulation. Learn Mem 2010; 17:561-70. [PMID: 20980444 DOI: 10.1101/lm.941510] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The mammalian olfactory system is well established for its remarkable capability of undergoing experience-dependent plasticity. Although this process involves changes at multiple stages throughout the central olfactory pathway, even the early stages of processing, such as the olfactory bulb and piriform cortex, can display a high degree of plasticity. As in other sensory systems, this plasticity can be controlled by centrifugal inputs from brain regions known to be involved in attention and learning processes. Specifically, both the bulb and cortex receive heavy inputs from cholinergic, noradrenergic, and serotonergic modulatory systems. These neuromodulators are shown to have profound effects on both odor processing and odor memory by acting on both inhibitory local interneurons and output neurons in both regions.
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Affiliation(s)
- Max L Fletcher
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA.
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87
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Abstract
A decrease in interaction between brain regions is observed in individuals with autism spectrum disorder (ASD), which is believed to be related to restricted neural network access in ASD. Propranolol, a beta-adrenergic antagonist, has revealed benefit during performance of tasks involving flexibility of access to networks, a benefit also seen in ASD. Our goal was to determine the effect of propranolol on functional connectivity in ASD during a verbal decision making task as compared to nadolol, thereby accounting for the potential spurious fMRI effects due to peripheral hemodynamic effects of propranolol. Ten ASD subjects underwent fMRI scans after administration of placebo, propranolol or nadolol, while performing a phonological decision making task. Comparison of functional connectivity between pre-defined ROI-pairs revealed a significant increase with propranolol compared to nadolol, suggesting a potential imaging marker for the cognitive effects of propranolol in ASD.
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88
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Renner KH, Beversdorf DQ. Effects of naturalistic stressors on cognitive flexibility and working memory task performance. Neurocase 2010; 16:293-300. [PMID: 20169503 DOI: 10.1080/13554790903463601] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Experimental stressors impair performance on tasks requiring certain types of cognitive flexibility, an effect that may be mediated by the noradrenergic system. The goal of this experiment was to examine the effects of psychological stress on cognitive flexibility in problem solving and immediate memory with a more naturalistic psychological stressor, and examine the interaction between subject ability and the cognitive effects of psychological stress. Twenty subjects performed the compound remote associates task (CRA) and a number series recall task after watching the first 30 minutes of 'Saving Private Ryan' and after the first 30 minutes of 'Shrek', with condition order and test version order counterbalanced. An interaction effect was observed between stress and subject ability for the CRA, with performance on the CRA significantly worse after the stress film among those performing well on the task. No effects were found on the memory task. Therefore, the naturalistic stressor impairs cognitive flexibility in a manner dependent upon how much difficulty the subject has with these types of tasks. Further work will be necessary to better understand the pharmacological mechanism of the effects of these types of stressors, and the clinical implications of this effect.
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89
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Escanilla O, Arrellanos A, Karnow A, Ennis M, Linster C. Noradrenergic modulation of behavioral odor detection and discrimination thresholds in the olfactory bulb. Eur J Neurosci 2010; 32:458-68. [DOI: 10.1111/j.1460-9568.2010.07297.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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90
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Sontag TA, Tucha O, Walitza S, Lange KW. Animal models of attention deficit/hyperactivity disorder (ADHD): a critical review. ACTA ACUST UNITED AC 2010; 2:1-20. [DOI: 10.1007/s12402-010-0019-x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Accepted: 01/02/2010] [Indexed: 01/04/2023]
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91
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Greenwood PM, Sundararajan R, Lin MK, Kumar R, Fryxell KJ, Parasuraman R. Both a nicotinic single nucleotide polymorphism (SNP) and a noradrenergic SNP modulate working memory performance when attention is manipulated. J Cogn Neurosci 2009; 21:2139-53. [PMID: 19016604 DOI: 10.1162/jocn.2008.21164] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
We investigated the relation between the two systems of visuospatial attention and working memory by examining the effect of normal variation in cholinergic and noradrenergic genes on working memory performance under attentional manipulation. We previously reported that working memory for location was impaired following large location precues, indicating the scale of visuospatial attention has a role in forming the mental representation of the target. In one of the first studies to compare effects of two single nucleotide polymorphisms (SNPs) on the same cognitive task, we investigated the neurotransmission systems underlying interactions between attention and memory. Based on our previous report that the CHRNA4 rs#1044396 C/T nicotinic receptor SNP affected visuospatial attention, but not working memory, and the DBH rs#1108580 G/A noradrenergic enzyme SNP affected working memory, but not attention, we predicted that both SNPs would modulate performance when the two systems interacted and working memory was manipulated by attention. We found the scale of visuospatial attention deployed around a target affected memory for location of that target. Memory performance was modulated by the two SNPs. CHRNA4 C/C homozygotes and DBH G allele carriers showed the best memory performance but also the greatest benefit of visuospatial attention on memory. Overall, however, the CHRNA4 SNP exerted a stronger effect than the DBH SNP on memory performance when visuospatial attention was manipulated. This evidence of an integrated cholinergic influence on working memory performance under attentional manipulation is consistent with the view that working memory and visuospatial attention are separate systems which can interact.
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92
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Longden KD, Krapp HG. State-dependent performance of optic-flow processing interneurons. J Neurophysiol 2009; 102:3606-18. [PMID: 19812292 DOI: 10.1152/jn.00395.2009] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Active locomotive states are metabolically expensive and require efficient sensory processing both to avoid wasteful movements and to cope with an extended bandwidth of sensory stimuli. This is particularly true for flying animals because flight, as opposed to walking or resting, imposes a steplike increase in metabolism for the precise execution and control of movements. Sensory processing itself carries a significant metabolic cost, but the principles governing the adjustment of sensory processing to different locomotor states are not well understood. We use the blowfly as a model system to study the impact on visual processing of a neuromodulator, octopamine, which is known to be involved in the regulation of flight physiology. We applied an octopamine agonist and recorded the directional motion responses of identified visual interneurons known to process self-motion-induced optic flow to directional motion stimuli. The neural response range of these neurons is increased and the response latency is reduced. We also found that, due to an elevated spontaneous spike rate, the cells' negative signaling range is increased. Meanwhile, the preferred self-motion parameters the cells encode were state independent. Our results indicate that in the blowfly energetically expensive sensory coding strategies, such as rapid, large responses, and high spontaneous spike activity could be adjusted by the neuromodulator octopamine, likely to save energy during quiet locomotor states.
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Affiliation(s)
- Kit D Longden
- Department of Bioengineering, Imperial College London, London, UK.
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93
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94
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Grefkes C, Wang LE, Eickhoff SB, Fink GR. Noradrenergic modulation of cortical networks engaged in visuomotor processing. ACTA ACUST UNITED AC 2009; 20:783-97. [PMID: 19687293 DOI: 10.1093/cercor/bhp144] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Both animal and human data suggest that stimulation of the noradrenergic system may influence neuronal excitability in regions engaged in sensory processing and visuospatial attention. We tested the hypothesis that the neural mechanisms subserving motor performance in tasks relying on the visuomotor control of goal-directed hand movements might be modulated by noradrenergic influences. Healthy subjects were stimulated using the selective noradrenaline reuptake inhibitor reboxetine (RBX) in a placebo-controlled crossover design. Functional magnetic resonance imaging and dynamic causal modeling (DCM) were used to assess drug-related changes in blood oxygen level-dependent activity and interregional connectivity while subjects performed a joystick task requiring goal-directed movements. Improved task performance under RBX was associated with increased activity in right visual, intraparietal and superior frontal cortex (premotor/frontal eye field). DCM revealed that the neuronal coupling among these regions was significantly enhanced when subjects were stimulated with RBX. Concurrently, right intraparietal cortex and right superior frontal cortex exerted a stronger driving influence on visuomotor areas of the left hemisphere, including SMA and M1. These effects were independent from task difficulty. The data suggest that stimulating noradrenergic mechanisms may rearrange the functional network architecture within and across the hemispheres, for example, by synaptic gating, thereby optimizing motor behavior.
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Affiliation(s)
- Christian Grefkes
- Neuromodulation & Neurorehabilitation, Max Planck Institute for Neurological Research, 50931 Cologne, Germany.
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95
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Castelino CB, Schmidt MF. What birdsong can teach us about the central noradrenergic system. J Chem Neuroanat 2009; 39:96-111. [PMID: 19686836 DOI: 10.1016/j.jchemneu.2009.08.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2009] [Revised: 07/31/2009] [Accepted: 08/04/2009] [Indexed: 01/23/2023]
Abstract
Increasing evidence indicates that the noradrenergic system plays a key role in biasing the nervous system towards producing behaviors that help animals adapt to constantly changing environments. Most of the studies investigating noradrenergic function are performed in animals that have a limited repertoire of tractable natural behaviors. Songbirds, in contrast, with their rich set of precisely quantifiable vocal behaviors, provide a unique model system to study the noradrenergic system. An additional advantage of this system is the existence of a well-defined neural circuit, known as the song system, that is necessary for the production, learning and perception of song and can be studied at many different levels. These include the ability to investigate the effect of norepinephrine on synaptic function using brain slices, identifying its influence on singing-related gene expression and monitoring its impact on the activity of single neurons recorded in awake behaving birds. In this review article, we describe the similarities and differences, both anatomical and functional, between the avian and mammalian noradrenergic system and its role in sensory processing, learning, attention and synaptic modulation. We also describe how the noradrenergic system influences motor production, an under-explored aspect of norepinephrine function in mammalian studies. We argue that the richness of behaviors observed in songbirds provides a unique opportunity to study the noradrenergic system in a highly integrative manner that will ultimately provide important insights into the role of this system in normal behavior and disease.
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Affiliation(s)
- Christina B Castelino
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, United States.
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96
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Adaptation by binding: a learning account of cognitive control. Trends Cogn Sci 2009; 13:252-7. [DOI: 10.1016/j.tics.2009.02.007] [Citation(s) in RCA: 221] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 02/25/2009] [Accepted: 02/25/2009] [Indexed: 12/30/2022]
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97
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Optimality and robustness of a biophysical decision-making model under norepinephrine modulation. J Neurosci 2009; 29:4301-11. [PMID: 19339624 DOI: 10.1523/jneurosci.5024-08.2009] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The locus ceruleus (LC) can exhibit tonic or phasic activity and release norepinephrine (NE) throughout the cortex, modulating cellular excitability and synaptic efficacy and thus influencing behavioral performance. We study the effects of LC-NE modulation on decision making in two-alternative forced-choice tasks by changing conductances in a biophysical neural network model, and we investigate how it affects performance measured in terms of reward rate. We find that low tonic NE levels result in unmotivated behavior and high levels in impulsive, inaccurate choices, but that near-optimal performance can occur over a broad middle range. Robustness is greatest when pyramidal cells are less strongly modulated than interneurons, and superior performance can be achieved with phasic NE release, provided only glutamatergic synapses are modulated. We also show that network functions such as sensory information accumulation and short-term memory can be modulated by tonic NE levels, and that previously observed diverse evoked cell responses may be due to network effects.
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98
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Saar D, Barkai E. Long-Lasting Maintenance of Learning-Induced Enhanced Neuronal Excitability: Mechanisms and Functional Significance. Mol Neurobiol 2009; 39:171-7. [DOI: 10.1007/s12035-009-8060-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Accepted: 02/18/2009] [Indexed: 11/29/2022]
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99
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Coactivation of M(1) muscarinic and alpha1 adrenergic receptors stimulates extracellular signal-regulated protein kinase and induces long-term depression at CA3-CA1 synapses in rat hippocampus. J Neurosci 2008; 28:5350-8. [PMID: 18480291 DOI: 10.1523/jneurosci.5058-06.2008] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Intact cholinergic innervation from the medial septum and noradrenergic innervation from the locus ceruleus are required for hippocampal-dependent learning and memory. However, much remains unclear about the precise roles of acetylcholine (ACh) and norepinephrine (NE) in hippocampal function, particularly in terms of how interactions between these two transmitter systems might play an important role in synaptic plasticity. Previously, we reported that activation of either muscarinic M(1) or adrenergic alpha1 receptors induces activity- and NMDA receptor-dependent long-term depression (LTD) at CA3-CA1 synapses in acute hippocampal slices, referred to as muscarinic LTD (mLTD) and norepinephrine LTD (NE LTD), respectively. In this study, we tested the hypothesis that mLTD and NE LTD are independent forms of LTD, yet require activation of a common Galphaq-coupled signaling pathway for their induction, and investigated the net effect of coactivation of M(1) and alpha1 receptors on the magnitude of LTD induced. We find that neither mLTD nor NE LTD requires phospholipase C activation, but both plasticities are prevented by inhibiting the Src kinase family and extracellular signal-regulated protein kinase (ERK) activation. Interestingly, LTD can be induced when M(1) and alpha1 agonists are coapplied at concentrations too low to induce LTD when applied separately, via a summed increase in ERK activation. Thus, because ACh and NE levels in vivo covary, especially during periods of memory encoding and consolidation, cooperative signaling through M(1) and alpha1 receptors could function to induce long-term changes in synaptic function important for cognition.
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100
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Tereshchenko Y, Brandewiede J, Schachner M, Irintchev A, Morellini F. Novelty-induced behavioral traits correlate with numbers of brainstem noradrenergic neurons and septal cholinergic neurons in C57BL/6J mice. Behav Brain Res 2008; 191:280-4. [PMID: 18468704 DOI: 10.1016/j.bbr.2008.03.034] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2008] [Accepted: 03/26/2008] [Indexed: 11/19/2022]
Abstract
It is generally accepted that different brain regions regulate specific behavioral responses and that structural alterations in these regions may affect behavior. We investigated whether inter-individual variability in novelty-induced behaviors in C57BL/6J mice correlates with numbers of noradrenergic neurons in the locus coeruleus and cholinergic neurons in the septum. We found that exploration of new stimuli correlated negatively with numbers of noradrenergic neurons, whereas anxiety correlated positively with numbers of cholinergic neurons. The observed correlations suggest physiologically plausible links between structure and function and indicate that precise morphological estimates can be predictive for behavioral responses.
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Affiliation(s)
- Yuliya Tereshchenko
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, Falkenried 94, Hamburg 20251, Germany
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