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Davies C, Appiah-Kusi E, Wilson R, Blest-Hopley G, Bossong MG, Valmaggia L, Brammer M, Perez J, Allen P, Murray RM, McGuire P, Bhattacharyya S. Altered relationship between cortisol response to social stress and mediotemporal function during fear processing in people at clinical high risk for psychosis: a preliminary report. Eur Arch Psychiatry Clin Neurosci 2022; 272:461-475. [PMID: 34480630 PMCID: PMC8938358 DOI: 10.1007/s00406-021-01318-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 08/11/2021] [Indexed: 12/11/2022]
Abstract
Evidence suggests that people at Clinical High Risk for Psychosis (CHR) have a blunted cortisol response to stress and altered mediotemporal activation during fear processing, which may be neuroendocrine-neuronal signatures of maladaptive threat responses. However, whether these facets are associated with each other and how this relationship is affected by cannabidiol treatment is unknown. We examined the relationship between cortisol response to social stress and mediotemporal function during fear processing in healthy people and in CHR patients. In exploratory analyses, we investigated whether treatment with cannabidiol in CHR individuals could normalise any putative alterations in cortisol-mediotemporal coupling. 33 CHR patients were randomised to 600 mg cannabidiol or placebo treatment. Healthy controls (n = 19) did not receive any drug. Mediotemporal function was assessed using a fearful face-processing functional magnetic resonance imaging paradigm. Serum cortisol and anxiety were measured immediately following the Trier Social Stress Test. The relationship between cortisol and mediotemporal blood-oxygen-level-dependent haemodynamic response was investigated using linear regression. In healthy controls, there was a significant negative relationship between cortisol and parahippocampal activation (p = 0.023), such that the higher the cortisol levels induced by social stress, the lower the parahippocampal activation (greater deactivation) during fear processing. This relationship differed significantly between the control and placebo groups (p = 0.033), but not between the placebo and cannabidiol groups (p = 0.67). Our preliminary findings suggest that the parahippocampal response to fear processing may be associated with the neuroendocrine (cortisol) response to experimentally induced social stress, and that this relationship may be altered in patients at clinical high risk for psychosis.
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Affiliation(s)
- Cathy Davies
- grid.13097.3c0000 0001 2322 6764Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London, SE5 8AF UK
| | - Elizabeth Appiah-Kusi
- grid.13097.3c0000 0001 2322 6764Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London, SE5 8AF UK
| | - Robin Wilson
- grid.13097.3c0000 0001 2322 6764Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London, SE5 8AF UK
| | - Grace Blest-Hopley
- grid.13097.3c0000 0001 2322 6764Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London, SE5 8AF UK
| | - Matthijs G. Bossong
- grid.5477.10000000120346234Department of Psychiatry, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Lucia Valmaggia
- grid.13097.3c0000 0001 2322 6764Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK ,grid.37640.360000 0000 9439 0839National Institute for Health Research (NIHR) Maudsley Biomedical Research Centre (BRC), South London and Maudsley NHS Foundation Trust, London, UK
| | - Michael Brammer
- grid.13097.3c0000 0001 2322 6764Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | - Jesus Perez
- grid.450563.10000 0004 0412 9303CAMEO Early Intervention Service, Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
| | - Paul Allen
- grid.13097.3c0000 0001 2322 6764Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London, SE5 8AF UK ,grid.35349.380000 0001 0468 7274Department of Psychology, University of Roehampton, London, UK ,grid.416167.30000 0004 0442 1996Icahn School of Medicine, Mount Sinai Hospital, New York, USA
| | - Robin M. Murray
- grid.13097.3c0000 0001 2322 6764Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London, SE5 8AF UK
| | - Philip McGuire
- grid.13097.3c0000 0001 2322 6764Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London, SE5 8AF UK ,grid.37640.360000 0000 9439 0839National Institute for Health Research (NIHR) Maudsley Biomedical Research Centre (BRC), South London and Maudsley NHS Foundation Trust, London, UK ,grid.37640.360000 0000 9439 0839Outreach and Support in South London (OASIS) Service, South London and Maudsley NHS Foundation Trust, London, UK
| | - Sagnik Bhattacharyya
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London, SE5 8AF, UK.
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Campbell A. Point Specificity of Acupuncture in the Light of Recent Clinical and Imaging Studies. Acupunct Med 2018; 24:118-22. [PMID: 17013358 DOI: 10.1136/aim.24.3.118] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
One fundamental question that is still not resolved is whether acupuncture needles must be inserted in specific points to have their greatest effects. In the majority of large RCTs recently conducted in Germany, acupuncture was significantly more effective than doing nothing but not than sham acupuncture. Only for one study of chronic knee pain was acupuncture superior to sham. Brain imaging with functional magnetic resonance (fMRI) and positron emission tomography (PET) may be helpful but is still in its early stages. Several studies have shown differences between the way the deep central areas of the brain respond to genuine acupuncture compared with sham. Acupuncture can clearly produce complex changes that are relevant to pain transmission and perception, though it is still uncertain how specific these are. Similar changes have been seen after the application of placebo cream and after hypnosis. A previous paper discussed the likely central role of the limbic system in acupuncture, evidenced by euphoria and out of body experiences. There may be a good deal of common ground between acupuncture, placebo treatments, hypnosis, and even manipulative treatments. This understanding could offer a way out of the sterile debate about whether acupuncture is merely a placebo: acupuncture could be one effective way of stimulating responses within these deep areas of the brain, though not the only way.
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Gonzalez-Escamilla G, Chirumamilla VC, Meyer B, Bonertz T, von Grotthus S, Vogt J, Stroh A, Horstmann JP, Tüscher O, Kalisch R, Muthuraman M, Groppa S. Excitability regulation in the dorsomedial prefrontal cortex during sustained instructed fear responses: a TMS-EEG study. Sci Rep 2018; 8:14506. [PMID: 30267020 PMCID: PMC6162240 DOI: 10.1038/s41598-018-32781-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 09/11/2018] [Indexed: 01/25/2023] Open
Abstract
Threat detection is essential for protecting individuals from adverse situations, in which a network of amygdala, limbic regions and dorsomedial prefrontal cortex (dmPFC) regions are involved in fear processing. Excitability regulation in the dmPFC might be crucial for fear processing, while abnormal patterns could lead to mental illness. Notwithstanding, non-invasive paradigms to measure excitability regulation during fear processing in humans are missing. To address this challenge we adapted an approach for excitability characterization, combining electroencephalography (EEG) and transcranial magnetic stimulation (TMS) over the dmPFC during an instructed fear paradigm, to dynamically dissect its role in fear processing. Event-related (ERP) and TMS-evoked potentials (TEP) were analyzed to trace dmPFC excitability. We further linked the excitability regulation patterns to individual MRI-derived gray matter structural integrity of the fear network. Increased cortical excitability was demonstrated to threat (T) processing in comparison to no-threat (NT), reflected by increased amplitude of evoked potentials. Furthermore, TMS at dmPFC enhanced the evoked responses during T processing, while the structural integrity of the dmPFC and amygdala predicted the excitability regulation patterns to fear processing. The dmPFC takes a special role during fear processing by dynamically regulating excitability. The applied paradigm can be used to non-invasively track response abnormalities to threat stimuli in healthy subjects or patients with mental disorders.
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Affiliation(s)
- Gabriel Gonzalez-Escamilla
- Section of Movement Disorders and Neurostimulation, Department of Neurology, Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg University Mainz, 55131, Mainz, Germany
| | - Venkata C Chirumamilla
- Section of Movement Disorders and Neurostimulation, Department of Neurology, Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg University Mainz, 55131, Mainz, Germany
| | - Benjamin Meyer
- Neuroimaging Center Mainz, Focus Program Translational Neuroscience, University Medical Center of the Johannes Gutenberg University Mainz, 55131, Mainz, Germany
| | - Tamara Bonertz
- Section of Movement Disorders and Neurostimulation, Department of Neurology, Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg University Mainz, 55131, Mainz, Germany
| | - Sarah von Grotthus
- Section of Movement Disorders and Neurostimulation, Department of Neurology, Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg University Mainz, 55131, Mainz, Germany
| | - Johannes Vogt
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center of the Johannes Gutenberg University Mainz, 55131, Mainz, Germany
| | - Albrecht Stroh
- Focus Program Translational Neurosciences, Institute for Microscopic Anatomy and Neurobiology, Johannes Gutenberg University Mainz, 55131, Mainz, Germany
| | - Johann-Philipp Horstmann
- Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg University Mainz, 55131, Mainz, Germany
| | - Oliver Tüscher
- Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg University Mainz, 55131, Mainz, Germany
| | - Raffael Kalisch
- Neuroimaging Center Mainz, Focus Program Translational Neuroscience, University Medical Center of the Johannes Gutenberg University Mainz, 55131, Mainz, Germany
| | - Muthuraman Muthuraman
- Section of Movement Disorders and Neurostimulation, Department of Neurology, Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg University Mainz, 55131, Mainz, Germany
| | - Sergiu Groppa
- Section of Movement Disorders and Neurostimulation, Department of Neurology, Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg University Mainz, 55131, Mainz, Germany.
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Lee KM, Coelho MA, Sern KR, Szumlinski KK. Homer2 within the central nucleus of the amygdala modulates withdrawal-induced anxiety in a mouse model of binge-drinking. Neuropharmacology 2017; 128:448-459. [PMID: 29109058 DOI: 10.1016/j.neuropharm.2017.11.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 10/17/2017] [Accepted: 11/02/2017] [Indexed: 02/07/2023]
Abstract
A history of binge-drinking decreases protein expression of the glutamate-related scaffolding protein Homer2 within the central nucleus of the amygdala (CEA), coinciding with behavioral signs of negative affect. To assess the functional relevance of this protein change for withdrawal-induced hyper-anxiety, adult (PND 56) and adolescent (PND 28) male C57BL/6J mice were administered an intra-CEA infusion of an adeno-associated viral vector (AAV) carrying either cDNA to express Homer2 (H2-cDNA) or GFP as control. Mice underwent 14 days of binge-drinking under multi-bottle, limited-access conditions and were assayed for behavioral signs of negative affect during withdrawal using the light-dark box, marble burying, and forced swim tests (FST). Following behavioral testing, all animals experienced 5 days of drinking to evaluate the effects of prior alcohol experience and Homer2 manipulation on subsequent alcohol consumption. During protracted (4 weeks) withdrawal, adolescent alcohol-experienced GFP controls showed increased signs of negative affect across all 3 assays, compared to water-drinking GFP animals, and also showed elevated alcohol consumption during the subsequent drinking period. Homer2-cDNA infusion in adolescent-onset alcohol-drinking animals was anxiolytic and reduced subsequent alcohol consumption. Conversely, Homer2-cDNA was anxiogenic and increased drinking in water-drinking adolescents. Unfortunately, the data from adult-onset alcohol-drinking animals were confounded by low alcohol consumption and negligible behavioral signs of anxiety. Nevertheless, the present results provide novel cause-effect evidence supporting a role for CEA Homer2 in the regulation of both basal anxiety and the time-dependent intensification of negative affective states in individuals with a history of binge-drinking during adolescence.
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Affiliation(s)
- K M Lee
- Department of Psychological and Brain Sciences, University of California Santa Barbara, Santa Barbara, 93106-9660 CA, USA
| | - M A Coelho
- Department of Psychological and Brain Sciences, University of California Santa Barbara, Santa Barbara, 93106-9660 CA, USA
| | - K R Sern
- Department of Psychological and Brain Sciences, University of California Santa Barbara, Santa Barbara, 93106-9660 CA, USA
| | - K K Szumlinski
- Department of Psychological and Brain Sciences, University of California Santa Barbara, Santa Barbara, 93106-9660 CA, USA; Department of Molecular, Cellular and Developmental Biology, The Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, 93106-9625 CA, USA.
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Affiliation(s)
- Paul J. Whalen
- Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
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Tagai K, Nagata T, Shinagawa S, Nemoto K, Inamura K, Tsuno N, Nakayama K. Correlation between both morphologic and functional changes and anxiety in Alzheimer's disease. Dement Geriatr Cogn Disord 2015; 38:153-60. [PMID: 24732302 DOI: 10.1159/000358822] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/17/2014] [Indexed: 12/13/2022] Open
Abstract
INTRODUCTION Although anxiety symptoms are often observed in Alzheimer's disease (AD), little attention has been paid to this symptom compared with other neuropsychiatric symptoms. METHODS Twenty-six patients with mild AD underwent both magnetic resonance imaging and single photon emission tomography with technetium-99m ethyl cysteinate dimer. Neuropsychiatric symptoms were evaluated using the Behavioral Pathology in Alzheimer's Disease Scale (Behave-AD). We investigated the relationship between anxiety and neuroimaging using Statistical Parametric Mapping 8 software. RESULTS The Behave-AD anxiety score was correlated with hyperperfusion in the bilateral anterior cingulate cortices and a reduction in the gray matter volume in the right precuneus and inferior parietal lobule. CONCLUSION Our results suggest that anxiety in AD could overlap with the neural correlates of anxiety disorders, and that the specific degeneration associated with AD might be associated with anxiety.
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Affiliation(s)
- Kenji Tagai
- Department of Psychiatry, Jikei University School of Medicine, Tokyo, Japan
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Psychosocial aspects of bruxism: the most paramount factor influencing teeth grinding. BIOMED RESEARCH INTERNATIONAL 2014; 2014:469187. [PMID: 25101282 PMCID: PMC4119714 DOI: 10.1155/2014/469187] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2014] [Accepted: 05/23/2014] [Indexed: 11/18/2022]
Abstract
In clinical practice, patients suffering from an occlusal parafunctional activity have increased. It can be observed that a negative influence of environment aggravates patient's health. The aim of this paper is to present the impact of environment and development of human civilization on the prevalence of bruxism and the correlation between them. The authors grasp the most relevant aspects of psychological and anthropological factors changing over time as well as their interactions and describe a relationship between chronic stress and bruxism. Current literature shows how contemporary lifestyle, working environment, diet, and habits influence the patient's psychoemotional situation and the way these factors affect the occluso-muscle condition.
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Kim JE, Dager SR, Lyoo IK. The role of the amygdala in the pathophysiology of panic disorder: evidence from neuroimaging studies. BIOLOGY OF MOOD & ANXIETY DISORDERS 2012; 2:20. [PMID: 23168129 PMCID: PMC3598964 DOI: 10.1186/2045-5380-2-20] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Accepted: 09/19/2012] [Indexed: 01/04/2023]
Abstract
Although the neurobiological mechanisms underlying panic disorder (PD) are not yet clearly understood, increasing amount of evidence from animal and human studies suggests that the amygdala, which plays a pivotal role in neural network of fear and anxiety, has an important role in the pathogenesis of PD. This article aims to (1) review the findings of structural, chemical, and functional neuroimaging studies on PD, (2) relate the amygdala to panic attacks and PD development, (3) discuss the possible causes of amygdalar abnormalities in PD, (4) and suggest directions for future research.
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Affiliation(s)
- Jieun E Kim
- Department of Radiology, School of Medicine, University of Washington, 1100 NE 45th St, Ste 555, WA 98105, Seattle, USA.
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Blackmon K, Barr WB, Carlson C, Devinsky O, DuBois J, Pogash D, Quinn BT, Kuzniecky R, Halgren E, Thesen T. Structural evidence for involvement of a left amygdala-orbitofrontal network in subclinical anxiety. Psychiatry Res 2011; 194:296-303. [PMID: 21803551 PMCID: PMC3544472 DOI: 10.1016/j.pscychresns.2011.05.007] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 05/03/2011] [Accepted: 05/21/2011] [Indexed: 11/23/2022]
Abstract
Functional neuroimaging implicates hyperactivity of amygdala-orbitofrontal circuitry as a common neurobiological mechanism underlying the development of anxiety. Less is known about anxiety-related structural differences in this network. In this study, a sample of healthy adults with no history of anxiety disorders completed a 3T MRI scan and self-report mood inventories. Post-processing quantitative MRI image analysis included segmentation and volume estimation of subcortical structures, which were regressed on anxiety inventory scores, with depression scores used to establish discriminant validity. We then used a quantitative vertex-based post-processing method to correlate (1) anxiety scores and (2) left amygdala volumes with cortical thickness across the whole cortical mantle. Left amygdala volumes predicted anxiety, with decreased amygdala volume associated with higher anxiety on both state and trait anxiety measures. A negative correlation between left amygdala volume and cortical thickness overlapped with a positive correlation between anxiety and cortical thickness in left lateral orbitofrontal cortex. These results suggest a structural anxiety network that corresponds with a large body of evidence from functional neuroimaging. Such findings raise the possibility that structural abnormalities may result in a greater vulnerability to anxiety or conversely that elevated anxiety symptoms may result in focal structural changes.
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Affiliation(s)
- Karen Blackmon
- Comprehensive Epilepsy Center, Department of Neurology, New York University, NY, NY, USA
| | - William B Barr
- Comprehensive Epilepsy Center, Department of Neurology, New York University, NY, NY, USA
| | - Chad Carlson
- Comprehensive Epilepsy Center, Department of Neurology, New York University, NY, NY, USA
| | - Orrin Devinsky
- Comprehensive Epilepsy Center, Department of Neurology, New York University, NY, NY, USA
| | - Jonathan DuBois
- Comprehensive Epilepsy Center, Department of Neurology, New York University, NY, NY, USA
| | - Daniel Pogash
- Comprehensive Epilepsy Center, Department of Neurology, New York University, NY, NY, USA
| | - Brian T Quinn
- Comprehensive Epilepsy Center, Department of Neurology, New York University, NY, NY, USA; Center for Neural Science, New York University, NY, NY, USA
| | - Ruben Kuzniecky
- Comprehensive Epilepsy Center, Department of Neurology, New York University, NY, NY, USA
| | - Eric Halgren
- Multimodal Imaging Laboratory, University of California, San Diego, CA, USA
| | - Thomas Thesen
- Comprehensive Epilepsy Center, Department of Neurology, New York University, NY, NY, USA; Multimodal Imaging Laboratory, University of California, San Diego, CA, USA.
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Smirnov MS, Kiyatkin EA, Smith Y. Cocaine action on peripheral, non-monoamine neural substrates as a trigger of electroencephalographic desynchronization and electromyographic activation following i.v. administration in freely moving rats. Neuroscience 2010; 165:500-14. [PMID: 19861149 PMCID: PMC2794948 DOI: 10.1016/j.neuroscience.2009.10.037] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Revised: 09/22/2009] [Accepted: 10/16/2009] [Indexed: 11/30/2022]
Abstract
Many important physiological, behavioral and subjective effects of i.v. cocaine (COC) are exceptionally rapid and transient, suggesting a possible involvement of peripheral neural substrates in their triggering. In the present study, we used high-speed electroencephalographic (EEG) and electromyographic (EMG) recordings (4-s resolution) in freely moving rats to characterize the central electrophysiological effects of i.v. COC at low doses within a self-administration range (0.25-1.0 mg/kg). We found that COC induces rapid, strong, and prolonged desynchronization of cortical EEG (decrease in alpha and increase in beta and gamma activity) and activation of the neck EMG that begin within 2-6 s following the start of a 10-s injection; immediate components of both effects were dose-independent. The rapid effects of COC were mimicked by i.v. COC methiodide (COC-MET), a derivative that cannot cross the blood-brain barrier. At equimolar doses (0.33-1.33 mg/kg), COC-MET had equally fast and strong effects on EEG and EMG total powers, decreasing alpha and increasing beta and gamma activities. Rapid EEG desynchronization and EMG activation was also induced by i.v. procaine, a structurally similar, short-acting local anesthetic with virtually no effects on monoamine uptake; at equipotential doses (1.25-5.0 mg/kg), these effects were weaker and shorter in duration than those of COC. Surprisingly, i.v. saline injection delivered during slow-wave sleep (but not during quiet wakefulness) also induced a transient EEG desynchronization but without changes in EMG and motor activity; these effects were significantly weaker and much shorter than those induced by all tested drugs. These data suggest that in awake animals, i.v. COC induces rapid cortical activation and a subsequent motor response via its action on peripheral non-monoamine neural elements, involving neural transmission via visceral sensory pathways. By providing a rapid neural signal and triggering neural activation, such an action might play a crucial role in the sensory effects of COC, thus contributing to the learning and development of drug-taking behavior.
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Affiliation(s)
- Michael S. Smirnov
- Behavioral Neuroscience Branch, National Institute on Drug Abuse – Intramural Research Program, National Institutes of Health, DHHS, 333 Cassell Drive, Baltimore, Maryland 21224
| | - Eugene A. Kiyatkin
- Behavioral Neuroscience Branch, National Institute on Drug Abuse – Intramural Research Program, National Institutes of Health, DHHS, 333 Cassell Drive, Baltimore, Maryland 21224
| | - Y. Smith
- Behavioral Neuroscience Branch, National Institute on Drug Abuse – Intramural Research Program, National Institutes of Health, DHHS, 333 Cassell Drive, Baltimore, Maryland 21224
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Abstract
Anxiety disorders are a significant problem in the community, and recent neuroimaging research has focused on determining the brain circuits that underlie them. Research on the neurocircuitry of anxiety disorders has its roots in the study of fear circuits in animal models and the study of brain responses to emotional stimuli in healthy humans. We review this research, as well as neuroimaging studies of anxiety disorders. In general, these studies have reported relatively heightened amygdala activation in response to disorder-relevant stimuli in post-traumatic stress disorder, social phobia, and specific phobia. Activation in the insular cortex appears to be heightened in many of the anxiety disorders. Unlike other anxiety disorders, post-traumatic stress disorder is associated with diminished responsivity in the rostral anterior cingulate cortex and adjacent ventral medial prefrontal cortex. Additional research will be needed to (1) clarify the exact role of each component of the fear circuitry in the anxiety disorders, (2) determine whether functional abnormalities identified in the anxiety disorders represent acquired signs of the disorders or vulnerability factors that increase the risk of developing them, (3) link the findings of functional neuroimaging studies with those of neurochemistry studies, and (4) use functional neuroimaging to predict treatment response and assess treatment-related changes in brain function.
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Kiyatkin EA, Smirnov MS. Rapid EEG desynchronization and EMG activation induced by intravenous cocaine in freely moving rats: a peripheral, nondopamine neural triggering. Am J Physiol Regul Integr Comp Physiol 2009; 298:R285-300. [PMID: 19939972 DOI: 10.1152/ajpregu.00628.2009] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Many important physiological, behavioral, and psychoemotional effects of intravenous (IV) cocaine (COC) are too fast and transient compared with pharmacokinetic predictions, suggesting a possible involvement of peripheral neural mechanisms in their triggering. In the present study, we examined changes in cortical electroencephalogram (EEG) and neck electromyogram (EMG) induced in freely moving rats by IV COC administration at low, reinforcing doses (0.25-1.0 mg/kg) and compared them with those induced by an auditory stimulus and IV COC methiodide, which cannot cross the blood-brain barrier. We found that COC induces rapid, strong, and prolonged EEG desynchronization, associated with decrease in alpha and increase in beta and gamma activities, and EMG activation and that both begin within 2-6 s following the start of a 10-s injection; immediate components of this effect were dose independent. The rapid COC-induced changes in EEG and EMG resembled those induced by an auditory stimulus; the latter effects had shorter onset latencies and durations and were fully blocked during urethane anesthesia. Although urethane anesthesia completely blocked COC-induced EMG activation and rapid components of EEG response, COC still induced EEG desynchronization that was much weaker, greatly delayed (approximately 60 s), and associated with tonic decreases in delta and increases in alpha, beta, and gamma activities. Surprisingly, IV saline delivered during slow-wave sleep (but not quite wakefulness) also induced a transient EEG desynchronization but without changes in EMG activity; these effects were also fully blocked during anesthesia. Peripherally acting COC methiodide fully mimicked rapid EEG and EMG effects of regular COC, but the effects at an equimolar dose were less prolonged than those with regular COC. These data suggest that in awake animals IV COC, like somato-sensory stimuli, induces cortical activation and a subsequent motor response via its action on peripheral neural elements and involving rapid neural transmission. By providing a rapid neural signal and triggering transient neural activation, such an action might play a crucial role in the sensory effects of COC, thus contributing to the learning and development of drug-taking behavior.
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Affiliation(s)
- Eugene A Kiyatkin
- Behavioral Neuroscience Branch, National Institute on Drug Abuse-Intramural Research Program, National Institutes of Health, DHHS, 333 Cassell Dr., Baltimore, MD 21224, USA.
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Abstract
Negative feedback, either internal or external, is a fundamental guide to human learning and performance. The neural system that underlies the monitoring of performance and the adjustment of behavior has been subject to multiple neuroimaging investigations that uniformly implicate the anterior cingulate cortex and other prefrontal structures as crucial to these executive functions. The present article describes a series of experiments that employed event-related potentials to study a variety of processes associated with internal or external feedback. Three medial-frontal negativities (error-related negativity, correct-response negativity, feedback-related negativity) are highlighted, each of which plays an important role in the monitoring and dynamic adjustment of behavior. Extensions of basic research on these ERPs to questions relevant to clinical-science are also provided.
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Affiliation(s)
- Robert F Simons
- Department of Psychology, University of Delaware, Newark, DE 19716, USA.
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Adinoff B, Devous MD, Cooper DC, Best SE, Harris TS, Williams MJ. Neural response to lidocaine in healthy subjects. Psychiatry Res 2009; 173:135-42. [PMID: 19560905 PMCID: PMC2771760 DOI: 10.1016/j.pscychresns.2009.03.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2008] [Revised: 02/24/2009] [Accepted: 03/04/2009] [Indexed: 11/13/2022]
Abstract
Recent studies suggest that some of cocaine's central nervous system (CNS) effects may be mediated through its sodium channel inhibiting local anesthetic properties. Local anesthetics that lack cocaine's strong affinity for the dopamine transporter (DAT) also produce sensory and mood effects, further suggesting a role for this neural pathway. Due to an absence of affinity at the DAT, the local anesthetic lidocaine may offer the potential to assess sodium channel activity in vivo in humans. To assess the utility of lidocaine as a CNS probe, we determined regional cerebral blood flow (rCBF) with single photon emission computed tomography (SPECT) following the intravenous administration of lidocaine (0.5 mg/kg) and compared this response to procaine (0.5 mg/kg and 1.0 mg/kg), a local anesthetic with partial affinity for the DAT, and saline. Infusions were administered in nine healthy female controls over a 10-day period with at least 2 days between each scan. Increased rCBF was observed following lidocaine, relative to saline, in the insula, caudate, thalamus, and posterior cingulate. Decreased rCBF was detected in a different region of the posterior cingulate. In general, increases in rCBF were more marked following lidocaine relative to procaine. Mood and sensory changes following lidocaine were limited and significantly less than those induced by either dose of procaine. There were no significant changes in blood pressure or heart rate following either medication. These findings suggest that lidocaine can be safely used to assess sodium channel function in persons with addictive and other psychiatric disorders.
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Affiliation(s)
- Bryon Adinoff
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, United States.
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Electrophysiological evaluation of the time-course of dopamine uptake inhibition induced by intravenous cocaine at a reinforcing dose. Neuroscience 2007; 151:824-35. [PMID: 18191902 DOI: 10.1016/j.neuroscience.2007.11.034] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Revised: 11/19/2007] [Accepted: 11/28/2007] [Indexed: 11/23/2022]
Abstract
Cocaine effectively inhibits dopamine (DA) uptake and this action appears to be the primary cause for increased DA transmission following systemic cocaine administration. Although this action had been reliably demonstrated in vivo with cocaine at high doses, data on the extent and the time-course of DA uptake inhibition induced by i.v. cocaine at low, reinforcing doses remain controversial. To clarify this issue, we examined how cocaine affects striatal neuronal responses to repeated iontophoretic DA applications in urethane-anesthetized rats. Because most striatal neurons during anesthesia have low, sporadic activity, DA tests were performed on cells tonically activated by continuous glutamate application. DA phasically decreased the activity of most dorsal and ventral striatal neurons; these responses in control conditions (i.v. saline) were current (dose) -dependent and remained highly stable following repeated DA applications at the same currents. DA also consistently decreased the activity of striatal neurons after i.v. cocaine (1 mg/kg); the magnitude of DA-induced inhibition slowly increased from approximately 5 min, became significantly larger from approximately 9 min, and peaked at 13-15 min after a single i.v. injection. Then, the difference in the DA response slowly decreased toward the pre-cocaine baseline. A similar enhancement of DA induced-inhibition was also seen after i.p. cocaine administration at a high dose (15 mg/kg). In this case, the DA response became significantly stronger at 7-9 min and remained enhanced vs. a pre-drug control up to 24-26 min after the injection. Both regimens of cocaine treatment did not result in evident changes in either onset or offset of the DA-induced inhibitions. Our data confirm that cocaine at low, reinforcing doses inhibits DA uptake, resulting in potentiation of DA-induced neuronal inhibitions, but they suggest that this effect is relatively weak and delayed from the time of i.v. injection. These slow and prolonged effects of i.v. cocaine on DA-induced neuronal responses are consistent with previous binding and our electrochemical evaluations of DA uptake, presumably reflecting the total time necessary for i.v.-delivered cocaine to reach brain microvessels, cross the blood-brain barrier, passively diffuse within brain tissue, interact with the DA transporters, and finally inhibit DA uptake.
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Kiyatkin EA, Brown PL. I.v. cocaine induces rapid, transient excitation of striatal neurons via its action on peripheral neural elements: single-cell, iontophoretic study in awake and anesthetized rats. Neuroscience 2007; 148:978-95. [PMID: 17706878 PMCID: PMC2084066 DOI: 10.1016/j.neuroscience.2007.07.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2007] [Revised: 06/29/2007] [Accepted: 07/12/2007] [Indexed: 11/17/2022]
Abstract
Cocaine's (COC) direct interaction with the dopamine (DA) transporter is usually considered the most important action underlying the psychomotor stimulant and reinforcing effects of this drug. However, some physiological, behavioral and psycho-emotional effects of COC are very rapid and brief and they remain intact during DA receptor blockade, suggesting possible involvement of peripheral non-DA neural mechanisms. To assess this issue, single-unit recording with microiontophoresis was used to examine changes in impulse activity of dorsal and ventral striatal neurons to i.v. COC (0.25-0.5 mg/kg) in the same rats under two conditions: awake with DA receptor blockade and anesthetized with urethane. In the awake preparation approximately 70% striatal neurons showed rapid and transient (latency approximately 6 s, duration approximately 15 s) COC-induced excitations. These effects were stronger in ventral than dorsal striatum. During anesthesia, these phasic effects were fully blocked and COC slowly decreased neuronal discharge rate. Cocaine-methiodide (COC-M), a derivative that cannot cross the blood-brain barrier, also caused phasic excitations in the awake, but not anesthetized condition. In contrast to regular COC, COC-M had no tonic effect on discharge rate in either preparation. Most striatal neurons that were phasically excited by both COC forms also showed short-latency excitations during tail-touch and tail-pinch in the awake preparation, an effect strongly attenuated during anesthesia. Finally, most striatal neurons that in awake conditions were phasically excited by somato-sensory stimuli and COC salts were also excited by iontophoretic glutamate (GLU). Although striatal neurons were sensitive to GLU in both preparations, the response magnitude at the same GLU current was higher in awake than anesthetized conditions. These data suggest that in awake animals i.v. COC, like somato-sensory stimuli, transiently excites striatal neurons via its action on peripheral neural elements and rapid neural transmission. While the nature of these neuronal elements needs to be clarified using other analytical techniques, they might involve voltage-gated K(+) and Na(+) channels, which have a high affinity for COC and are located on terminals of visceral sensory nerves that densely innervate peripheral vessels. Therefore, along with direct action on specific brain substrates, central excitatory effects of COC may occur via indirect action, involving afferents of visceral sensory nerves and rapid neural transmission. By providing a rapid sensory signal and triggering transient neural activation, such a peripherally triggered action might play a crucial role in the sensory effects of COC, thus contributing to learning and development of drug-taking behavior.
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Affiliation(s)
- E A Kiyatkin
- Behavioral Neuroscience Branch, National Institute on Drug Abuse-Intramural Research Program, National Institutes of Health, DHHS, 5500 Nathan Shock Drive, Baltimore, MD 21224, USA.
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Olsén L, Ingvast-Larsson C, Broström H, Larsson P, Tjälve H. Clinical signs and etiology of adverse reactions to procaine benzylpenicillin and sodium/potassium benzylpenicillin in horses. J Vet Pharmacol Ther 2007; 30:201-7. [PMID: 17472651 DOI: 10.1111/j.1365-2885.2007.00851.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Case reports of 59 horses reacting adversely to procaine benzylpenicillin or to sodium or potassium benzylpenicillin in Sweden in 2003-2005 were obtained through contacts with horse-owners. For the assessment of the reports, various parameters were evaluated, such as the times to the reactions, information on previous penicillin treatment, the clinical signs and the actions taken in the reacting horses. Among the reports, two horses had received sodium or potassium benzylpenicillin intravenously, whereas the remaining 57 horses had been treated with procaine benzylpenicillin intramuscularly. Allergy may underlie the adverse reactions in the horses given sodium and potassium benzylpenicillin, and in a few of the horses given procaine benzylpenicillin. However, in most horses in the latter group, the clinical signs may be due to the toxic effects of procaine. In these horses, the dominating clinical signs were locomotor and behavioral changes. Some risk factors may enhance the probability that horses react to procaine. One is repeated injections, which increase the likelihood of intravascular administration and also may increase the sensitivity to procaine due to neuronal sensitization (kindling). Procaine is rapidly hydrolyzed by plasma esterases to nontoxic metabolites. When high amounts of procaine enter the circulation, the hydrolyzing capacity may be exceeded and toxicity occurs. Analyses of plasma esterases from reacting horses showed lower activity than in nonreacting control horses. Low esterase activity may increase the possibility of procaine toxicity and constitute another risk factor.
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Affiliation(s)
- L Olsén
- Division of Pathology, Pharmacology and Toxicology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden.
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18
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Gilles C, Luthringer R. Pharmacological models in healthy volunteers: their use in the clinical development of psychotropic drugs. J Psychopharmacol 2007; 21:272-82. [PMID: 17591655 DOI: 10.1177/0269881107077733] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Animal models of diseases are widely used in the preclinical phase of drug development. They have a place in early human clinical psychopharmacology as well, in order to get early clues that contribute to establish the proof of concept (POC) already in healthy volunteers (HV). Different types of models are available (pharmacological or non-pharmacological provocation, models based on age-related characteristics). This review is focused on pharmacological models in HV, with the aim to identify the main issues raised by their use in pharmaceutical trials. The available models unevenly fulfil the requirements of face validity, sufficient response rate, test-retest consistence and responsiveness to reference drugs. Most of them have been developed in the purpose of pathophysiology studies, using rating instruments validated for clinical practice. Substantial progress could be made by adapting models to the specific requirements of pharmaceutical trials, including wider use of biomarkers. Characteristics that make models, as well as biomarkers, suitabLe for use in drug development are proposed. Despite obvious limitations, human models can significantly enhance the way phase I studies contribute to establish the POC, provided they are integrated into adapted phase I development plans. Their use as industrial tools for drug evaluation requires specific, dedicated development.
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Carroll I. Intravenous lidocaine for neuropathic pain: Diagnostic utility and therapeutic efficacy. Curr Pain Headache Rep 2007; 11:20-4. [PMID: 17214917 DOI: 10.1007/s11916-007-0017-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Lidocaine is a use-dependent sodium channel blocker that produces analgesia when administered intravenously to patients with neuropathic pain. This article reviews the role and limitations of intravenous lidocaine infusions for neuropathic pain. Lidocaine infusions rarely provide relief that persists significantly beyond the duration of the infusion. Diagnostically, systemic lidocaine may help establish the presence of neuropathic pain and the responsivity to oral sodium channel blockade. However, the data supporting diagnostic infusions remain sparse. Therapeutically, infusions should generally be restricted to patients with neuropathic pain who are unable to take oral medication.
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Affiliation(s)
- Ian Carroll
- Stanford University School of Medicine, 780 Welch Road, Suite 208E, Palo Alto, CA 94034, USA.
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20
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Nagai M, Kishi K, Kato S. Insular cortex and neuropsychiatric disorders: A review of recent literature. Eur Psychiatry 2007; 22:387-94. [PMID: 17416488 DOI: 10.1016/j.eurpsy.2007.02.006] [Citation(s) in RCA: 239] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2006] [Revised: 02/04/2007] [Accepted: 02/16/2007] [Indexed: 10/23/2022] Open
Abstract
AbstractThe insular cortex is located in the centre of the cerebral hemisphere, having connections with the primary and secondary somatosensory areas, anterior cingulate cortex, amygdaloid body, prefrontal cortex, superior temporal gyrus, temporal pole, orbitofrontal cortex, frontal and parietal opercula, primary and association auditory cortices, visual association cortex, olfactory bulb, hippocampus, entorhinal cortex, and motor cortex. Accordingly, dense connections exist among insular cortex neurons. The insular cortex is involved in the processing of visceral sensory, visceral motor, vestibular, attention, pain, emotion, verbal, motor information, inputs related to music and eating, in addition to gustatory, olfactory, visual, auditory, and tactile data. In this article, the literature on the relationship between the insular cortex and neuropsychiatric disorders was summarized following a computer search of the Pub-Med database. Recent neuroimaging data, including voxel based morphometry, PET and fMRI, revealed that the insular cortex was involved in various neuropsychiatric diseases such as mood disorders, panic disorders, PTSD, obsessive-compulsive disorders, eating disorders, and schizophrenia. Investigations of functions and connections of the insular cortex suggest that sensory information including gustatory, olfactory, visual, auditory, and tactile inputs converge on the insular cortex, and that these multimodal sensory information may be integrated there.
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Affiliation(s)
- M Nagai
- Department of Internal Medicine, Shobara Red Cross Hospital, Hiroshima, Japan.
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21
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Brown PL, Kiyatkin EA. The role of peripheral Na(+) channels in triggering the central excitatory effects of intravenous cocaine. Eur J Neurosci 2007; 24:1182-92. [PMID: 16930444 DOI: 10.1111/j.1460-9568.2006.05001.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
While alterations in dopamine (DA) uptake appear to be a critical mechanism underlying locomotor and reinforcing effects of cocaine (COC), many centrally mediated physiological and affective effects of this drug are resistant to DA receptor blockade and are expressed more quickly following an intravenous (i.v.) injection than expected based on the dynamics of drug concentration in the brain. Because COC is also a potent local anesthetic, its rapid action on Na+ channels may be responsible for triggering these effects. We monitored temperatures in the nucleus accumbens, temporal muscle and skin together with conventional locomotion during a single i.v. injection of COC (1 mg/kg), procaine (PRO, 5 mg/kg; equipotential anesthetic dose), a short-acting local anesthetic drug that, like COC, interacts with Na+ channels, and cocaine methiodide (COC-MET, 1.31 mg/kg, equimolar dose), a quaternary COC derivative that is unable to cross the blood-brain barrier. In this way, we explored not only the importance of Na+ channels in general, but also the importance of central vs. peripheral Na+ channels specifically. COC induced locomotor activation, temperature increase in the brain and muscle, and a biphasic temperature fluctuation in skin. Though PRO did not induce locomotor activation, it mimicked, to a greater degree, the temperature effects of COC. Therefore, Na+ channels appear to be a key substrate for COC-induced temperature fluctuations in the brain and periphery. Similar to PRO, COC-MET had minimal effects on locomotion, but mimicked COC in its ability to increase brain and muscle temperature, and induce transient skin hypothermia. It appears therefore that COC's interaction with peripherally located Na+ channels triggers its central excitatory effects manifested by brain temperature increase, thereby playing a major role in drug sensing and possibly contributing to COC reinforcement.
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Affiliation(s)
- P Leon Brown
- Cellular Neurobiology Branch, National Institute on Drug Abuse--Intramural Research Program, National Institutes of Health, DHHS, 333 Cassell Drive, Baltimore, MD 21224, USA
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22
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Kiyatkin EA, Brown PL. The role of peripheral and central sodium channels in mediating brain temperature fluctuations induced by intravenous cocaine. Brain Res 2006; 1117:38-53. [PMID: 16956595 PMCID: PMC1847334 DOI: 10.1016/j.brainres.2006.08.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2006] [Revised: 07/27/2006] [Accepted: 08/04/2006] [Indexed: 11/26/2022]
Abstract
While cocaine's interaction with the dopamine (DA) transporter and subsequent increase in DA transmission are usually considered key factors responsible for its locomotor stimulatory and reinforcing properties, many centrally mediated physiological and psychoemotional effects of cocaine are resistant to DA receptor blockade, suggesting the importance of other non-DA mechanisms. To explore the role of cocaine's interaction with Na+ channels, rats were used to compare locomotor stimulatory and temperature (NAcc, temporal muscle and skin) effects of repeated iv injections of cocaine (1 mg/kg) with those induced by procaine (PRO 5 mg/kg), a short-acting local anesthetic with negligible effect on the DA transporter, and cocaine methiodide (COC-MET 1.31 mg/kg), a quaternary cocaine derivative that is unable to cross the blood-brain barrier. While PRO, unlike cocaine, did not induce locomotor activation, it mimicked cocaine in its ability to increase brain temperature following the initial injection and to induce biphasic, down-up fluctuations following repeated injections. This similarity suggests that both these effects of cocaine may be driven by its action on Na+ channels, a common action of both drugs. While COC-MET also did not affect locomotor activity, it shared with cocaine and PRO their ability to increase brain temperature but failed to induce temperature decreases after repeated injections. These findings point toward activation of peripheral Na+ channels as the primary mechanism of rapid excitatory effects of cocaine and inhibition of centrally located Na+ channels as the primary mechanism for transient inhibitory effects of cocaine. DA receptor blockade (SCH23390+eticlopride) fully eliminated locomotor stimulatory and temperature-increasing effects of cocaine, but its temperature-decreasing effects remained intact. Surprisingly, DA receptor blockade also altered the temperature fluctuations caused by PRO and COC-MET, suggesting that some of the central effects triggered via Na+ channels are in fact DA-dependent. Finally, repeated administration of PRO to animals that had previous cocaine experience led to conditioned locomotion and potentiated temperature-increasing effects of this drug. It appears, therefore, that, in addition to the central effects of cocaine mediated via interaction with the DA transporter and potentiation of DA uptake, interaction with peripheral and central Na+ channels is important for the initial physiological and, perhaps, affective effects of cocaine, likely contributing to the unique abuse potential of this drug.
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Affiliation(s)
- Eugene A Kiyatkin
- Cellular Neurobiology Branch, National Institute on Drug Abuse-Intramural Research Program, National Institutes of Health, DHHS, 333 Cassell Drive, Baltimore, MD 21224, USA.
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23
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Moser JS, Hajcak G, Simons RF. The effects of fear on performance monitoring and attentional allocation. Psychophysiology 2005; 42:261-8. [PMID: 15943679 DOI: 10.1111/j.1469-8986.2005.00290.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Evidence from event-related potential (ERP) studies indicates abnormal error processing and attentional allocation in "trait"-anxious individuals. However, few studies have been conducted that evaluate relevant ERP components during the induction of an anxious state (i.e., fear). In the present study, ERPs were measured in 16 undergraduates during control and fear induction conditions to examine the effects of fear on error processing and attentional allocation. Despite comparable performance in both experimental conditions, the ERP data indicated reductions in attentional allocation and error salience during fear induction. Fear did not appear to directly alter early error processing, as indicated by the error-related negativity, however. The implication of these results for understanding how trait and state anxiety may affect error processing and attentional allocation are discussed.
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Affiliation(s)
- Jason S Moser
- Department of Psychology, University of Delaware, Newark, DE 19716, USA
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Benson BE, Carson RE, Kiesewetter DO, Herscovitch P, Eckelman WC, Post RM, Ketter TA. A potential cholinergic mechanism of procaine's limbic activation. Neuropsychopharmacology 2004; 29:1239-50. [PMID: 14997171 DOI: 10.1038/sj.npp.1300404] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The local anesthetic procaine, when administered to humans intravenously (i.v.), yields brief intense emotional and sensory experiences, and concomitant increases in anterior paralimbic cerebral blood flow, as measured by positron emission tomography (PET). Procaine's high muscarinic affinity, together with the distribution of muscarinic receptors that overlaps with brain regions activated by procaine, suggests a muscarinic contribution to procaine's emotional and sensory effects. This study evaluates the effects of procaine on cerebral muscarinic cholinergic receptors in the anesthetized rhesus monkey. Whole brain and regional muscarinic receptor binding was measured before and after procaine administration on the same day in three anesthetized rhesus monkeys with PET and the radiotracer 3-(3-(3[18F]fluoropropylthio)-1,2,5-thiadiazol-4-yl)-1,2,5,6-tetrahydro-1-methylpyridine ([18F]FP-TZTP), a cholinergic ligand that has preferential binding to muscarinic (M(2)) receptors. On separate days each animal received six different doses of i.v. procaine in a randomized fashion. Procaine blocked up to approximately 90% of [18F]FP-TZTP specific binding globally in a dose-related manner. There were no regional differences in procaine's inhibitory concentration for 50% blockade (IC50) for [18F]FP-TZTP. Tracer delivery, which was highly correlated to cerebral blood flow in previous monkey studies, was significantly increased at all doses of procaine with the greatest increases occurring near procaine's IC50 for average cortex. Furthermore, anterior limbic regions showed greater increases in tracer delivery than nonlimbic regions. Procaine has high affinity to muscarinic M2 receptors in vivo in the rhesus monkey. This, as well as a preferential increase of tracer delivery to paralimbic regions, suggests that action at these receptors could contribute to i.v. procaine's emotional and sensory effects in man. These findings are consistent with other evidence of cholinergic modulation of mood and emotion.
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Affiliation(s)
- Brenda E Benson
- Biological Psychiatry Branch, NIMH, NIH, Bethesda, MD 20892-1272, USA.
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25
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Leong MS, Solvason HB. Case report: limbic system activation by intravenous lidocaine in a patient with a complex regional pain syndrome and major depression. PAIN MEDICINE 2004; 1:358-61. [PMID: 15101882 DOI: 10.1046/j.1526-4637.2000.00038.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Intravenous lidocaine is used to treat various neuropathic pain states. Systemic local anesthetics have been reported to cause behavioral alteration via limbic system activation. This case report describes a dramatic behavioral change in a patient receiving intravenous lidocaine and suggests a possible use of lidocaine to discriminate somatic and affective pain characteristics.
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Affiliation(s)
- M S Leong
- Department of Anesthesiology, Pain Management Services, Stanford University, School of Medicine, CA 94305-5117, USA.
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26
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Crippa JADS, Zuardi AW, Garrido GEJ, Wichert-Ana L, Guarnieri R, Ferrari L, Azevedo-Marques PM, Hallak JEC, McGuire PK, Filho Busatto G. Effects of cannabidiol (CBD) on regional cerebral blood flow. Neuropsychopharmacology 2004; 29:417-26. [PMID: 14583744 DOI: 10.1038/sj.npp.1300340] [Citation(s) in RCA: 185] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Animal and human studies have suggested that cannabidiol (CBD) may possess anxiolytic properties, but how these effects are mediated centrally is unknown. The aim of the present study was to investigate this using functional neuroimaging. Regional cerebral blood flow (rCBF) was measured at rest using (99m)Tc-ECD SPECT in 10 healthy male volunteers, randomly divided into two groups of five subjects. Each subject was studied on two occasions, 1 week apart. In the first session, subjects were given an oral dose of CBD (400 mg) or placebo, in a double-blind procedure. SPECT images were acquired 90 min after drug ingestion. The Visual Analogue Mood Scale was applied to assess subjective states. In the second session, the same procedure was performed using the drug that had not been administered in the previous session. Within-subject between-condition rCBF comparisons were performed using statistical parametric mapping (SPM). CBD significantly decreased subjective anxiety and increased mental sedation, while placebo did not induce significant changes. Assessment of brain regions where anxiolytic effects of CBD were predicted a priori revealed two voxel clusters of significantly decreased ECD uptake in the CBD relative to the placebo condition (p<0.001, uncorrected for multiple comparisons). These included a medial temporal cluster encompassing the left amygdala-hippocampal complex, extending into the hypothalamus, and a second cluster in the left posterior cingulate gyrus. There was also a cluster of greater activity with CBD than placebo in the left parahippocampal gyrus (p<0.001). These results suggest that CBD has anxiolytic properties, and that these effects are mediated by an action on limbic and paralimbic brain areas.
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Affiliation(s)
- José Alexandre de Souza Crippa
- Department of Neuropsychiatry and Medical Psychology, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil
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27
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Nitschke JB, Nelson EE, Rusch BD, Fox AS, Oakes TR, Davidson RJ. Orbitofrontal cortex tracks positive mood in mothers viewing pictures of their newborn infants. Neuroimage 2004; 21:583-92. [PMID: 14980560 DOI: 10.1016/j.neuroimage.2003.10.005] [Citation(s) in RCA: 247] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2003] [Revised: 10/06/2003] [Accepted: 10/06/2003] [Indexed: 11/21/2022] Open
Abstract
Positive affect elicited in a mother toward her newborn infant may be one of the most powerful and evolutionarily preserved forms of positive affect in the emotional landscape of human behavior. This study examined the neurobiology of this form of positive emotion and in so doing, sought to overcome the difficulty of eliciting robust positive affect in response to visual stimuli in the physiological laboratory. Six primiparous human mothers with no indications of postpartum depression brought their infants into the laboratory for a photo shoot. Approximately 6 weeks later, they viewed photographs of their infant, another infant, and adult faces during acquisition of functional magnetic resonance images (fMRI). Mothers exhibited bilateral activation of the orbitofrontal cortex (OFC) while viewing pictures of their own versus unfamiliar infants. While in the scanner, mothers rated their mood more positively for pictures of their own infants than for unfamiliar infants, adults, or at baseline. The orbitofrontal activation correlated positively with pleasant mood ratings. In contrast, areas of visual cortex that also discriminated between own and unfamiliar infants were unrelated to mood ratings. These data implicate the orbitofrontal cortex in a mother's affective responses to her infant, a form of positive emotion that has received scant attention in prior human neurobiological studies. Furthermore, individual variations in orbitofrontal activation to infant stimuli may reflect an important dimension of maternal attachment.
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Affiliation(s)
- Jack B Nitschke
- W.M. Keck Laboratory for Functional Brain Imaging and Behavior and Laboratory for Affective Neuroscience, Departments of Psychiatry and Psychology, University of Wisconsin, Madison, WI 53705-2280, USA.
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28
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Brambilla P, Harenski K, Nicoletti M, Sassi RB, Mallinger AG, Frank E, Kupfer DJ, Keshavan MS, Soares JC. MRI investigation of temporal lobe structures in bipolar patients. J Psychiatr Res 2003; 37:287-95. [PMID: 12765851 DOI: 10.1016/s0022-3956(03)00024-4] [Citation(s) in RCA: 176] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Previous anatomical MRI studies have suggested abnormalities in amygdala volumes in bipolar disorder, whereas hippocampus, temporal lobe (TL), and superior temporal gyri (STG) measures have been reported to be normal. This study further investigated the existence of anatomical abnormalities in these brain structures in bipolar subjects, to attempt to replicate previously reported findings. Twenty-four DSM-IV bipolar patients (mean age+/-S.D.=35+/-10 years) and 36 healthy controls (mean age+/-S.D.=37+/-10 years) were studied. 3D SPGR images were obtained with a 1.5T-GE Signa magnet (TR=25 ms, TE=5 ms, FOV=24 cm, slice-thickness=1.5 mm, matrix-size=256 x 192). Volumetric measurements of TL, hippocampus, amygdala, and STG were performed blindly, with a semi-automated software. Bipolar patients had significantly larger left amygdala volumes compared with controls (mean volumes+/-S.D.=2.57+/-0.69 vs. 2.17+/-0.58 ml, respectively; ANCOVA, age, gender, ICV as covariates; F=4.42, df=1/55, P=0.04). The volumes of the other temporal lobe structures did not differ significantly between the two groups (ANCOVA, age, gender, and ICV as covariates, P>0.05). Our findings of enlarged left amygdala in bipolar patients are in agreement with prior MRI studies, suggesting that abnormalities in this brain structure may be implicated in pathophysiology of the illness. Longitudinal studies in high-risk offspring and first-episode patients will be needed to examine whether such abnormalities precede the appearance of symptoms, or whether they may appear subsequently as a result of illness course.
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Affiliation(s)
- Paolo Brambilla
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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Adinoff B, Devous MD, Best SE, Chandler P, Alexander D, Payne K, Harris TS, Williams MJ. Gender differences in limbic responsiveness, by SPECT, following a pharmacologic challenge in healthy subjects. Neuroimage 2003; 18:697-706. [PMID: 12667847 DOI: 10.1016/s1053-8119(03)00008-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Limbic system functioning is integral to the control and modulation of affect, motivation, reward, and memory. Neuropsychiatric disturbances involving disruptions in these cognitive and emotional dimensions exhibit different prevalence rates for men and women. Gender-specific differences in this integrated brain area may therefore be important in understanding both normal behavioral functioning and the etiologic underpinnings of neuropsychiatric disorders. To further explore such differences in limbic system function, we assessed regional cerebral blood flow, by SPECT, in men and women following the administration of procaine. Procaine is a local anesthetic that preferentially stimulates limbic structures. Psychiatrically and medically healthy, age-matched women (n = 15, 33.2 +/- 6.9 years) and men (n = 15, 32.8 +/- 6.9 years) were administered 1.38 mg/kg procaine or saline intravenously in two separate sessions. Using voxel-based analyses (P < 0.001), males significantly activated the bilateral insular cortex following procaine, whereas females more strongly activated the bilateral anterior and mesial temporal cortex. Both groups demonstrated significant anterior cingulate activation. Subjective responses to procaine did not significantly differ between the men and women. To our knowledge, this is the first report demonstrating gender-specific responses in limbic activation following a pharmacologic challenge. These findings suggest that men and women can activate different limbic structures following the same provocative pharmacologic stimulus, despite sharing a similar subjective experience. Studies assessing pharmacologic challenges of limbic system structures should consider gender as a critical variable in assessing biologic responsiveness.
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Affiliation(s)
- Bryon Adinoff
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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Adinoff B, Devous MD, Best SE, Alexander D, Kelly Payne J, Williams M. Dose-response measures of rCBF and subjective changes following procaine in healthy female volunteers. Psychiatry Res 2002; 114:123-35. [PMID: 12113895 DOI: 10.1016/s0925-4927(02)00008-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The intravenous administration of procaine shows relatively specific activation of limbic structures. Several investigators have utilized this property of procaine to probe limbic system dysfunction in neuropsychiatric disorders. The dose of procaine utilized in human studies varies significantly, however, and the optimal dose of procaine as a limbic probe has not been demonstrated. In two 10-individual groups of healthy female volunteers, we assessed the regional cerebral blood flow (rCBF) response, by single-photon emission computed tomography (SPECT), to saline and 1.38 mg/kg procaine (Group I), and saline, 0.5 mg/kg and 1.0 mg/kg procaine (Group II). Compared to saline, 0.5 mg/kg procaine produced minimal rCBF changes, 1.0 mg/kg procaine induced both limbic and non-limbic activation, and 1.38 mg/kg procaine showed relatively specific rCBF limbic activation. Subjective responses increased in a dose-response manner. We conclude that a dose of 1.38 mg/kg procaine provides a more limited and specific activation of limbic structures than 1.00 mg/kg procaine and thus may be more useful as a specific probe of limbic function.
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Affiliation(s)
- Bryon Adinoff
- Department of Psychiatry, University of Texas Southwestern Medical Center, 4500 S. Lancaster Rd., TX 75216, Dallas, USA.
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31
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Anderson AK, Phelps EA. Is the human amygdala critical for the subjective experience of emotion? Evidence of intact dispositional affect in patients with amygdala lesions. J Cogn Neurosci 2002; 14:709-20. [PMID: 12167256 DOI: 10.1162/08989290260138618] [Citation(s) in RCA: 155] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
It is thought that the human amygdala is a critical component of the neural substrates of emotional experience, involved particularly in the generation of fear, anxiety, and general negative affectivity. Although many neuroimaging studies demonstrate findings consistent this notion, little evidence of altered emotional experience following amygdala damage has been gathered in humans. In a preliminary test of the amygdala's role in phenomenal affective states, we assessed the extent of experienced positive and negative affective states in patients with amygdala damage and age-, sex-, and education-matched controls. To assess chronic changes in experienced affect, all groups were administered the Positive and Negative Affect Schedules (PANAS, Watson, Clark, & Tellegen, 1988). In the first study, we examined the effects of amygdala lesions on affective traits in 10 left and 10 right amygdala-damaged patients, 1 patient with bilateral amygdala damage (SP), and 20 control subjects. Subjects were asked to indicate the typicality of different experiential states of positive (e.g., inspired, excited) and negative (e.g., afraid, nervous) valence. In a second study, we examined more closely the effects of bilateral amygdala damage on the day-to-day generation of affective states by administering the PANAS daily for a 30-day period to patient SP and age-, sex-, and education-matched controls. In both experiments, no differences in the magnitude and frequency of self-reported positive or negative affect were found between control subjects and patients with amygdala damage. Moreover, principal components analyses of the covariation among different affects (across individuals in Study 1 and within individuals across days in Study 2) confirmed a two-factor (positive vs. negative) description of experienced affect in controls. A highly similar two-factor description of experienced affect was found in patients with amygdala lesions. This suggests that the underlying structure of affective states was intact following amygdala damage. It is concluded that the human amygdala may be recruited during phenomenal affective states in the intact brain, but is not necessary for the production of these states.
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Abstract
Depression is a disorder of the representation and regulation of mood and emotion. The circuitry underlying the representation and regulation of normal emotion and mood is reviewed, including studies at the animal level, human lesion studies, and human brain imaging studies. This corpus of data is used to construct a model of the ways in which affect can become disordered in depression. Research on the prefrontal cortex, anterior cingulate, hippocampus, and amygdala is reviewed and abnormalities in the structure and function of these different regions in depression is considered. The review concludes with proposals for the specific types of processing abnormalities that result from dysfunctions in different parts of this circuitry and offers suggestions for the major themes upon which future research in this area should be focused.
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Affiliation(s)
- Richard J Davidson
- Laboratory for Affective Neuroscience and W.M. Keck Laboratory for Functional Brain Imaging and Behavior, University of Wisconsin-Madison, Madison, Wisconsin 53705-2280, USA.
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Shin LM, Whalen PJ, Pitman RK, Bush G, Macklin ML, Lasko NB, Orr SP, McInerney SC, Rauch SL. An fMRI study of anterior cingulate function in posttraumatic stress disorder. Biol Psychiatry 2001; 50:932-42. [PMID: 11750889 DOI: 10.1016/s0006-3223(01)01215-x] [Citation(s) in RCA: 402] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Several recent neuroimaging studies have provided data consistent with functional abnormalities in anterior cingulate cortex in posttraumatic stress disorder (PTSD). In our study, we implemented a cognitive activation paradigm to test the functional integrity of anterior cingulate cortex in PTSD. METHODS Eight Vietnam combat veterans with PTSD (PTSD Group) and eight Vietnam combat veterans without PTSD (non-PTSD Group) underwent functional magnetic resonance imaging (fMRI) while performing the Emotional Counting Stroop. In separate conditions, subjects counted the number of combat-related (Combat), generally negative (General Negative), and neutral (Neutral) words presented on a screen and pressed a button indicating their response. RESULTS In the Combat versus General Negative comparison, the non-PTSD group exhibited significant fMRI blood oxygenation level-dependent signal increases in rostral anterior cingulate cortex, but the PTSD group did not. CONCLUSIONS These findings suggest a diminished response in rostral anterior cingulate cortex in the presence of emotionally relevant stimuli in PTSD. We speculate that diminished recruitment of this region in PTSD may, in part, mediate symptoms such as distress and arousal upon exposure to reminders of trauma.
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Affiliation(s)
- L M Shin
- Department of Psychology, Tufts University, Medford, MA 02155, USA
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Brody AL, Saxena S, Mandelkern MA, Fairbanks LA, Ho ML, Baxter LR. Brain metabolic changes associated with symptom factor improvement in major depressive disorder. Biol Psychiatry 2001; 50:171-8. [PMID: 11513815 DOI: 10.1016/s0006-3223(01)01117-9] [Citation(s) in RCA: 154] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Symptoms of major depressive disorder (MDD) have been linked to regional brain function through imaging studies of symptom provocation in normal control subjects and baseline studies of subjects with MDD. We examined associations between change in depressive symptom factors and change in regional brain metabolism from before to after treatment of MDD. METHODS Thirty-nine outpatients with MDD underwent 18F-fluorodeoxyglucose positron emission tomography scanning before and after treatment with either paroxetine or interpersonal psychotherapy. Associations were determined between changes in regional brain metabolism and changes in four Hamilton Depression Rating Scale factors (anxiety/somatization [ANX], psychomotor retardation [PR], cognitive disturbance [COGN], and sleep disturbance) and two corresponding Profile of Mood States subscales (tension [TENS] and fatigue [FATIG]). RESULTS Improvement in ANX, PR, TENS, and FATIG factors was associated with decreasing ventral frontal lobe metabolism. Improvement in ANX and TENS was also associated with decreasing ventral anterior cingulate gyrus (AC) and anterior insula activity, whereas improvement in PR was associated with increasing dorsal AC activity. COGN improvement was associated with increasing dorsolateral prefrontal cortex metabolism. CONCLUSIONS Brain regions that show significant relationships with symptom provocation in normal control subjects have similar relationships with MDD symptoms as they improve with treatment.
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Affiliation(s)
- A L Brody
- Department of Psychiatry and Biobehavioral Sciences, UCLA School of Medicine, Los Angeles, California 90095, USA
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Abstract
Here we provide a review of the animal and human literature concerning the role of the amygdala in fear conditioning, considering its potential influence over autonomic and hormonal changes, motor behavior and attentional processes. A stimulus that predicts an aversive outcome will change neural transmission in the amygdala to produce the somatic, autonomic and endocrine signs of fear, as well as increased attention to that stimulus. It is now clear that the amygdala is also involved in learning about positively valenced stimuli as well as spatial and motor learning and this review strives to integrate this additional information. A review of available studies examining the human amygdala covers both lesion and electrical stimulation studies as well as the most recent functional neuroimaging studies. Where appropriate, we attempt to integrate basic information on normal amygdala function with our current understanding of psychiatric disorders, including pathological anxiety.
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Affiliation(s)
- M Davis
- Department of Psychiatry, Emory University School of Medicine, Atlanta, GA 30322, USA.
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Jiménez-Rivera CA, Segarra O, Jiménez Z, Waterhouse BD. Effects of intravenous cocaine administration on cerebellar Purkinje cell activity. Eur J Pharmacol 2000; 407:91-100. [PMID: 11050295 DOI: 10.1016/s0014-2999(00)00711-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The goal of the present study was to investigate the effects of intravenous cocaine administration on cerebellar Purkinje cell firing. Extracellular neuron activity was recorded and cells were locally excited with spaced microiontophoretic pulses of glutamate. Glutamate-evoked and spontaneous discharges were compared before and immediately following cocaine administration. Cocaine injections (1. 0 and 0.25 mg/kg, i.v.) induced a reversible suppression of both spontaneous activity and glutamate-evoked excitation. Procaine was ineffective in producing similar actions. Cocaine only inhibited glutamate-induced excitation in animals pre-treated with reserpine (5 mg/kg, i.p.). Propranolol injections (10 mg/kg, i.p.) were ineffective in blocking cocaine-induced inhibitions. Yohimbine (5 mg/kg, i.p.) pre-treatment abolished cocaine-induced suppressions of either spontaneous or glutamate-evoked excitation. Therefore, cocaine administration decreases Purkinje cell spontaneous and glutamate-evoked discharges by a mechanism involving alpha(2)-adrenoceptor activation. It is suggested that by changing the normal function of the cerebellum cocaine can produce drug-related alterations in overt behavior and cognition.
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Affiliation(s)
- C A Jiménez-Rivera
- Department of Physiology and Center for Molecular and Behavioral Neuroscience, Universidad Central del Caribe, Bayamón, Puerto Rico.
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Altshuler LL, Bartzokis G, Grieder T, Curran J, Jimenez T, Leight K, Wilkins J, Gerner R, Mintz J. An MRI study of temporal lobe structures in men with bipolar disorder or schizophrenia. Biol Psychiatry 2000; 48:147-62. [PMID: 10903411 DOI: 10.1016/s0006-3223(00)00836-2] [Citation(s) in RCA: 252] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Hippocampal atrophy has been described in postmortem and magnetic resonance imaging studies of schizophrenia. The specificity of this finding to schizophrenia remains to be determined. The neuropathology of bipolar disorder is understudied, and temporal lobe structures have only recently been evaluated. METHODS Twenty-four bipolar, 20 schizophrenic, and 18 normal comparison subjects were evaluated using magnetic resonance brain imaging. Image data were acquired using a three-dimensional spoiled GRASS sequence, and brain images were reformatted in three planes. Temporal lobe structures including the amygdala, hippocampus, parahippocampus, and total temporal lobe were measured to obtain volumes for each structure in the three subject groups. Severity of symptoms in both patient groups was assessed at the time the magnetic resonance images were obtained. RESULTS Hippocampal volumes were significantly smaller in the schizophrenic group than in both bipolar and normal comparison subjects. Further, amygdala volumes were significantly larger in the bipolar group than in both schizophrenic and normal comparison subjects. CONCLUSIONS The results suggest differences in affected limbic structures in patients with schizophrenia and bipolar disorder. These specific neuroanatomic abnormalities may shed light on the underlying pathophysiology and presentation of the two disorders.
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Affiliation(s)
- L L Altshuler
- Department of Psychiatry, UCLA Neuropsychiatric Institute, Los Angeles, California, USA
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Shin LM, Dougherty DD, Orr SP, Pitman RK, Lasko M, Macklin ML, Alpert NM, Fischman AJ, Rauch SL. Activation of anterior paralimbic structures during guilt-related script-driven imagery. Biol Psychiatry 2000; 48:43-50. [PMID: 10913506 DOI: 10.1016/s0006-3223(00)00251-1] [Citation(s) in RCA: 181] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Several recent neuroimaging studies have examined the neuroanatomical correlates of normal emotional states, such as happiness, sadness, fear, anger, anxiety, and disgust; however, no previous study has examined the emotional state of guilt. METHODS In the current study, we used positron emission tomography and the script-driven imagery paradigm to study regional cerebral blood flow (rCBF) during the transient emotional experience of guilt in eight healthy male participants. In the Guilt condition, participants recalled and imagined participating in a personal event involving the most guilt they had ever experienced. In the Neutral condition, participants recalled and imagined participating in an emotionally neutral personal event. RESULTS In the Guilt versus Neutral comparison, rCBF increases occurred in anterior paralimbic regions of the brain: bilateral anterior temporal poles, anterior cingulate gyrus, and left anterior insular cortex/inferior frontal gyrus. CONCLUSIONS These results, along with those of previous studies, are consistent with the notion that anterior paralimbic regions of the brain mediate negative emotional states in healthy individuals.
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Affiliation(s)
- L M Shin
- Department of Psychology, Tufts University, Medford, Massachusetts 02155, USA
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Kimbrell TA, George MS, Parekh PI, Ketter TA, Podell DM, Danielson AL, Repella JD, Benson BE, Willis MW, Herscovitch P, Post RM. Regional brain activity during transient self-induced anxiety and anger in healthy adults. Biol Psychiatry 1999; 46:454-65. [PMID: 10459394 DOI: 10.1016/s0006-3223(99)00103-1] [Citation(s) in RCA: 180] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND Several studies have demonstrated that transient self-induced sadness activates anterior paralimbic structures. To further examine the specificity of these findings and the neural substrates involved in anger and anxiety, we studied the neural correlates of the induction of anxiety and anger in healthy adults. METHODS We used H2(15)O and positron emission tomography (PET) to measure regional cerebral blood flow (rCBF) in 16 healthy adults during the induction of transient anxiety, anger, and neutral emotions. Subjects achieved differential emotions by recalling prior life events while viewing affect-appropriate faces. RESULTS Both the anxiety and anger conditions were associated with increased normalized rCBF in left inferior frontal and left temporal pole regions and decreased rCBF in right posterior temporal/parietal and right superior frontal cortex, compared to the neutral induction. Additionally, compared to neutral induction, anxiety was associated with increased rCBF in the left anterior cingulate and cuneus and decreased rCBF in right medial frontal cortex, while the anger induction was uniquely associated with increased rCBF in right temporal pole and thalamus. CONCLUSIONS Self-generated transient states of anxiety and anger are associated with both overlapping and distinct regional brain activity patterns and provide a template for further dissection of specific components of normal and pathologic emotions.
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Affiliation(s)
- T A Kimbrell
- Biological Psychiatry Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892-1272, USA
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