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Lim RY, Lew WCL, Ang KK. Review of EEG Affective Recognition with a Neuroscience Perspective. Brain Sci 2024; 14:364. [PMID: 38672015 PMCID: PMC11048077 DOI: 10.3390/brainsci14040364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2024] [Revised: 04/02/2024] [Accepted: 04/06/2024] [Indexed: 04/28/2024] Open
Abstract
Emotions are a series of subconscious, fleeting, and sometimes elusive manifestations of the human innate system. They play crucial roles in everyday life-influencing the way we evaluate ourselves, our surroundings, and how we interact with our world. To date, there has been an abundance of research on the domains of neuroscience and affective computing, with experimental evidence and neural network models, respectively, to elucidate the neural circuitry involved in and neural correlates for emotion recognition. Recent advances in affective computing neural network models often relate closely to evidence and perspectives gathered from neuroscience to explain the models. Specifically, there has been growing interest in the area of EEG-based emotion recognition to adopt models based on the neural underpinnings of the processing, generation, and subsequent collection of EEG data. In this respect, our review focuses on providing neuroscientific evidence and perspectives to discuss how emotions potentially come forth as the product of neural activities occurring at the level of subcortical structures within the brain's emotional circuitry and the association with current affective computing models in recognizing emotions. Furthermore, we discuss whether such biologically inspired modeling is the solution to advance the field in EEG-based emotion recognition and beyond.
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Affiliation(s)
- Rosary Yuting Lim
- Institute for Infocomm Research, Agency for Science, Technology and Research, A*STAR, 1 Fusionopolis Way, #21-01 Connexis, Singapore 138632, Singapore; (R.Y.L.); (W.-C.L.L.)
| | - Wai-Cheong Lincoln Lew
- Institute for Infocomm Research, Agency for Science, Technology and Research, A*STAR, 1 Fusionopolis Way, #21-01 Connexis, Singapore 138632, Singapore; (R.Y.L.); (W.-C.L.L.)
- School of Computer Science and Engineering, Nanyang Technological University, 50 Nanyang Ave., 32 Block N4 02a, Singapore 639798, Singapore
| | - Kai Keng Ang
- Institute for Infocomm Research, Agency for Science, Technology and Research, A*STAR, 1 Fusionopolis Way, #21-01 Connexis, Singapore 138632, Singapore; (R.Y.L.); (W.-C.L.L.)
- School of Computer Science and Engineering, Nanyang Technological University, 50 Nanyang Ave., 32 Block N4 02a, Singapore 639798, Singapore
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Aarts I, Thorsen AL, Vriend C, Planting C, van den Heuvel OA, Thomaes K. Effects of psychotherapy on brain activation during negative emotional processing in patients with posttraumatic stress disorder: a systematic review and meta-analysis. Brain Imaging Behav 2024; 18:444-455. [PMID: 38049598 DOI: 10.1007/s11682-023-00831-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/20/2023] [Indexed: 12/06/2023]
Abstract
Post-traumatic stress disorder (PTSD) is a debilitating condition which has been related to problems in emotional regulation, memory and cognitive control. Psychotherapy has a non-response rate of around 50% and understanding the neurobiological working mechanisms might help improve treatment. To integrate findings from multiple smaller studies, we performed the first meta-analysis of changes in brain activation with a specific focus on emotional processing after psychotherapy in PTSD patients. We performed a meta-analysis of brain activation changes after treatment during emotional processing for PTSD with seed-based d mapping using a pre-registered protocol (PROSPERO CRD42020211039). We analyzed twelve studies with 191 PTSD patients after screening 3700 studies. We performed systematic quality assessment both for the therapeutic interventions and neuroimaging methods. Analyses were done in the full sample and in a subset of studies that reported whole-brain results. We found decreased activation after psychotherapy in the left amygdala, (para)hippocampus, medial temporal lobe, inferior frontal gyrus, ventrolateral prefrontal cortex, right pallidum, anterior cingulate cortex, bilateral putamen, and insula. Decreased activation in the left amygdala and left ventrolateral PFC was also found in eight studies that reported whole-brain findings. Results did not survive correction for multiple comparisons. There is tentative support for decreased activation in the fear and cognitive control networks during emotional processing after psychotherapy for PTSD. Future studies would benefit from adopting a larger sample size, using designs that control for confounding variables, and investigating heterogeneity in symptom profiles and treatment response.
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Affiliation(s)
- Inga Aarts
- Sinai Centrum, Arkin, Amstelveen, The Netherlands.
- Department of Psychiatry, Amsterdam UMC location Vrije Universiteit Amsterdam, Boelelaan 1117, Amsterdam, The Netherlands.
- Department of Anatomy and Neurosciences, Amsterdam UMC location Vrije Universiteit Amsterdam, Boelelaan 1117, Amsterdam, The Netherlands.
| | - A L Thorsen
- Bergen Center for Brain Plasticity, Haukeland University Hospital, Bergen, Norway
- Center for Crisis Psychology, University of Bergen, Bergen, Norway
| | - C Vriend
- Department of Psychiatry, Amsterdam UMC location Vrije Universiteit Amsterdam, Boelelaan 1117, Amsterdam, The Netherlands
- Department of Anatomy and Neurosciences, Amsterdam UMC location Vrije Universiteit Amsterdam, Boelelaan 1117, Amsterdam, The Netherlands
- Amsterdam Neuroscience, Compulsivity, Impulsivity & Attention program, Amsterdam, The Netherlands
| | - C Planting
- GGZ inGeest Specialized Mental Health Care, Amsterdam, The Netherlands
- Vrije Universiteit Amsterdam, University Library, Amsterdam, The Netherlands
| | - O A van den Heuvel
- Department of Psychiatry, Amsterdam UMC location Vrije Universiteit Amsterdam, Boelelaan 1117, Amsterdam, The Netherlands
- Department of Anatomy and Neurosciences, Amsterdam UMC location Vrije Universiteit Amsterdam, Boelelaan 1117, Amsterdam, The Netherlands
- Bergen Center for Brain Plasticity, Haukeland University Hospital, Bergen, Norway
- Amsterdam Neuroscience, Compulsivity, Impulsivity & Attention program, Amsterdam, The Netherlands
| | - K Thomaes
- Sinai Centrum, Arkin, Amstelveen, The Netherlands
- Department of Psychiatry, Amsterdam UMC location Vrije Universiteit Amsterdam, Boelelaan 1117, Amsterdam, The Netherlands
- Department of Anatomy and Neurosciences, Amsterdam UMC location Vrije Universiteit Amsterdam, Boelelaan 1117, Amsterdam, The Netherlands
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Dirven BCJ, van Melis L, Daneva T, Dillen L, Homberg JR, Kozicz T, Henckens MJAG. Hippocampal Trauma Memory Processing Conveying Susceptibility to Traumatic Stress. Neuroscience 2024; 540:87-102. [PMID: 38220126 DOI: 10.1016/j.neuroscience.2024.01.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 12/04/2023] [Accepted: 01/10/2024] [Indexed: 01/16/2024]
Abstract
While the majority of the population is ever exposed to a traumatic event during their lifetime, only a fraction develops posttraumatic stress disorder (PTSD). Disrupted trauma memory processing has been proposed as a core factor underlying PTSD symptomatology. We used transgenic Targeted-Recombination-in-Active-Populations (TRAP) mice to investigate potential alterations in trauma-related hippocampal memory engrams associated with the development of PTSD-like symptomatology. Mice were exposed to a stress-enhanced fear learning paradigm, in which prior exposure to a stressor affects the learning of a subsequent fearful event (contextual fear conditioning using foot shocks), during which neuronal activity was labeled. One week later, mice were behaviorally phenotyped to identify mice resilient and susceptible to developing PTSD-like symptomatology. Three weeks post-learning, mice were re-exposed to the conditioning context to induce remote fear memory recall, and associated hippocampal neuronal activity was assessed. While no differences in the size of the hippocampal neuronal ensemble activated during fear learning were observed between groups, susceptible mice displayed a smaller ensemble activated upon remote fear memory recall in the ventral CA1, higher regional hippocampal parvalbuminneuronal density and a relatively lower activity of parvalbumininterneurons upon recall. Investigation of potential epigenetic regulators of the engram revealed rather generic (rather than engram-specific) differences between groups, with susceptible mice displaying lower hippocampal histone deacetylase 2 expression, and higher methylation and hydroxymethylation levels. These finding implicate variation in epigenetic regulation within the hippocampus, as well as reduced regional hippocampal activity during remote fear memory recall in interindividual differences in susceptibility to traumatic stress.
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Affiliation(s)
- Bart C J Dirven
- Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, 6500 HB Nijmegen, The Netherlands; Department of Medical Imaging, Anatomy, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, 6500 HB Nijmegen, The Netherlands
| | - Lennart van Melis
- Department of Medical Imaging, Anatomy, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, 6500 HB Nijmegen, The Netherlands
| | - Teya Daneva
- Department of Medical Imaging, Anatomy, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, 6500 HB Nijmegen, The Netherlands
| | - Lieke Dillen
- Department of Medical Imaging, Anatomy, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, 6500 HB Nijmegen, The Netherlands
| | - Judith R Homberg
- Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, 6500 HB Nijmegen, The Netherlands
| | - Tamas Kozicz
- Department of Medical Imaging, Anatomy, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, 6500 HB Nijmegen, The Netherlands; Center for Individualized Medicine, Department of Clinical Genomics, and Biochemical Genetics Laboratory, Mayo Clinic, Rochester, MN 55905, USA; University of Pecs Medical School, Department of Anatomy, Pecs, Hungary
| | - Marloes J A G Henckens
- Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, 6500 HB Nijmegen, The Netherlands.
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Zilcha-Mano S, Duek O, Suarez-Jimenez B, Zhu X, Lazarov A, Helpman L, Korem N, Malka M, Harpaz-Rotem I, Neria Y. Underlying Hippocampal Mechanism of Posttraumatic Stress Disorder Treatment Outcome: Evidence From Two Clinical Trials. BIOLOGICAL PSYCHIATRY GLOBAL OPEN SCIENCE 2023; 3:867-874. [PMID: 37881552 PMCID: PMC10593870 DOI: 10.1016/j.bpsgos.2023.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 12/12/2022] [Accepted: 01/23/2023] [Indexed: 02/05/2023] Open
Abstract
Background The hippocampus plays an important role in the pathophysiology of posttraumatic stress disorder (PTSD) and its prognosis. Accumulating findings suggest that individuals with larger pretreatment hippocampal volume are more likely to benefit from PTSD treatment, but the mechanism underlying this effect is unknown. We investigated whether further increase in hippocampal volume during treatment explains the better prognosis of individuals with greater pretreatment hippocampal volume. Methods We collected structural magnetic resonance imagesfrom patients with PTSD before and after treatment. We examined whether larger hippocampal volume moderates the effect of increased hippocampal volume during treatment on symptom reduction. Given the relatively small sample sizes of treatment studies with pre- and posttreatment magnetic resonance imaging, we focused on effect sizes and sought to replicate findings in an external sample. We tested our hypothesis in study 1 (N = 38; prolonged exposure therapy) and then tested whether the results could be externally replicated in study 2 (N = 20; ketamine infusion followed by exposure therapy). Results Findings from study 1 revealed that increased right hippocampal volume during treatment was associated with greater PTSD symptom reduction only in patients with greater pretreatment right hippocampal volume (p = .03; η2 = 0.13, a large effect). Findings were partially replicated in study 2 for depressive symptoms (p = .034; η2 = 0.25, a very large effect) and for PTSD symptoms (p = .15; η2 = 0.15, a large effect). Conclusions Elucidating increased hippocampal volume as one of the neural mechanisms predictive of therapeutic outcome for individuals with larger pretreatment hippocampal volume may help identify clinical targets for this subgroup.
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Affiliation(s)
| | - Or Duek
- Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
| | | | - Xi Zhu
- Department of Psychiatry, Columbia University Irving Medical Center and New York State Psychiatric Institute, New York, New York
| | - Amit Lazarov
- Department of Psychiatry, Columbia University Irving Medical Center and New York State Psychiatric Institute, New York, New York
- School of Psychological Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Liat Helpman
- Department of Counseling and Human Development, University of Haifa, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Nachshon Korem
- Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
- National Center for PTSD, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Michal Malka
- Department of Psychology, University of Haifa, Haifa, Israel
| | - Ilan Harpaz-Rotem
- Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
- National Center for PTSD, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Yuval Neria
- Department of Psychiatry, Columbia University Irving Medical Center and New York State Psychiatric Institute, New York, New York
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Feola B, Flook EA, Gardner H, Phan KL, Gwirtsman H, Olatunji B, Blackford JU. Altered bed nucleus of the stria terminalis and amygdala responses to threat in combat veterans with posttraumatic stress disorder. J Trauma Stress 2023; 36:359-372. [PMID: 36938747 PMCID: PMC10548436 DOI: 10.1002/jts.22918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 12/15/2022] [Accepted: 12/16/2022] [Indexed: 03/21/2023]
Abstract
Posttraumatic stress disorder (PTSD) significantly impacts many veterans. Although PTSD has been linked to alterations in the fear brain network, the disorder likely involves alterations in both the fear and anxiety networks. Fear involves responses to imminent, predictable threat and is driven by the amygdala, whereas anxiety involves responses to potential, unpredictable threat and engages the bed nucleus of the stria terminalis (BNST). The BNST has been implicated in PTSD, but the role of the BNST in combat veterans with PTSD has yet to be examined. Identifying alterations in BNST responses to unpredictable threat could provide important new targets for treatment. The current study examined whether veterans with PTSD have altered BNST or amygdala responses (function and connectivity) to unpredictable and predictable threat. The fMRI task involved viewing predictable threat cues followed by threat images, predictable neutral cues followed by neutral images, and unpredictable threat cues followed by either a threat or neutral image. Participants included 32 combat-exposed veterans with PTSD and 13 combat-exposed controls without PTSD. Across all conditions, veterans with PTSD had heightened BNST activation and displayed stronger BNST and amygdala connectivity with multiple fear and anxiety regions (hypothalamus, hippocampus, insula, ventromedial prefrontal cortex) relative to controls. In contrast, combat controls showed a pattern of stronger connectivity during neutral conditions (e.g., BNST-vmPFC), which may suggest a neural signature of resilience to developing PTSD, ηp 2 = .087-.527, ps < .001. These findings have implications for understanding fear and anxiety networks that may contribute to the development and maintenance of PTSD.
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Affiliation(s)
- Brandee Feola
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Elizabeth A Flook
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Department of Psychiatry, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Hannah Gardner
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - K Luan Phan
- Department of Psychiatry, The Ohio State University, Columbus, Ohio, USA
| | - Harry Gwirtsman
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Tennessee Valley HealthCare System, U.S. Department of Veterans Affairs, Nashville, Tennessee, USA
| | - Bunmi Olatunji
- Department of Psychology, Vanderbilt University, Nashville, Tennessee, USA
| | - Jennifer Urbano Blackford
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Tennessee Valley HealthCare System, U.S. Department of Veterans Affairs, Nashville, Tennessee, USA
- Munroe-Meyer Institute, University of Nebraska Medical Center, Omaha, Nebraska, USA
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Nicholson EL, Garry MI, Ney LJ, Hsu CMK, Zuj DV, Felmingham KL. The influence of the BDNF Val66Met genotype on emotional recognition memory in post-traumatic stress disorder. Sci Rep 2023; 13:5033. [PMID: 36977737 PMCID: PMC10050310 DOI: 10.1038/s41598-023-30787-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 03/01/2023] [Indexed: 03/30/2023] Open
Abstract
Dysregulated consolidation of emotional memories is a core feature of posttraumatic stress disorder (PTSD). Brain Derived Neurotrophic Factor (BDNF) influences synaptic plasticity and emotional memory consolidation. The BDNF Val66Met polymorphism has been associated with PTSD risk and memory deficits respectively, although findings have been inconsistent, potentially due to a failure to control for important confounds such as sex, ethnicity, and the timing/extent of previous trauma experiences. Furthermore, very little research has examined the impact of BDNF genotypes on emotional memory in PTSD populations. This study investigated the interaction effects of Val66Met and PTSD symptomatology in an emotional recognition memory task in 234 participants divided into healthy control (n = 85), trauma exposed (TE: n = 105) and PTSD (n = 44) groups. Key findings revealed impaired negative recognition memory in PTSD compared to control and TE groups and in participants with the Val/Met compared to the Val/Val genotype. There was a group × genotype interaction showing no Met effect in the TE group despite significant effects in PTSD and controls. Results suggest that people previously exposed to trauma who do not develop PTSD may be protected from the BDNF Met effect, however more research is needed to replicate findings and to explore the epigenetic and neural processes involved.
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Affiliation(s)
- Emma Louise Nicholson
- Melbourne School of Psychological Sciences, University of Melbourne, Redmond Barry Building, Parkville, VIC, 3010, Australia.
| | - Michael I Garry
- School of Psychological Sciences, University of Tasmania, Hobart, Australia
| | - Luke J Ney
- School of Psychological Sciences, University of Tasmania, Hobart, Australia
- Faculty of Health, School of Psychology and Counselling, Queensland University of Technology, Brisbane, Australia
| | - Chia-Ming K Hsu
- School of Psychological Sciences, University of Tasmania, Hobart, Australia
| | - Daniel V Zuj
- School of Psychological Sciences, University of Tasmania, Hobart, Australia
- Experimental Psychopathology Lab, Department of Psychology, Swansea University, Swansea, UK
| | - Kim L Felmingham
- Melbourne School of Psychological Sciences, University of Melbourne, Redmond Barry Building, Parkville, VIC, 3010, Australia
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Choi JJ, Martins JS, Hwang S, Sinha R, Seo D. Neural correlates linking trauma and physical symptoms. Psychiatry Res Neuroimaging 2022; 327:111560. [PMID: 36327865 PMCID: PMC9757618 DOI: 10.1016/j.pscychresns.2022.111560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 10/13/2022] [Accepted: 10/23/2022] [Indexed: 11/06/2022]
Abstract
Trauma and chronic pain frequently co-occur, but the underlying neurological mechanisms are poorly understood. The current study investigated the neural correlates of stress and physical symptoms in trauma patients using functional magnetic resonance imaging (fMRI) and follow-up smartphone surveys. Participants were 10 patients diagnosed with Trauma- and Stressor-Related Disorders and 18 demographically-matched healthy controls who completed a fMRI stress provocation task in which they viewed stressful and neutral-relaxing images. Subsequently, participants completed daily smartphone surveys which prospectively monitored their stress and physical symptoms for 30 days. The trauma group experienced a significantly higher frequency of physical symptoms than controls during the follow-up period. During stress, trauma patients exhibited increased activity in the hippocampus, insula, and sensorimotor areas, but decreased activity in the ventromedial prefrontal cortex (vmPFC), lateral prefrontal cortex (LPFC), and dorsal striatum relative to controls. In all participants, higher physical symptom frequency was significantly associated with a hyperactive left hippocampal response to stress. The current study reports that trauma is characterized by greater physical symptoms and decreased prefrontal but increased limbic responses to stress. Our findings suggest that trauma may increase physical health symptoms by compromising hippocampal function, which could also increase vulnerability to stress- and pain-related disorders.
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Affiliation(s)
- Justin J Choi
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States of America.
| | - Jorge S Martins
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States of America; William James Center for Research, ISPA-Instituto Universitário, Lisbon, Portugal
| | - Seungju Hwang
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States of America
| | - Rajita Sinha
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States of America; Department of Neuroscience, Yale University School of Medicine, New Haven, CT, United States of America
| | - Dongju Seo
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States of America.
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Insomnia and Post-traumatic Stress Disorder: A Meta-analysis on Interrelated Association (n=57,618) and Prevalence (n=573,665). Neurosci Biobehav Rev 2022; 141:104850. [DOI: 10.1016/j.neubiorev.2022.104850] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 08/27/2022] [Accepted: 08/27/2022] [Indexed: 12/14/2022]
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Mattera A, Cavallo A, Granato G, Baldassarre G, Pagani M. A Biologically Inspired Neural Network Model to Gain Insight Into the Mechanisms of Post-Traumatic Stress Disorder and Eye Movement Desensitization and Reprocessing Therapy. Front Psychol 2022; 13:944838. [PMID: 35911047 PMCID: PMC9326218 DOI: 10.3389/fpsyg.2022.944838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 06/06/2022] [Indexed: 01/09/2023] Open
Abstract
Eye movement desensitization and reprocessing (EMDR) therapy is a well-established therapeutic method to treat post-traumatic stress disorder (PTSD). However, how EMDR exerts its therapeutic action has been studied in many types of research but still needs to be completely understood. This is in part due to limited knowledge of the neurobiological mechanisms underlying EMDR, and in part to our incomplete understanding of PTSD. In order to model PTSD, we used a biologically inspired computational model based on firing rate units, encompassing the cortex, hippocampus, and amygdala. Through the modulation of its parameters, we fitted real data from patients treated with EMDR or classical exposure therapy. This allowed us to gain insights into PTSD mechanisms and to investigate how EMDR achieves trauma remission.
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Angiotensin antagonist inhibits preferential negative memory encoding via decreasing hippocampus activation and its coupling with amygdala. BIOLOGICAL PSYCHIATRY: COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2022; 7:970-978. [DOI: 10.1016/j.bpsc.2022.05.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 05/11/2022] [Accepted: 05/13/2022] [Indexed: 11/21/2022]
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Henner RL, Keshavan MS, Hill KP. Review of potential psychedelic treatments for PTSD. J Neurol Sci 2022; 439:120302. [DOI: 10.1016/j.jns.2022.120302] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 04/27/2022] [Accepted: 05/24/2022] [Indexed: 12/20/2022]
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12
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Song C, Yeh PH, Ollinger J, Sours Rhodes C, Lippa SM, Riedy G, Bonavia GH. Altered Metabolic Interrelationships in the Cortico-Limbic Circuitry in Military Service Members with Persistent Post-Traumatic Stress Disorder Symptoms Following Mild Traumatic Brain Injury. Brain Connect 2021; 12:602-616. [PMID: 34428937 DOI: 10.1089/brain.2021.0036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Introduction: Comorbid mild traumatic brain injury (mTBI) and post-traumatic stress disorder (PTSD) are common in military service members. The aim of this study is to investigate brain metabolic interrelationships in service members with and without persistent PTSD symptoms after mTBI by using 18F-fluorodeoxyglucose (FDG) positron emission tomography. Methods: Service members (n = 408) diagnosed with mTBI were studied retrospectively. Principal component analysis was applied to identify latent metabolic systems, and the associations between metabolic latent systems and self-report measures of post-concussive and PTSD symptoms were evaluated. Participants were divided into two groups based on DSM-IV-TR (Diagnostic and Statistical Manual of Mental Disorders, fourth edition-Text Revision) criteria for PTSD, and structural equation modeling was performed to test a priori hypotheses on metabolic interrelationships among the brain regions in the cortico-limbic circuitry responsible for top-down control and bottom-up emotional processing. The differences in metabolic interrelationships between age-matched PTSD-absent (n = 204) and PTSD-present (n = 204) groups were evaluated. Results: FDG uptake in the temporo-limbic system was positively correlated with post-concussive and hyperarousal symptoms. For the bottom-up emotional processing, the insula and amygdala-hippocampal complex in the PTSD-present group had stronger metabolic interrelationships with the bilateral rostral anterior cingulate, left lingual, right lateral occipital, and left superior temporal cortices, but a weaker relationship with the right precuneus cortex, compared with the PTSD-absent group. For the top-down control, the PTSD-present group had decreased metabolic engagements of the dorsolateral prefrontal cortex on the amygdala. Discussion: Our results suggest altered metabolic interrelationships in the cortico-limbic circuitry in mTBI subjects with persistent PTSD symptoms, which may underlie the pathophysiological mechanisms of comorbid mTBI and PTSD. Impact statement This is the first 18F-fluorodeoxyglucose positron emission tomography study to investigate brain metabolic interrelationships in service members with persistent post-traumatic stress disorder (PTSD) symptoms after mild traumatic brain injury (mTBI). We identified that the temporo-limbic metabolic system was associated with post-concussive and hyperarousal symptoms. Further, brain metabolic interrelationships in the cortico-limbic circuitry were altered in mTBI subjects with significant PTSD symptoms compared with those without them.
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Affiliation(s)
- Chihwa Song
- National Intrepid Center of Excellence, Walter Reed National Military Medical Center, Bethesda, Maryland, USA
| | - Ping-Hong Yeh
- National Intrepid Center of Excellence, Walter Reed National Military Medical Center, Bethesda, Maryland, USA
| | - John Ollinger
- National Intrepid Center of Excellence, Walter Reed National Military Medical Center, Bethesda, Maryland, USA
| | - Chandler Sours Rhodes
- National Intrepid Center of Excellence, Walter Reed National Military Medical Center, Bethesda, Maryland, USA
| | - Sara M Lippa
- National Intrepid Center of Excellence, Walter Reed National Military Medical Center, Bethesda, Maryland, USA
| | - Gerard Riedy
- National Intrepid Center of Excellence, Walter Reed National Military Medical Center, Bethesda, Maryland, USA
| | - Grant H Bonavia
- National Intrepid Center of Excellence, Walter Reed National Military Medical Center, Bethesda, Maryland, USA
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13
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Castelhano J, Lima G, Teixeira M, Soares C, Pais M, Castelo-Branco M. The Effects of Tryptamine Psychedelics in the Brain: A meta-Analysis of Functional and Review of Molecular Imaging Studies. Front Pharmacol 2021; 12:739053. [PMID: 34658876 PMCID: PMC8511767 DOI: 10.3389/fphar.2021.739053] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 09/06/2021] [Indexed: 11/13/2022] Open
Abstract
There is an increasing interest in the neural effects of psychoactive drugs, in particular tryptamine psychedelics, which has been incremented by the proposal that they have potential therapeutic benefits, based on their molecular mimicry of serotonin. It is widely believed that they act mainly through 5HT2A receptors but their effects on neural activation of distinct brain systems are not fully understood. We performed a quantitative meta-analysis of brain imaging studies to investigate the effects of substances within this class (e.g., LSD, Psilocybin, DMT, Ayahuasca) in the brain from a molecular and functional point of view. We investigated the question whether the changes in activation patterns and connectivity map into regions with larger 5HT1A/5HT2A receptor binding, as expected from indolaemine hallucinogens (in spite of the often reported emphasis only on 5HT2AR). We did indeed find that regions with changed connectivity and/or activation patterns match regions with high density of 5HT2A receptors, namely visual BA19, visual fusiform regions in BA37, dorsal anterior and posterior cingulate cortex, medial prefrontal cortex, and regions involved in theory of mind such as the surpramarginal gyrus, and temporal cortex (rich in 5HT1A receptors). However, we also found relevant patterns in other brain regions such as dorsolateral prefrontal cortex. Moreover, many of the above-mentioned regions also have a significant density of both 5HT1A/5HT2A receptors, and available PET studies on the effects of psychedelics on receptor occupancy are still quite scarce, precluding a metanalytic approach. Finally, we found a robust neuromodulatory effect in the right amygdala. In sum, the available evidence points towards strong neuromodulatory effects of tryptamine psychedelics in key brain regions involved in mental imagery, theory of mind and affective regulation, pointing to potential therapeutic applications of this class of substances.
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Feng C, Gu R, Li T, Wang L, Zhang Z, Luo W, Eickhoff SB. Separate neural networks of implicit emotional processing between pictures and words: A coordinate-based meta-analysis of brain imaging studies. Neurosci Biobehav Rev 2021; 131:331-344. [PMID: 34562542 DOI: 10.1016/j.neubiorev.2021.09.041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 09/14/2021] [Accepted: 09/21/2021] [Indexed: 02/02/2023]
Abstract
Both pictures and words are frequently employed as experimental stimuli to investigate the neurocognitive mechanisms of emotional processing. However, it remains unclear whether emotional picture processing and emotional word processing share neural underpinnings. To address this issue, we focus on neuroimaging studies examining the implicit processing of affective words and pictures, which require participants to meet cognitive task demands under the implicit influence of emotional pictorial or verbal stimuli. A coordinate-based activation likelihood estimation meta-analysis was conducted on these studies, which revealed no common activation maximum between the picture and word conditions. Specifically, implicit negative picture processing (35 experiments, 393 foci, and 932 subjects) engages the bilateral amygdala, left hippocampus, fusiform gyri, and right insula, which are mainly located in the subcortical network and visual network associated with bottom-up emotional responses. In contrast, implicit negative word processing (34 experiments, 316 foci, and 799 subjects) engages the default mode network and fronto-parietal network including the ventrolateral prefrontal cortex, dorsolateral prefrontal cortex, and dorsomedial prefrontal cortex, indicating the involvement of top-down semantic processing and emotion regulation. Our findings indicate that affective pictures (that intrinsically have an affective valence) and affective words (that inherit the affective valence from their object) modulate implicit emotional processing in different ways, and therefore recruit distinct brain systems.
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Affiliation(s)
- Chunliang Feng
- Key Laboratory of Brain, Cognition and Education Sciences (South China Normal University), Ministry of Education, Guangzhou, China; Guangdong Provincial Key Laboratory of Mental Health and Cognitive Science, Center for Studies of Psychological Application, School of Psychology, South China Normal University, Guangzhou, China.
| | - Ruolei Gu
- CAS Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing, China.
| | - Ting Li
- Institute of Brain Research and Rehabilitation (IBRR), South China Normal University, Guangzhou, China
| | - Li Wang
- Collaborative Innovation Center of Assessment for Basic Education Quality, Beijing Normal University, Beijing, China
| | - Zhixing Zhang
- Key Laboratory of Brain, Cognition and Education Sciences (South China Normal University), Ministry of Education, Guangzhou, China; Guangdong Provincial Key Laboratory of Mental Health and Cognitive Science, Center for Studies of Psychological Application, School of Psychology, South China Normal University, Guangzhou, China
| | - Wenbo Luo
- Research Center of Brain and Cognitive Neuroscience, Liaoning Normal University, Dalian, China
| | - Simon B Eickhoff
- Institute of Systems Neuroscience, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany; Institute of Neuroscience and Medicine, Brain & Behaviour (INM-7), Research Centre Jülich, Jülich, Germany
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15
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Neural correlates of emotional reactivity and regulation in traumatized North Korean refugees. Transl Psychiatry 2021; 11:452. [PMID: 34480013 PMCID: PMC8417257 DOI: 10.1038/s41398-021-01579-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 08/05/2021] [Accepted: 08/19/2021] [Indexed: 11/24/2022] Open
Abstract
Refugees often report heightened emotional reactivity and emotion regulation difficulties and are at high risk for mental health problems. Given that refugees are repeatedly exposed to traumatic events that may cause changes in the brain, the present study examined neural correlates of emotional reactivity and regulation and their associations with refugee features (e.g., cumulative trauma) and the severity of psychiatric symptoms (e.g., post-traumatic stress disorder [PTSD]) in North Korean (NK) refugees. Forty NK refugees with trauma exposure and varying levels of psychopathology and 41 healthy South Korean (SK) controls without trauma exposure participated in this study. They performed an emotion regulation task during a functional magnetic resonance imaging (fMRI) assessment. Region of interest (ROI), whole brain, and generalized psychophysiological interaction (gPPI) analyses were conducted. NK refugees with trauma exposure and varying levels of psychopathology showed increased activation in response to negative socio-affective pictures in regions involved in affective processing, including the amygdala and hippocampus, relative to healthy SK controls without trauma exposure. They also exhibited greater prefrontal cortex (PFC) activation, amygdala-PFC functional connectivity (FC), and hippocampal-PFC FC during emotion regulation. More severe PTSD symptoms were associated with greater hippocampal response to negative pictures (vs. neutral pictures) in NK refugees. This study provides neuroscientific evidence for neural alterations in association with emotional reactivity and regulation in traumatized refugees. These findings may contribute to a better mechanistic understanding of emotional reactivity and regulation in refugees and suggest potential ways to address the emotional and mental problems of traumatized refugees.
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Dudek E, Dodell-Feder D. The efficacy of real-time functional magnetic resonance imaging neurofeedback for psychiatric illness: A meta-analysis of brain and behavioral outcomes. Neurosci Biobehav Rev 2021; 121:291-306. [PMID: 33370575 PMCID: PMC7856210 DOI: 10.1016/j.neubiorev.2020.12.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 12/01/2020] [Accepted: 12/18/2020] [Indexed: 12/13/2022]
Abstract
Real-time functional magnetic resonance imaging neurofeedback (rtfMRI-NF) has gained popularity as an experimental treatment for a variety of psychiatric illnesses. However, there has yet to be a quantitative review regarding its efficacy. Here, we present the first meta-analysis of rtfMRI-NF for psychiatric disorders, evaluating its impact on brain and behavioral outcomes. Our literature review identified 17 studies and 105 effect sizes across brain and behavioral outcomes. We find that rtfMRI-NF produces a medium-sized effect on neural activity during training (g = .59, 95 % CI [.44, .75], p < .0001), a large-sized effect after training when no neurofeedback is provided (g = .84, 95 % CI [.37, 1.31], p = .005), and small-sized effects for behavioral outcomes (symptoms g = .37, 95 % CI [.16, .58], p = .002; cognition g = .23, 95 % CI [-.33, .78], p = .288). Mixed-effects analyses revealed few moderators. Together, these data suggest a positive impact of rtfMRI-NF on brain and behavioral outcomes, although more research is needed to determine how rtfMRI-NF works, for whom, and under what circumstances.
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Affiliation(s)
- Emily Dudek
- Department of Psychology, University of Rochester, United States
| | - David Dodell-Feder
- Department of Psychology, University of Rochester, United States; Department of Neuroscience, University of Rochester Medical Center, United States.
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Bremner JD, Gurel NZ, Wittbrodt MT, Shandhi MH, Rapaport MH, Nye JA, Pearce BD, Vaccarino V, Shah AJ, Park J, Bikson M, Inan OT. Application of Noninvasive Vagal Nerve Stimulation to Stress-Related Psychiatric Disorders. J Pers Med 2020; 10:E119. [PMID: 32916852 PMCID: PMC7563188 DOI: 10.3390/jpm10030119] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 09/02/2020] [Accepted: 09/03/2020] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Vagal Nerve Stimulation (VNS) has been shown to be efficacious for the treatment of depression, but to date, VNS devices have required surgical implantation, which has limited widespread implementation. METHODS New noninvasive VNS (nVNS) devices have been developed which allow external stimulation of the vagus nerve, and their effects on physiology in patients with stress-related psychiatric disorders can be measured with brain imaging, blood biomarkers, and wearable sensing devices. Advantages in terms of cost and convenience may lead to more widespread implementation in psychiatry, as well as facilitate research of the physiology of the vagus nerve in humans. nVNS has effects on autonomic tone, cardiovascular function, inflammatory responses, and central brain areas involved in modulation of emotion, all of which make it particularly applicable to patients with stress-related psychiatric disorders, including posttraumatic stress disorder (PTSD) and depression, since dysregulation of these circuits and systems underlies the symptomatology of these disorders. RESULTS This paper reviewed the physiology of the vagus nerve and its relevance to modulating the stress response in the context of application of nVNS to stress-related psychiatric disorders. CONCLUSIONS nVNS has a favorable effect on stress physiology that is measurable using brain imaging, blood biomarkers of inflammation, and wearable sensing devices, and shows promise in the prevention and treatment of stress-related psychiatric disorders.
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Affiliation(s)
- James Douglas Bremner
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA 30322, USA; (M.T.W.); (M.H.R.)
- Department of Radiology, Emory University School of Medicine, Atlanta, GA 30322, USA;
- Atlanta VA Medical Center, Decatur, GA 30033, USA; (A.J.S.); (J.P.)
| | - Nil Z. Gurel
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA; (N.Z.G.); (M.H.S.); (O.T.I.)
| | - Matthew T. Wittbrodt
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA 30322, USA; (M.T.W.); (M.H.R.)
| | - Mobashir H. Shandhi
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA; (N.Z.G.); (M.H.S.); (O.T.I.)
| | - Mark H. Rapaport
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA 30322, USA; (M.T.W.); (M.H.R.)
| | - Jonathon A. Nye
- Department of Radiology, Emory University School of Medicine, Atlanta, GA 30322, USA;
| | - Bradley D. Pearce
- Department of Epidemiology, Rollins School of Public Health, Atlanta, GA 30322, USA; (B.D.P.); (V.V.)
| | - Viola Vaccarino
- Department of Epidemiology, Rollins School of Public Health, Atlanta, GA 30322, USA; (B.D.P.); (V.V.)
- Department of Medicine, Cardiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Amit J. Shah
- Atlanta VA Medical Center, Decatur, GA 30033, USA; (A.J.S.); (J.P.)
- Department of Epidemiology, Rollins School of Public Health, Atlanta, GA 30322, USA; (B.D.P.); (V.V.)
- Department of Medicine, Cardiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Jeanie Park
- Atlanta VA Medical Center, Decatur, GA 30033, USA; (A.J.S.); (J.P.)
- Department of Medicine, Renal Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Marom Bikson
- Department of Biomedical Engineering, City University of New York, New York, NY 10010, USA;
| | - Omer T. Inan
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA; (N.Z.G.); (M.H.S.); (O.T.I.)
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
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Fitzgerald JM, Belleau EL, Miskovich TA, Pedersen WS, Larson CL. Multi-voxel pattern analysis of amygdala functional connectivity at rest predicts variability in posttraumatic stress severity. Brain Behav 2020; 10:e01707. [PMID: 32525273 PMCID: PMC7428479 DOI: 10.1002/brb3.1707] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 04/16/2020] [Accepted: 05/15/2020] [Indexed: 12/22/2022] Open
Abstract
INTRODUCTION Resting state functional magnetic resonance imaging (rsfMRI) studies demonstrate that individuals with posttraumatic stress disorder (PTSD) exhibit atypical functional connectivity (FC) between the amygdala, involved in the generation of emotion, and regions responsible for emotional appraisal (e.g., insula, orbitofrontal cortex [OFC]) and regulation (prefrontal cortex [PFC], anterior cingulate cortex). Consequently, atypical amygdala FC within an emotional processing and regulation network may be a defining feature of PTSD, although altered FC does not seem constrained to one brain region. Instead, altered amygdala FC involves a large, distributed brain network in those with PTSD. The present study used a machine-learning data-driven approach, multi-voxel pattern analysis (MVPA), to predict PTSD severity based on whole-brain patterns of amygdala FC. METHODS Trauma-exposed adults (N = 90) completed the PTSD Checklist-Civilian Version to assess symptoms and a 5-min rsfMRI. Whole-brain FC values to bilateral amygdala were extracted and used in a relevance vector regression analysis with a leave-one-out approach for cross-validation with permutation testing (1,000) to obtain significance values. RESULTS Results demonstrated that amygdala FC predicted PCL-C scores with statistically significant accuracy (r = .46, p = .001; mean sum of squares = 130.46, p = .001; R2 = 0.21, p = .001). Prediction was based on whole-brain amygdala FC, although regions that informed prediction (top 10%) included the OFC, amygdala, and dorsolateral PFC. CONCLUSION Findings demonstrate the utility of MVPA based on amygdala FC to predict individual severity of PTSD symptoms and that amygdala FC within a fear acquisition and regulation network contributed to accurate prediction.
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Affiliation(s)
| | - Emily L Belleau
- Department of Psychiatry, McLean Hospital, Belmont, MA, USA.,Harvard Medical School, Boston, MA, USA
| | | | - Walker S Pedersen
- Center for Healthy Minds, University of Wisconsin-Madison, Madison, WI, USA
| | - Christine L Larson
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
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Kim ES, Kim HE, Kim JJ. The neural influence of autobiographical memory related to the parent-child relationship on psychological health in adulthood. PLoS One 2020; 15:e0231592. [PMID: 32282812 PMCID: PMC7153857 DOI: 10.1371/journal.pone.0231592] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 03/26/2020] [Indexed: 12/31/2022] Open
Abstract
The recollection of childhood memories is affected by the subjects involved, such as father and mother, and by the context. This study aimed to clarify the neural influence of autobiographical memory related to the parent-child relationship on psychological health in adulthood. Twenty-nine healthy volunteers participated in a functional magnetic resonance imaging experiment using a childhood memory recollection task, in which they appraised the emotion a parent would have provided in a given situation. Whole-brain univariate and psychophysiological interaction analyses were performed. Neuroimaging results indicated notable involvement of the caudal anterior cingulate cortex and precuneus in autobiographical memory related to the parent-child relationship, and their activities were closely associated with the level of depression and self-esteem, respectively. The functional connectivity results indicated increased connectivity between the caudal anterior cingulate cortex and fusiform gyrus for the father-positive condition compared to the mother-positive condition and there was a positive correlation between the strength of connectivity between the two regions and the anxiety level. Our findings suggest the processing of negative affect and the personalness of autobiographical memories are distinctly engaged depending on the parent in question and the situational valence. The present study illuminates the impact of autobiographical memory processes on various dimensions of psychological health.
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Affiliation(s)
- Eun Seong Kim
- Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Department of Occupational Therapy, Chunnam Techno University, Gokseong, Republic of Korea
| | - Hesun Erin Kim
- Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jae-Jin Kim
- Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea
- Department of Psychiatry, Yonsei University Gangnam Severance Hospital, Seoul, Republic of Korea
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20
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Amygdala functional connectivity in the acute aftermath of trauma prospectively predicts severity of posttraumatic stress symptoms. Neurobiol Stress 2020; 12:100217. [PMID: 32435666 PMCID: PMC7231977 DOI: 10.1016/j.ynstr.2020.100217] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 02/20/2020] [Accepted: 03/27/2020] [Indexed: 12/20/2022] Open
Abstract
Understanding neural mechanisms that confer risk for posttraumatic stress disorder (PTSD) is critical for earlier intervention, yet longitudinal work has been sparse. The amygdala is part of a core network consistently implicated in PTSD symptomology. Most neural models of PTSD have focused on the amygdala's interactions with the dorsal anterior cingulate cortex, ventromedial prefrontal cortex, and hippocampus. However, an increasing number of studies have linked PTSD symptoms to aberrations in amygdala functional connections with other brain regions involved in emotional information processing, self-referential processing, somatosensory processing, visual processing, and motor control. In the current study, trauma-exposed individuals (N = 54) recruited from the emergency department completed a resting state fMRI scan as well as a script-driven trauma recall fMRI task scan two-weeks post-trauma along with demographic, PTSD, and other clinical symptom questionnaires two-weeks and six-months post-trauma. We examined whether amygdala-whole brain functional connectivity (FC) during rest and task could predict six-month post-trauma PTSD symptoms. More negative amygdala-cerebellum and amygdala-postcentral gyrus FC during rest as well as more negative amygdala-postcentral gyrus and amygdala-midcingulate cortex during recall of the trauma memory predicted six-month post-trauma PTSD after controlling for scanner type. Follow-up multiple regression sensitivity analyses controlling for several other relevant predictors of PTSD symptoms, revealed that amygdala-cerebellum FC during rest and amygdala-postcentral gyrus FC during trauma recall were particularly robust predictors of six-month PTSD symptoms. The results extend cross-sectional studies implicating abnormal FC of the amygdala with other brain regions involved in somatosensory processing, motor control, and emotional information processing in PTSD, to the prospective prediction of risk for chronic PTSD. This work may contribute to earlier identification of at-risk individuals and elucidate potential intervention targets.
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21
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Suarez-Jimenez B, Zhu X, Lazarov A, Mann JJ, Schneier F, Gerber A, Barber JP, Chambless DL, Neria Y, Milrod B, Markowitz JC. Anterior hippocampal volume predicts affect-focused psychotherapy outcome. Psychol Med 2020; 50:396-402. [PMID: 30773148 PMCID: PMC6698431 DOI: 10.1017/s0033291719000187] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
BACKGROUND The hippocampus plays an important role in psychopathology and treatment outcome. While posterior hippocampus (PH) may be crucial for the learning process that exposure-based treatments require, affect-focused treatments might preferentially engage anterior hippocampus (AH). Previous studies have distinguished the different functions of these hippocampal sub-regions in memory, learning, and emotional processes, but not in treatment outcome. Examining two independent clinical trials, we hypothesized that anterior hippocampal volume would predict outcome of affect-focused treatment outcome [Interpersonal Psychotherapy (IPT); Panic-Focused Psychodynamic Psychotherapy (PFPP)], whereas posterior hippocampal volume would predict exposure-based treatment outcome [Prolonged Exposure (PE); Cognitive Behavioral Therapy (CBT); Applied Relaxation Training (ART)]. METHODS Thirty-five patients with posttraumatic stress disorder (PTSD) and 24 with panic disorder (PD) underwent structural magnetic resonance imaging (MRI) before randomization to affect-focused (IPT for PTSD; PFPP for PD) or exposure-based treatments (PE for PTSD; CBT or ART for PD). AH and PH volume were regressed with clinical outcome changes. RESULTS Baseline whole hippocampal volume did not predict post-treatment clinical severity scores in any treatment. For affect-focused treatments, but not exposure-based treatments, anterior hippocampal volume predicted clinical improvement. Smaller AH correlated with greater affect-focused treatment improvement. Posterior hippocampal volume did not predict treatment outcome. CONCLUSIONS This is the first study to explore associations between hippocampal volume sub-regions and treatment outcome in PTSD and PD. Convergent results suggest that affect-focused treatment may influence the clinical outcome through the 'limbic' AH, whereas exposure-based treatments do not. These preliminary, theory-congruent, therapeutic findings require replication in a larger clinical trial.
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Affiliation(s)
| | - Xi Zhu
- Columbia University College of Physicians & Surgeons, New York, NY, USA
| | - Amit Lazarov
- Columbia University College of Physicians & Surgeons, New York, NY, USA
- School of Psychological Sciences, Tel-Aviv University, Tel Aviv, Israel
| | - J. John Mann
- Columbia University College of Physicians & Surgeons, New York, NY, USA
- New York State Psychiatric Institute, New York, NY, USA
| | - Franklin Schneier
- Columbia University College of Physicians & Surgeons, New York, NY, USA
- New York State Psychiatric Institute, New York, NY, USA
| | - Andrew Gerber
- Columbia University College of Physicians & Surgeons, New York, NY, USA
- Silver Hill Hospital, New Canaan, CT, USA
| | - Jacques P. Barber
- Adelphi University, Garden City, NY, USA
- University of Pennsylvania, Philadelphia, PA, USA
| | | | - Yuval Neria
- Columbia University College of Physicians & Surgeons, New York, NY, USA
- School of Psychological Sciences, Tel-Aviv University, Tel Aviv, Israel
| | | | - John C. Markowitz
- Columbia University College of Physicians & Surgeons, New York, NY, USA
- School of Psychological Sciences, Tel-Aviv University, Tel Aviv, Israel
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22
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Lecei A, van Winkel R. Hippocampal pattern separation of emotional information determining risk or resilience in individuals exposed to childhood trauma: Linking exposure to neurodevelopmental alterations and threat anticipation. Neurosci Biobehav Rev 2020; 108:160-170. [DOI: 10.1016/j.neubiorev.2019.11.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 11/15/2019] [Accepted: 11/15/2019] [Indexed: 12/29/2022]
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Lambert HK, McLaughlin KA. Impaired hippocampus-dependent associative learning as a mechanism underlying PTSD: A meta-analysis. Neurosci Biobehav Rev 2019; 107:729-749. [PMID: 31545990 DOI: 10.1016/j.neubiorev.2019.09.024] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 08/10/2019] [Accepted: 09/13/2019] [Indexed: 12/19/2022]
Abstract
Smaller hippocampal volume is associated with increased risk for PTSD following trauma, but the hippocampal functions involved remain unknown. We propose a conceptual model that identifies broad impairment in hippocampus-dependent associative learning as a vulnerability factor for PTSD. Associative learning of foreground cues and background context is required to form an integrated representation of an event. People with poor associative learning may have difficulty remembering who or what was present during a trauma, where the trauma occurred, or the sequence of events, which may contribute to PTSD symptoms. We argue that associative learning difficulties in PTSD exist for cues and context, regardless of the emotional nature of the information. This contrasts with PTSD models that focus exclusively on threat-processing or contextual-processing. In a meta-analysis, people with PTSD exhibited poor associative learning of multiple information types compared to those without PTSD. Differences were of medium effect size and similar magnitude for neutral and negative/trauma-related stimuli. We provide evidence for associative learning difficulties as a neurocognitive pathway that may contribute to PTSD.
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Affiliation(s)
- Hilary K Lambert
- Department of Psychology, University of Washington, 119A Guthrie Hall, Box 351525, Seattle, WA, 98195-1525, USA.
| | - Katie A McLaughlin
- Department of Psychology, Harvard University, William James Hall, 33 Kirkland Street, Cambridge, MA 02138, USA.
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Klaming R, Spadoni AD, Veltman DJ, Simmons AN. Expansion of hippocampal and amygdala shape in posttraumatic stress and early life stress. NEUROIMAGE-CLINICAL 2019; 24:101982. [PMID: 31437724 PMCID: PMC6706650 DOI: 10.1016/j.nicl.2019.101982] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 08/09/2019] [Accepted: 08/12/2019] [Indexed: 01/03/2023]
Abstract
OBJECTIVE The aim of this study was to examine the effect of Posttraumatic Stress Disorder (PTSD) and childhood adversity on brain structure. We assessed hippocampal and amygdala shape in veterans with varying levels of PTSD symptom severity and exposure to early life stressors (ELS). METHODS A total of 70 male veterans, who were deployed to a combat area during OIF/OEF/OND and who had been exposed to trauma during deployment, were included in the study. We applied a vertex-wise shape analysis of 3T MRI scans to measure indentation or expansion in hippocampal and amygdala shape. RESULTS Analyses showed a positive correlation between number of ELS and vertices in the right amygdala and the right hippocampus, as well as a positive correlation between PTSD symptom severity and right hippocampal vertices. There were no significant interactions between PTSD symptoms, ELS, and brain shape. DISCUSSION Results indicate a relationship between exposure to more childhood adversity and expansion in amygdala and hippocampal shape as well as between more severe PTSD symptoms and expansion in hippocampal shape. These findings may have important implications for the pathophysiology of trauma-related disorders.
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Affiliation(s)
- Ruth Klaming
- VA San Diego Healthcare System, University of California San Diego, San Diego, CA, USA; Department of Psychiatry, University of California San Diego, San Diego, CA, USA; Department of Psychiatry, VU University Medical Center, Amsterdam, The Netherlands.
| | - Andrea D Spadoni
- VA San Diego Healthcare System, University of California San Diego, San Diego, CA, USA; Department of Psychiatry, University of California San Diego, San Diego, CA, USA
| | - Dick J Veltman
- Department of Psychiatry, VU University Medical Center, Amsterdam, The Netherlands
| | - Alan N Simmons
- VA San Diego Healthcare System, University of California San Diego, San Diego, CA, USA; Department of Psychiatry, University of California San Diego, San Diego, CA, USA
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Michely J, Rigoli F, Rutledge RB, Hauser TU, Dolan RJ. Distinct Processing of Aversive Experience in Amygdala Subregions. BIOLOGICAL PSYCHIATRY: COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2019; 5:291-300. [PMID: 31542358 PMCID: PMC7059109 DOI: 10.1016/j.bpsc.2019.07.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 07/22/2019] [Accepted: 07/22/2019] [Indexed: 11/21/2022]
Abstract
Background The amygdala is an anatomically complex medial temporal brain structure whose subregions are considered to serve distinct functions. However, their precise role in mediating human aversive experience remains ill understood. Methods We used functional magnetic resonance imaging in 39 healthy volunteers with varying levels of trait anxiety to assess distinct contributions of the basolateral amygdala (BLA) and centromedial amygdala to anticipation and experience of aversive events. Additionally, we examined the relationship between any identified functional subspecialization and measures of subjective reported aversion and trait anxiety. Results Our results show that the centromedial amygdala is responsive to aversive outcomes but insensitive to predictive aversive cues. In contrast, the BLA encodes an aversive prediction error that quantifies whether cues and outcomes are worse than expected. A neural representation within the BLA for distinct threat levels was mirrored in self-reported subjective anxiety across individuals. Furthermore, high trait-anxious individuals were characterized by indiscriminately heightened BLA activity in response to aversive cues, regardless of actual threat level. Conclusions Our results demonstrate that amygdala subregions are distinctly engaged in processing of aversive experience, with elevated and undifferentiated BLA responses to threat emerging as a potential neurobiological mediator of vulnerability to anxiety disorders.
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Affiliation(s)
- Jochen Michely
- Wellcome Centre for Human Neuroimaging, University College London, London, United Kingdom; Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, United Kingdom.
| | - Francesco Rigoli
- Wellcome Centre for Human Neuroimaging, University College London, London, United Kingdom; Department of Psychology, University of London, London, United Kingdom
| | - Robb B Rutledge
- Wellcome Centre for Human Neuroimaging, University College London, London, United Kingdom; Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, United Kingdom
| | - Tobias U Hauser
- Wellcome Centre for Human Neuroimaging, University College London, London, United Kingdom; Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, United Kingdom
| | - Raymond J Dolan
- Wellcome Centre for Human Neuroimaging, University College London, London, United Kingdom; Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, United Kingdom
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Szeszko PR, Yehuda R. Magnetic resonance imaging predictors of psychotherapy treatment response in post-traumatic stress disorder: A role for the salience network. Psychiatry Res 2019; 277:52-57. [PMID: 30755338 DOI: 10.1016/j.psychres.2019.02.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 02/01/2019] [Accepted: 02/02/2019] [Indexed: 01/21/2023]
Abstract
The earliest neuroimaging studies in post-traumatic stress disorder (PTSD) utilized positron emission tomography (PET) to examine the brain's response to glucocorticoid administration given predominant neurobiological models of the stress response focusing on that neuroendocrine system. This work revealed that the anterior cingulate cortex and amygdala, which is now considered part of the salience network, play a role in treatment response, and set the stage for subsequent magnetic resonance (MR) imaging studies focused on understanding the role of the salience network in the neurobiology of treatment response in PTSD. This selective review discusses magnetic resonance (MR) imaging studies that have been used to predict treatment response to cognitive-behavioral therapy (CBT) or prolonged exposure (PE) in PTSD, which have demonstrated abnormalities in processing involving the salience network, including the amygdala, anterior cingulate cortex and insula. Increased attention to environmental cues may signal alarm resulting in hypervigilance and overactive action-monitoring for the detection of threatening stimuli and an inability to integrate concomitant emotional and sensory functions in PTSD. Successful psychotherapy treatment response in PTSD appears to involve the ability to downregulate amygdala activity to trauma-related stimuli through improved regulation of attention by the anterior cingulate cortex and concomitant internal emotional states mediated by the insula. In addition, the ability to better modulate (normalize) the salience network following psychotherapy in PTSD may be associated with better crosstalk between untargeted inner thought (i.e., task-negative network) and the ability to focus attention on stimulus-dependent demands (i.e., task positive network).
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Affiliation(s)
- Philip R Szeszko
- James J. Peters VA Medical Center, Bronx, NY, United States; Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, United States.
| | - Rachel Yehuda
- James J. Peters VA Medical Center, Bronx, NY, United States; Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, United States
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Durand F, Isaac C, Januel D. Emotional Memory in Post-traumatic Stress Disorder: A Systematic PRISMA Review of Controlled Studies. Front Psychol 2019; 10:303. [PMID: 30890976 PMCID: PMC6411692 DOI: 10.3389/fpsyg.2019.00303] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 01/30/2019] [Indexed: 01/28/2023] Open
Abstract
Background: Emotional memory is an adaptive process that improves the memorization of emotional events or stimuli. In Post-Traumatic Stress Disorder (PTSD), emotional memory may be altered, which in turn may affect symptoms. Having a clearer view of the processes of interaction between memory and emotional stimuli in PTSD may improve our knowledge of this disorder, and could create new therapeutic management tools. Thus, we performed a systematic review of the evidence of specific emotional memory in PTSD patients. Method: Following PRISMA guidelines, a systematic review of MEDLINE, PsycInfo, and ScienceDirect was undertaken to identify controlled studies on emotional memory that used cognitive tasks on PTSD patients. The initial research was conducted from June 2017 to July 2017, and search terms included: Post-Traumatic Stress Disorder; PTSD; emotional memory; emotion; emotional; memory; and episodic memory. Results: Eighteen studies reporting on 387 PTSD patients met the eligibility criteria. Among the studies selected, 11 observed specific memory processing in PTSD patients, such as a greater memorization of negative information, or a trend to false recognition of negative information. In addition, attentional and inhibition processing seem to play an important role in emotional memory in PTSD sufferers. Furthermore, other studies that did not find behavioral differences between PTSD and control groups nevertheless showed differences in both specific cerebral activities and neurohormone levels during emotional memory tasks. Conclusion: This review has several limitations, including a limited number of controlled studies, small sample sizes, different tasks and methods. Nevertheless, the results of this systematic review provide interesting information on emotional memory for clinicians and researchers, as they seem to highlight facilitated memory processing for negative information in PTSD patients. This topic needs further controlled studies with sensitive behavioral tasks. Also, future studies may evaluate emotional memory after symptom amelioration.
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Affiliation(s)
- Florence Durand
- Unité de Recherche Clinique (URC), EPS Ville Evrard, Neuilly-sur-Marne, France
- Laboratory of Neuropsychology and Psychopathology, University of Paris, Saint-Denis, France
| | - Clémence Isaac
- Unité de Recherche Clinique (URC), EPS Ville Evrard, Neuilly-sur-Marne, France
- Laboratory of Neuropsychology and Psychopathology, University of Paris, Saint-Denis, France
| | - Dominique Januel
- Unité de Recherche Clinique (URC), EPS Ville Evrard, Neuilly-sur-Marne, France
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28
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Joshi SA, Duval ER, Kubat B, Liberzon I. A review of hippocampal activation in post-traumatic stress disorder. Psychophysiology 2019; 57:e13357. [PMID: 30829407 DOI: 10.1111/psyp.13357] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 01/22/2019] [Accepted: 02/05/2019] [Indexed: 01/15/2023]
Abstract
Post-traumatic stress disorder (PTSD) is often characterized by deficits in memory encoding and retrieval and aberrant fear and extinction learning. The hippocampus plays a critical role in memory and contextual processing and has been implicated in intrinsic functional connectivity networks involved in self-referential thought and memory-related processes. This review focuses on hippocampal activation findings during memory and fear and extinction learning tasks, as well as resting state hippocampal connectivity in individuals with PTSD. A preponderance of functional neuroimaging studies to date, using memory, fear learning, and extinction tasks, report decreased or "controls comparable" hippocampal activation in individuals with PTSD, which is usually associated with poorer performance on the task imaged. Existing evidence thus raises the possibility that greater hippocampal recruitment in PTSD participants may be required for similar performance levels. Studies of resting state functional connectivity in PTSD predominantly report reduced within-network connectivity in the default mode network (DMN), as well as greater coupling between the DMN and salience network (SN) via the hippocampus. Together, these findings suggest that deficient hippocampal activation in PTSD may be associated with poorer performance during memory, extinction recall, and fear renewal tasks. Furthermore, studies of resting state connectivity implicate the hippocampus in decreased within-network DMN connectivity and greater coupling with SN regions characteristic of PTSD.
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Affiliation(s)
- Sonalee A Joshi
- Department of Psychiatry, University of Michigan Health System, Ann Arbor, Michigan
| | - Elizabeth R Duval
- Department of Psychiatry, University of Michigan Health System, Ann Arbor, Michigan
| | - Bradley Kubat
- Department of Psychiatry, University of Michigan Health System, Ann Arbor, Michigan
| | - Israel Liberzon
- Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan.,Department of Psychiatry, Texas A&M University Health Science Center, College Station, Texas
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Chen HJ, Zhang L, Ke J, Qi R, Xu Q, Zhong Y, Pan M, Li J, Lu GM, Chen F. Altered resting-state dorsal anterior cingulate cortex functional connectivity in patients with post-traumatic stress disorder. Aust N Z J Psychiatry 2019; 53:68-79. [PMID: 30453750 DOI: 10.1177/0004867418812674] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The brain functional alterations at regional and network levels in post-traumatic stress disorder patients are still unclear. This study explored brain functional alterations at regional and network levels in post-traumatic stress disorder patients with resting-state functional magnetic resonance imaging and evaluated the relationship between brain function and clinical indices in post-traumatic stress disorder. METHODS Amplitude of low-frequency fluctuation and seed-based functional connectivity analyses were conducted among typhoon survivors with ( n = 27) and without post-traumatic stress disorder ( n = 33) and healthy controls ( n = 30) to assess the spontaneous brain activity and network-level brain function. Pearson correlation analyses were performed to examine the association of brain function with clinical symptom and social support. RESULTS Both the post-traumatic stress disorder group and the trauma-exposed control group showed decreased amplitude of low-frequency fluctuation in the dorsal anterior cingulate cortex relative to the healthy control group. The post-traumatic stress disorder group showed increased dorsal anterior cingulate cortex functional connectivity with the right paracentral lobule and bilateral precentral gyrus/postcentral gyrus relative to both control groups. Both traumatized groups exhibited decreased dorsal anterior cingulate cortex functional connectivity with the right hippocampus and left cerebellum relative to the healthy control group. More decreased dorsal anterior cingulate cortex functional connectivity with the right hippocampus was found in the post-traumatic stress disorder group. The Checklist-Civilian Version score positively correlated with functional connectivity between the dorsal anterior cingulate cortex and the right paracentral lobule as well as between the dorsal anterior cingulate cortex and the right precentral gyrus/postcentral gyrus. The social support was associated with functional connectivity between the dorsal anterior cingulate cortex and the bilateral precentral gyrus/postcentral gyrus as well as the dorsal anterior cingulate cortex and the left middle frontal gyrus. CONCLUSION Trauma exposure may result in aberrant local and network-level functional connectivity in individuals with or without post-traumatic stress disorder. Altered amplitude of low-frequency fluctuation in the dorsal anterior cingulate cortex may be a predisposing risk factor for post-traumatic stress disorder development following trauma exposure. More prominent decreased dorsal anterior cingulate cortex functional connectivity with the right hippocampus might be specific in the post-traumatic stress disorder group. Improvement of social support might possibly be significant for post-traumatic stress disorder patients.
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Affiliation(s)
- Hui Juan Chen
- 1 Department of Radiology, Hainan General Hospital, Haikou, China
| | - Li Zhang
- 2 Mental Health Institute, The Second Xiangya Hospital, National Technology Institute of Psychiatry, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, China
| | - Jun Ke
- 3 Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, China.,4 Department of Radiology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Rongfeng Qi
- 3 Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Qiang Xu
- 3 Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Yuan Zhong
- 3 Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Mengjie Pan
- 1 Department of Radiology, Hainan General Hospital, Haikou, China
| | - Jianjun Li
- 1 Department of Radiology, Hainan General Hospital, Haikou, China
| | - Guang Ming Lu
- 3 Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Feng Chen
- 1 Department of Radiology, Hainan General Hospital, Haikou, China
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Hsu CMK, Kleim B, Nicholson EL, Zuj DV, Cushing PJ, Gray KE, Clark L, Felmingham KL. Sex differences in intrusive memories following trauma. PLoS One 2018; 13:e0208575. [PMID: 30521618 PMCID: PMC6283557 DOI: 10.1371/journal.pone.0208575] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 11/20/2018] [Indexed: 11/21/2022] Open
Abstract
Background A key mechanism thought to underlie Posttraumatic Stress Disorder (PTSD) is enhanced emotional memory consolidation. Recent evidence in healthy controls revealed that women have greater negative memory consolidation following stress relative to men. This study examined emotional memory consolidation in women and men with PTSD, and in trauma-exposed and non-trauma controls to test the hypothesis that emotionally negative memory consolidation would be greater in women with PTSD. Method One hundred and forty-seven men and women (47 with PTSD, 49 trauma-exposed controls, and 51 non-trauma controls) completed an emotional memory task where they looked at negative, neutral and positive images from the International Affective Picture System (IAPS). Delayed recall and an intrusive memory diary were completed two days later. Results Women displayed greater recall, and reported more negative intrusive memories than men. A gender x group interaction effect showed that both women with PTSD and trauma-exposed women reported more intrusive memories than women without trauma exposure or men. Conclusion This study provided preliminary evidence of sex differences in intrusive memories in those with PTSD as well as those with a history of trauma exposure. Future research should include measures of sex hormones to further examine sex differences on memory consolidation in the context of trauma exposure and PTSD.
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Affiliation(s)
- Chia-Ming K. Hsu
- Division of Psychology, School of Medicine, University of Tasmania, Hobart, Tasmania, Australia
- * E-mail:
| | - Birgit Kleim
- Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital Zurich, Zurich, Switzerland
| | - Emma L. Nicholson
- Division of Psychology, School of Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Daniel V. Zuj
- Division of Psychology, School of Medicine, University of Tasmania, Hobart, Tasmania, Australia
- Department of Psychology, Swansea University, Singleton Park, Wales, United Kingdom
| | - Pippa J. Cushing
- Division of Psychology, School of Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Kate E. Gray
- Division of Psychology, School of Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Latifa Clark
- Division of Psychology, School of Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Kim L. Felmingham
- School of Psychological Sciences, University of Melbourne, Parkville, Victoria, Australia
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Hall SA, Brodar KE, LaBar KS, Berntsen D, Rubin DC. Neural responses to emotional involuntary memories in posttraumatic stress disorder: Differences in timing and activity. Neuroimage Clin 2018; 19:793-804. [PMID: 30013923 PMCID: PMC6024199 DOI: 10.1016/j.nicl.2018.05.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Revised: 04/30/2018] [Accepted: 05/08/2018] [Indexed: 01/18/2023]
Abstract
Background Involuntary memories are a hallmark symptom of posttraumatic stress disorder (PTSD), but studies of the neural basis of involuntary memory retrieval in posttraumatic stress disorder (PTSD) are sparse. The study of the neural correlates of involuntary memories of stressful events in PTSD focuses on the voluntary retrieval of memories that are sometimes recalled as intrusive involuntary memories, not on involuntary retrieval while being scanned. Involuntary memory retrieval in controls has been shown to elicit activity in the parahippocampal gyrus, precuneus, inferior parietal cortex, and posterior midline regions. However, it is unknown whether involuntary memories are supported by the same mechanisms in PTSD. Because previous work has shown that both behavioral and neural responsivity is slowed in PTSD, we examined the spatiotemporal dynamics of the neural activity underlying negative and neutral involuntary memory retrieval. Methods Twenty-one individuals with PTSD and 21 non-PTSD, trauma-exposed controls performed an involuntary memory task, while undergoing a functional magnetic resonance imaging scan. Environmental sounds served as cues for well-associated pictures of negative and neutral scenes. We used a finite impulse response model to analyze temporal differences between groups in neural responses. Results Compared with controls, participants with PTSD reported more involuntary memories, which were more emotional and more vivid, but which activated a similar network of regions. However, compared to controls, individuals with PTSD showed delayed neural responsivity in this network and increased vmPFC/ACC activity for negative > neutral stimuli. Conclusions The similarity between PTSD and controls in neural substrates underlying involuntary memories suggests that, unlike voluntary memories, involuntary memories elicit similar activity in regions critical for memory retrieval. Further, the delayed neural responsivity for involuntary memories in PTSD suggests that factors affecting cognition in PTSD, like increased fatigue, or avoidance behaviors could do so by delaying activity in regions necessary for cognitive processing. Finally, compared to neutral memories, negative involuntary memories elicit hyperactivity in the vmPFC, whereas the vmPFC is typically shown to be hypoactive in PTSD during voluntary memory retrieval. These patterns suggest that considering both the temporal dynamics of cognitive processes as well as involuntary cognitive processes would improve existing neurobiological models of PTSD.
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Key Words
- ACC, anterior cingulate cortex
- FDR, false detection rate
- FIR, finite impulse response
- FWE, family-wise error
- Finite impulse response (FIR)
- Functional magnetic resonance imaging (fMRI)
- IAPS, International Affective Picture System
- IPC, inferior parietal cortex
- Involuntary memory
- MTL, medial temporal lobes
- Memory network
- PCC, posterior cingulate cortex
- PTSD, posttraumatic stress disorder
- Posttraumatic stress disorder (PTSD)
- SPGR, spoiled gradient recalled
- SPM, Statistical Parametric Mapping
- TE, echo time
- TI, inverse recovery time
- TR, repetition time
- Ventromedial prefrontal cortex (vmPFC)
- vmPFC, ventromedial prefrontal cortex
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Affiliation(s)
- Shana A Hall
- Department of Psychology & Neuroscience, University of North Carolina, Chapel Hill, United States; Department of Psychology & Neuroscience, Duke University, United States.
| | - Kaitlyn E Brodar
- Department of Psychology, University of Miami, United States; Department of Psychology & Neuroscience, Duke University, United States
| | - Kevin S LaBar
- Department of Psychology & Neuroscience, Duke University, United States
| | - Dorthe Berntsen
- Center on Autobiographical Memory Research, Aarhus University, Denmark
| | - David C Rubin
- Department of Psychology & Neuroscience, Duke University, United States; Center on Autobiographical Memory Research, Aarhus University, Denmark
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Dahlgren MK, Laifer LM, VanElzakker MB, Offringa R, Hughes KC, Staples-Bradley LK, Dubois SJ, Lasko NB, Hinojosa CA, Orr SP, Pitman RK, Shin LM. Diminished medial prefrontal cortex activation during the recollection of stressful events is an acquired characteristic of PTSD. Psychol Med 2018; 48:1128-1138. [PMID: 28893331 PMCID: PMC5847462 DOI: 10.1017/s003329171700263x] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Previous research has shown relatively diminished medial prefrontal cortex activation and heightened psychophysiological responses during the recollection of personal events in post-traumatic stress disorder (PTSD), but the origin of these abnormalities is unknown. Twin studies provide the opportunity to determine whether such abnormalities reflect familial vulnerabilities, result from trauma exposure, or are acquired characteristics of PTSD. METHODS In this case-control twin study, 26 male identical twin pairs (12 PTSD; 14 non-PTSD) discordant for PTSD and combat exposure recalled and imagined trauma-unrelated stressful and neutral life events using a standard script-driven imagery paradigm during functional magnetic resonance imaging and concurrent skin conductance measurement. RESULTS Diminished activation in the medial prefrontal cortex during Stressful v. Neutral script-driven imagery was observed in the individuals with PTSD, relative to other groups. CONCLUSIONS Diminished medial prefrontal cortex activation during Stressful v. Neutral script-driven imagery may be an acquired characteristic of PTSD. If replicated, this finding could be used prospectively to inform diagnosis and the assessment of treatment response.
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Affiliation(s)
- M. Kathryn Dahlgren
- Department of Psychology, Tufts University, Medford, MA
- Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | | | - Michael B. VanElzakker
- Department of Psychology, Tufts University, Medford, MA
- Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - Reid Offringa
- Department of Psychology, Tufts University, Medford, MA
| | - Katherine C. Hughes
- Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, MA
| | | | | | - Natasha B. Lasko
- Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - Cecilia A. Hinojosa
- Department of Psychology, Tufts University, Medford, MA
- Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - Scott P. Orr
- Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - Roger K. Pitman
- Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - Lisa M. Shin
- Department of Psychology, Tufts University, Medford, MA
- Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA
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Abstract
OBJECTIVE To examine the temporal consistency of self-reported deployment-related traumatic brain injury (TBI) and its association with posttraumatic stress disorder (PTSD) symptom severity. SETTING In-person interviews at US Army installations (postdeployment); phone interviews (long-term follow-up). PARTICIPANTS A total of 378 US Army soldiers and veterans deployed to Iraq; 14.3% (n = 54) reported TBI with loss of consciousness during an index deployment. DESIGN Participants were evaluated after returning from deployment and again 5 to 9 years later. MAIN MEASURES Temporal consistency of TBI endorsement based on TBI screening interviews; PTSD Checklist, Civilian Version. RESULTS The concordance of deployment-related TBI endorsement from the postdeployment to long-term follow-up assessment was moderate (κ = 0.53). Of the 54 participants reporting (predominantly mild) TBI occurring during an index deployment, 32 endorsed TBI inconsistently over time. More severe PTSD symptoms at postdeployment assessment were independently associated with discordant reporting (P = .0004); each 10-point increase in PCL scores increasing odds of discordance by 69% (odds ratio = 1.69; 95% confidence interval, 1.26-2.26). CONCLUSIONS Deployment-related TBI may not be reported reliably over time, particularly among war-zone veterans with greater PTSD symptoms. Results of screening evaluations for TBI history should be viewed with caution in the context of PTSD symptom history.
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Doss MK, Weafer J, Gallo DA, de Wit H. MDMA Impairs Both the Encoding and Retrieval of Emotional Recollections. Neuropsychopharmacology 2018; 43:791-800. [PMID: 28825422 PMCID: PMC5809786 DOI: 10.1038/npp.2017.171] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 07/19/2017] [Accepted: 08/06/2017] [Indexed: 12/21/2022]
Abstract
The psychoactive drug ±3,4-methylenedioxymethamphetamine (MDMA) is increasingly used for its perceived emotional effects (eg, prosociality, empathy, psychotherapy), but surprisingly little research has been aimed at identifying the effect of the drug on emotional episodic memory in humans. Here, we report the first double-blind placebo-controlled study to examine the effects of MDMA on emotional memory separately during encoding and retrieval in healthy participants. Participants viewed emotionally negative, neutral, and positive pictures and their labels. Forty-eight hours later, they were given cued recollection and recognition memory tests designed to assess recollection and familiarity for the studied pictures. Participants were randomly assigned to one of three groups who received MDMA (1 mg/kg) either during encoding (Encoding group; N=20), retrieval (Retrieval group; N=20), or neither (Placebo group; N=20). Although MDMA administered at either phase did not affect overall memory accuracy, it did alter the recollection of details associated specifically with emotional memories as estimated using a dual process signal detection analysis of confidence judgments and subjective 'remember' judgments. In the Encoding group, MDMA reduced recollection estimates for negative and positive pictures but had little to no effect on neutral items or familiarity estimates. There was evidence for similar trends in the Retrieval group. These findings indicate that MDMA attenuates the encoding and retrieval of salient details from emotional events, consistent with the idea that its potential therapeutic effects for treating posttraumatic stress disorder are related to altering emotional memory.
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Affiliation(s)
- Manoj K Doss
- Department of Psychology, University of Chicago, Chicago, IL, USA,Department of Psychology, The University of Chicago, 5848 S. University Ave., Beecher 308, Chicago, IL 60637, USA. Tel: +1 773 702 4376, E-mail:
| | - Jessica Weafer
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA
| | - David A Gallo
- Department of Psychology, University of Chicago, Chicago, IL, USA
| | - Harriet de Wit
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA
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Abstract
Posttraumatic stress disorder (PTSD) is a devastating disorder, linked to profound mental, physical, occupational, and functional impairment. In addition, it is a highly complex disorder, characterized by symptom heterogeneity across multiple domains. Nevertheless, emotion dysregulation arising from the exaggerated response to threat or from the inability to regulate negative emotional states plays a defining role in the pathophysiology of PTSD. In order to improve our understanding of how emotion dysregulation manifests in this illness, functional neuroimaging research over the past 20 years provides great insight into underlying neuroanatomy of each component of emotion dysregulation in the context of PTSD. While prior reviews exist on the topic of neuroimaging findings in PTSD, the present review synthesizes that work through the lens of emotion and its regulation. Studies that employed tasks of emotional responding and symptom provocation, implicit regulation (e.g., emotional Stroop and interference), explicit regulation (e.g., cognitive reappraisal), and fear conditioning/extinction were reviewed. Findings demonstrate that emotion dysregulation in PTSD arises from complications within a large neurocircuitry involving the amygdala, insula, hippocampus, anterior cingulate cortex, and prefrontal cortex. Although an exaggerated response in the amygdala and insula to negative emotional triggers is pervasive, PTSD is also marked by deficient appraisal, resolution, and management of negative emotional states subserved by the anterior cingulate cortex and prefrontal cortex during regulation. These findings further support the importance of studying emotion-regulation deficits in tandem with exaggerated symptom provocation in order to better understand the constellation of symptoms present in those with PTSD.
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Stevens JS, Reddy R, Kim YJ, van Rooij SJH, Ely TD, Hamann S, Ressler KJ, Jovanovic T. Episodic memory after trauma exposure: Medial temporal lobe function is positively related to re-experiencing and inversely related to negative affect symptoms. NEUROIMAGE-CLINICAL 2017; 17:650-658. [PMID: 29204343 PMCID: PMC5709292 DOI: 10.1016/j.nicl.2017.11.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 10/31/2017] [Accepted: 11/18/2017] [Indexed: 12/18/2022]
Abstract
Hippocampal structure is particularly sensitive to trauma and other stressors. However, previous findings linking hippocampal function with trauma-related psychopathology have been mixed. Heterogeneity in psychological responses to trauma has not been considered with respect to hippocampal function and may contribute to mixed findings. To address these issues, we examined associations between data-driven symptom dimensions and episodic memory formation, a key function of the hippocampus, in a trauma-exposed sample. Symptom dimensions were defined using principal components analysis (PCA) in 3881 trauma-exposed African-American women recruited from primary care waiting rooms of a large urban hospital. Hippocampal and amygdala function were subsequently investigated in an fMRI study of episodic memory formation in a subset of 54 women. Participants viewed scenes with neutral, negative, and positive content during fMRI, and completed a delayed cued recall task. PCA analysis produced five symptom dimensions interpreted as reflecting negative affect, somatic symptoms, re-experiencing, hyper-arousal, and numbing. Re-experiencing was the only symptom type associated with hippocampal function, predicting increased memory encoding-related activation in the hippocampus as well as the amygdala. In contrast, the negative affect component predicted lower amygdala activation for subsequently recalled scenes, and lower functional coupling with other important memory-related regions including the precuneus, inferior frontal gyrus, and occipital cortex. Symptom dimensions were not related to hippocampal volume. The fMRI findings for re-experiencing versus negative affect parallel differences in behavioral memory phenomena in PTSD versus MDD, and highlight a need for more complex models of trauma-related pathology.
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Affiliation(s)
- Jennifer S Stevens
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA.
| | - Renuka Reddy
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Ye Ji Kim
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Sanne J H van Rooij
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Timothy D Ely
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Stephan Hamann
- Department of Psychology, Emory University, Atlanta, GA, USA
| | - Kerry J Ressler
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA; Harvard Medical School, Boston, MA, USA; McLean Hospital, Belmont, MA, USA
| | - Tanja Jovanovic
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
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Lazarov A, Zhu X, Suarez-Jimenez B, Rutherford BR, Neria Y. Resting-state functional connectivity of anterior and posterior hippocampus in posttraumatic stress disorder. J Psychiatr Res 2017; 94. [PMID: 28633076 PMCID: PMC5605418 DOI: 10.1016/j.jpsychires.2017.06.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Posttraumatic stress disorder (PTSD) has been associated with altered resting-state functional connectivity (rs-FC) of several brain regions within the salience (SN) and default-mode (DMN) networks, including the hippocampus. However, most rs-FC studies have not focused primarily on the hippocampus, nor have they appreciated its structural heterogeneity, despite clear evidence for a dissociation between posterior and anterior hippocampal connectivity. Here, we examine rs-FC of anterior and posterior hippocampus with key regions in the SN (amygdala, insula, and dorsal anterior cingulate cortex/pre-supplementary motor area) and DMN (ventromedial prefrontal cortex, posterior cingulate cortex, and precuneus) previously implicated in PTSD, using a seed-based approach. Resting-state magnetic resonance images were obtained from 48 PTSD patients and 34 trauma-exposed healthy participants (TEHC). Results indicated no group differences when examining the hippocampus as a whole. However, examining the anterior and posterior hippocampus revealed a loss of anterior to posterior connectivity differentiation in PTSD patients. The PTSD group also demonstrated lower negative connectivity of the posterior hippocampus-precuneus pathway compared with the TEHC group. Finally, as differences in anterior and posterior hippocampus connectivity have been also related to age, we performed a secondary analysis exploring the association between age and posterior- and anterior-hippocampus connectivity in both groups. Results showed that among PTSD patients, increased age had the effect of normalizing posterior hippocampus-precuneus and hippocampus-posterior cingulate cortex connectivity, whereas no such effect was noted for the control group. These findings highlight the need for PTSD connectivity research to consider sub-parts of the hippocampus and to account for age-related connectivity differences.
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Affiliation(s)
- Amit Lazarov
- Department of Psychiatry, Columbia University Medical Center, 1051 Riverside Drive, New York, NY 10032, USA; New York State Psychiatric Institute, 1051 Riverside Drive, New York, NY 10032, USA.
| | - Xi Zhu
- Department of Psychiatry, Columbia University Medical Center, 1051 Riverside Drive, New York, NY 10032, USA; New York State Psychiatric Institute, 1051 Riverside Drive, New York, NY 10032, USA.
| | - Benjamin Suarez-Jimenez
- Department of Psychiatry, Columbia University Medical Center, 1051 Riverside Drive, New York, NY 10032, USA; New York State Psychiatric Institute, 1051 Riverside Drive, New York, NY 10032, USA.
| | - Bret R Rutherford
- Department of Psychiatry, Columbia University Medical Center, 1051 Riverside Drive, New York, NY 10032, USA; New York State Psychiatric Institute, 1051 Riverside Drive, New York, NY 10032, USA.
| | - Yuval Neria
- Department of Psychiatry, Columbia University Medical Center, 1051 Riverside Drive, New York, NY 10032, USA; New York State Psychiatric Institute, 1051 Riverside Drive, New York, NY 10032, USA; Department of Epidemiology, Columbia University Medical Center, 722 west 168th st., New York, NY 10032, USA.
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Zhang XD, Yin Y, Hu XL, Duan L, Qi R, Xu Q, Lu GM, Li LJ. Altered default mode network configuration in posttraumatic stress disorder after earthquake: A resting-stage functional magnetic resonance imaging study. Medicine (Baltimore) 2017; 96:e7826. [PMID: 28906364 PMCID: PMC5604633 DOI: 10.1097/md.0000000000007826] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The neural substrates of posttraumatic stress disorder (PTSD) are still not fully elucidated. Hence, this study is to explore topological alterations of the default mode network (DMN) in victims with PTSD after a magnitude of 8.0 earthquake using resting-state functional magnetic resonance imaging (rs-fMRI).This study was approved by the local ethical review board, and all participants signed written informed consent. Sixty-two PTSD victims from the 2008 Sichuan earthquake and 62 matched exposed controls underwent rs-fMRI. PTSD was diagnosed by Clinician-Administered PTSD Scale, and underwent PTSD Checklist-Civilian Version for symptom scoring. The DMN was analyzed by using graph theoretical approaches. Further, Pearson correlation analysis was performed to correlate neuroimaging metrics to neuropsychological scores in victims with PTSD.Victims with PTSD showed decreased DMN functional connectivity strength between the right superior frontal gyrus and left inferior parietal lobule (IPL), and showed increased functional connectivity between the right IPL and precuneus or left posterior cingulate cortex. It was also found that victims with PTSD exhibited decreased nodal efficiency in right superior frontal gyrus and precuneus, and increased nodal efficiency in right hippocampus/parahippocampus. Apart from that, PTSD showed higher nodal degree in bilateral hippocampus/parahippocampus. In addition, the functional connectivity strength between the right IPL and precuneus correlated negatively to the avoid scores (r = -0.26, P = .04).This study implicates alteration of topological features on the DMN in PTSD victims after major earthquake, and provides new insights into DMN malfunction in PTSD based on graph theory.
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Affiliation(s)
- Xiao-Dong Zhang
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing
| | - Yan Yin
- The Seventh People's Hospital of Hangzhou, Hangzhou, Zhejiang
| | - Xiao-Lei Hu
- Mental Health Institute, The Second Xiangya Hospital of Central South University, Hunan, People's Republic of China
| | - Lian Duan
- Mental Health Institute, The Second Xiangya Hospital of Central South University, Hunan, People's Republic of China
| | - Rongfeng Qi
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing
| | - Qiang Xu
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing
| | - Guang-Ming Lu
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing
| | - Ling-Jiang Li
- Mental Health Institute, The Second Xiangya Hospital of Central South University, Hunan, People's Republic of China
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Gvozdanovic GA, Stämpfli P, Seifritz E, Rasch B. Neural correlates of experimental trauma memory retrieval. Hum Brain Mapp 2017; 38:3592-3602. [PMID: 28419641 DOI: 10.1002/hbm.23613] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 03/16/2017] [Accepted: 04/04/2017] [Indexed: 02/01/2023] Open
Abstract
OBJECTIVES Traumatic memories such as intrusions and flashbacks play a major role in the development and maintenance of post-traumatic stress disorder (PTSD). A thorough understanding of the neural mechanisms underlying traumatic memories is indispensable for precise diagnosis, for personalized treatment and prevention. In particular, the identification of early neural predictor variables for intrusion development shortly after trauma exposure requires detailed investigation. EXPERIMENTAL DESIGN Here, we examined the neural correlates of early experimental trauma memory retrieval in a traumatic film paradigm in 42 young healthy females, using both implicit and explicit retrieval tasks. PRINCIPAL OBSERVATIONS We show that implicit experimental trauma retrieval specifically involved the retrosplenial cortex and the anterior cingulate cortex (ACC), while both retrieval tasks resulted in trauma-related activity in the posterior cingulate cortex (PCC) and the precuneus. Importantly, neural activity early after experimental trauma exposure predicted later intrusion development, with independent contributions from activity in the retrosplenial cortex (implicit retrieval) and the PCC (explicit retrieval). Additional analyses revealed a stronger connectivity between the bilateral amygdala and the supplementary motor area, precentral and paracentral lobule for the control group compared to the experimental trauma group. CONCLUSIONS Our study gives new insights in the neural correlates of experimental trauma memory retrieval and their predictive value for subsequent symptom development. Our results could provide the basis for personalized early treatment and prevention of PTSD. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc. Hum Brain Mapp 38:3592-3602, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Geraldine A Gvozdanovic
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zürich, Zürich, Switzerland.,Division of Biopsychology, Institute of Psychology, University of Zürich, Zürich, Switzerland
| | - Philipp Stämpfli
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zürich, Zürich, Switzerland
| | - Erich Seifritz
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zürich, Zürich, Switzerland.,Division of Biopsychology, Zurich Center for Interdisciplinary Sleep Research (ZiS), University of Zürich, Switzerland
| | - Björn Rasch
- Division of Biopsychology, Zurich Center for Interdisciplinary Sleep Research (ZiS), University of Zürich, Switzerland.,Division of Cognitive Biopsychology and Methods, Department of Psychology, University of Fribourg, Fribourg, Switzerland
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The Transition of Acute Postoperative Pain to Chronic Pain: An Integrative Overview of Research on Mechanisms. THE JOURNAL OF PAIN 2017; 18:359.e1-359.e38. [DOI: 10.1016/j.jpain.2016.11.004] [Citation(s) in RCA: 180] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 10/15/2016] [Accepted: 11/16/2016] [Indexed: 01/01/2023]
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Hayes JP, Logue MW, Reagan A, Salat D, Wolf EJ, Sadeh N, Spielberg JM, Sperbeck E, Hayes SM, McGlinchey RE, Milberg WP, Verfaellie M, Stone A, Schichman SA, Miller MW. COMT Val158Met polymorphism moderates the association between PTSD symptom severity and hippocampal volume. J Psychiatry Neurosci 2017; 42:95-102. [PMID: 28234210 PMCID: PMC5373706 DOI: 10.1503/jpn.150339] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Memory-based alterations are among the hallmark symptoms of posttraumatic stress disorder (PTSD) and may be associated with the integrity of the hippocampus. However, neuroimaging studies of hippocampal volume in individuals with PTSD have yielded inconsistent results, raising the possibility that various moderators, such as genetic factors, may influence this association. We examined whether the catechol-O-methyltransferase (COMT) Val158Met polymorphism, which has previously been shown to be associated with hippocampal volume in healthy individuals, moderates the association between PTSD and hippocampal volume. METHODS Recent war veterans underwent structural MRI on a 3 T scanner. We extracted volumes of the right and left hippocampus using FreeSurfer and adjusted them for individual differences in intracranial volume. We assessed PTSD severity using the Clinician-Administered PTSD Scale. Hierarchical linear regression was used to model the genotype (Val158Met polymorphism) × PTSD severity interaction and its association with hippocampal volume. RESULTS We included 146 white, non-Hispanic recent war veterans (90% male, 53% with diagnosed PTSD) in our analyses. A significant genotype × PTSD symptom severity interaction emerged such that individuals with greater current PTSD symptom severity who were homozygous for the Val allele showed significant reductions in left hippocampal volume. LIMITATIONS The direction of proposed effects is unknown, thus precluding definitive assessment of whether differences in hippocampal volume reflect a consequence of PTSD, a pre-existing characteristic, or both. CONCLUSION Our findings suggest that the COMT polymorphism moderates the association between PTSD and hippocampal volume. These results highlight the role that the dopaminergic system has in brain structure and suggest a possible mechanism for memory disturbance in individuals with PTSD.
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Affiliation(s)
- Jasmeet P. Hayes
- Correspondence to: J.P. Hayes, National Center for PTSD (116B-2), VA Boston Healthcare System, 150 S. Huntington Ave., Boston MA 02130;
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Li Y, Hou X, Wei D, Du X, Zhang Q, Liu G, Qiu J. Long-Term Effects of Acute Stress on the Prefrontal-Limbic System in the Healthy Adult. PLoS One 2017; 12:e0168315. [PMID: 28045980 PMCID: PMC5207406 DOI: 10.1371/journal.pone.0168315] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 11/30/2016] [Indexed: 11/19/2022] Open
Abstract
Most people are exposed to at least one traumatic event during the course of their lives, but large numbers of people do not develop posttraumatic stress disorders. Although previous studies have shown that repeated and chronic stress change the brain’s structure and function, few studies have focused on the long-term effects of acute stressful exposure in a nonclinical sample, especially the morphology and functional connectivity changes in brain regions implicated in emotional reactivity and emotion regulation. Forty-one months after the 5/12 Wenchuan earthquake, we investigated the effects of trauma exposure on the structure and functional connectivity of the brains of trauma-exposed healthy individuals compared with healthy controls matched for age, sex, and education. We then used machine-learning algorithms with the brain structural features to distinguish between the two groups at an individual level. In the trauma-exposed healthy individuals, our results showed greater gray matter density in prefrontal-limbic brain systems, including the dorsal anterior cingulate cortex, medial prefrontal cortex, amygdala and hippocampus, than in the controls. Further analysis showed stronger amygdala-hippocampus functional connectivity in the trauma-exposed healthy compared to the controls. Our findings revealed that survival of traumatic experiences, without developing PTSD, was associated with greater gray matter density in the prefrontal-limbic systems related to emotional regulation.
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Affiliation(s)
- Yu Li
- Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, China
- School of Psychology, Southwest University, Chongqing, China
| | - Xin Hou
- Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, China
- School of Psychology, Southwest University, Chongqing, China
| | - Dongtao Wei
- Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, China
- School of Psychology, Southwest University, Chongqing, China
| | - Xue Du
- Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, China
- School of Psychology, Southwest University, Chongqing, China
| | - Qinglin Zhang
- Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, China
- School of Psychology, Southwest University, Chongqing, China
| | - Guangyuan Liu
- College of Electronic and Information Engineering, Chongqing, China
| | - Jiang Qiu
- Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, China
- School of Psychology, Southwest University, Chongqing, China
- * E-mail:
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43
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Growth hormone biases amygdala network activation after fear learning. Transl Psychiatry 2016; 6:e960. [PMID: 27898076 PMCID: PMC5290350 DOI: 10.1038/tp.2016.203] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 07/07/2016] [Accepted: 07/18/2016] [Indexed: 01/27/2023] Open
Abstract
Prolonged stress exposure is a risk factor for developing posttraumatic stress disorder, a disorder characterized by the 'over-encoding' of a traumatic experience. A potential mechanism by which this occurs is through upregulation of growth hormone (GH) in the amygdala. Here we test the hypotheses that GH promotes the over-encoding of fearful memories by increasing the number of neurons activated during memory encoding and biasing the allocation of neuronal activation, one aspect of the process by which neurons compete to encode memories, to favor neurons that have stronger inputs. Viral overexpression of GH in the amygdala increased the number of amygdala cells activated by fear memory formation. GH-overexpressing cells were especially biased to express the immediate early gene c-Fos after fear conditioning, revealing strong autocrine actions of GH in the amygdala. In addition, we observed dramatically enhanced dendritic spine density in GH-overexpressing neurons. These data elucidate a previously unrecognized autocrine role for GH in the regulation of amygdala neuron function and identify specific mechanisms by which chronic stress, by enhancing GH in the amygdala, may predispose an individual to excessive fear memory formation.
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Patel R, Girard TA, Pukay-Martin N, Monson C. Preferential recruitment of the basolateral amygdala during memory encoding of negative scenes in posttraumatic stress disorder. Neurobiol Learn Mem 2016; 130:170-6. [DOI: 10.1016/j.nlm.2016.02.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 01/28/2016] [Accepted: 02/04/2016] [Indexed: 10/22/2022]
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Abstract
OBJECTIVE Fear conditioning seems to account for the acquisition of post-traumatic stress disorder, whereas conscious recall of events in aftermath of trauma reflects episodic memory. Studies show that both fear conditioning and episodic memory are heritable, but no study has evaluated whether they reflect common or separate genetic factors. To this end, we studied episodic memory and fear conditioning in 173 healthy twin pairs using visual stimuli predicting unconditioned electric shocks. METHODS Fear conditioning acquisition and extinction was determined using conditioned visual stimuli predicting unconditioned mild electric shocks, whereas electrodermal activity served as the fear learning index. Episodic memory was evaluated using cued recall of pictorial stimuli unrelated to conditioning. We used multivariate structural equation modeling to jointly analyze memory performance and acquisition as well as extinction of fear conditioning. RESULTS Best-fit twin models estimated moderate genetic loadings for conditioning and memory measures, with no genetic covariation between them. CONCLUSION Individual differences in fear conditioning and episodic memory reflect distinct genetically influenced processes, suggesting that the genetic risk for learning-induced anxiety disorders includes at least two memory-related genetic factors. These findings are consistent with the facts that the two separate learning forms are distant in their evolutionary development, involve different brain mechanisms, and support that genetically independent memory systems are pivotal in the development and maintenance of syndromes related to fear learning.
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46
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Perusini JN, Meyer EM, Long VA, Rau V, Nocera N, Avershal J, Maksymetz J, Spigelman I, Fanselow MS. Induction and Expression of Fear Sensitization Caused by Acute Traumatic Stress. Neuropsychopharmacology 2016; 41:45-57. [PMID: 26329286 PMCID: PMC4677128 DOI: 10.1038/npp.2015.224] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 07/20/2015] [Accepted: 07/21/2015] [Indexed: 02/08/2023]
Abstract
Fear promotes adaptive responses to threats. However, when the level of fear is not proportional to the level of threat, maladaptive fear-related behaviors characteristic of anxiety disorders result. Post-traumatic stress disorder develops in response to a traumatic event, and patients often show sensitized reactions to mild stressors associated with the trauma. Stress-enhanced fear learning (SEFL) is a rodent model of this sensitized responding, in which exposure to a 15-shock stressor nonassociatively enhances subsequent fear conditioning training with only a single trial. We examined the role of corticosterone (CORT) in SEFL. Administration of the CORT synthesis blocker metyrapone prior to the stressor, but not at time points after, attenuated SEFL. Moreover, CORT co-administered with metyrapone rescued SEFL. However, CORT alone without the stressor was not sufficient to produce SEFL. In these same animals, we then looked for correlates of SEFL in terms of changes in excitatory receptor expression. Western blot analysis of the basolateral amygdala (BLA) revealed an increase in the GluA1 AMPA receptor subunit that correlated with SEFL. Thus, CORT is permissive to trauma-induced changes in BLA function.
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Affiliation(s)
- Jennifer N Perusini
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA, USA
| | - Edward M Meyer
- Division of Oral Biology & Medicine, School of Dentistry, University of California at Los Angeles, Los Angeles, CA, USA
| | - Virginia A Long
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA, USA
| | - Vinuta Rau
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA, USA
| | - Nathaniel Nocera
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA, USA
| | - Jacob Avershal
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA, USA
| | - James Maksymetz
- Division of Oral Biology & Medicine, School of Dentistry, University of California at Los Angeles, Los Angeles, CA, USA
| | - Igor Spigelman
- Division of Oral Biology & Medicine, School of Dentistry, University of California at Los Angeles, Los Angeles, CA, USA
| | - Michael S Fanselow
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA, USA
- Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, Los Angeles, CA, USA
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Behavioral and central correlates of contextual fear learning and contextual modulation of cued fear in posttraumatic stress disorder. Int J Psychophysiol 2015; 98:584-93. [DOI: 10.1016/j.ijpsycho.2015.06.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 05/29/2015] [Accepted: 06/26/2015] [Indexed: 01/04/2023]
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48
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Saur L, Baptista PPA, Bagatini PB, Neves LT, de Oliveira RM, Vaz SP, Ferreira K, Machado SA, Mestriner RG, Xavier LL. Experimental Post-traumatic Stress Disorder Decreases Astrocyte Density and Changes Astrocytic Polarity in the CA1 Hippocampus of Male Rats. Neurochem Res 2015; 41:892-904. [DOI: 10.1007/s11064-015-1770-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 10/20/2015] [Accepted: 11/11/2015] [Indexed: 12/16/2022]
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Veer IM, Oei NYL, van Buchem MA, Spinhoven P, Elzinga BM, Rombouts SARB. Evidence for smaller right amygdala volumes in posttraumatic stress disorder following childhood trauma. Psychiatry Res 2015. [PMID: 26211620 DOI: 10.1016/j.pscychresns.2015.07.016] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Hippocampus and amygdala volumes in posttraumatic stress disorder (PTSD) related to childhood trauma are relatively understudied, albeit the potential importance to the disorder. Whereas some studies reported smaller hippocampal volumes, little evidence was found for abnormal amygdala volumes. Here we investigated hippocampus and amygdala volumes and shapes in an adult sample of PTSD patients related to childhood trauma. T1-weighted MR images were acquired from 12 female PTSD patients with trauma related to physical, sexual, and/or emotional abuse before age 18, and from 12 matched controls. Hippocampus and amygdala were segmented, and volumes were calculated and corrected for the total intracranial volume. Additionally, a shape analysis was done on the surface of the structures to explore abnormalities in specific subnuclei. Smaller right amygdala volumes were found in PTSD patients as compared with the controls. This difference appeared to be located specifically in the basolateral and superficial nuclei groups. Severity of sexual abuse during childhood was negatively correlated with the size of the amygdala. No difference in hippocampal volumes was found. Although our results are not conclusive, traumatic events in childhood might impede normal development of the amygdala, which could render a person more vulnerable to develop PTSD later in life.
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Affiliation(s)
- Ilya M Veer
- Leiden Institute for Brain and Cognition (LIBC), Leiden, The Netherlands; Charité Universitätsmedizin Berlin, Division of Mind and Brain Research, Department of Psychiatry and Psychotherapy, Berlin, Germany.
| | - Nicole Y L Oei
- Leiden Institute for Brain and Cognition (LIBC), Leiden, The Netherlands; University of Amsterdam, Addiction, Development, and Psychopathology (ADAPT) Lab, Amsterdam, The Netherlands; University of Amsterdam, Amsterdam Brain and Cognition, Amsterdam, The Netherlands
| | - Mark A van Buchem
- Leiden Institute for Brain and Cognition (LIBC), Leiden, The Netherlands; Leiden University Medical Center, Department of Radiology, Leiden, The Netherlands
| | - Philip Spinhoven
- Leiden Institute for Brain and Cognition (LIBC), Leiden, The Netherlands; Leiden University - Institute of Psychology, Leiden, The Netherlands; Leiden University Medical Center, Department of Psychiatry, Leiden, The Netherlands
| | - Bernet M Elzinga
- Leiden Institute for Brain and Cognition (LIBC), Leiden, The Netherlands; Leiden University - Institute of Psychology, Leiden, The Netherlands
| | - Serge A R B Rombouts
- Leiden Institute for Brain and Cognition (LIBC), Leiden, The Netherlands; Leiden University Medical Center, Department of Radiology, Leiden, The Netherlands; Leiden University - Institute of Psychology, Leiden, The Netherlands
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50
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Tschiffely A, Ahlers S, Norris J. Examining the relationship between blast-induced mild traumatic brain injury and posttraumatic stress-related traits. J Neurosci Res 2015; 93:1769-77. [DOI: 10.1002/jnr.23641] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 08/12/2015] [Accepted: 08/12/2015] [Indexed: 01/04/2023]
Affiliation(s)
- A.E. Tschiffely
- Department of Neurotrauma; Operational and Undersea Medicine Directorate, Naval Medical Research Center; Silver Spring Maryland
- Henry M. Jackson Foundation; Bethesda Maryland
| | - S.T. Ahlers
- Department of Neurotrauma; Operational and Undersea Medicine Directorate, Naval Medical Research Center; Silver Spring Maryland
| | - J.N. Norris
- Department of Neurotrauma; Operational and Undersea Medicine Directorate, Naval Medical Research Center; Silver Spring Maryland
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