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Craven AR, Dwyer G, Ersland L, Kazimierczak K, Noeske R, Sandøy LB, Johnsen E, Hugdahl K. GABA, glutamatergic dynamics and BOLD contrast assessed concurrently using functional MRS during a cognitive task. NMR IN BIOMEDICINE 2024; 37:e5065. [PMID: 37897259 DOI: 10.1002/nbm.5065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 09/29/2023] [Accepted: 10/03/2023] [Indexed: 10/30/2023]
Abstract
A recurring issue in functional neuroimaging is how to link task-driven haemodynamic blood oxygen level dependent functional MRI (BOLD-fMRI) responses to underlying neurochemistry at the synaptic level. Glutamate and γ-aminobutyric acid (GABA), the major excitatory and inhibitory neurotransmitters respectively, are typically measured with MRS sequences separately from fMRI, in the absence of a task. The present study aims to resolve this disconnect, developing acquisition and processing techniques to simultaneously assess GABA, glutamate and glutamine (Glx) and BOLD in relation to a cognitive task, at 3 T. Healthy subjects (N = 81) performed a cognitive task (Eriksen flanker), which was presented visually in a task-OFF, task-ON block design, with individual event onset timing jittered with respect to the MRS readout. fMRS data were acquired from the medial anterior cingulate cortex during task performance, using an adapted MEGA-PRESS implementation incorporating unsuppressed water-reference signals at a regular interval. These allowed for continuous assessment of BOLD activation, through T2 *-related changes in water linewidth. BOLD-fMRI data were additionally acquired. A novel linear model was used to extract modelled metabolite spectra associated with discrete functional stimuli, building on well established processing and quantification tools. Behavioural outcomes from the flanker task, and activation patterns from the BOLD-fMRI sequence, were as expected from the literature. BOLD response assessed through fMRS showed a significant correlation with fMRI, specific to the fMRS-targeted region of interest; fMRS-assessed BOLD additionally correlated with lengthening of response time in the incongruent flanker condition. While no significant task-related changes were observed for GABA+, a significant increase in measured Glx levels (~8.8%) was found between task-OFF and task-ON periods. These findings verify the efficacy of our protocol and analysis pipelines for the simultaneous assessment of metabolite dynamics and BOLD. As well as establishing a robust basis for further work using these techniques, we also identify a number of clear directions for further refinement in future studies.
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Affiliation(s)
- Alexander R Craven
- Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway
- Department of Clinical Engineering, Haukeland University Hospital, Bergen, Norway
- NORMENT Center of Excellence, Haukeland University Hospital, Bergen, Norway
| | - Gerard Dwyer
- Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway
- NORMENT Center of Excellence, Haukeland University Hospital, Bergen, Norway
| | - Lars Ersland
- Department of Clinical Engineering, Haukeland University Hospital, Bergen, Norway
- NORMENT Center of Excellence, Haukeland University Hospital, Bergen, Norway
| | | | | | - Lydia Brunvoll Sandøy
- Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Erik Johnsen
- NORMENT Center of Excellence, Haukeland University Hospital, Bergen, Norway
- Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | - Kenneth Hugdahl
- Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway
- Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
- Department of Radiology, Haukeland University Hospital, Bergen, Norway
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2
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Ruehl RM, Flanagin VL, Ophey L, Raiser TM, Seiderer K, Ertl M, Conrad J, Zu Eulenburg P. The human egomotion network. Neuroimage 2022; 264:119715. [PMID: 36334557 DOI: 10.1016/j.neuroimage.2022.119715] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 10/18/2022] [Accepted: 10/25/2022] [Indexed: 11/07/2022] Open
Abstract
All volitional movement in a three-dimensional space requires multisensory integration, in particular of visual and vestibular signals. Where and how the human brain processes and integrates self-motion signals remains enigmatic. Here, we applied visual and vestibular self-motion stimulation using fast and precise whole-brain neuroimaging to delineate and characterize the entire cortical and subcortical egomotion network in a substantial cohort (n=131). Our results identify a core egomotion network consisting of areas in the cingulate sulcus (CSv, PcM/pCi), the cerebellum (uvula), and the temporo-parietal cortex including area VPS and an unnamed region in the supramarginal gyrus. Based on its cerebral connectivity pattern and anatomical localization, we propose that this region represents the human homologue of macaque area 7a. Whole-brain connectivity and gradient analyses imply an essential role of the connections between the cingulate sulcus and the cerebellar uvula in egomotion perception. This could be via feedback loops involved updating visuo-spatial and vestibular information. The unique functional connectivity patterns of PcM/pCi hint at central role in multisensory integration essential for the perception of self-referential spatial awareness. All cortical egomotion hubs showed modular functional connectivity with other visual, vestibular, somatosensory and higher order motor areas, underlining their mutual function in general sensorimotor integration.
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Affiliation(s)
- Ria Maxine Ruehl
- Department of Neurology, University Hospital Munich, Ludwig-Maximilians-University Munich, Marchionini Str. 15, 81377 Munich, Germany; German Center for Vertigo and Balance Disorders, IFB-LMU, University Hospital Munich, Ludwig-Maximilians-University Munich, Marchionini Str. 15, 81377 Munich, Germany.
| | - Virginia L Flanagin
- Department of Neurology, University Hospital Munich, Ludwig-Maximilians-University Munich, Marchionini Str. 15, 81377 Munich, Germany; German Center for Vertigo and Balance Disorders, IFB-LMU, University Hospital Munich, Ludwig-Maximilians-University Munich, Marchionini Str. 15, 81377 Munich, Germany; Graduate School of Systemic Neurosciences, Department of Biology II and Neurobiology, Großhaderner Str. 2, 82151 Planegg-Martinsried, Ludwig-Maximilians-University Munich, Germany
| | - Leoni Ophey
- German Center for Vertigo and Balance Disorders, IFB-LMU, University Hospital Munich, Ludwig-Maximilians-University Munich, Marchionini Str. 15, 81377 Munich, Germany
| | - Theresa Marie Raiser
- Department of Neurology, University Hospital Munich, Ludwig-Maximilians-University Munich, Marchionini Str. 15, 81377 Munich, Germany; German Center for Vertigo and Balance Disorders, IFB-LMU, University Hospital Munich, Ludwig-Maximilians-University Munich, Marchionini Str. 15, 81377 Munich, Germany
| | - Katharina Seiderer
- German Center for Vertigo and Balance Disorders, IFB-LMU, University Hospital Munich, Ludwig-Maximilians-University Munich, Marchionini Str. 15, 81377 Munich, Germany
| | - Matthias Ertl
- Institute of Psychology and Inselspital, Fabrikstrasse 8, 3012 Bern, University of Bern, Switzerland
| | - Julian Conrad
- Department of Neurology, University Hospital Munich, Ludwig-Maximilians-University Munich, Marchionini Str. 15, 81377 Munich, Germany; German Center for Vertigo and Balance Disorders, IFB-LMU, University Hospital Munich, Ludwig-Maximilians-University Munich, Marchionini Str. 15, 81377 Munich, Germany; Department of Neurology, Theodor-Kutze Ufer 1-3, 68167 Mannheim, Medical Faculty Mannheim, University of Heidelberg, Germany
| | - Peter Zu Eulenburg
- German Center for Vertigo and Balance Disorders, IFB-LMU, University Hospital Munich, Ludwig-Maximilians-University Munich, Marchionini Str. 15, 81377 Munich, Germany; Graduate School of Systemic Neurosciences, Department of Biology II and Neurobiology, Großhaderner Str. 2, 82151 Planegg-Martinsried, Ludwig-Maximilians-University Munich, Germany; Institute for Neuroradiology, University Hospital Munich, Marchionini Str. 15, 81377 Munich, Ludwig-Maximilians-University Munich, Germany
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3
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Gool JK, Fronczek R, Bosma P, van der Meer JN, van der Werf YD, Lammers GJ. Enhanced Visual Cortex Activation in People With Narcolepsy Type 1 During Active Sleep Resistance: An fMRI-EEG Study. Front Neurosci 2022; 16:904820. [PMID: 35833089 PMCID: PMC9271668 DOI: 10.3389/fnins.2022.904820] [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: 03/25/2022] [Accepted: 05/26/2022] [Indexed: 11/18/2022] Open
Abstract
The brain activation patterns related to sleep resistance remain to be discovered in health and disease. The maintenance of wakefulness test (MWT) is an objective neuropsychological assessment often used to assess an individual’s ability to resist sleep. It is frequently used in narcolepsy type 1, a disorder characterized by impaired sleep-wake control and the inability to resist daytime sleep. We investigated the neural correlates of active sleep resistance in 12 drug-free people with narcolepsy type 1 and 12 healthy controls. Simultaneous fMRI-EEG measurements were recorded during five cycles of two alternating conditions of active sleep resistance and waking rest. Cleaned EEG signals were used to verify wakefulness and task adherence. Pooling both subject groups, significantly higher fMRI activation when actively resisting sleep was seen in the brainstem, superior cerebellum, bilateral thalamus and visual cortices. In controls the activation clusters were generally smaller compared to patients and no significant activation was seen in the brainstem. Formal comparison between groups only found a significantly higher left primary visual cortex activation in patients during active sleep resistance. The active sleep resistance paradigm is a feasible fMRI task to study sleep resistance and induces evident arousal- and visual-related activity. Significantly higher left primary visual cortical activation in patients could be caused by an enhanced need of visual focus to resist sleep, or reflecting a more rapid descent in their level of alertness when resting.
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Affiliation(s)
- Jari K. Gool
- Sleep-Wake Centre, Stichting Epilepsie Instellingen Netherland (SEIN), Heemstede, Netherlands
- Department of Neurology, Leiden University Medical Centre, Leiden, Netherlands
- Anatomy & Neurosciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Amsterdam Neuroscience, Mood, Anxiety, Psychosis, Sleep & Stress Program, Amsterdam, Netherlands
- *Correspondence: Jari K. Gool,
| | - Rolf Fronczek
- Sleep-Wake Centre, Stichting Epilepsie Instellingen Netherland (SEIN), Heemstede, Netherlands
- Department of Neurology, Leiden University Medical Centre, Leiden, Netherlands
| | - Peter Bosma
- Sleep-Wake Centre, Stichting Epilepsie Instellingen Netherland (SEIN), Heemstede, Netherlands
| | - Johan N. van der Meer
- Department of Radiology and Nuclear Medicine, University of Amsterdam, Amsterdam, Netherlands
| | - Ysbrand D. van der Werf
- Anatomy & Neurosciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Amsterdam Neuroscience, Mood, Anxiety, Psychosis, Sleep & Stress Program, Amsterdam, Netherlands
| | - Gert Jan Lammers
- Sleep-Wake Centre, Stichting Epilepsie Instellingen Netherland (SEIN), Heemstede, Netherlands
- Department of Neurology, Leiden University Medical Centre, Leiden, Netherlands
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4
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Kong Y, Yang B, Zhang J, Dong C. Research progress on hydroxyl protection of iridoid glycosides. Aust J Chem 2022. [DOI: 10.1071/ch21260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Iridoids, an important active ingredient, are widely distributed in varieties of Chinese herbal medicines and have varieties of pharmacological activities, such as anti-tumor, hypoglycemic, anti-inflammatory and so on, most of which exist in the form of glycosides in nature. However, its clinical application is limited by poor lipid solubility, low bioavailability and short half-life. It is necessary to optimize the structure of iridoids. It is hard to modify the hydroxyl groups at specific sites because iridoid glycosides are polyhydroxy compounds and very complex. In this paper, the words of ‘Iridoid glycosides’ and ‘Hydroxyl protection’ were used as the keywords, more than 200 articles from 1965 to 2021 were obtained from databases, such as CNKI, PubMed, Scifinder and so on. Finally, 60 articles were selected to summarize the hydroxyl protection of iridoid glycosides, which will provide a theoretical basis for their structural modification and stimulate their application potential in the field of drug research and development.
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5
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Chen X, Fan X, Hu Y, Zuo C, Whitfield-Gabrieli S, Holt D, Gong Q, Yang Y, Pizzagalli DA, Du F, Ongur D. Regional GABA Concentrations Modulate Inter-network Resting-state Functional Connectivity. Cereb Cortex 2020; 29:1607-1618. [PMID: 29608677 DOI: 10.1093/cercor/bhy059] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 01/30/2018] [Indexed: 02/05/2023] Open
Abstract
Coordinated activity within and differential activity between large-scale neuronal networks such as the default mode network (DMN) and the control network (CN) is a critical feature of brain organization. The CN usually exhibits activations in response to cognitive tasks while the DMN shows deactivations; in addition, activity between the two networks is anti-correlated at rest. To address this issue, we used functional MRI to measure whole-brain BOLD signal during resting-state and task-evoked conditions, and MR spectroscopy (MRS) to quantify GABA and glutamate concentrations, in nodes within the DMN and CN (MPFC and DLPFC, respectively) in 19 healthy individuals at 3 Tesla. We found that GABA concentrations in the MPFC were significantly associated with DMN deactivation during a working memory task and with anti-correlation between DMN and CN at rest and during task performance, while GABA concentrations in the DLPFC weakly modulated DMN-CN anti-correlation in the opposite direction. Highlighting specificity, glutamate played a less significant role related to brain activity. These findings indicate that GABA in the MPFC is potentially involved in orchestrating between-network brain activity at rest and during task performance.
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Affiliation(s)
- Xi Chen
- McLean Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA, USA.,Psychotic Disorders Division, McLean Hospital, Harvard Medical School, Belmont, MA, USA
| | - Xiaoying Fan
- Psychotic Disorders Division, McLean Hospital, Harvard Medical School, Belmont, MA, USA
| | - Yuzheng Hu
- Neuroimaging Research Branch, National Institute on Drug Abuse, Intramural Research Programs, National Institute of Health, Baltimore, MD, USA
| | - Chun Zuo
- McLean Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA, USA
| | - Susan Whitfield-Gabrieli
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Daphne Holt
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Qiyong Gong
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, China
| | - Yihong Yang
- Neuroimaging Research Branch, National Institute on Drug Abuse, Intramural Research Programs, National Institute of Health, Baltimore, MD, USA
| | - Diego A Pizzagalli
- McLean Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA, USA.,Center For Depression, Anxiety and Stress Research, McLean Hospital, Harvard Medical School, Belmont, MA, USA
| | - Fei Du
- McLean Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA, USA.,Psychotic Disorders Division, McLean Hospital, Harvard Medical School, Belmont, MA, USA
| | - Dost Ongur
- Psychotic Disorders Division, McLean Hospital, Harvard Medical School, Belmont, MA, USA
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6
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Moreno-Ortega M, Prudic J, Rowny S, Patel GH, Kangarlu A, Lee S, Grinband J, Palomo T, Perera T, Glasser MF, Javitt DC. Resting state functional connectivity predictors of treatment response to electroconvulsive therapy in depression. Sci Rep 2019; 9:5071. [PMID: 30911075 PMCID: PMC6433903 DOI: 10.1038/s41598-019-41175-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 02/26/2019] [Indexed: 02/07/2023] Open
Abstract
There is increasing focus on use of resting-state functional connectivity (RSFC) analyses to subtype depression and to predict treatment response. To date, identification of RSFC patterns associated with response to electroconvulsive therapy (ECT) remain limited, and focused on interactions between dorsal prefrontal and regions of the limbic or default-mode networks. Deficits in visual processing are reported in depression, however, RSFC with or within the visual network have not been explored in recent models of depression. Here, we support prior studies showing in a sample of 18 patients with depression that connectivity between dorsal prefrontal and regions of the limbic and default-mode networks serves as a significant predictor. In addition, however, we demonstrate that including visual connectivity measures greatly increases predictive power of the RSFC algorithm (>80% accuracy of remission). These exploratory results encourage further investigation into visual dysfunction in depression, and use of RSFC algorithms incorporating the visual network in prediction of response to both ECT and transcranial magnetic stimulation (TMS), offering a new framework for the development of RSFC-guided TMS interventions in depression.
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Affiliation(s)
- M Moreno-Ortega
- Division of Experimental Therapeutics, Department of Psychiatry, New York State Psychiatric Institute/Columbia University Medical Center, New York, NY, USA. .,Centro de Investigacion Biomedica en Red de Salud Mental (CIBERSAM), Madrid, Spain.
| | - J Prudic
- Division of Experimental Therapeutics, Department of Psychiatry, New York State Psychiatric Institute/Columbia University Medical Center, New York, NY, USA
| | - S Rowny
- Division of Experimental Therapeutics, Department of Psychiatry, New York State Psychiatric Institute/Columbia University Medical Center, New York, NY, USA
| | - G H Patel
- Division of Experimental Therapeutics, Department of Psychiatry, New York State Psychiatric Institute/Columbia University Medical Center, New York, NY, USA
| | - A Kangarlu
- Department of Psychiatry, Radiology and Biomedical Engineering, Columbia University, New York, NY, USA
| | - S Lee
- Department of Psychiatry and Biostatistics, New York State Psychiatric Institute/Columbia University, New York, NY, USA
| | - J Grinband
- Division of Experimental Therapeutics, Department of Psychiatry, New York State Psychiatric Institute/Columbia University Medical Center, New York, NY, USA
| | - T Palomo
- Centro de Investigacion Biomedica en Red de Salud Mental (CIBERSAM), Madrid, Spain.,Department of Psychiatry, Complutense University, Madrid, Spain
| | - T Perera
- Division of Experimental Therapeutics, Department of Psychiatry, New York State Psychiatric Institute/Columbia University Medical Center, New York, NY, USA
| | - M F Glasser
- Departments of Radiology and Neuroscience, Washington University Medical School, St. Louis, MO, USA
| | - D C Javitt
- Division of Experimental Therapeutics, Department of Psychiatry, New York State Psychiatric Institute/Columbia University Medical Center, New York, NY, USA
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7
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Qin P, Duncan NW, Chen DYT, Chen CJ, Huang LK, Huang Z, Lin CYE, Wiebking C, Yang CM, Northoff G, Lane TJ. Vascular-metabolic and GABAergic Inhibitory Correlates of Neural Variability Modulation. A Combined fMRI and PET Study. Neuroscience 2018. [PMID: 29530810 DOI: 10.1016/j.neuroscience.2018.02.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Neural activity varies continually from moment to moment. Such temporal variability (TV) has been highlighted as a functionally specific brain property playing a fundamental role in cognition. We sought to investigate the mechanisms involved in TV changes between two basic behavioral states, namely having the eyes open (EO) or eyes closed (EC) in vivo in humans. To these ends we acquired BOLD fMRI, ASL, and [18F]-fluoro-deoxyglucose PET in a group of healthy participants (n = 15), along with BOLD fMRI and [18F]-flumazenil PET in a separate group (n = 19). Focusing on an EO- vs EC-sensitive region in the occipital cortex (identified in an independent sample), we show that TV is constrained in the EO condition compared to EC. This reduction is correlated with an increase in energy consumption and with regional GABAA receptor density. This suggests that the modulation of TV by behavioral state involves an increase in overall neural activity that is related to an increased effect from GABAergic inhibition in addition to any excitatory changes. These findings contribute to our understanding of the mechanisms underlying activity variability in the human brain and its control.
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Affiliation(s)
- Pengmin Qin
- Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, China; Graduate Institute of Humanities in Medicine, Taipei Medical University, Taipei, Taiwan; Brain and Consciousness Research Centre, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan; Centre for Studies of Psychological Applications, South China Normal University, Guangzhou, China; School of Psychology, South China Normal University, Guangzhou, China
| | - Niall W Duncan
- Graduate Institute of Humanities in Medicine, Taipei Medical University, Taipei, Taiwan; Brain and Consciousness Research Centre, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan; Centre for Cognition and Brain Disorders, Hangzhou Normal University, Hangzhou, China.
| | - David Yen-Ting Chen
- Brain and Consciousness Research Centre, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan; Department of Radiology, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan
| | - Chi-Jen Chen
- Department of Radiology, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan
| | - Li-Kai Huang
- Department of Neurology, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan
| | - Zirui Huang
- Mind, Brain Imaging and Neuroethics Research Unit, Institute of Mental Health Research, University of Ottawa, Ottawa, Canada
| | | | - Christine Wiebking
- Applied Emotion and Motivation Research, Institute for Psychology and Education, Universität Ulm, Ulm, Germany
| | - Che-Ming Yang
- Department of Nuclear Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan
| | - Georg Northoff
- Graduate Institute of Humanities in Medicine, Taipei Medical University, Taipei, Taiwan; Brain and Consciousness Research Centre, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan; Department of Neurology, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan; University of Ottawa Brain and Mind Research Institute, Centre for Neural Dynamics, Faculty of Medicine, University of Ottawa, Ottawa, Canada; Mental Health Centre, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China
| | - Timothy J Lane
- Graduate Institute of Humanities in Medicine, Taipei Medical University, Taipei, Taiwan; Brain and Consciousness Research Centre, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan; Research Center for Mind, Brain, and Learning, National Chengchi University, Taipei, Taiwan.
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8
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GABAergic effect on resting-state functional connectivity: Dynamics under pharmacological antagonism. Neuroimage 2017; 149:53-62. [DOI: 10.1016/j.neuroimage.2017.01.040] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 12/06/2016] [Accepted: 01/17/2017] [Indexed: 11/19/2022] Open
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Thompson GJ, Riedl V, Grimmer T, Drzezga A, Herman P, Hyder F. The Whole-Brain "Global" Signal from Resting State fMRI as a Potential Biomarker of Quantitative State Changes in Glucose Metabolism. Brain Connect 2016; 6:435-47. [PMID: 27029438 DOI: 10.1089/brain.2015.0394] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The evolution of functional magnetic resonance imaging to resting state (R-fMRI) allows measurement of changes in brain networks attributed to state changes, such as in neuropsychiatric diseases versus healthy controls. Since these networks are observed by comparing normalized R-fMRI signals, it is difficult to determine the metabolic basis of such group differences. To investigate the metabolic basis of R-fMRI network differences within a normal range, eyes open versus eyes closed in healthy human subjects was used. R-fMRI was recorded simultaneously with fluoro-deoxyglucose positron emission tomography (FDG-PET). Higher baseline FDG was observed in the eyes open state. Variance-based metrics calculated from R-fMRI did not match the baseline shift in FDG. Functional connectivity density (FCD)-based metrics showed a shift similar to the baseline shift of FDG, however, this was lost if R-fMRI "nuisance signals" were regressed before FCD calculation. Average correlation with the mean R-fMRI signal across the whole brain, generally regarded as a "nuisance signal," also showed a shift similar to the baseline of FDG. Thus, despite lacking a baseline itself, changes in whole-brain correlation may reflect changes in baseline brain metabolism. Conversely, variance-based metrics may remain similar between states due to inherent region-to-region differences overwhelming the differences between normal physiological states. As most previous studies have excluded the spatial means of R-fMRI metrics from their analysis, this work presents the first evidence of a potential R-fMRI biomarker for baseline shifts in quantifiable metabolism between brain states.
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Affiliation(s)
- Garth J Thompson
- 1 Magnetic Resonance Research Center (MRRC), Yale University , New Haven, Connecticut.,2 Department of Radiology and Biomedical Imaging, Yale University , New Haven, Connecticut
| | - Valentin Riedl
- 3 Department of Neuroradiology, Technische Universität München , München, Germany .,4 Department of Nuclear Medicine, Technische Universität München , München, Germany .,5 Neuroimaging Center, Technische Universität München , München, Germany
| | - Timo Grimmer
- 5 Neuroimaging Center, Technische Universität München , München, Germany .,6 Department of Psychiatry, Technische Universität München , München, Germany
| | | | - Peter Herman
- 1 Magnetic Resonance Research Center (MRRC), Yale University , New Haven, Connecticut.,2 Department of Radiology and Biomedical Imaging, Yale University , New Haven, Connecticut.,8 Quantitative Neuroscience with Magnetic Resonance (QNMR) Core Center, Yale University , New Haven, Connecticut
| | - Fahmeed Hyder
- 1 Magnetic Resonance Research Center (MRRC), Yale University , New Haven, Connecticut.,2 Department of Radiology and Biomedical Imaging, Yale University , New Haven, Connecticut.,8 Quantitative Neuroscience with Magnetic Resonance (QNMR) Core Center, Yale University , New Haven, Connecticut.,9 Department of Biomedical Engineering, Yale University , New Haven, Connecticut
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10
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Duncan NW, Hayes DJ, Wiebking C, Tiret B, Pietruska K, Chen DQ, Rainville P, Marjańska M, Ayad O, Doyon J, Hodaie M, Northoff G. Negative childhood experiences alter a prefrontal-insular-motor cortical network in healthy adults: A preliminary multimodal rsfMRI-fMRI-MRS-dMRI study. Hum Brain Mapp 2015; 36:4622-37. [PMID: 26287448 PMCID: PMC4827445 DOI: 10.1002/hbm.22941] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 07/21/2015] [Accepted: 08/05/2015] [Indexed: 11/07/2022] Open
Abstract
Research in humans and animals has shown that negative childhood experiences (NCE) can have long-term effects on the structure and function of the brain. Alterations have been noted in grey and white matter, in the brain's resting state, on the glutamatergic system, and on neural and behavioural responses to aversive stimuli. These effects can be linked to psychiatric disorder such as depression and anxiety disorders that are influenced by excessive exposure to early life stressors. The aim of the current study was to investigate the effect of NCEs on these systems. Resting state functional MRI (rsfMRI), aversion task fMRI, glutamate magnetic resonance spectroscopy (MRS), and diffusion magnetic resonance imaging (dMRI) were combined with the Childhood Trauma Questionnaire (CTQ) in healthy subjects to examine the impact of NCEs on the brain. Low CTQ scores, a measure of NCEs, were related to higher resting state glutamate levels and higher resting state entropy in the medial prefrontal cortex (mPFC). CTQ scores, mPFC glutamate and entropy, correlated with neural BOLD responses to the anticipation of aversive stimuli in regions throughout the aversion-related network, with strong correlations between all measures in the motor cortex and left insula. Structural connectivity strength, measured using mean fractional anisotropy, between the mPFC and left insula correlated to aversion-related signal changes in the motor cortex. These findings highlight the impact of NCEs on multiple inter-related brain systems. In particular, they highlight the role of a prefrontal-insular-motor cortical network in the processing and responsivity to aversive stimuli and its potential adaptability by NCEs.
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Affiliation(s)
- Niall W. Duncan
- Graduate Institute of Humanities in Medicine, Taipei Medical UniversityTaipeiTaiwan
- Brain and Consciousness Research Center, Taipei Medical University‐Shuang Ho HospitalNew Taipei CityTaiwan
- Centre for Cognition and Brain DisordersHangzhou Normal UniversityHangzhouChina
- Mind, Brain Imaging and Neuroethics Research Unit, Institute of Mental Health Research, University of OttawaOttawaCanada
| | - Dave J. Hayes
- Division of Neurosurgery, Department of SurgeryUniversity of Toronto and Division of Brain Imaging and Behaviour Systems Neuroscience, Toronto Western Research InstituteTorontoOntarioCanada
| | - Christine Wiebking
- Cluster of Excellence in Cognitive Sciences, Department of Sociology of Physical Activity and HealthUniversity of PotsdamPotsdamGermany
| | - Brice Tiret
- Functional Neuroimaging Unit and Department of PsychologyUniversité de MontréalMontréalCanada
| | - Karin Pietruska
- Faculté de médecine dentaire, Université de MontréalMontréalCanada
| | - David Q. Chen
- Division of Neurosurgery, Department of SurgeryUniversity of Toronto and Division of Brain Imaging and Behaviour Systems Neuroscience, Toronto Western Research InstituteTorontoOntarioCanada
| | - Pierre Rainville
- Faculté de médecine dentaire, Université de MontréalMontréalCanada
| | - Małgorzata Marjańska
- Center for Magnetic Resonance Research and Department of RadiologyUniversity of MinnesotaMinneapolisMinnesota
| | - Omar Ayad
- Graduate Institute of Humanities in Medicine, Taipei Medical UniversityTaipeiTaiwan
| | - Julien Doyon
- Functional Neuroimaging Unit and Department of PsychologyUniversité de MontréalMontréalCanada
| | - Mojgan Hodaie
- Division of Neurosurgery, Department of SurgeryUniversity of Toronto and Division of Brain Imaging and Behaviour Systems Neuroscience, Toronto Western Research InstituteTorontoOntarioCanada
| | - Georg Northoff
- Graduate Institute of Humanities in Medicine, Taipei Medical UniversityTaipeiTaiwan
- Brain and Consciousness Research Center, Taipei Medical University‐Shuang Ho HospitalNew Taipei CityTaiwan
- Centre for Cognition and Brain DisordersHangzhou Normal UniversityHangzhouChina
- Mind, Brain Imaging and Neuroethics Research Unit, Institute of Mental Health Research, University of OttawaOttawaCanada
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11
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Qin P, Wu X, Duncan NW, Bao W, Tang W, Zhang Z, Hu J, Jin Y, Wu X, Gao L, Lu L, Guan Y, Lane T, Huang Z, Bodien YG, Giacino JT, Mao Y, Northoff G. GABAA receptor deficits predict recovery in patients with disorders of consciousness: A preliminary multimodal [(11) C]Flumazenil PET and fMRI study. Hum Brain Mapp 2015; 36:3867-77. [PMID: 26147065 DOI: 10.1002/hbm.22883] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2015] [Revised: 06/05/2015] [Accepted: 06/12/2015] [Indexed: 11/11/2022] Open
Abstract
OBJECTIVES Disorders of consciousness (DoC)-that is, unresponsive wakefulness syndrome/vegetative state and minimally conscious state-are debilitating conditions for which no reliable markers of consciousness recovery have yet been identified. Evidence points to the GABAergic system being altered in DoC, making it a potential target as such a marker. EXPERIMENTAL DESIGN In our preliminary study, we used [(11) C]Flumazenil positron emission tomography to establish global GABAA receptor binding potential values and the local-to-global (LTG) ratio of these for specific regions. These values were then compared between DoC patients and healthy controls. In addition, they were correlated with behavioral improvements for the patients between the time of scanning and 3 months later. Functional magnetic resonance imaging resting-state functional connectivity was also calculated and the same comparisons made. PRINCIPAL OBSERVATIONS lobal GABAA receptor binding was reduced in DoC, as was the LTG ratio in specifically the supragenual anterior cingulate. Both of these measures correlated with behavioral improvement after 3 months. In contrast to these measures of GABAA receptor binding, functional connectivity did not correlate with behavioral improvement. CONCLUSIONS Our preliminary findings point toward GABAA receptor binding being a marker of consciousness recovery in DoC.
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Affiliation(s)
- Pengmin Qin
- Graduate Institute of Humanities in Medicine, Taipei Medical University, Taipei, Taiwan.,Institute of Mental Health Research, University of Ottawa, Ottawa, Canada.,Brain and Consciousness Research Centre, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan
| | - Xuehai Wu
- Neurosurgery Department, Huashan Hospital, Fudan University, Shanghai, China
| | - Niall W Duncan
- Graduate Institute of Humanities in Medicine, Taipei Medical University, Taipei, Taiwan.,Institute of Mental Health Research, University of Ottawa, Ottawa, Canada.,Brain and Consciousness Research Centre, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan.,Centre for Cognition and Brain Disorders (CCBD), Hangzhou Normal University, Hangzhou, China
| | - Weiqi Bao
- PET/CT Centre, Huashan Hospital, Fudan University, Shanghai, China
| | - Weijun Tang
- Radiologic Department of Huashan Hospital, Fudan University, Shanghai, China
| | - Zhengwei Zhang
- PET/CT Centre, Huashan Hospital, Fudan University, Shanghai, China
| | - Jin Hu
- Neurosurgery Department, Huashan Hospital, Fudan University, Shanghai, China
| | - Yi Jin
- Neurosurgery Department, Huashan Hospital, Fudan University, Shanghai, China
| | - Xing Wu
- Neurosurgery Department, Huashan Hospital, Fudan University, Shanghai, China
| | - Liang Gao
- Neurosurgery Department, Huashan Hospital, Fudan University, Shanghai, China
| | - Lu Lu
- Antai Hospital, Shanghai, China
| | - Yihui Guan
- PET/CT Centre, Huashan Hospital, Fudan University, Shanghai, China
| | - Timothy Lane
- Institute of Mental Health Research, University of Ottawa, Ottawa, Canada.,Brain and Consciousness Research Centre, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan
| | - Zirui Huang
- Institute of Mental Health Research, University of Ottawa, Ottawa, Canada
| | - Yelena G Bodien
- Spaulding Rehabilitation Hospital, Charlestown, Massachusetts
| | | | - Ying Mao
- Neurosurgery Department, Huashan Hospital, Fudan University, Shanghai, China
| | - Georg Northoff
- Graduate Institute of Humanities in Medicine, Taipei Medical University, Taipei, Taiwan.,Institute of Mental Health Research, University of Ottawa, Ottawa, Canada.,Brain and Consciousness Research Centre, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan.,Centre for Cognition and Brain Disorders (CCBD), Hangzhou Normal University, Hangzhou, China.,Research Centre for Mind, Brain and Learning, National Chengchi University, Taipei, Taiwan
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12
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Associations of regional GABA and glutamate with intrinsic and extrinsic neural activity in humans—a review of multimodal imaging studies. Neurosci Biobehav Rev 2014; 47:36-52. [PMID: 25066091 DOI: 10.1016/j.neubiorev.2014.07.016] [Citation(s) in RCA: 153] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 06/30/2014] [Accepted: 07/17/2014] [Indexed: 01/04/2023]
Abstract
The integration of multiple imaging modalities is becoming an increasingly well used research strategy for studying the human brain. The neurotransmitters glutamate and GABA particularly lend themselves towards such studies. This is because these transmitters are ubiquitous throughout the cortex, where they are the key constituents of the inhibition/excitation balance, and because they can be easily measured in vivo through magnetic resonance spectroscopy, as well as with select positron emission tomography approaches. How these transmitters underly functional responses measured with techniques such as fMRI and EEG remains unclear though, and was the target of this review. Consistently shown in the literature was a negative correlation between GABA concentrations and stimulus-induced activity within the measured region. Also consistently found was a positive correlation between glutamate concentrations and inter-regional activity relationships, both during tasks and rest. These findings are outlined along with results from populations with mental disorders to give an overview of what brain imaging has suggested to date about the biochemical underpinnings of functional activity in health and disease. We conclude that the combination of functional and biochemical imaging in humans is an increasingly informative approach that does however require a number of key methodological and interpretive issues be addressed before can meet its potential.
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13
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Abnormal GABAergic function and negative affect in schizophrenia. Neuropsychopharmacology 2014; 39:1000-8. [PMID: 24154667 PMCID: PMC3924534 DOI: 10.1038/npp.2013.300] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 10/06/2013] [Accepted: 10/07/2013] [Indexed: 01/25/2023]
Abstract
Deficits in the γ-aminobutyric acid (GABA) system have been reported in postmortem studies of schizophrenia, and therapeutic interventions in schizophrenia often involve potentiation of GABA receptors (GABAR) to augment antipsychotic therapy and treat negative affect such as anxiety. To map GABAergic mechanisms associated with processing affect, we used a benzodiazepine challenge while subjects viewed salient visual stimuli. Fourteen stable, medicated schizophrenia/schizoaffective patients and 13 healthy comparison subjects underwent functional magnetic resonance imaging using the blood oxygenation level-dependent (BOLD) technique while they viewed salient emotional images. Subjects received intravenous lorazepam (LRZ; 0.01 mg/kg) or saline in a single-blinded, cross-over design (two sessions separated by 1-3 weeks). A predicted group by drug interaction was noted in the dorsal medial prefrontal cortex (dmPFC) as well as right superior frontal gyrus and left and right occipital regions, such that psychosis patients showed an increased BOLD signal to LRZ challenge, rather than the decreased signal exhibited by the comparison group. A main effect of reduced BOLD signal in bilateral occipital areas was noted across groups. Consistent with the role of the dmPFC in processing emotion, state negative affect positively correlated with the response to the LRZ challenge in the dmPFC for the patients and comparison subjects. The altered response to LRZ challenge is consistent with altered inhibition predicted by postmortem findings of altered GABAR in schizophrenia. These results also suggest that negative affect in schizophrenia/schizoaffective disorder is associated-directly or indirectly-with GABAergic function on a continuum with normal behavior.
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14
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Sandberg K, Blicher JU, Dong MY, Rees G, Near J, Kanai R. Occipital GABA correlates with cognitive failures in daily life. Neuroimage 2013; 87:55-60. [PMID: 24188817 PMCID: PMC3907676 DOI: 10.1016/j.neuroimage.2013.10.059] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 10/14/2013] [Accepted: 10/26/2013] [Indexed: 11/26/2022] Open
Abstract
The brain has limited capacity, and so selective attention enhances relevant incoming information while suppressing irrelevant information. This process is not always successful, and the frequency of such cognitive failures varies to a large extent between individuals. Here we hypothesised that individual differences in cognitive failures might be reflected in inhibitory processing in the sensory cortex. To test this hypothesis, we measured GABA in human visual cortex using MR spectroscopy and found a negative correlation between occipital GABA (GABA +/Cr ratio) and cognitive failures as measured by an established cognitive failures questionnaire (CFQ). For a second site in parietal cortex, no correlation between CFQ score and GABA +/Cr ratio was found, thus establishing the regional specificity of the link between occipital GABA and cognitive failures. We further found that grey matter volume in the left superior parietal lobule (SPL) correlated with cognitive failures independently from the impact of occipital GABA and together, occipital GABA and SPL grey matter volume statistically explained around 50% of the individual variability in daily cognitive failures. We speculate that the amount of GABA in sensory areas may reflect the potential capacity to selectively suppress irrelevant information already at the sensory level, or alternatively that GABA influences the specificity of neural representations in visual cortex thus improving the effectiveness of successful attentional modulation. GABA/Cr ratio was measured for an occipital and a parietal voxel. Cognitive failures were measured using the cognitive failures questionnaire (CFQ). Cognitive failures in daily life correlate with occipital GABA/Cr ratio only. Parietal (lSPL) grey matter volume also correlated with cognitive failures. Together, the two factors statistically explain 51% of individual CFQ variability.
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Affiliation(s)
- Kristian Sandberg
- Cognitive Neuroscience Research Unit, Aarhus University Hospital, Noerrebrogade 44, Building 10G, 8000 Aarhus C, Denmark; UCL Institute of Cognitive Neuroscience, University College London, 17 Queen Square, WC1N 3AR London, UK; Hammel Neurorehabilitation and Research Centre, Aarhus University Hospital, Voldbyvej 15, 8540 Hammel, Denmark.
| | - Jakob Udby Blicher
- Hammel Neurorehabilitation and Research Centre, Aarhus University Hospital, Voldbyvej 15, 8540 Hammel, Denmark; Center for Functionally Integrative Neuroscience, Aarhus University Hospital, Noerrebrogade 44, Building 10G, 8000 Aarhus C, Denmark
| | - Mia Yuan Dong
- Cognitive Neuroscience Research Unit, Aarhus University Hospital, Noerrebrogade 44, Building 10G, 8000 Aarhus C, Denmark
| | - Geraint Rees
- UCL Institute of Cognitive Neuroscience, University College London, 17 Queen Square, WC1N 3AR London, UK; Wellcome Trust Centre for Neuroimaging, Institute of Neurology, 12 Queen Square, WC1N 3AR London, UK
| | - Jamie Near
- Douglas Mental Health University Institute and Department of Psychiatry, McGill University, 1033 Pine Avenue West, Montreal, QC H3A 1A1, Canada; FMRIB Centre, University of Oxford, OxfordOX3 9DU, UK
| | - Ryota Kanai
- UCL Institute of Cognitive Neuroscience, University College London, 17 Queen Square, WC1N 3AR London, UK; School of Psychology, Sackler Centre for Consciousness Science, University of Sussex, Falmer, BN1 9QH, UK
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15
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Qin P, Grimm S, Duncan NW, Holland G, Guo JS, Fan Y, Weigand A, Baudewig J, Bajbouj M, Northoff G. Self-specific stimuli interact differently than non-self-specific stimuli with eyes-open versus eyes-closed spontaneous activity in auditory cortex. Front Hum Neurosci 2013; 7:437. [PMID: 23908625 PMCID: PMC3725474 DOI: 10.3389/fnhum.2013.00437] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 07/16/2013] [Indexed: 11/13/2022] Open
Abstract
Previous studies suggest that there may be a distinct relationship between spontaneous neural activity and subsequent or concurrent self-specific stimulus-induced activity. This study aims to test the impact of spontaneous activity as recorded in an eyes-open (EO) resting state as opposed to eyes-closed (EC) on self-specific versus non-self-specific auditory stimulus-induced activity in fMRI. In our first experiment we used self-specific stimuli comprised of the subject's own name and non-self-specific stimuli comprised of a friend's name and an unknown name, presented during EO versus EC baselines in a 3 name condition × 2 baseline design. In Experiment 2 we directly measured spontaneous activity in the absence of stimuli during EO versus EC to confirm a modulatory effect of the two baseline conditions in the regions found to show an interaction effect in Experiment 1. Spontaneous activity during EO was significantly higher than during EC in bilateral auditory cortex and non-self-specific names yielded stronger signal changes relative to EO baseline than to EC. In contrast, there was no difference in response to self-specific names relative to EO baseline than to EC despite the difference between spontaneous activity levels. These results support an impact of spontaneous activity on stimulus-induced activity, moreover an impact that depends on the high-level stimulus characteristic of self-specificity.
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Affiliation(s)
- Pengmin Qin
- Mind, Brain Imaging and Neuroethics Unit, University of Ottawa Institute of Mental Health Research (IMHR) , Ottawa, ON , Canada
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16
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Glutamate concentration in the medial prefrontal cortex predicts resting-state cortical-subcortical functional connectivity in humans. PLoS One 2013; 8:e60312. [PMID: 23573246 PMCID: PMC3616113 DOI: 10.1371/journal.pone.0060312] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Accepted: 02/25/2013] [Indexed: 12/13/2022] Open
Abstract
Communication between cortical and subcortical regions is integral to a wide range of psychological processes and has been implicated in a number of psychiatric conditions. Studies in animals have provided insight into the biochemical and connectivity processes underlying such communication. However, to date no experiments that link these factors in humans in vivo have been carried out. To investigate the role of glutamate in individual differences in communication between the cortex--specifically the medial prefrontal cortex (mPFC)--and subcortical regions in humans, a combination of resting-state fMRI, DTI and MRS was performed. The subcortical target regions were the nucleus accumbens (NAc), dorsomedial thalamus (DMT), and periaqueductal grey (PAG). It was found that functional connectivity between the mPFC and each of the NAc and DMT was positively correlated with mPFC glutamate concentrations, whilst functional connectivity between the mPFC and PAG was negatively correlated with glutamate concentration. The correlations involving mPFC glutamate and FC between the mPFC and each of the DMT and PAG were mirrored by correlations with structural connectivity, providing evidence that the glutamatergic relationship may, in part, be due to direct connectivity. These results are in agreement with existing results from animal studies and may have relevance for MDD and schizophrenia.
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Atlas construction for dynamic (4D) PET using diffeomorphic transformations. MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION : MICCAI ... INTERNATIONAL CONFERENCE ON MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION 2013; 16:35-42. [PMID: 24579121 DOI: 10.1007/978-3-642-40763-5_5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A novel dynamic (4D) PET to PET image registration procedure is proposed and applied to multiple PET scans acquired with the high resolution research tomograph (HRRT), the highest resolution human brain PET scanner available in the world. By extending the recent diffeomorphic log-demons (DLD) method and applying it to multiple dynamic [11C]raclopride scans from the HRRT, an important step towards construction of a PET atlas of unprecedented quality for [11C]raclopride imaging of the human brain has been achieved. Accounting for the temporal dimension in PET data improves registration accuracy when compared to registration of 3D to 3D time-averaged PET images. The DLD approach was chosen for its ease in providing both an intensity and shape template, through iterative sequential pair-wise registrations with fast convergence. The proposed method is applicable to any PET radiotracer, providing 4D atlases with useful applications in high accuracy PET data simulations and automated PET image analysis.
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