51
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Negative association between left prefrontal GABA concentration and BDNF serum concentration in young adults. Heliyon 2020; 6:e04025. [PMID: 32490241 PMCID: PMC7260440 DOI: 10.1016/j.heliyon.2020.e04025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 12/31/2019] [Accepted: 05/15/2020] [Indexed: 01/04/2023] Open
Abstract
Background The brain's major inhibitory neurotransmitter gamma-aminobutyric acid (GABA) and the brain-derived neurotrophic factor (BDNF) play important roles in several stress-related disorders. Magnetic resonance spectroscopy (MRS) allows for non-invasive quantification of GABA concentration in the brain. We investigated the relationship between GABA concentration in the left dorsolateral prefrontal cortex (DLPFC) and BDNF concentration in the serum in a community-based sample of young subjects. Methods For the GABA measurement a single voxel MR spectrum was assessed in the prefrontal lobe (25 × 40 × 30 mm) using the MEGA-PRESS method in 276 subjects. BDNF serum concentrations were assessed with an ELISA kit. For 147 subjects we had both MRS and BDNF serum data, and for 79 subjects we had genotype data on the BDNF rs6265 polymorphism. Depressive psychopathology was assessed using Beck's Depression Inventory (BDI), Montgomery-Asberg Depression Rating Scale (MADRS) and Structured Clinical Interviews for Diagnostic and Statistical Manual of Mental Disorders (SCID) for DSM-IV. Results GABA concentration in the left DLPFC was negatively associated with BDNF serum concentration (r = -.264, p = .001). This correlation remained significant if corrected for sex (r = -.264, p = .001). BDNF serum concentration was also positively associated with volumes and surface areas of the left prefrontal cortex (p = .048, p = .005). There were no significant associations or interaction with depressive psychopathology (BDI, MADRS, SCID) or rs6265. Conclusion The results of this study suggest that GABA, BDNF and prefrontal brain volumes are interrelated, but do not show a strong association to depressive psychopathology, possibly due to the mild forms of psychiatric conditions present in our community-based sample.
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Abstract
Background:Tics, defined as quick, rapid, sudden, recurrent, non-rhythmic motor movements or vocalizations are required components of Tourette Syndrome (TS) - a complex disorder characterized by the presence of fluctuating, chronic motor and vocal tics, and the presence of co-existing neuropsychological problems. Despite many advances, the underlying pathophysiology of tics/TS remains unknown.Objective:To address a variety of controversies surrounding the pathophysiology of TS. More specifically: 1) the configuration of circuits likely involved; 2) the role of inhibitory influences on motor control; 3) the classification of tics as either goal-directed or habitual behaviors; 4) the potential anatomical site of origin, e.g. cortex, striatum, thalamus, cerebellum, or other(s); and 5) the role of specific neurotransmitters (dopamine, glutamate, GABA, and others) as possible mechanisms (Abstract figure).Methods:Existing evidence from current clinical, basic science, and animal model studies are reviewed to provide: 1) an expanded understanding of individual components and the complex integration of the Cortico-Basal Ganglia-Thalamo-Cortical (CBGTC) circuit - the pathway involved with motor control; and 2) scientific data directly addressing each of the aforementioned controversies regarding pathways, inhibition, classification, anatomy, and neurotransmitters.Conclusion:Until a definitive pathophysiological mechanism is identified, one functional approach is to consider that a disruption anywhere within CBGTC circuitry, or a brain region inputting to the motor circuit, can lead to an aberrant message arriving at the primary motor cortex and enabling a tic. Pharmacologic modulation may be therapeutically beneficial, even though it might not be directed toward the primary abnormality.
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Affiliation(s)
- Harvey S. Singer
- Department of Neurology, Johns Hopkins Hospital, Baltimore, MD, United States
| | - Farhan Augustine
- Department of Neurology, Johns Hopkins Hospital, Baltimore, MD, United States
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53
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Hu H. Recent Advances of Bioresponsive Nano-Sized Contrast Agents for Ultra-High-Field Magnetic Resonance Imaging. Front Chem 2020; 8:203. [PMID: 32266217 PMCID: PMC7100386 DOI: 10.3389/fchem.2020.00203] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Accepted: 03/04/2020] [Indexed: 12/11/2022] Open
Abstract
The ultra-high-field magnetic resonance imaging (MRI) nowadays has been receiving enormous attention in both biomaterial research and clinical diagnosis. MRI contrast agents are generally comprising of T1-weighted and T2-weighted contrast agent types, where T1-weighted contrast agents show positive contrast enhancement with brighter images by decreasing the proton's longitudinal relaxation times and T2-weighted contrast agents show negative contrast enhancement with darker images by decreasing the proton's transverse relaxation times. To meet the incredible demand of MRI, ultra-high-field T2 MRI is gradually attracting the attention of research and medical needs owing to its high resolution and high accuracy for detection. It is anticipated that high field MRI contrast agents can achieve high performance in MRI imaging, where parameters of chemical composition, molecular structure and size of varied contrast agents show contrasted influence in each specific diagnostic test. This review firstly presents the recent advances of nanoparticle contrast agents for MRI. Moreover, multimodal molecular imaging with MRI for better monitoring is discussed during biological process. To fasten the process of developing better contrast agents, deep learning of artificial intelligent (AI) can be well-integrated into optimizing the crucial parameters of nanoparticle contrast agents and achieving high resolution MRI prior to the clinical applications. Finally, prospects and challenges are summarized.
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Affiliation(s)
- Hailong Hu
- School of Aeronautics and Astronautics, Central South University, Changsha, China
- Research Center in Intelligent Thermal Structures for Aerospace, Central South University, Changsha, China
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54
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Cirillo J, Mooney RA, Ackerley SJ, Barber PA, Borges VM, Clarkson AN, Mangold C, Ren A, Smith MC, Stinear CM, Byblow WD. Neurochemical balance and inhibition at the subacute stage after stroke. J Neurophysiol 2020; 123:1775-1790. [PMID: 32186435 DOI: 10.1152/jn.00561.2019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Stroke is a leading cause of death and disability worldwide with many people left with impaired motor function. Evidence from experimental animal models of stroke indicates that reducing motor cortex inhibition may facilitate neural plasticity and motor recovery. This study compared primary motor cortex (M1) inhibition measures over the first 12 wk after stroke with a cohort of age-similar healthy controls. The excitation-inhibition ratio and gamma-aminobutyric acid (GABA) neurotransmission within M1 were assessed using magnetic resonance spectroscopy and threshold hunting paired-pulse transcranial magnetic stimulation respectively. Upper limb impairment and function were assessed with the Fugl-Meyer Upper Extremity Scale and Action Research Arm Test. Patients with a functional corticospinal pathway had motor-evoked potentials on the paretic side and exhibited better recovery from upper limb impairment and recovery of function than patients without a functional corticospinal pathway. Compared with age-similar controls, the neurochemical balance in terms of the excitation-inhibition ratio was greater within contralesional M1 in patients with a functional corticospinal pathway. There was evidence for elevated long-interval inhibition in both ipsilesional and contralesional M1 compared with controls. Short-interval inhibition measures differed between the first and second phases, with evidence for elevation of the former only in ipsilesional M1 and no evidence of disinhibition for the latter. Overall, findings from transcranial magnetic stimulation indicate an upregulation of GABA-mediated tonic inhibition in M1 early after stroke. Therapeutic approaches that aim to normalize inhibitory tone during the subacute period warrant further investigation.NEW & NOTEWORTHY Magnetic resonance spectroscopy indicated higher excitation-inhibition ratios within motor cortex during subacute recovery than age-similar healthy controls. Measures obtained from adaptive threshold hunting paired-pulse transcranial magnetic stimulation indicated greater tonic inhibition in patients compared with controls. Therapeutic approaches that aim to normalize motor cortex inhibition during the subacute stage of recovery should be explored.
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Affiliation(s)
- John Cirillo
- Department of Exercise Sciences, University of Auckland, Auckland, New Zealand.,Centre for Brain Research, University of Auckland, Auckland, New Zealand
| | - Ronan A Mooney
- Department of Exercise Sciences, University of Auckland, Auckland, New Zealand.,Centre for Brain Research, University of Auckland, Auckland, New Zealand
| | - Suzanne J Ackerley
- Centre for Brain Research, University of Auckland, Auckland, New Zealand.,Department of Medicine, University of Auckland, Auckland, New Zealand
| | - P Alan Barber
- Centre for Brain Research, University of Auckland, Auckland, New Zealand.,Department of Medicine, University of Auckland, Auckland, New Zealand
| | - Victor M Borges
- Department of Exercise Sciences, University of Auckland, Auckland, New Zealand.,Centre for Brain Research, University of Auckland, Auckland, New Zealand
| | | | - Christine Mangold
- Centre for Brain Research, University of Auckland, Auckland, New Zealand
| | - April Ren
- Department of Exercise Sciences, University of Auckland, Auckland, New Zealand
| | - Marie-Claire Smith
- Centre for Brain Research, University of Auckland, Auckland, New Zealand.,Department of Medicine, University of Auckland, Auckland, New Zealand
| | - Cathy M Stinear
- Centre for Brain Research, University of Auckland, Auckland, New Zealand.,Department of Medicine, University of Auckland, Auckland, New Zealand
| | - Winston D Byblow
- Department of Exercise Sciences, University of Auckland, Auckland, New Zealand.,Centre for Brain Research, University of Auckland, Auckland, New Zealand
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55
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DeSouza DD, Stimpson KH, Baltusis L, Sacchet MD, Gu M, Hurd R, Wu H, Yeomans DC, Willliams N, Spiegel D. Association between Anterior Cingulate Neurochemical Concentration and Individual Differences in Hypnotizability. Cereb Cortex 2020; 30:3644-3654. [PMID: 32108220 DOI: 10.1093/cercor/bhz332] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Hypnosis is the oldest form of Western psychotherapy and a powerful evidence-based treatment for numerous disorders. Hypnotizability is variable between individuals; however, it is a stable trait throughout adulthood, suggesting that neurophysiological factors may underlie hypnotic responsiveness. One brain region of particular interest in functional neuroimaging studies of hypnotizability is the anterior cingulate cortex (ACC). Here, we examined the relationships between the neurochemicals, GABA, and glutamate, in the ACC and hypnotizability in healthy individuals. Participants underwent a magnetic resonance imaging (MRI) session, whereby T1-weighted anatomical and MEGA-PRESS spectroscopy scans were acquired. Voxel placement over the ACC was guided by a quantitative meta-analysis of functional neuroimaging studies of hypnosis. Hypnotizability was assessed using the Hypnotic Induction Profile (HIP), and self-report questionnaires to assess absorption (TAS), dissociation (DES), and negative affect were completed. ACC GABA concentration was positively associated with HIP scores such that the higher the GABA concentration, the more hypnotizable an individual. An exploratory analysis of questionnaire subscales revealed a negative relationship between glutamate and the absorption and imaginative involvement subscale of the DES. These results provide a putative neurobiological basis for individual differences in hypnotizability and can inform our understanding of treatment response to this growing psychotherapeutic tool.
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Affiliation(s)
- Danielle D DeSouza
- Department of Neurology and Neurological Sciences, Stanford University, Palo Alto, CA, USA
| | - Katy H Stimpson
- Department of Psychiatry and Behavioral Sciences, Stanford University, Palo Alto, CA, USA
| | - Laima Baltusis
- Center for Cognitive and Neurobiological Imaging, Stanford University, Palo Alto, CA, USA
| | - Matthew D Sacchet
- Center for Depression, Anxiety, and Stress Research, McLean Hospital, Harvard Medical School, Belmont MA, USA
| | - Meng Gu
- Radiology and Radiological Sciences, Stanford University, Palo Alto, CA, USA
| | - Ralph Hurd
- Radiology and Radiological Sciences, Stanford University, Palo Alto, CA, USA
| | - Hua Wu
- Center for Cognitive and Neurobiological Imaging, Stanford University, Palo Alto, CA, USA
| | - David C Yeomans
- Anesthesiology, Perioperative and Pain Medicine, Stanford University, Palo Alto, CA, USA
| | - Nolan Willliams
- Department of Psychiatry and Behavioral Sciences, Stanford University, Palo Alto, CA, USA
| | - David Spiegel
- Department of Psychiatry and Behavioral Sciences, Stanford University, Palo Alto, CA, USA
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56
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CRPS Is Not Associated with Altered Sensorimotor Cortex GABA or Glutamate. eNeuro 2020; 7:ENEURO.0389-19.2020. [PMID: 31980452 PMCID: PMC7029188 DOI: 10.1523/eneuro.0389-19.2020] [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] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 01/09/2020] [Accepted: 01/10/2020] [Indexed: 12/18/2022] Open
Abstract
Complex regional pain syndrome (CRPS) is a debilitating chronic pain disorder typically in the upper or lower limbs. While CRPS usually develops from a peripheral event, it is likely maintained by CNS changes. Indeed, CRPS is reported to be associated with sensorimotor cortex changes, or functional “reorganization,” as well as deficits such as poor tactile acuity. While the mechanisms underpinning cortical reorganization in CRPS are unknown, some have hypothesized that it involves disinhibition (i.e., a reduction in GABA activity). In this study, we addressed this hypothesis by using edited magnetic resonance spectroscopy to determine sensorimotor GABA and glutamate concentrations in 16 humans with CRPS and 30 matched control subjects and the relationship of these concentrations with tactile acuity. We found that individuals with upper limb CRPS displayed reduced tactile acuity in the painful hand, compared with the nonpainful hand and pain-free control subjects. Despite this acuity deficit, CRPS was not associated with altered GABA or glutamate concentrations within the sensorimotor cortex on either the side that represents the affected or unaffected hand. Furthermore, there was no significant relationship between sensorimotor GABA or glutamate concentrations and tactile acuity in CRPS subjects or control subjects. Although our sample was small, these data suggest that CRPS is not associated with altered total sensorimotor GABA or glutamate concentrations. While these results are at odds with the sensorimotor cortex disinhibition hypothesis, it is possible that GABAergic mechanisms other than total GABA concentration may contribute to such disinhibition.
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57
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Han M, Liao WY, Wu SM, Gong X, Bai C. Use of Streptococcus thermophilus for the in situ production of γ-aminobutyric acid-enriched fermented milk. J Dairy Sci 2020; 103:98-105. [DOI: 10.3168/jds.2019-16856] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 09/03/2019] [Indexed: 01/14/2023]
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58
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Cuypers K, Verstraelen S, Maes C, Hermans L, Hehl M, Heise KF, Chalavi S, Mikkelsen M, Edden R, Levin O, Sunaert S, Meesen R, Mantini D, Swinnen SP. Task-related measures of short-interval intracortical inhibition and GABA levels in healthy young and older adults: A multimodal TMS-MRS study. Neuroimage 2019; 208:116470. [PMID: 31863914 PMCID: PMC9652063 DOI: 10.1016/j.neuroimage.2019.116470] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 12/05/2019] [Accepted: 12/15/2019] [Indexed: 01/15/2023] Open
Abstract
Establishing the associations between magnetic resonance spectroscopy (MRS)-assessed gamma-aminobutyric acid (GABA) levels and transcranial magnetic stimulation (TMS)-derived ‘task-related’ modulations in GABAA receptor-mediated inhibition and how these associations change with advancing age is a topic of interest in the field of human neuroscience. In this study, we identified the relationship between GABA levels and task-related modulations in GABAA receptor-mediated inhibition in the dominant (left) and non-dominant (right) sensorimotor (SM) cortices. GABA levels were measured using edited MRS and task-related GABAA receptor-mediated inhibition was measured using a short-interval intracortical inhibition (SICI) TMS protocol during the preparation and premotor period of a choice reaction time (CRT) task in 25 young (aged 18–33 years) and 25 older (aged 60–74 years) adults. Our results demonstrated that GABA levels in both SM voxels were lower in older adults as compared to younger adults; and higher SM GABA levels in the dominant as compared to the non-dominant SM voxel pointed to a lateralization effect, irrespective of age group. Furthermore, older adults showed decreased GABAA receptor-mediated inhibition in the preparation phase of the CRT task within the dominant primary motor cortex (M1), as compared to young adults. Finally, results from an exploratory correlation analysis pointed towards positive relationships between MRS-assessed GABA levels and TMS-derived task-related SICI measures. However, after correction for multiple comparisons none of the correlations remained significant.
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Affiliation(s)
- K Cuypers
- Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium; REVAL Research Institute, Hasselt University, Agoralaan, Building A, 3590, Diepenbeek, Belgium.
| | - S Verstraelen
- REVAL Research Institute, Hasselt University, Agoralaan, Building A, 3590, Diepenbeek, Belgium
| | - C Maes
- Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium
| | - L Hermans
- Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium
| | - M Hehl
- Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium
| | - K-F Heise
- Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium
| | - S Chalavi
- Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium
| | - M Mikkelsen
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
| | - R Edden
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
| | - O Levin
- Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium
| | - S Sunaert
- Department of Imaging and Pathology, University Hospitals Leuven, Leuven, Belgium; Department of Radiology, University Hospitals Leuven, Gasthuisberg, UZ, Leuven, Belgium
| | - R Meesen
- Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium; REVAL Research Institute, Hasselt University, Agoralaan, Building A, 3590, Diepenbeek, Belgium
| | - D Mantini
- Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium; Brain Imaging and Neural Dynamics Research Group, IRCCS San Camillo Hospital, Venice, Italy
| | - S P Swinnen
- Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium; KU Leuven, Leuven Brain Institute (LBI), Leuven, Belgium
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59
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Gröhn H, Gillick BT, Tkáč I, Bednařík P, Mascali D, Deelchand DK, Michaeli S, Meekins GD, Leffler-McCabe MJ, MacKinnon CD, Eberly LE, Mangia S. Influence of Repetitive Transcranial Magnetic Stimulation on Human Neurochemistry and Functional Connectivity: A Pilot MRI/MRS Study at 7 T. Front Neurosci 2019; 13:1260. [PMID: 31827419 PMCID: PMC6890551 DOI: 10.3389/fnins.2019.01260] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 11/06/2019] [Indexed: 12/13/2022] Open
Abstract
Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation method commonly used in the disciplines of neuroscience, neurology, and neuropsychiatry to examine or modulate brain function. Low frequency rTMS (e.g., 1 Hz) is associated with a net suppression of cortical excitability, whereas higher frequencies (e.g., 5 Hz) purportedly increase excitability. Magnetic resonance spectroscopy (MRS) and resting-state functional MRI (rsfMRI) allow investigation of neurochemistry and functional connectivity, respectively, and can assess the influence of rTMS in these domains. This pilot study investigated the effects of rTMS on the primary motor cortex using pre and post MRS and rsfMRI assessments at 7 T. Seven right-handed males (age 27 ± 7 y.o.) underwent single-voxel MRS and rsfMRI before and about 30-min after rTMS was administered outside the scanner for 20-min over the primary motor cortex of the left (dominant) hemisphere. All participants received 1-Hz rTMS; one participant additionally received 5-Hz rTMS in a separate session. Concentrations of 17 neurochemicals were quantified in left and right motor cortices. Connectivity metrics included fractional amplitude of low-frequency fluctuations (fALFF) and regional homogeneity (ReHo) of both motor cortices, strength of related brain networks, and inter-hemispheric connectivity. The group-analysis revealed few trends (i.e., uncorrected for multiple comparisons), including a mean increase in the concentration of the inhibitory neurotransmitter γ-aminobutyric acid (GABA) after the inhibitory rTMS protocol as compared to baseline in the stimulated (left) motor cortex (+8%, p = 0.043), along with a slight increase of total creatine (+2%, p = 0.018), and decrease of aspartate (-18%, p = 0.016). Additionally, GABA tended to decrease in the contralateral hemisphere (-6%, p = 0.033). No other changes of metabolite concentrations were found. Whereas functional connectivity outcomes did not exhibit trends of significant changes induced by rTMS, the percent changes of few connectivity metrics in both hemispheres were negatively correlated with GABA changes in the contralateral hemisphere. While studies in larger cohorts are needed to confirm these preliminary findings, our results indicate the safety and feasibility of detecting changes in key metabolites associated with neurotransmission after a single 1-Hz rTMS session, establishing the construct for future exploration of the neurochemical, and connectivity mechanisms of cortical responses to neuromodulation.
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Affiliation(s)
- Heidi Gröhn
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States.,Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Bernadette T Gillick
- Department of Rehabilitation Medicine, University of Minnesota, Minneapolis, MN, United States
| | - Ivan Tkáč
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
| | - Petr Bednařík
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States.,Department of Biomedical Imaging and Image-guided Therapy, High Field MR Centre, Medical University of Vienna, Vienna, Austria
| | - Daniele Mascali
- Museo Storico della Fisica e Centro Studi e Ricerche "Enrico Fermi", Rome, Italy
| | - Dinesh K Deelchand
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
| | - Shalom Michaeli
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
| | - Gregg D Meekins
- Department of Neurology, University of Minnesota, Minneapolis, MN, United States
| | | | - Colum D MacKinnon
- Department of Neurology, University of Minnesota, Minneapolis, MN, United States
| | - Lynn E Eberly
- Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, MN, United States
| | - Silvia Mangia
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
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60
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Mooney RA, Ackerley SJ, Rajeswaran DK, Cirillo J, Barber PA, Stinear CM, Byblow WD. The Influence of Primary Motor Cortex Inhibition on Upper Limb Impairment and Function in Chronic Stroke: A Multimodal Study. Neurorehabil Neural Repair 2019; 33:130-140. [PMID: 30744527 DOI: 10.1177/1545968319826052] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
BACKGROUND Stroke is a leading cause of adult disability owing largely to motor impairment and loss of function. After stroke, there may be abnormalities in γ-aminobutyric acid (GABA)-mediated inhibitory function within primary motor cortex (M1), which may have implications for residual motor impairment and the potential for functional improvements at the chronic stage. OBJECTIVE To quantify GABA neurotransmission and concentration within ipsilesional and contralesional M1 and determine if they relate to upper limb impairment and function at the chronic stage of stroke. METHODS Twelve chronic stroke patients and 16 age-similar controls were recruited for the study. Upper limb impairment and function were assessed with the Fugl-Meyer Upper Extremity Scale and Action Research Arm Test. Threshold tracking paired-pulse transcranial magnetic stimulation protocols were used to examine short- and long-interval intracortical inhibition and late cortical disinhibition. Magnetic resonance spectroscopy was used to evaluate GABA concentration. RESULTS Short-interval intracortical inhibition was similar between patients and controls ( P = .10). Long-interval intracortical inhibition was greater in ipsilesional M1 compared with controls ( P < .001). Patients who did not exhibit late cortical disinhibition in ipsilesional M1 were those with greater upper limb impairment and worse function ( P = .002 and P = .017). GABA concentration was lower within ipsilesional ( P = .009) and contralesional ( P = .021) M1 compared with controls, resulting in an elevated excitation-inhibition ratio for patients. CONCLUSION These findings indicate that ipsilesional and contralesional M1 GABAergic inhibition are altered in this small cohort of chronic stroke patients. Further study is warranted to determine how M1 inhibitory networks might be targeted to improve motor function.
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Affiliation(s)
| | | | | | - John Cirillo
- 1 The University of Auckland, Auckland, New Zealand
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61
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Longitudinal assessment of 1H-MRS (GABA and Glx) and TMS measures of cortical inhibition and facilitation in the sensorimotor cortex. Exp Brain Res 2019; 237:3461-3474. [PMID: 31734787 DOI: 10.1007/s00221-019-05691-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Accepted: 11/09/2019] [Indexed: 01/05/2023]
Abstract
The purpose of the present study was to investigate the long-term stability of water-referenced GABA and Glx neurometabolite concentrations in the sensorimotor cortex using MRS and to assess the long-term stability of GABA- and glutamate-related intracortical excitability using transcranial magnetic stimulation (TMS). Healthy individuals underwent two sessions of MRS and TMS at a 3-month interval. A MEGA-PRESS sequence was used at 3 T to acquire MRS signals in the sensorimotor cortex. Metabolites were quantified by basis spectra fitting and metabolite concentrations were derived using unsuppressed water reference scans accounting for relaxation and partial volume effects. TMS was performed using published standards. After performing stability and reliability analyses for MRS and TMS, reliable change indexes were computed for all measures with a statistically significant test-retest correlation. No significant effect of time was found for GABA, Glx and TMS measures. There was an excellent ICC and a strong correlation across time for GABA and Glx. Analysis of TMS measure stability revealed an excellent ICC for rMT CSP and %MSO and a fair ICC for 2 ms SICI. There was no significant correlation between MRS and TMS measures at any time point. This study shows that MRS-GABA and MRS-Glx of the sensorimotor cortex have good stability over a 3-month period, with variability across time comparable to that reported in other brain areas. While resting motor threshold, %MSO and CSP were found to be stable and reliable, other TMS measures had greater variability and lesser reliability.
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62
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Pedapati EV, Mooney LN, Wu SW, Erickson CA, Sweeney JA, Shaffer RC, Horn PS, Wink LK, Gilbert DL. Motor cortex facilitation: a marker of attention deficit hyperactivity disorder co-occurrence in autism spectrum disorder. Transl Psychiatry 2019; 9:298. [PMID: 31723120 PMCID: PMC6853984 DOI: 10.1038/s41398-019-0614-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 09/23/2019] [Accepted: 10/15/2019] [Indexed: 01/06/2023] Open
Abstract
The neural correlates distinguishing youth with Autism Spectrum Disorder (ASD-) and ASD with co-occurring Attention Deficit Hyperactivity Disorder (ASD+) are poorly understood despite significant phenotypic and prognostic differences. Paired-pulse transcranial magnetic stimulation (TMS) measures, including intracortical facilitation (ICF), short interval cortical inhibition (SICI), and cortical silent period (CSP) were measured in an age matched cohort of youth with ASD- (n = 20), ASD + (n = 29), and controls (TDC) (n = 24). ASD- and ASD+ groups did not differ by IQ or social functioning; however, ASD+ had significantly higher inattention and hyperactivity ratings. ICF (higher ratio indicates greater facilitation) in ASD+ (Mean 1.0, SD 0.19) was less than ASD- (Mean 1.3, SD 0.36) or TDC (Mean 1.2, SD 0.24) (F2,68 = 6.5, p = 0.003; post-hoc tests, ASD+ vs either TDC or ASD-, p ≤ 0.05). No differences were found between groups for SICI or age corrected active/resting motor threshold (AMT/RMT). Across all ASD youth (ASD- and ASD+), ICF was inversely correlated with worse inattention (Conners-3 Inattention (r = -0.41; p < 0.01) and ADHDRS-IV Inattention percentile (r = -0.422, p < 0.01) scores. ICF remains intact in ASD- but is impaired in ASD+. Lack of ICF is associated with inattention and executive function across ASD. Taken with the present findings, ADHD may have a distinct electrophysiological "signature" in ASD youth. ICF may constitute an emerging biomarker to study the physiology of ADHD in ASD, which may align with disease prognosis or treatment response.
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Affiliation(s)
- Ernest V. Pedapati
- 0000 0000 9025 8099grid.239573.9Divisions of Child and Adolescent Psychiatry, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA ,0000 0000 9025 8099grid.239573.9Division of Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
| | - Lindsey N. Mooney
- 0000 0000 9025 8099grid.239573.9Division of Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA ,0000 0004 1936 9684grid.27860.3bDepartment of Psychology, University of California, Davis, CA USA
| | - Steve W. Wu
- 0000 0000 9025 8099grid.239573.9Divisions of Child and Adolescent Psychiatry, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
| | - Craig A. Erickson
- 0000 0000 9025 8099grid.239573.9Division of Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
| | - John A. Sweeney
- 0000 0001 2179 9593grid.24827.3bDepartment of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH USA
| | - Rebecca C. Shaffer
- 0000 0000 9025 8099grid.239573.9Developmental and Behavioral Pediatrics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
| | - Paul S. Horn
- 0000 0000 9025 8099grid.239573.9Divisions of Child and Adolescent Psychiatry, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA ,0000 0000 9025 8099grid.239573.9Divisions of Biostatistics and Epidemiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
| | - Logan K. Wink
- 0000 0000 9025 8099grid.239573.9Division of Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
| | - Donald L. Gilbert
- 0000 0000 9025 8099grid.239573.9Divisions of Child and Adolescent Psychiatry, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
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63
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van Nuland AJM, den Ouden HEM, Zach H, Dirkx MFM, van Asten JJA, Scheenen TWJ, Toni I, Cools R, Helmich RC. GABAergic changes in the thalamocortical circuit in Parkinson's disease. Hum Brain Mapp 2019; 41:1017-1029. [PMID: 31721369 PMCID: PMC7267977 DOI: 10.1002/hbm.24857] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 08/31/2019] [Accepted: 10/22/2019] [Indexed: 12/29/2022] Open
Abstract
Parkinson's disease is characterized by bradykinesia, rigidity, and tremor. These symptoms have been related to an increased gamma‐aminobutyric acid (GABA)ergic inhibitory drive from globus pallidus onto the thalamus. However, in vivo empirical evidence for the role of GABA in Parkinson's disease is limited. Some discrepancies in the literature may be explained by the presence or absence of tremor. Specifically, recent functional magnetic resonance imaging (fMRI) findings suggest that Parkinson's tremor is associated with reduced, dopamine‐dependent thalamic inhibition. Here, we tested the hypothesis that GABA in the thalamocortical motor circuit is increased in Parkinson's disease, and we explored differences between clinical phenotypes. We included 60 Parkinson patients with dopamine‐resistant tremor (n = 17), dopamine‐responsive tremor (n = 23), or no tremor (n = 20), and healthy controls (n = 22). Using magnetic resonance spectroscopy, we measured GABA‐to‐total‐creatine ratio in motor cortex, thalamus, and a control region (visual cortex) on two separate days (ON and OFF dopaminergic medication). GABA levels were unaltered by Parkinson's disease, clinical phenotype, or medication. However, motor cortex GABA levels were inversely correlated with disease severity, particularly rigidity and tremor, both ON and OFF medication. We conclude that cortical GABA plays a beneficial rather than a detrimental role in Parkinson's disease, and that GABA depletion may contribute to increased motor symptom expression.
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Affiliation(s)
- Annelies J M van Nuland
- Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Centre for Cognitive Neuroimaging, Nijmegen, The Netherlands
| | - Hanneke E M den Ouden
- Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Centre for Cognitive Neuroimaging, Nijmegen, The Netherlands
| | - Heidemarie Zach
- Radboud University Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Department of Neurology, Nijmegen, The Netherlands.,Medical University of Vienna, Department of Neurology, Vienna, Austria
| | - Michiel F M Dirkx
- Radboud University Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Department of Neurology, Nijmegen, The Netherlands
| | - Jack J A van Asten
- Radboud University Medical Centre, Department of Radiology and Nuclear Medicine, Nijmegen, The Netherlands
| | - Tom W J Scheenen
- Radboud University Medical Centre, Department of Radiology and Nuclear Medicine, Nijmegen, The Netherlands
| | - Ivan Toni
- Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Centre for Cognitive Neuroimaging, Nijmegen, The Netherlands
| | - Roshan Cools
- Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Centre for Cognitive Neuroimaging, Nijmegen, The Netherlands
| | - Rick C Helmich
- Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Centre for Cognitive Neuroimaging, Nijmegen, The Netherlands.,Radboud University Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Department of Neurology, Nijmegen, The Netherlands
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64
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Abstract
Tics are sudden, rapid, recurrent, nonrhythmic motor movements or vocalizations (phonic productions) that are commonly present in children and are required symptoms for the diagnosis of Tourette syndrome. Despite their frequency, the underlying pathophysiology of tics/Tourette syndrome remains unknown. In this review, we discuss a variety of controversies surrounding the pathophysiology of tics, including the following: Are tics voluntary or involuntary? What is the role of the premonitory urge? Are tics due to excess excitatory or deficient inhibition? Is it time to adopt the contemporary version of the cortico-basal ganglia-thalamocortical (CBGTC) circuit? and Do we know the primary abnormal neurotransmitter in Tourette syndrome? Data from convergent clinical and animal model studies support complex interactions among the various CBGTC sites and neurotransmitters. Advances are being made; however, numerous pathophysiologic questions persist.
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Affiliation(s)
- Harvey S Singer
- Department of Neurology, Johns Hopkins Hospital, Baltimore, MD, USA
| | - Farhan Augustine
- Department of Neurology, Johns Hopkins Hospital, Baltimore, MD, USA
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65
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Magalhães SC, Queiroz de Paiva JP, Kaelin-Lang A, Sterr A, Eckeli AL, Winkler AM, Fernandes do Prado G, Amaro E, Conforto AB. Short-interval intracortical inhibition is decreased in restless legs syndrome across a range of severity. Sleep Med 2019; 62:34-42. [PMID: 31539846 DOI: 10.1016/j.sleep.2019.03.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 03/10/2019] [Accepted: 03/12/2019] [Indexed: 01/18/2023]
Abstract
BACKGROUND Decreased short-interval intracortical inhibition (SICI) to transcranial magnetic stimulation (TMS) of the primary motor cortex was described in subjects with restless legs syndrome/Willis-Ekbom disease (RLS/WED). It remained to be determined whether the magnitude of SICI decrease would be similar across levels of RLS/WED severity. Moreover, it was unknown whether, in addition to decreases in SICI, changes in cortical thickness or area could be detected in subjects with RLS/WED compared to controls. The objective of this study was to compare SICI, cortical thickness, and cortical area in subjects with idiopathic mild to moderate RLS/WED, severe to very severe RLS/WED, and controls. METHODS The severity of RLS/WED was assessed by the International Restless Legs Syndrome Severity Scale (IRLSS). SICI and 3T magnetic resonance imaging (MRI) data of subjects with RLS/WED and controls were compared. A receiver operating characteristic curve for SICI was designed for discrimination of participants with RLS/WED from controls. Cortical thickness and area were assessed by automated surface-based analysis. RESULTS SICI was significantly reduced in patients with mild to moderate and severe to very severe RLS/WED, compared to controls (one-way analysis of variance: F = 9.62, p < 0.001). Receiver operating characteristic curve analysis predicted RLS/WED when SICI was above 35% (area under the curve = 0.79, 95% CI 0.67-0.91, p < 0.001). Analyses of the whole brain and of regions of interest did not reveal differences in gray matter thickness or area between controls and subjects with RLS/WED. CONCLUSION SICI is an accurate cortical biomarker that can support the diagnosis of RLS/WED even in subjects with mild symptoms, but cortical thickness and area were not useful for discriminating subjects with this condition from controls.
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Affiliation(s)
- Samir Câmara Magalhães
- Hospital Israelita Albert Einstein, São Paulo, SP, Brazil; Universidade de Fortaleza, Unifor, Fortaleza, CE, Brazil.
| | | | | | - Annette Sterr
- Department of Psychology, University of Surrey, Guildford, Surrey, UK
| | - Alan Luiz Eckeli
- Departamento de Neurociências e Ciências do Comportamento, Divisão de Neurologia, Hospital das Clínicas da Faculdade de Medicina da USP-Ribeirão Preto, Ribeirão Preto, SP, Brazil
| | | | | | - Edson Amaro
- Hospital Israelita Albert Einstein, São Paulo, SP, Brazil; Departamento de Radiologia, Hospital das Clínicas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Adriana Bastos Conforto
- Hospital Israelita Albert Einstein, São Paulo, SP, Brazil; Departamento de Neurologia, Hospital das Clínicas, Universidade de São Paulo, São Paulo, SP, Brazil
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66
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Hong D, van Asten JJA, Rankouhi SR, Thielen JW, Norris DG. Effect of linewidth on estimation of metabolic concentration when using water lineshape spectral model fitting for single voxel proton spectroscopy at 7 T. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 304:53-61. [PMID: 31102923 DOI: 10.1016/j.jmr.2019.05.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Revised: 04/14/2019] [Accepted: 05/08/2019] [Indexed: 06/09/2023]
Abstract
Good B0 field homogeneity is considered an essential requirement to obtain high-quality MRS data. Many commonly used spectral fitting methods assume that all metabolite signals have Lorentzian or Gaussian shapes. However, B0 inhomogeneity can both broaden the linewidth and modify the lineshape. In this study, it is hypothesized that a realistic metabolite fitting model, which accounts for B0 homogeneity on the basis of the water lineshape, will improve the accuracy of estimation of metabolite concentrations. In-vivo water suppressed/unsuppressed single voxel spectroscopy signals were acquired under three different B0 field homogeneity regimes. Individual realistic basis sets were created for each acquisition. Frequency-domain spectral fitting with LCModel was used to quantify the metabolite concentrations with fitting uncertainties given in terms of the Cramer-Rao lower bound. The quantification results obtained using the water lineshape basis set yielded similar concentrations independent of linewidth and showed a larger fitting error as the linewidth increased. The conventional approach, however quantifies metabolite concentrations with greater variations despite showing a supposedly improved fitting quality. The water lineshape basis set achieved single voxel spectroscopy accuracy that is less sensitive to the linewidth compared to the conventional spectral fitting method for the range of linewidths used in this study, but the precision deteriorated with worsening B0 field inhomogeneity. The beneficial effect was ascribed to a reduction in the number of degrees of freedom when using the water lineshape to generate the basis set.
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Affiliation(s)
- Donghyun Hong
- Erwin L. Hahn Institute for Magnetic Resonance Imaging, University of Duisburg-Essen, Essen, Germany.
| | - Jack J A van Asten
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | | | - Jan-Willem Thielen
- Erwin L. Hahn Institute for Magnetic Resonance Imaging, University of Duisburg-Essen, Essen, Germany; Department for Psychiatry and Psychotherapy, Faculty of Medicine, University of Duisburg-Essen, Essen, Germany
| | - David G Norris
- Erwin L. Hahn Institute for Magnetic Resonance Imaging, University of Duisburg-Essen, Essen, Germany; Donders Institute for Brain, Cognition, and Behavior, Radboud University, Nijmegen, Netherlands
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Rae CL, Critchley HD, Seth AK. A Bayesian Account of the Sensory-Motor Interactions Underlying Symptoms of Tourette Syndrome. Front Psychiatry 2019; 10:29. [PMID: 30890965 PMCID: PMC6412155 DOI: 10.3389/fpsyt.2019.00029] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 01/17/2019] [Indexed: 11/17/2022] Open
Abstract
Tourette syndrome is a hyperkinetic movement disorder. Characteristic features include tics, recurrent movements that are experienced as compulsive and "unwilled"; uncomfortable premonitory sensations that resolve through tic release; and often, the ability to suppress tics temporarily. We demonstrate how these symptoms and features can be understood in terms of aberrant predictive (Bayesian) processing in hierarchical neural systems, explaining specifically: why tics arise, their "unvoluntary" nature, how premonitory sensations emerge, and why tic suppression works-sometimes. In our model, premonitory sensations and tics are generated through over-precise priors for sensation and action within somatomotor regions of the striatum. Abnormally high precision of priors arises through the dysfunctional synaptic integration of cortical inputs. These priors for sensation and action are projected into primary sensory and motor areas, triggering premonitory sensations and tics, which in turn elicit prediction errors for unexpected feelings and movements. We propose experimental paradigms to validate this Bayesian account of tics. Our model integrates behavioural, neuroimaging, and computational approaches to provide mechanistic insight into the pathophysiological basis of Tourette syndrome.
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Affiliation(s)
- Charlotte L. Rae
- Sackler Centre for Consciousness Science, University of Sussex, Brighton, United Kingdom
- Department of Neuroscience, Brighton and Sussex Medical School, Brighton, United Kingdom
| | - Hugo D. Critchley
- Sackler Centre for Consciousness Science, University of Sussex, Brighton, United Kingdom
- Department of Neuroscience, Brighton and Sussex Medical School, Brighton, United Kingdom
- Sussex Partnership NHS Foundation Trust, Brighton, United Kingdom
| | - Anil K. Seth
- Sackler Centre for Consciousness Science, University of Sussex, Brighton, United Kingdom
- School of Engineering and Informatics, University of Sussex, Brighton, United Kingdom
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68
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Proton Magnetic Resonance Spectroscopy of the motor cortex reveals long term GABA change following anodal Transcranial Direct Current Stimulation. Sci Rep 2019; 9:2807. [PMID: 30808895 PMCID: PMC6391486 DOI: 10.1038/s41598-019-39262-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 01/15/2019] [Indexed: 12/22/2022] Open
Abstract
Anodal transcranial direct current stimulation (tDCS) over the primary motor cortex (M1) has been reported to increase the firing rates of neurons and to modulate the gamma-aminobutyric acid (GABA) concentration. To date, knowledge about the nature and duration of these tDCS induced effects is incomplete. We aimed to investigate long-term effects of anodal tDCS over M1 on GABA dynamics in humans. Repeated magnetic resonance spectroscopy (MRS) was employed to measure relative GABA concentration in M1 for approximately 64 minutes after stimulation. The study was performed on 32 healthy subjects. Either anodal or sham tDCS were applied for 10 minutes with the active electrode over the left M1 and the reference electrode over the right supra-orbital region. Pre and post-tDCS MRS scans were performed to acquire GABA-edited spectra using 3 T Prisma Siemens scanner. GABA signals showed no change over time in the sham tDCS group, whereas anodal tDCS resulted in a significant early decrease within 25 minutes after tDCS and then significant late decrease after 66 minutes which continued until the last test measurements. The late changes in GABA concentration might be related to long-term plasticity mechanism. These results contribute to a better understanding of the neurochemical mechanism underlying long-term cortical plasticity following anodal tDCS.
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69
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Prolonged cortical silent period is related to poor fitness and fatigue, but not tumor necrosis factor, in Multiple Sclerosis. Clin Neurophysiol 2019; 130:474-483. [PMID: 30771724 DOI: 10.1016/j.clinph.2018.12.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 12/08/2018] [Accepted: 12/21/2018] [Indexed: 11/23/2022]
Abstract
OBJECTIVE Poor fitness among people with Multiple Sclerosis (MS) aggravates disease symptoms. Whether low fitness levels accompany brain functioning changes is unknown. METHODS MS patients (n = 82) completed a graded maximal exercise test, blood was drawn, and transcranial magnetic stimulation determined resting and active motor thresholds, motor evoked potential latency, and cortical silent period (CSP). RESULTS Sixty-two percent of participants had fitness levels ranked below 10th percentile. Fitness was not associated with disability measured using the Expanded Disability Status Scale (EDSS). Regression analyses revealed that, cardiorespiratory fitness, when controlling for disease demographics, contributed 23.7% (p < 0.001) to the model explaining variance in CSP. Regression analysis using cardiorespiratory fitness and CSP as predictors showed that CSP alone explained 19.9% of variance in subjective fatigue (p = 0.002). Tumor necrosis factor was not associated with any variable. CONCLUSION Low fitness was associated with longer CSP in MS. Longer CSP was, in turn, related to greater MS fatigue. SIGNIFICANCE MS patients had extremely low levels of cardiorespiratory fitness. Poor fitness predicted longer CSP, a marker of greater intracortical inhibition, which was linked to MS fatigue. Future research should examine whether aerobic training could shorten CSP and potentially lessen inhibition of cortical networks.
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Abstract
Adolescent depression is a substantial global public health problem that contributes to academic failure, occupational impairment, deficits in social functioning, substance use disorders, teen pregnancy, and completed suicide. Existing treatment options often have suboptimal results and uncertain safety profiles. Transcranial magnetic stimulation may be a promising, brain-based intervention for adolescents with depression. Existing work has methodological weaknesses, and larger, neurodevelopmentally informed studies are urgently needed. Treatment with transcranial magnetic stimulation may modulate cortical GABAergic and glutamatergic imbalances. Future study will inform dosing approaches for TMS based on GABAergic and glutamatergic biomarkers.
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Affiliation(s)
- Paul E Croarkin
- Child and Adolescent Psychiatry, Mayo Clinic College of Medicine and Science, 200 First Street Southwest, Rochester, MN 55905, USA.
| | - Frank P MacMaster
- Strategic Clinical Network for Addictions and Mental Health, University of Calgary, Alberta Children's Hospital, Office Number: B4-511, 2500 University Dr. NWCalgary, Alberta, T2N 1N4, Canada
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Sun Y, Seneviratne U, Perucca P, Chen Z, Kee MT, O'Brien TJ, D'Souza W, Kwan P. Generalized polyspike train: An EEG biomarker of drug-resistant idiopathic generalized epilepsy. Neurology 2018; 91:e1822-e1830. [PMID: 30315071 DOI: 10.1212/wnl.0000000000006472] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Accepted: 08/01/2018] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To identify clinical and EEG biomarkers of drug resistance in adults with idiopathic generalized epilepsy. METHODS We conducted a case-control study consisting of a discovery cohort and a replication cohort independently assessed at 2 different centers. In each center, patients with the idiopathic generalized epilepsy phenotype and generalized spike-wave discharges on EEG were classified as drug-resistant or drug-responsive. EEG changes were classified into predefined patterns and compared between the 2 groups in the discovery cohort. Factors associated with drug resistance in multivariable analysis were tested in the replication cohort. RESULTS The discovery cohort included 85 patients (29% drug-resistant and 71% drug-responsive). Their median age at assessment was 32 years and 50.6% were female. Multivariable analysis showed that higher number of seizure types ever experienced (3 vs 1: odds ratio [OR] = 31.1, 95% confidence interval [CI]: 4.5-214, p < 0.001; 3 vs 2: OR = 14.6, 95% CI: 2.3-93.1, p = 0.004) and generalized polyspike train (burst of generalized rhythmic spikes lasting less than 1 second) during sleep were associated with drug resistance (OR = 10.8, 95% CI: 2.4-49.4, p = 0.002). When these factors were tested in the replication cohort of 80 patients (27.5% drug-resistant and 72.5% drug-responsive; 71.3% female; median age 27.5 years), the proportion of patients with generalized polyspike train during sleep was also higher in the drug-resistant group (OR = 4.0, 95% CI: 1.35-11.8, p = 0.012). CONCLUSION Generalized polyspike train during sleep may be an EEG biomarker for drug resistance in adults with idiopathic generalized epilepsy.
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Affiliation(s)
- Yanping Sun
- From the Department of Neurology (Y.S.), The Affiliated Hospital of Qingdao University, Qingdao, China; Department of Neurology (Y.S.), Xuanwu Hospital, Capital Medical University, Beijing, China; Departments of Neurology (Y.S., P.P., M.K.T., T.J.O., P.K.) and Medicine (P.P., Z.C., T.J.O., P.K.), The Royal Melbourne Hospital, The University of Melbourne, Victoria; Department of Medicine (U.S., W.D.), St. Vincent's Hospital Melbourne, The University of Melbourne, Victoria; Department of Medicine, The School of Clinical Sciences at Monash Health (U.S.), and Departments of Neuroscience, The Central Clinical School (P.P., T.J.O., P.K.), Monash University, Victoria; and Department of Neurology (P.P., T.J.O., P.K.), The Alfred Hospital, Victoria, Australia
| | - Udaya Seneviratne
- From the Department of Neurology (Y.S.), The Affiliated Hospital of Qingdao University, Qingdao, China; Department of Neurology (Y.S.), Xuanwu Hospital, Capital Medical University, Beijing, China; Departments of Neurology (Y.S., P.P., M.K.T., T.J.O., P.K.) and Medicine (P.P., Z.C., T.J.O., P.K.), The Royal Melbourne Hospital, The University of Melbourne, Victoria; Department of Medicine (U.S., W.D.), St. Vincent's Hospital Melbourne, The University of Melbourne, Victoria; Department of Medicine, The School of Clinical Sciences at Monash Health (U.S.), and Departments of Neuroscience, The Central Clinical School (P.P., T.J.O., P.K.), Monash University, Victoria; and Department of Neurology (P.P., T.J.O., P.K.), The Alfred Hospital, Victoria, Australia
| | - Piero Perucca
- From the Department of Neurology (Y.S.), The Affiliated Hospital of Qingdao University, Qingdao, China; Department of Neurology (Y.S.), Xuanwu Hospital, Capital Medical University, Beijing, China; Departments of Neurology (Y.S., P.P., M.K.T., T.J.O., P.K.) and Medicine (P.P., Z.C., T.J.O., P.K.), The Royal Melbourne Hospital, The University of Melbourne, Victoria; Department of Medicine (U.S., W.D.), St. Vincent's Hospital Melbourne, The University of Melbourne, Victoria; Department of Medicine, The School of Clinical Sciences at Monash Health (U.S.), and Departments of Neuroscience, The Central Clinical School (P.P., T.J.O., P.K.), Monash University, Victoria; and Department of Neurology (P.P., T.J.O., P.K.), The Alfred Hospital, Victoria, Australia
| | - Zhibin Chen
- From the Department of Neurology (Y.S.), The Affiliated Hospital of Qingdao University, Qingdao, China; Department of Neurology (Y.S.), Xuanwu Hospital, Capital Medical University, Beijing, China; Departments of Neurology (Y.S., P.P., M.K.T., T.J.O., P.K.) and Medicine (P.P., Z.C., T.J.O., P.K.), The Royal Melbourne Hospital, The University of Melbourne, Victoria; Department of Medicine (U.S., W.D.), St. Vincent's Hospital Melbourne, The University of Melbourne, Victoria; Department of Medicine, The School of Clinical Sciences at Monash Health (U.S.), and Departments of Neuroscience, The Central Clinical School (P.P., T.J.O., P.K.), Monash University, Victoria; and Department of Neurology (P.P., T.J.O., P.K.), The Alfred Hospital, Victoria, Australia
| | - Meng Tan Kee
- From the Department of Neurology (Y.S.), The Affiliated Hospital of Qingdao University, Qingdao, China; Department of Neurology (Y.S.), Xuanwu Hospital, Capital Medical University, Beijing, China; Departments of Neurology (Y.S., P.P., M.K.T., T.J.O., P.K.) and Medicine (P.P., Z.C., T.J.O., P.K.), The Royal Melbourne Hospital, The University of Melbourne, Victoria; Department of Medicine (U.S., W.D.), St. Vincent's Hospital Melbourne, The University of Melbourne, Victoria; Department of Medicine, The School of Clinical Sciences at Monash Health (U.S.), and Departments of Neuroscience, The Central Clinical School (P.P., T.J.O., P.K.), Monash University, Victoria; and Department of Neurology (P.P., T.J.O., P.K.), The Alfred Hospital, Victoria, Australia
| | - Terence J O'Brien
- From the Department of Neurology (Y.S.), The Affiliated Hospital of Qingdao University, Qingdao, China; Department of Neurology (Y.S.), Xuanwu Hospital, Capital Medical University, Beijing, China; Departments of Neurology (Y.S., P.P., M.K.T., T.J.O., P.K.) and Medicine (P.P., Z.C., T.J.O., P.K.), The Royal Melbourne Hospital, The University of Melbourne, Victoria; Department of Medicine (U.S., W.D.), St. Vincent's Hospital Melbourne, The University of Melbourne, Victoria; Department of Medicine, The School of Clinical Sciences at Monash Health (U.S.), and Departments of Neuroscience, The Central Clinical School (P.P., T.J.O., P.K.), Monash University, Victoria; and Department of Neurology (P.P., T.J.O., P.K.), The Alfred Hospital, Victoria, Australia.
| | - Wendyl D'Souza
- From the Department of Neurology (Y.S.), The Affiliated Hospital of Qingdao University, Qingdao, China; Department of Neurology (Y.S.), Xuanwu Hospital, Capital Medical University, Beijing, China; Departments of Neurology (Y.S., P.P., M.K.T., T.J.O., P.K.) and Medicine (P.P., Z.C., T.J.O., P.K.), The Royal Melbourne Hospital, The University of Melbourne, Victoria; Department of Medicine (U.S., W.D.), St. Vincent's Hospital Melbourne, The University of Melbourne, Victoria; Department of Medicine, The School of Clinical Sciences at Monash Health (U.S.), and Departments of Neuroscience, The Central Clinical School (P.P., T.J.O., P.K.), Monash University, Victoria; and Department of Neurology (P.P., T.J.O., P.K.), The Alfred Hospital, Victoria, Australia
| | - Patrick Kwan
- From the Department of Neurology (Y.S.), The Affiliated Hospital of Qingdao University, Qingdao, China; Department of Neurology (Y.S.), Xuanwu Hospital, Capital Medical University, Beijing, China; Departments of Neurology (Y.S., P.P., M.K.T., T.J.O., P.K.) and Medicine (P.P., Z.C., T.J.O., P.K.), The Royal Melbourne Hospital, The University of Melbourne, Victoria; Department of Medicine (U.S., W.D.), St. Vincent's Hospital Melbourne, The University of Melbourne, Victoria; Department of Medicine, The School of Clinical Sciences at Monash Health (U.S.), and Departments of Neuroscience, The Central Clinical School (P.P., T.J.O., P.K.), Monash University, Victoria; and Department of Neurology (P.P., T.J.O., P.K.), The Alfred Hospital, Victoria, Australia.
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Kolasinski J, Hinson EL, Divanbeighi Zand AP, Rizov A, Emir UE, Stagg CJ. The dynamics of cortical GABA in human motor learning. J Physiol 2018; 597:271-282. [PMID: 30300446 PMCID: PMC6312422 DOI: 10.1113/jp276626] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 10/04/2018] [Indexed: 12/20/2022] Open
Abstract
Key points The ability to learn new motor skills is supported by plasticity in the structural and functional organisation of the primary motor cortex in the human brain. Changes inhibitory to signalling by GABA are thought to be crucial in inducing motor cortex plasticity. This study used magnetic resonance spectroscopy (MRS) to quantify the concentration of GABA in human motor cortex during a period of motor learning, as well as during a period of movement and a period at rest. We report evidence for a reduction in the MRS‐measured concentration of GABA specific to learning. Further, the GABA concentration early in the learning task was strongly correlated with the magnitude of subsequent learning: higher GABA concentrations were associated with poorer learning. The results provide initial insight into the neurochemical correlates of cortical plasticity associated with motor learning, specifically relevant in therapeutic efforts to induce cortical plasticity during recovery from stroke.
Abstract The ability to learn novel motor skills is a central part of our daily lives and can provide a model for rehabilitation after a stroke. However, there are still fundamental gaps in our understanding of the physiological mechanisms that underpin human motor plasticity. The acquisition of new motor skills is dependent on changes in local circuitry within the primary motor cortex (M1). This reorganisation has been hypothesised to be facilitated by a decrease in local inhibition via modulation of the neurotransmitter GABA, but this link has not been conclusively demonstrated in humans. Here, we used 7 T magnetic resonance spectroscopy to investigate the dynamics of GABA concentrations in human M1 during the learning of an explicit, serial reaction time task. We observed a significant reduction in GABA concentration during motor learning that was not seen in an equivalent motor task lacking a learnable sequence, nor during a passive resting task of the same duration. No change in glutamate was observed in any group. Furthermore, M1 GABA measured early in task performance was strongly correlated with the degree of subsequent learning, such that greater inhibition was associated with poorer subsequent learning. This result suggests that higher levels of cortical inhibition may present a barrier that must be surmounted in order to achieve an increase in M1 excitability, and hence encoding of a new motor skill. These results provide strong support for the mechanistic role of GABAergic inhibition in motor plasticity, raising questions regarding the link between population variability in motor learning and GABA metabolism in the brain. The ability to learn new motor skills is supported by plasticity in the structural and functional organisation of the primary motor cortex in the human brain. Changes inhibitory to signalling by GABA are thought to be crucial in inducing motor cortex plasticity. This study used magnetic resonance spectroscopy (MRS) to quantify the concentration of GABA in human motor cortex during a period of motor learning, as well as during a period of movement and a period at rest. We report evidence for a reduction in the MRS‐measured concentration of GABA specific to learning. Further, the GABA concentration early in the learning task was strongly correlated with the magnitude of subsequent learning: higher GABA concentrations were associated with poorer learning. The results provide initial insight into the neurochemical correlates of cortical plasticity associated with motor learning, specifically relevant in therapeutic efforts to induce cortical plasticity during recovery from stroke.
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Affiliation(s)
- James Kolasinski
- Wellcome Centre for Integrative Neuroimaging, Oxford Centre for fMRI of the Brain, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 7DU, UK.,Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Maindy Road, Cardiff, CF24 4HQ, UK
| | - Emily L Hinson
- Wellcome Centre for Integrative Neuroimaging, Oxford Centre for fMRI of the Brain, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 7DU, UK.,Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford, OX3 7JX, UK
| | - Amir P Divanbeighi Zand
- Wellcome Centre for Integrative Neuroimaging, Oxford Centre for fMRI of the Brain, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 7DU, UK
| | - Assen Rizov
- Wellcome Centre for Integrative Neuroimaging, Oxford Centre for fMRI of the Brain, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 7DU, UK
| | - Uzay E Emir
- Wellcome Centre for Integrative Neuroimaging, Oxford Centre for fMRI of the Brain, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 7DU, UK.,Purdue University School of Health Sciences, 550 Stadium Mall Drive, West Lafayette, IN, 47907, USA
| | - Charlotte J Stagg
- Wellcome Centre for Integrative Neuroimaging, Oxford Centre for fMRI of the Brain, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 7DU, UK.,Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford, OX3 7JX, UK
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73
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Reuveni I, Nugent AC, Gill J, Vythilingam M, Carlson PJ, Lerner A, Neumeister A, Charney DS, Drevets WC, Bonne O. Altered cerebral benzodiazepine receptor binding in post-traumatic stress disorder. Transl Psychiatry 2018; 8:206. [PMID: 30287828 PMCID: PMC6172250 DOI: 10.1038/s41398-018-0257-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 07/19/2018] [Accepted: 08/17/2018] [Indexed: 12/27/2022] Open
Abstract
Agonists of the γ-aminobutyric acid (GABA) type A benzodiazepine (BZD) receptor exert anxiolytic effects in anxiety disorders, raising the possibility that altered GABA-ergic function may play a role in the pathophysiology of anxiety disorders, such as post-traumatic stress disorder (PTSD). However, few neuroimaging studies have assessed the function or binding potential of the central GABAA BZD receptor system in PTSD. Therefore, our aim was to compare the BZD receptor binding potential between PTSD patients and healthy controls. Twelve medication-free participants with a current diagnosis of PTSD and 15 matched healthy controls underwent positron emission tomography (PET) imaging using [11C] flumazenil. Structural magnetic resonance imaging (MRI) scans were obtained and co-registered to the PET images to permit co-location of neuroanatomical structures in the lower resolution PET image data. Compared to healthy controls, PTSD patients exhibited increased BZD binding in the caudal anterior cingulate cortex and precuneus (p's < 0.05). Severity of PTSD symptoms positively correlated with BZD binding in the left mid- and anterior insular cortices. This study extends previous findings by suggesting that central BZD receptor system involvement in PTSD includes portions of the default mode and salience networks, along with insular regions that support interoception and autonomic arousal.
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Affiliation(s)
- Inbal Reuveni
- 0000 0001 2221 2926grid.17788.31Department of Psychiatry, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| | - Allison C. Nugent
- 0000 0004 0464 0574grid.416868.5Experimental Therapeutics and Pathophysiology Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD USA
| | - Jessica Gill
- 0000 0001 2297 5165grid.94365.3dCenter for Neuroscience and Regenerative Medicine (CNRM), National Institutes of Health, Bethesda, MD USA
| | - Meena Vythilingam
- Deployment Health Clinical Center, Defense Centers of Excellence for Psychological Health and Traumatic Brain Injury, Silver Spring, MD USA
| | - Paul J. Carlson
- 0000 0001 2193 0096grid.223827.eDepartment of Psychiatry, University of Utah School of Medicine, Salt Lake City, UT USA
| | - Alicja Lerner
- 0000 0001 2243 3366grid.417587.8Controlled Substance Staff, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, MD USA
| | - Alexander Neumeister
- 0000 0001 2182 2255grid.28046.38Institute of Mental Health Research (IMHR), University of Ottawa, Ottawa, ON Canada
| | - Dennis S. Charney
- 0000 0001 0670 2351grid.59734.3cMood and Anxiety Disorders Program, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY USA
| | - Wayne C. Drevets
- grid.417429.dJanssen Research and Development, LLC of Johnson & Johnson Inc., Titusville, NJ USA
| | - Omer Bonne
- Department of Psychiatry, Hadassah Hebrew University Medical Center, Jerusalem, Israel.
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74
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Reduced GABAergic cortical inhibition in aging and depression. Neuropsychopharmacology 2018; 43:2277-2284. [PMID: 29849055 PMCID: PMC6135847 DOI: 10.1038/s41386-018-0093-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 01/31/2018] [Accepted: 05/08/2018] [Indexed: 12/29/2022]
Abstract
The neurobiology underlying depression in older adults is less extensively evaluated than in younger adults, despite the putative influence of aging on depression neuropathology. Studies using transcranial magnetic stimulation (TMS), a neurophysiological tool capable of probing inhibitory and excitatory cortical neurotransmission, have identified dysfunctional GABAergic inhibitory activity in younger adults with depression. However, GABAergic and glutamatergic cortical neurotransmission have not yet been studied in late-life depression (LLD). Here, we used single- and paired-pulse TMS to measure cortical inhibition and excitation in 92 LLD patients and 41 age-matched healthy controls. To differentiate the influence of age and depression, we also compared these TMS indices to those of 30 younger depressed adults and 30 age- and sex-matched younger healthy adults. LLD patients, older healthy adults, and younger depressed adults demonstrated significantly lower GABAA receptor-mediated cortical inhibition than younger healthy controls. By contrast, no significant differences in cortical inhibition were observed between older adults with and without depression. No significant differences in GABAB receptor-mediated inhibition or cortical excitation were found between the groups. Altogether, these findings suggest that reduced cortical inhibition may be associated with both advancing age and depression, which (i) supports the model of depression as a disease of accelerated aging, and (ii) prompts future investigation into diminished GABAergic neurotransmission in late-life as a biological predisposing factor to the development of depression. Given that cortical neurophysiology was similar in depressed and healthy older adults, future prospective studies need to establish the relative influence of age and depression on cortical inhibition deficits.
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75
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Firbank MJ, Parikh J, Murphy N, Killen A, Allan CL, Collerton D, Blamire AM, Taylor JP. Reduced occipital GABA in Parkinson disease with visual hallucinations. Neurology 2018; 91:e675-e685. [PMID: 30021920 PMCID: PMC6105043 DOI: 10.1212/wnl.0000000000006007] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 05/23/2018] [Indexed: 02/06/2023] Open
Abstract
Objective To investigate the relationship between visual hallucinations in Parkinson disease (PD) and levels of γ-aminobutyric acid (GABA) in the primary visual cortex. Methods We utilized magnetic resonance spectroscopy to investigate occipital GABA levels in 36 participants with PD, 19 with and 17 without complex visual hallucinations, together with 20 healthy controls without hallucinations. In addition, we acquired T1-weighted MRI, whole-brain fMRI during a visual task, and diffusion tensor imaging. Results We found lower GABA+/creatine in PD with visual hallucinations (0.091 ± 0.010) vs those without (0.101 ± 0.010) and controls (0.099 ± 0.010) (F2,49 = 4.5; p = 0.016). Reduced gray matter in the hallucinations group was also observed in the anterior temporal lobe. Although there were widespread reductions in white matter integrity in the visual hallucinations group, this was no longer significant after controlling for cognitive function. Conclusions The data suggest that reduced levels of GABA are associated with visual hallucinations in PD and implicate changes to the ventral visual stream in the genesis of visual hallucinations. Modulation of visual cortical excitability through, for example, pharmacologic intervention, may be a promising treatment avenue to explore.
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Affiliation(s)
- Michael J Firbank
- From the Institute of Neuroscience (M.J.F., A.K., C.L.A., D.C., J.-P.T.), Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne; and Newcastle Magnetic Resonance Centre (J.P., A.M.B.), Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK; and Baylor College of Medicine (N.M.), Houston, TX.
| | - Jehill Parikh
- From the Institute of Neuroscience (M.J.F., A.K., C.L.A., D.C., J.-P.T.), Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne; and Newcastle Magnetic Resonance Centre (J.P., A.M.B.), Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK; and Baylor College of Medicine (N.M.), Houston, TX
| | - Nicholas Murphy
- From the Institute of Neuroscience (M.J.F., A.K., C.L.A., D.C., J.-P.T.), Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne; and Newcastle Magnetic Resonance Centre (J.P., A.M.B.), Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK; and Baylor College of Medicine (N.M.), Houston, TX
| | - Alison Killen
- From the Institute of Neuroscience (M.J.F., A.K., C.L.A., D.C., J.-P.T.), Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne; and Newcastle Magnetic Resonance Centre (J.P., A.M.B.), Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK; and Baylor College of Medicine (N.M.), Houston, TX
| | - Charlotte L Allan
- From the Institute of Neuroscience (M.J.F., A.K., C.L.A., D.C., J.-P.T.), Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne; and Newcastle Magnetic Resonance Centre (J.P., A.M.B.), Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK; and Baylor College of Medicine (N.M.), Houston, TX
| | - Daniel Collerton
- From the Institute of Neuroscience (M.J.F., A.K., C.L.A., D.C., J.-P.T.), Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne; and Newcastle Magnetic Resonance Centre (J.P., A.M.B.), Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK; and Baylor College of Medicine (N.M.), Houston, TX
| | - Andrew M Blamire
- From the Institute of Neuroscience (M.J.F., A.K., C.L.A., D.C., J.-P.T.), Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne; and Newcastle Magnetic Resonance Centre (J.P., A.M.B.), Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK; and Baylor College of Medicine (N.M.), Houston, TX
| | - John-Paul Taylor
- From the Institute of Neuroscience (M.J.F., A.K., C.L.A., D.C., J.-P.T.), Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne; and Newcastle Magnetic Resonance Centre (J.P., A.M.B.), Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK; and Baylor College of Medicine (N.M.), Houston, TX
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76
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Maes C, Hermans L, Pauwels L, Chalavi S, Leunissen I, Levin O, Cuypers K, Peeters R, Sunaert S, Mantini D, Puts NAJ, Edden RAE, Swinnen SP. Age-related differences in GABA levels are driven by bulk tissue changes. Hum Brain Mapp 2018; 39:3652-3662. [PMID: 29722142 DOI: 10.1002/hbm.24201] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 03/23/2018] [Accepted: 04/20/2018] [Indexed: 01/07/2023] Open
Abstract
Levels of GABA, the main inhibitory neurotransmitter in the brain, can be regionally quantified using magnetic resonance spectroscopy (MRS). Although GABA is crucial for efficient neuronal functioning, little is known about age-related differences in GABA levels and their relationship with age-related changes in brain structure. Here, we investigated the effect of age on GABA levels within the left sensorimotor cortex and the occipital cortex in a sample of 85 young and 85 older adults using the MEGA-PRESS sequence. Because the distribution of GABA varies across different brain tissues, various correction methods are available to account for this variation. Considering that these correction methods are highly dependent on the tissue composition of the voxel of interest, we examined differences in voxel composition between age groups and the impact of these various correction methods on the identification of age-related differences in GABA levels. Results indicated that, within both voxels of interest, older (as compared to young adults) exhibited smaller gray matter fraction accompanied by larger fraction of cerebrospinal fluid. Whereas uncorrected GABA levels were significantly lower in older as compared to young adults, this age effect was absent when GABA levels were corrected for voxel composition. These results suggest that age-related differences in GABA levels are at least partly driven by the age-related gray matter loss. However, as alterations in GABA levels might be region-specific, further research should clarify to what extent gray matter changes may account for age-related differences in GABA levels within other brain regions.
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Affiliation(s)
- Celine Maes
- Movement control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Lize Hermans
- Movement control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Lisa Pauwels
- Movement control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Sima Chalavi
- Movement control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Inge Leunissen
- Movement control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Oron Levin
- Movement control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Koen Cuypers
- Movement control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium.,REVAL Research Institute, Hasselt University, Agoralaan, Building A, Diepenbeek, B-3590, Belgium
| | - Ronald Peeters
- Department of Imaging and Pathology, KU Leuven, Leuven, Belgium.,Department of Radiology, University Hospitals Leuven, Gasthuisberg, UZ, Leuven, Belgium
| | - Stefan Sunaert
- Department of Imaging and Pathology, KU Leuven, Leuven, Belgium.,Department of Radiology, University Hospitals Leuven, Gasthuisberg, UZ, Leuven, Belgium
| | - Dante Mantini
- Movement control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Nicolaas A J Puts
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Richard A E Edden
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Stephan P Swinnen
- Movement control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium.,Leuven Brain Institute (LBI), Leuven, Belgium
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77
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Abstract
PURPOSE OF REVIEW An increase in oscillatory activity in the γ-frequency band (approximately 50-100 Hz) has long been noted during human movement. However, its functional role has been difficult to elucidate. The advent of novel techniques, particularly transcranial alternating current stimulation (tACS), has dramatically increased our ability to study γ oscillations. Here, we review our current understanding of the role of γ oscillations in the human motor cortex, with reference to γ activity outside the motor system, and evidence from animal models. RECENT FINDINGS Evidence for the neurophysiological basis of human γ oscillations is beginning to emerge. Multimodal studies, essential given the necessarily indirect measurements acquired in humans, are beginning to provide convergent evidence for the role of γ oscillations in movement, and their relationship to plasticity. SUMMARY Human motor cortical γ oscillations appear to play a key role in movement, and relate to learning. However, there are still major questions to be answered about their physiological basis and precise role in human plasticity. It is to be hoped that future research will take advantage of recent technical advances and the physiological basis and functional significance of this intriguing and important brain rhythm will be fully elucidated.
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Affiliation(s)
- Magdalena Nowak
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 9DU UK
- Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford, OX3 7JX UK
| | - Catharina Zich
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 9DU UK
- Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford, OX3 7JX UK
| | - Charlotte J. Stagg
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 9DU UK
- Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford, OX3 7JX UK
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78
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Hermans L, Levin O, Maes C, van Ruitenbeek P, Heise KF, Edden RAE, Puts NAJ, Peeters R, King BR, Meesen RLJ, Leunissen I, Swinnen SP, Cuypers K. GABA levels and measures of intracortical and interhemispheric excitability in healthy young and older adults: an MRS-TMS study. Neurobiol Aging 2018; 65:168-177. [PMID: 29494863 DOI: 10.1016/j.neurobiolaging.2018.01.023] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 01/24/2018] [Accepted: 01/26/2018] [Indexed: 12/24/2022]
Abstract
Edited magnetic resonance spectroscopy (MRS) and transcranial magnetic stimulation (TMS) have often been used to study the integrity of the GABAergic neurotransmission system in healthy aging. To investigate whether the measurement outcomes obtained with these 2 techniques are associated with each other in older human adults, gamma-aminobutyric acid (GABA) levels in the left sensorimotor cortex were assessed with edited MRS in 28 older (63-74 years) and 28 young adults (19-34 years). TMS at rest was then used to measure intracortical inhibition (short-interval intracortical inhibition/long-interval intracortical inhibition), intracortical facilitation, interhemispheric inhibition from left to right primary motor cortex (M1) and recruitment curves of left and right M1. Our observations showed that short-interval intracortical inhibition and long-interval intracortical inhibition in the left M1 were reduced in older adults, while GABA levels did not significantly differ between age groups. Furthermore, MRS-assessed GABA within left sensorimotor cortex was not correlated with TMS-assessed cortical excitability or inhibition. These observations suggest that healthy aging gives rise to altered inhibition at the postsynaptic receptor level, which does not seem to be associated with MRS-assessed GABA+ levels.
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Affiliation(s)
- Lize Hermans
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Oron Levin
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Celine Maes
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Peter van Ruitenbeek
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium; Department of Neuropsychology and Psychopharmacology, Maastricht University, Maastricht, MD, the Netherlands
| | - Kirstin-Friederike Heise
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Richard A E Edden
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA; Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Nicolaas A J Puts
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA; Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Ronald Peeters
- Department of Imaging & Pathology, Biomedical Sciences Group, KU Leuven, Leuven, Belgium
| | - Bradley R King
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Raf L J Meesen
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium; Rehabilitation Research Centre, Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Diepenbeek, Belgium
| | - Inge Leunissen
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Stephan P Swinnen
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium; Leuven Research Institute for Neuroscience & Disease (LIND), KU Leuven, Leuven, Belgium
| | - Koen Cuypers
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium; Rehabilitation Research Centre, Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Diepenbeek, Belgium.
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79
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Coxon JP, Cash RFH, Hendrikse JJ, Rogasch NC, Stavrinos E, Suo C, Yücel M. GABA concentration in sensorimotor cortex following high-intensity exercise and relationship to lactate levels. J Physiol 2017; 596:691-702. [PMID: 29159914 DOI: 10.1113/jp274660] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 11/06/2017] [Indexed: 12/13/2022] Open
Abstract
KEY POINTS Magnetic resonance spectroscopy was conducted before and after high-intensity interval exercise. Sensorimotor cortex GABA concentration increased by 20%. The increase was positively correlated with the increase in blood lactate. There was no change in dorsolateral prefrontal cortex. There were no changes in the glutamate-glutamine-glutathione peak. ABSTRACT High-intensity exercise increases the concentration of circulating lactate. Cortical uptake of blood borne lactate increases during and after exercise; however, the potential relationship with changes in the concentration of neurometabolites remains unclear. Although changes in neurometabolite concentration have previously been demonstrated in primary visual cortex after exercise, it remains unknown whether these changes extend to regions such as the sensorimotor cortex (SM) or executive regions such as the dorsolateral prefrontal cortex (DLPFC). In the present study, we explored the acute after-effects of high-intensity interval training (HIIT) on the concentration of gamma-Aminobutyric acid (GABA) and the combined glutamate-glutamine-glutathione (Glx) spectral peak in the SM and DLPFC, as well as the relationship with blood lactate levels. Following HIIT, there was a robust increase in GABA concentration in the SM, as evident across the majority of participants. This change was not observed in the DLPFC. Furthermore, the increase in SM GABA was positively correlated with an increase in blood lactate. There were no changes in Glx concentration in either region. The observed increase in SM GABA concentration implies functional relevance, whereas the correlation with lactate levels may relate to the metabolic fate of exercise-derived lactate that crosses the blood-brain barrier.
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Affiliation(s)
- James P Coxon
- School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences (MICCN), Monash University, Clayton, VIC, Australia
| | - Robin F H Cash
- Monash Alfred Psychiatry Research Centre, Monash University Central Clinical School and The Alfred, Melbourne, VIC, Australia
| | - Joshua J Hendrikse
- School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences (MICCN), Monash University, Clayton, VIC, Australia
| | - Nigel C Rogasch
- School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences (MICCN), Monash University, Clayton, VIC, Australia
| | - Ellen Stavrinos
- School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences (MICCN), Monash University, Clayton, VIC, Australia
| | - Chao Suo
- School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences (MICCN), Monash University, Clayton, VIC, Australia
| | - Murat Yücel
- School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences (MICCN), Monash University, Clayton, VIC, Australia
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80
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Neuroimaging studies of GABA in schizophrenia: a systematic review with meta-analysis. Transl Psychiatry 2017; 7:e1147. [PMID: 28585933 PMCID: PMC5537645 DOI: 10.1038/tp.2017.124] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 04/26/2017] [Accepted: 05/03/2017] [Indexed: 01/17/2023] Open
Abstract
Data from animal models and from postmortem studies suggest that schizophrenia is associated with brain GABAergic dysfunction. The extent to which this is reflected in data from in vivo studies of GABA function in schizophrenia is unclear. The Medline database was searched to identify articles published until 21 October 2016. The search terms included GABA, proton magnetic resonance spectroscopy (1H-MRS), positron emission tomography (PET), single photon emission computed tomography (SPECT), schizophrenia and psychosis. Sixteen GABA 1H-MRS studies (538 controls, 526 patients) and seven PET/SPECT studies of GABAA/benzodiazepine receptor (GABAA/BZR) availability (118 controls, 113 patients) were identified. Meta-analyses of 1H-MRS GABA in the medial prefrontal cortex (mPFC), parietal/occipital cortex (POC) and striatum did not show significant group differences (mFC: g=-0.3, 409 patients, 495 controls, 95% confidence interval (CI): -0.6 to 0.1; POC: g=-0.3, 139 patients, 111 controls, 95% CI: -0.9 to 0.3; striatum: g=-0.004, 123 patients, 95 controls, 95% CI: -0.7 to 0.7). Heterogeneity across studies was high (I2>50%), and this was not explained by subsequent moderator or meta-regression analyses. There were insufficient PET/SPECT receptor availability studies for meta-analyses, but a systematic review did not suggest replicable group differences in regional GABAA/BZR availability. The current literature does not reveal consistent alterations in in vivo GABA neuroimaging measures in schizophrenia, as might be hypothesized from animal models and postmortem data. The analysis highlights the need for further GABA neuroimaging studies with improved methodology and addressing potential sources of heterogeneity.
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Mooney RA, Cirillo J, Byblow WD. GABA and primary motor cortex inhibition in young and older adults: a multimodal reliability study. J Neurophysiol 2017; 118:425-433. [PMID: 28424294 DOI: 10.1152/jn.00199.2017] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 04/19/2017] [Accepted: 04/19/2017] [Indexed: 12/14/2022] Open
Abstract
The effects of healthy aging on γ-aminobutyric acid (GABA) within primary motor cortex (M1) remain poorly understood. Studies have reported contrasting results, potentially due to limitations with the common assessment technique. The aim of the present study was to investigate the effect of healthy aging on M1 GABA concentration and neurotransmission using a multimodal approach. Fifteen young and sixteen older adults participated in this study. Magnetic resonance spectroscopy (MRS) was used to measure M1 GABA concentration. Single-pulse and threshold-tracking paired-pulse transcranial magnetic stimulation (TMS) protocols were used to examine cortical silent period duration, short- and long-interval intracortical inhibition (SICI and LICI), and late cortical disinhibition (LCD). The reliability of TMS measures was examined with intraclass correlation coefficient analyses. SICI at 1 ms was reduced in older adults (15.13 ± 2.59%) compared with young (25.66 ± 1.44%; P = 0.002). However, there was no age-related effect for cortical silent period duration, SICI at 3 ms, LICI, or LCD (all P > 0.66). The intersession reliability of threshold-tracking measures was good to excellent for both young (range 0.75-0.96) and older adults (range 0.88-0.93). Our findings indicate that extrasynaptic inhibition may be reduced with advancing age, whereas GABA concentration and synaptic inhibition are maintained. Furthermore, MRS and threshold-tracking TMS provide valid and reliable assessment of M1 GABA concentration and neurotransmission, respectively, in young and older adults.NEW & NOTEWORTHY γ-Aminobutyric acid (GABA) in primary motor cortex was assessed in young and older adults using magnetic resonance spectroscopy and threshold-tracking paired-pulse transcranial magnetic stimulation. Older adults exhibited reduced extrasynaptic inhibition (short-interval intracortical inhibition at 1 ms) compared with young, whereas GABA concentration and synaptic inhibition were similar between age groups. We demonstrate that magnetic resonance spectroscopy and threshold-tracking provide valid and reliable assessments of primary motor cortex GABA concentration and neurotransmission, respectively.
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Affiliation(s)
- Ronan A Mooney
- Movement Neuroscience Laboratory, Department of Exercise Sciences, The University of Auckland, New Zealand; and.,Centre for Brain Research, The University of Auckland, New Zealand
| | - John Cirillo
- Movement Neuroscience Laboratory, Department of Exercise Sciences, The University of Auckland, New Zealand; and.,Centre for Brain Research, The University of Auckland, New Zealand
| | - Winston D Byblow
- Movement Neuroscience Laboratory, Department of Exercise Sciences, The University of Auckland, New Zealand; and .,Centre for Brain Research, The University of Auckland, New Zealand
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