1
|
Zhou H, Hong T, Chen X, Su C, Teng B, Xi W, Cadet JL, Yang Y, Geng F, Hu Y. Glutamate concentration of medial prefrontal cortex is inversely associated with addictive behaviors: a translational study. Transl Psychiatry 2024; 14:433. [PMID: 39396023 DOI: 10.1038/s41398-024-03145-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 09/20/2024] [Accepted: 09/30/2024] [Indexed: 10/14/2024] Open
Abstract
In both preclinical and clinical settings, dysregulated frontostriatal circuits have been identified as the underlying neural substrates of compulsive seeking/taking behaviors manifested in substance use disorders and behavioral addictions including internet gaming disorder (IGD). However, the neurochemical substrates for these disorders remain elusive. The lack of comprehensive cognitive assessments in animal models has hampered our understanding of neural plasticity in addiction from these models. In this study, combining data from a rat model of compulsive taking/seeking and human participants with various levels of IGD severity, we investigated the relationship between regional glutamate (Glu) concentration and addictive behaviors. We found that Glu levels were significantly lower in the prelimbic cortex (PrL) of rats after 20-days of methamphetamine self-administration (SA), compared to controls. Glu concentration after a punishment phase negatively correlated with acute drug-seeking behavior. In addition, changes in Glu levels from a drug naïve state to compulsive drug taking patterns negatively correlated with drug-seeking during both acute and prolonged abstinence. The human data revealed a significant negative correlation between Glu concentration in the dorsal anterior cingulate cortex (dACC), the human PrL counterpart, and symptoms of IGD. Interestingly, there was a positive correlation between Glu levels in the dACC and self-control, as well as mindful awareness. Further analysis revealed that the dACC Glu concentration mediated the relationship between self-control/mindful awareness and IGD symptoms. These results provide convergent evidence for a protective role of dACC/PrL in addiction, suggesting interventions to enhance dACC glutamatergic functions as a potential strategy for addiction prevention and treatment.
Collapse
Affiliation(s)
- Hui Zhou
- Department of Psychology and Behavioral Sciences, Zhejiang University, Hangzhou, 311100, China
- The State Key Lab of Brain-Machine Intelligence, Zhejiang University, Hangzhou, 311100, China
| | - Tiantian Hong
- Department of Psychology and Behavioral Sciences, Zhejiang University, Hangzhou, 311100, China
| | - Xi Chen
- Department of Psychiatry, Harvard Medical School, Boston, MA, 02115, USA
| | - Conghui Su
- Department of Psychology and Behavioral Sciences, Zhejiang University, Hangzhou, 311100, China
| | - Binyu Teng
- Department of Psychology and Behavioral Sciences, Zhejiang University, Hangzhou, 311100, China
| | - Wan Xi
- Department of Psychology and Behavioral Sciences, Zhejiang University, Hangzhou, 311100, China
| | - Jean Lud Cadet
- Molecular Neuropsychiatry Research Branch, National Institute on Drug Abuse, Intramural Research Programs, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Yihong Yang
- Neuroimaging Research Branch, National Institute on Drug Abuse, Intramural Research Programs, National Institutes of Health, Baltimore, MD, 21224, USA.
| | - Fengji Geng
- Department of Curriculum and Learning Sciences, Zhejiang University, Hangzhou, 311100, China.
| | - Yuzheng Hu
- Department of Psychology and Behavioral Sciences, Zhejiang University, Hangzhou, 311100, China.
- The State Key Lab of Brain-Machine Intelligence, Zhejiang University, Hangzhou, 311100, China.
- MOE Frontiers Science Center for Brain Science & Brain-Machine Integration, Zhejiang University, Hangzhou, 311100, China.
- Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province, School of Medicine, Hangzhou City University, Hangzhou, 310015, China.
| |
Collapse
|
2
|
Lopes JJ, Carruthers SP, Meyer D, Dean B, Rossell SL. Glutamatergic neurotransmission in schizophrenia: A systematic review and quantitative synthesis of proton magnetic resonance spectroscopy studies across schizophrenia spectrum disorders. Aust N Z J Psychiatry 2024:48674241254216. [PMID: 38812258 DOI: 10.1177/00048674241254216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
OBJECTIVE Studies using proton magnetic resonance spectroscopy reveal substantial inconsistencies in the levels of brain glutamate, glutamine and glutamate + glutamine across schizophrenia spectrum disorders. This systematic review employs qualitative and quantitative methods to analyse the patterns and relationships between glutamatergic metabolites, schizophrenia spectrum disorders and brain regions. METHODS A literature search was conducted using various databases with keywords including glutamate, glutamine, schizophrenia, psychosis and proton magnetic resonance spectroscopy. Inclusion criteria were limited to case-control studies that reported glutamatergic metabolite levels in adult patients with a schizophrenia spectrum disorder diagnosis - i.e. first-episode psychosis, schizophrenia, treatment-resistant schizophrenia and/or ultra-treatment-resistant schizophrenia - using proton magnetic resonance spectroscopy at 3 T or above. Pooled study data were synthesized and analysed. RESULTS A total of 92 studies met the inclusion criteria, including 2721 healthy controls and 2822 schizophrenia spectrum disorder participants. Glu levels were higher in the basal ganglia, frontal cortex and medial prefrontal of first-episode psychosis participants, contrasting overall lower levels in schizophrenia participants. For Gln, strong differences in metabolite levels were evident in the basal ganglia, dorsolateral prefrontal cortex and frontal cortex, with first-episode psychosis showing significantly higher levels in the basal ganglia. In glutamate + glutamine, higher metabolite levels were found across schizophrenia spectrum disorder groups, particularly in the basal ganglia and dorsolateral prefrontal cortex of treatment-resistant schizophrenia participants. Significant relationships were found between metabolite levels and medication status, clinical measures and methodological variables. CONCLUSION The review highlights abnormal glutamatergic metabolite levels throughout schizophrenia spectrum disorders and in specific brain regions. The review underscores the importance of standardized future research assessing glutamatergic metabolites using proton magnetic resonance spectroscopy due to considerable literature heterogeneity.
Collapse
Affiliation(s)
- Jamie J Lopes
- Centre for Mental Health, Swinburne University of Technology, Melbourne, VIC, Australia
| | - Sean P Carruthers
- Centre for Mental Health, Swinburne University of Technology, Melbourne, VIC, Australia
| | - Denny Meyer
- Centre for Mental Health, Swinburne University of Technology, Melbourne, VIC, Australia
| | - Brian Dean
- Centre for Mental Health, Swinburne University of Technology, Melbourne, VIC, Australia
- Molecular Psychiatry Laboratory, The Florey Institute of Neuroscience and Mental Health, Melbourne, VIC, Australia
| | - Susan L Rossell
- Centre for Mental Health, Swinburne University of Technology, Melbourne, VIC, Australia
- Department of Psychiatry, St Vincent's Hospital, Melbourne, VIC, Australia
| |
Collapse
|
3
|
Fan L, Liang L, Wang Y, Ma X, Yuan L, Ouyang L, He Y, Li Z, Li C, Chen X, Palaniyappan L. Glutamatergic basis of antipsychotic response in first-episode psychosis: a dual voxel study of the anterior cingulate cortex. Neuropsychopharmacology 2024; 49:845-853. [PMID: 37752221 PMCID: PMC10948866 DOI: 10.1038/s41386-023-01741-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 07/31/2023] [Accepted: 09/11/2023] [Indexed: 09/28/2023]
Abstract
A subgroup of patients with schizophrenia is believed to have aberrant excess of glutamate in the frontal cortex; this subgroup is thought to show poor response to first-line antipsychotic treatments that focus on dopamine blockade. If we can identify this subgroup early in the course of illness, we can reduce the repeated use of first-line antipsychotics and potentially stratify first-episode patients to intervene early with second-line treatments such as clozapine. The use of proton magnetic resonance spectroscopy (1H-MRS) to measure glutamate and Glx (glutamate plus glutamine) may provide a means for such a stratification. We must first establish if there is robust evidence linking elevations in anterior cingulate cortex (ACC) glutamate metabolites to poor response, and determine if the use of antipsychotics worsens the glutamatergic excess in eventual nonresponders. In this study, we estimated glutamate levels at baseline in 42 drug-naive patients with schizophrenia. We then treated them all with risperidone at a standard dose range of 2-6 mg/day and followed them up for 3 months to categorize their response status. We expected to see baseline "hyperglutamatergia" in nonresponders, and expected this to worsen over time at the follow-up. In line with our predictions, nonresponders had higher glutamate than responders, but patients as a group did not differ in glutamate and Glx from the healthy control (HC) group before treatment-onset (F1,79 = 3.20, p = 0.046, partial η2 = 0.075). Glutamatergic metabolites did not change significantly over time in both nonresponders and responders over the 3 months of antipsychotic exposure (F1,31 = 1.26, p = 0.270, partial η2 = 0.039). We conclude that the use of antipsychotics without prior knowledge of later response delays symptom relief in a subgroup of first-episode patients, but does not worsen the glutamatergic excess seen at the baseline. Given the current practice of nonstratified use of antipsychotics, longer-time follow-up MRS studies are required to see if improvement in symptoms accompanies a dynamic shift in glutamate profile.
Collapse
Affiliation(s)
- Lejia Fan
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
- Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montreal, QC, Canada
| | - Liangbing Liang
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Yujue Wang
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Xiaoqian Ma
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Liu Yuan
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Lijun Ouyang
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Ying He
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Zongchang Li
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Chunwang Li
- Department of Radiology, Hunan Children's Hospital, Changsha, China
| | - Xiaogang Chen
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China.
| | - Lena Palaniyappan
- Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montreal, QC, Canada.
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada.
| |
Collapse
|
4
|
Singh U, Das B, Khanra S, Roy C. Resting state and activated brain glutamate-glutamine, brain lactate, cognition, and psychopathology among males with schizophrenia: A 3 Tesla proton magnetic resonance spectroscopic (1H-MRS) study. Indian J Psychiatry 2024; 66:82-89. [PMID: 38419937 PMCID: PMC10898519 DOI: 10.4103/indianjpsychiatry.indianjpsychiatry_621_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 11/09/2023] [Accepted: 12/25/2023] [Indexed: 03/02/2024] Open
Abstract
Background Research on glutamate (Glu) in schizophrenia has so far been inconclusive. Based on preclinical studies on Glu lactate interaction, researchers have now focused on brain lactate level as a sign of major pathology, including cognitive dysfunctions in the brain. Our study aimed to examine changes at resting and activated states in brain lactate and Glu-glutamine (Glx) at the anterior cingulate cortex (ACC) in schizophrenia. Methods A hospital-based prospective study was conducted with twenty-two male cases of schizophrenia and matched healthy controls (HCs). Positive and Negative Syndrome Scale (PANSS), Montreal Cognitive Assessment (MoCA), and Stroop tasks were administered among patients. Brain lactate and Glx at ACC were measured at resting state and during the Stroop test with proton magnetic resonance spectroscopy (1H-MRS) both at baseline and at remission and once among HC. Result Though MoCA scores improved significantly (P < 0.001) at remission from baseline among cases, repeated-measures analysis of variance (RM-ANOVA) did not find a significant time effect for Glx (P = 0.82) and lactate (P = 0.30) among cases from baseline to remission. Glx and lactate changed differently from baseline to remission. Conclusion Our study did not find significant differences in Glx and lactate between schizophrenia patients and HC. No significant time effect on Glx and lactate was observed from baseline to remission among schizophrenia cases. Different changes observed in Glx and lactate from baseline to remission require replication in future studies with larger sample size, longer follow-up period, and multivoxel MR assessment.
Collapse
Affiliation(s)
- Ujjwal Singh
- Department of Psychiatry, Central Institute of Psychiatry, Ranchi, Jharkhand, India
| | - Basudeb Das
- Department of Psychiatry, Central Institute of Psychiatry, Ranchi, Jharkhand, India
| | - Sourav Khanra
- Department of Psychiatry, Central Institute of Psychiatry, Ranchi, Jharkhand, India
| | - Chandramouli Roy
- Department of Psychiatry, Central Institute of Psychiatry, Ranchi, Jharkhand, India
| |
Collapse
|
5
|
Gudmundson AT, Koo A, Virovka A, Amirault AL, Soo M, Cho JH, Oeltzschner G, Edden RAE, Stark CEL. Meta-analysis and open-source database for in vivo brain Magnetic Resonance spectroscopy in health and disease. Anal Biochem 2023; 676:115227. [PMID: 37423487 PMCID: PMC10561665 DOI: 10.1016/j.ab.2023.115227] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 06/15/2023] [Accepted: 06/26/2023] [Indexed: 07/11/2023]
Abstract
Proton (1H) Magnetic Resonance Spectroscopy (MRS) is a non-invasive tool capable of quantifying brain metabolite concentrations in vivo. Prioritization of standardization and accessibility in the field has led to the development of universal pulse sequences, methodological consensus recommendations, and the development of open-source analysis software packages. One on-going challenge is methodological validation with ground-truth data. As ground-truths are rarely available for in vivo measurements, data simulations have become an important tool. The diverse literature of metabolite measurements has made it challenging to define ranges to be used within simulations. Especially for the development of deep learning and machine learning algorithms, simulations must be able to produce accurate spectra capturing all the nuances of in vivo data. Therefore, we sought to determine the physiological ranges and relaxation rates of brain metabolites which can be used both in data simulations and as reference estimates. Using the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, we've identified relevant MRS research articles and created an open-source database containing methods, results, and other article information as a resource. Using this database, expectation values and ranges for metabolite concentrations and T2 relaxation times are established based upon a meta-analyses of healthy and diseased brains.
Collapse
Affiliation(s)
- Aaron T Gudmundson
- 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
| | - Annie Koo
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, USA
| | - Anna Virovka
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, USA
| | - Alyssa L Amirault
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, USA
| | - Madelene Soo
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, USA
| | - Jocelyn H Cho
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, USA
| | - Georg Oeltzschner
- 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
| | - Richard A E 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
| | - Craig E L Stark
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, USA.
| |
Collapse
|
6
|
Cai XL, Pu CC, Zhou SZ, Wang Y, Huang J, Lui SSY, Møller A, Cheung EFC, Madsen KH, Xue R, Yu X, Chan RCK. Anterior cingulate glutamate levels associate with functional activation and connectivity during sensory integration in schizophrenia: a multimodal 1H-MRS and fMRI study. Psychol Med 2023; 53:4904-4914. [PMID: 35791929 DOI: 10.1017/s0033291722001817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Glutamatergic dysfunction has been implicated in sensory integration deficits in schizophrenia, yet how glutamatergic function contributes to behavioural impairments and neural activities of sensory integration remains unknown. METHODS Fifty schizophrenia patients and 43 healthy controls completed behavioural assessments for sensory integration and underwent magnetic resonance spectroscopy (MRS) for measuring the anterior cingulate cortex (ACC) glutamate levels. The correlation between glutamate levels and behavioural sensory integration deficits was examined in each group. A subsample of 20 pairs of patients and controls further completed an audiovisual sensory integration functional magnetic resonance imaging (fMRI) task. Blood Oxygenation Level Dependent (BOLD) activation and task-dependent functional connectivity (FC) were assessed based on fMRI data. Full factorial analyses were performed to examine the Group-by-Glutamate Level interaction effects on fMRI measurements (group differences in correlation between glutamate levels and fMRI measurements) and the correlation between glutamate levels and fMRI measurements within each group. RESULTS We found that schizophrenia patients exhibited impaired sensory integration which was positively correlated with ACC glutamate levels. Multimodal analyses showed significantly Group-by-Glutamate Level interaction effects on BOLD activation as well as task-dependent FC in a 'cortico-subcortical-cortical' network (including medial frontal gyrus, precuneus, ACC, middle cingulate gyrus, thalamus and caudate) with positive correlations in patients and negative in controls. CONCLUSIONS Our findings indicate that ACC glutamate influences neural activities in a large-scale network during sensory integration, but the effects have opposite directionality between schizophrenia patients and healthy people. This implicates the crucial role of glutamatergic system in sensory integration processing in schizophrenia.
Collapse
Affiliation(s)
- Xin-Lu Cai
- Neuropsychology and Applied Cognitive Neuroscience Laboratory, CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Sino-Danish College, University of Chinese Academy of Sciences, Beijing, China
- Sino-Danish Centre for Education and Research, Beijing, China
| | - Cheng-Cheng Pu
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Beijing, China
- NHC Key Laboratory of Mental Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, China
| | - Shu-Zhe Zhou
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Beijing, China
- NHC Key Laboratory of Mental Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, China
| | - Yi Wang
- Neuropsychology and Applied Cognitive Neuroscience Laboratory, CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Jia Huang
- Neuropsychology and Applied Cognitive Neuroscience Laboratory, CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Simon S Y Lui
- Department of Psychiatry, School of Clinical Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China
| | - Arne Møller
- Sino-Danish College, University of Chinese Academy of Sciences, Beijing, China
- Sino-Danish Centre for Education and Research, Beijing, China
- Centre of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark
- Department of Nuclear Medicine and PET Centre, Aarhus University Hospital, Aarhus, Denmark
| | - Eric F C Cheung
- Castle Peak Hospital, Hong Kong Special Administrative Region, China
| | - Kristoffer H Madsen
- Sino-Danish Centre for Education and Research, Beijing, China
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital, Amager and Hvidovre, Denmark
- Department of Applied Mathematics and Computer Science, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Rong Xue
- Sino-Danish College, University of Chinese Academy of Sciences, Beijing, China
- Sino-Danish Centre for Education and Research, Beijing, China
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- Beijing Institute for Brain Disorders, Beijing, China
| | - Xin Yu
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Beijing, China
- NHC Key Laboratory of Mental Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, China
| | - Raymond C K Chan
- Neuropsychology and Applied Cognitive Neuroscience Laboratory, CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Sino-Danish College, University of Chinese Academy of Sciences, Beijing, China
- Sino-Danish Centre for Education and Research, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
- Department of Diagnostic Radiology, the University of Hong Kong, Hong Kong Special Administrative Region, China
| |
Collapse
|
7
|
Bang JW, Parra C, Yu K, Wollstein G, Schuman JS, Chan KC. GABA decrease is associated with degraded neural specificity in the visual cortex of glaucoma patients. Commun Biol 2023; 6:679. [PMID: 37386293 PMCID: PMC10310759 DOI: 10.1038/s42003-023-04918-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 05/05/2023] [Indexed: 07/01/2023] Open
Abstract
Glaucoma is an age-related neurodegenerative disease of the visual system, affecting both the eye and the brain. Yet its underlying metabolic mechanisms and neurobehavioral relevance remain largely unclear. Here, using proton magnetic resonance spectroscopy and functional magnetic resonance imaging, we investigated the GABAergic and glutamatergic systems in the visual cortex of glaucoma patients, as well as neural specificity, which is shaped by GABA and glutamate signals and underlies efficient sensory and cognitive functions. Our study shows that among the older adults, both GABA and glutamate levels decrease with increasing glaucoma severity regardless of age. Further, our study shows that the reduction of GABA but not glutamate predicts the neural specificity. This association is independent of the impairments on the retina structure, age, and the gray matter volume of the visual cortex. Our results suggest that glaucoma-specific decline of GABA undermines neural specificity in the visual cortex and that targeting GABA could improve the neural specificity in glaucoma.
Collapse
Affiliation(s)
- Ji Won Bang
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, 10017, USA.
| | - Carlos Parra
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, 10017, USA
| | - Kevin Yu
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, 10017, USA
| | - Gadi Wollstein
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, 10017, USA
- Center for Neural Science, College of Arts and Science, New York University, New York, New York, 10003, USA
- Department of Biomedical Engineering, Tandon School of Engineering, New York University, New York, New York, 11201, USA
| | - Joel S Schuman
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, 10017, USA
- Center for Neural Science, College of Arts and Science, New York University, New York, New York, 10003, USA
- Department of Biomedical Engineering, Tandon School of Engineering, New York University, New York, New York, 11201, USA
- Neuroscience Institute, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, 10016, USA
| | - Kevin C Chan
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, 10017, USA.
- Center for Neural Science, College of Arts and Science, New York University, New York, New York, 10003, USA.
- Department of Biomedical Engineering, Tandon School of Engineering, New York University, New York, New York, 11201, USA.
- Neuroscience Institute, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, 10016, USA.
- Department of Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, 10016, USA.
| |
Collapse
|
8
|
Gudmundson AT, Koo A, Virovka A, Amirault AL, Soo M, Cho JH, Oeltzschner G, Edden RA, Stark C. Meta-analysis and Open-source Database for In Vivo Brain Magnetic Resonance Spectroscopy in Health and Disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.10.528046. [PMID: 37205343 PMCID: PMC10187197 DOI: 10.1101/2023.02.10.528046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Proton ( 1 H) Magnetic Resonance Spectroscopy (MRS) is a non-invasive tool capable of quantifying brain metabolite concentrations in vivo . Prioritization of standardization and accessibility in the field has led to the development of universal pulse sequences, methodological consensus recommendations, and the development of open-source analysis software packages. One on-going challenge is methodological validation with ground-truth data. As ground-truths are rarely available for in vivo measurements, data simulations have become an important tool. The diverse literature of metabolite measurements has made it challenging to define ranges to be used within simulations. Especially for the development of deep learning and machine learning algorithms, simulations must be able to produce accurate spectra capturing all the nuances of in vivo data. Therefore, we sought to determine the physiological ranges and relaxation rates of brain metabolites which can be used both in data simulations and as reference estimates. Using the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, we've identified relevant MRS research articles and created an open-source database containing methods, results, and other article information as a resource. Using this database, expectation values and ranges for metabolite concentrations and T 2 relaxation times are established based upon a meta-analyses of healthy and diseased brains.
Collapse
Affiliation(s)
- Aaron T. Gudmundson
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD
| | - Annie Koo
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA
| | - Anna Virovka
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA
| | - Alyssa L. Amirault
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA
| | - Madelene Soo
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA
| | - Jocelyn H. Cho
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA
| | - Georg Oeltzschner
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD
| | - Richard A.E. Edden
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD
| | - Craig Stark
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA
| |
Collapse
|
9
|
Wang M, Barker PB, Cascella NG, Coughlin JM, Nestadt G, Nucifora FC, Sedlak TW, Kelly A, Younes L, Geman D, Palaniyappan L, Sawa A, Yang K. Longitudinal changes in brain metabolites in healthy controls and patients with first episode psychosis: a 7-Tesla MRS study. Mol Psychiatry 2023; 28:2018-2029. [PMID: 36732587 PMCID: PMC10394114 DOI: 10.1038/s41380-023-01969-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 01/13/2023] [Accepted: 01/17/2023] [Indexed: 02/04/2023]
Abstract
Seven Tesla magnetic resonance spectroscopy (7T MRS) offers a precise measurement of metabolic levels in the human brain via a non-invasive approach. Studying longitudinal changes in brain metabolites could help evaluate the characteristics of disease over time. This approach may also shed light on how the age of study participants and duration of illness may influence these metabolites. This study used 7T MRS to investigate longitudinal patterns of brain metabolites in young adulthood in both healthy controls and patients. A four-year longitudinal cohort with 38 patients with first episode psychosis (onset within 2 years) and 48 healthy controls was used to examine 10 brain metabolites in 5 brain regions associated with the pathophysiology of psychosis in a comprehensive manner. Both patients and controls were found to have significant longitudinal reductions in glutamate in the anterior cingulate cortex (ACC). Only patients were found to have a significant decrease over time in γ-aminobutyric acid, N-acetyl aspartate, myo-inositol, total choline, and total creatine in the ACC. Together we highlight the ACC with dynamic changes in several metabolites in early-stage psychosis, in contrast to the other 4 brain regions that also are known to play roles in psychosis. Meanwhile, glutathione was uniquely found to have a near zero annual percentage change in both patients and controls in all 5 brain regions during a four-year follow-up in young adulthood. Given that a reduction of the glutathione in the ACC has been reported as a feature of treatment-refractory psychosis, this observation further supports the potential of glutathione as a biomarker for this subset of patients with psychosis.
Collapse
Affiliation(s)
- Min Wang
- Russell H Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, China
| | - Peter B Barker
- Russell H Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA.
| | - Nicola G Cascella
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jennifer M Coughlin
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Gerald Nestadt
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Frederick C Nucifora
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Thomas W Sedlak
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Alexandra Kelly
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Laurent Younes
- Department of Applied Mathematics and Statistics, Johns Hopkins University, Baltimore, MD, USA
| | - Donald Geman
- Department of Applied Mathematics and Statistics, Johns Hopkins University, Baltimore, MD, USA
| | - Lena Palaniyappan
- Robarts Research Institution, University of Western Ontario, London, ON, Canada
- Department of Psychiatry, University of Western Ontario, London, ON, Canada
- Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montreal, QC, Canada
| | - Akira Sawa
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA.
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Department of Mental Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA.
| | - Kun Yang
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| |
Collapse
|
10
|
Lahti AC. Discovery of early schizophrenia through neuroimaging. Psychiatry Res 2023; 322:114993. [PMID: 36773467 DOI: 10.1016/j.psychres.2022.114993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 11/22/2022] [Accepted: 11/27/2022] [Indexed: 11/29/2022]
Abstract
In order to understand the pathophysiology of schizophrenia we carried out a number of brain imaging studies in both medicated and unmedicated patients. In addition, to help unravel the pathophysiological mechanisms without the confound of prior exposure to antipsychotic medication or chronicity, we enrolled a large group of antipsychotic medication-naïve first episode psychosis patients at first treatment contact, and performed longitudinal multimodal neuroimaging studies over several months. In unmedicated patients we found both functional and structural connectivity alterations. Similarly, in medication-naïve patients we replicated many of our prior findings, suggesting that functional and structural connectivity alterations are core pathological features of the illness. We found that a longer duration of untreated psychosis, i.e. the time between first symptom onset and initial treatment contact, was associated with greater structural and functional connectivity abnormalities, which in turn was associated with worse subsequent clinical response to treatment. These results underscore the critical importance of early identification and treatment in patients with psychosis spectrum disorders.
Collapse
Affiliation(s)
- Adrienne C Lahti
- Department of Psychiatry and Behavioral Neurobiology, The University of Alabama at Birmingham, Birmingham, AL, United States.
| |
Collapse
|
11
|
Tangmose K, Rostrup E, Bojesen KB, Sigvard A, Jessen K, Johansen LB, Glenthøj BY, Nielsen MØ. Reward disturbances in antipsychotic-naïve patients with first-episode psychosis and their association to glutamate levels. Psychol Med 2023; 53:1629-1638. [PMID: 37010221 DOI: 10.1017/s0033291721003305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Aberrant anticipation of motivational salient events and processing of outcome evaluation in striatal and prefrontal regions have been suggested to underlie psychosis. Altered glutamate levels have likewise been linked to schizophrenia. Glutamatergic abnormalities may affect the processing of motivational salience and outcome evaluation. It remains unresolved, whether glutamatergic dysfunction is associated with the coding of motivational salience and outcome evaluation in antipsychotic-naïve patients with first-episode psychosis. METHODS Fifty-one antipsychotic-naïve patients with first-episode psychosis (22 ± 5.2 years, female/male: 31/20) and 52 healthy controls (HC) matched on age, sex, and parental education underwent functional magnetic resonance imaging and magnetic resonance spectroscopy (3T) in one session. Brain responses to motivational salience and negative outcome evaluation (NOE) were examined using a monetary incentive delay task. Glutamate levels were estimated in the left thalamus and anterior cingulate cortex using LCModel. RESULTS Patients displayed a positive signal change to NOE in the caudate (p = 0.001) and dorsolateral prefrontal cortex (DLPFC; p = 0.003) compared to HC. No group difference was observed in motivational salience or in levels of glutamate. There was a different association between NOE signal in the caudate and DLPFC and thalamic glutamate levels in patients and HC due to a negative correlation in patients (caudate: p = 0.004, DLPFC: p = 0.005) that was not seen in HC. CONCLUSIONS Our findings confirm prior findings of abnormal outcome evaluation as a part of the pathophysiology of schizophrenia. The results also suggest a possible link between thalamic glutamate and NOE signaling in patients with first-episode psychosis.
Collapse
Affiliation(s)
- Karen Tangmose
- Center for Neuropsychiatric Schizophrenia Research (CNSR) and Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS), Mental Health Center Glostrup, Glostrup, Denmark
- Department of Clinical Medicine Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Egill Rostrup
- Center for Neuropsychiatric Schizophrenia Research (CNSR) and Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS), Mental Health Center Glostrup, Glostrup, Denmark
- Functional Imaging Unit, Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet Glostrup, University of Copenhagen, Glostrup, Denmark
| | - Kirsten B Bojesen
- Center for Neuropsychiatric Schizophrenia Research (CNSR) and Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS), Mental Health Center Glostrup, Glostrup, Denmark
| | - Anne Sigvard
- Center for Neuropsychiatric Schizophrenia Research (CNSR) and Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS), Mental Health Center Glostrup, Glostrup, Denmark
- Department of Clinical Medicine Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kasper Jessen
- Center for Neuropsychiatric Schizophrenia Research (CNSR) and Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS), Mental Health Center Glostrup, Glostrup, Denmark
| | - Louise Baruël Johansen
- Center for Neuropsychiatric Schizophrenia Research (CNSR) and Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS), Mental Health Center Glostrup, Glostrup, Denmark
| | - Birte Y Glenthøj
- Center for Neuropsychiatric Schizophrenia Research (CNSR) and Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS), Mental Health Center Glostrup, Glostrup, Denmark
- Department of Clinical Medicine Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mette Ødegaard Nielsen
- Center for Neuropsychiatric Schizophrenia Research (CNSR) and Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS), Mental Health Center Glostrup, Glostrup, Denmark
- Department of Clinical Medicine Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
12
|
Yang F, Tan J, Huang Y, Xiao R, Wang X, Han Y. Altered Language-Related Effective Connectivity in Patients with Benign Childhood Epilepsy with Centrotemporal Spikes. Life (Basel) 2023; 13:life13020590. [PMID: 36836947 PMCID: PMC9960797 DOI: 10.3390/life13020590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 02/04/2023] [Accepted: 02/13/2023] [Indexed: 02/23/2023] Open
Abstract
Benign childhood epilepsy with centrotemporal spikes (BECTS) is one of the most common childhood epilepsy syndromes and may be associated with language deficits. Resting-state functional magnetic resonance imaging (fMRI) data were collected from a total of 78 children: 52 patients with BECTS (28 drug-naïve and 24 medicated) and 26 healthy controls (HC). Granger causality analysis (GCA) was used to investigate alterations in effective connectivity (EC) between the language network core node (Broca's area) and the whole brain. EC from Broca's area to the left Heschl's gyrus (HG), right putamen, and anterior cingulate cortex (ACC) was significantly increased, while EC from the bilateral putamen and left ACC to Broca's area was significantly decreased in BECTS. Moreover, altered EC of Broca's area to the right putamen was significantly positively correlated with verbal IQ (VIQ), while altered EC of Broca's area to the ACC showed significantly negative correlations with the frequency of seizures. Altered EC from the left putamen to Broca's area was also significantly negatively correlated with performance IQ (PIQ) and full-scale IQ (FSIQ) in the drug-naïve group. In addition, there was a significant positive correlation between the EC of Broca's area to the left HG and the number of seizures, as well as between the EC of Broca's area to the right putamen and the age at onset in the medicated group. These findings suggest abnormal causal effects on the language network related to Broca's area in children with BECTS. Longitudinal investigation of language network development and further follow-up may be needed to illuminate the changes in organization and rebalancing over time.
Collapse
Affiliation(s)
- Fei Yang
- Department of Neurology, First Affiliated Hospital of Kunming Medical University, Kunming 650051, China
| | - Juan Tan
- Department of Neurology, Affiliated Hospital of North Sichuan Medical College, Nanchong 637503, China
| | - Yue Huang
- Department of Pediatrics, Affiliated Hospital of North Sichuan Medical College, Nanchong 637503, China
| | - Ruhui Xiao
- Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong 637503, China
| | - Xiaoming Wang
- Department of Neurology, Affiliated Hospital of North Sichuan Medical College, Nanchong 637503, China
| | - Yanbing Han
- Department of Neurology, First Affiliated Hospital of Kunming Medical University, Kunming 650051, China
- Correspondence:
| |
Collapse
|
13
|
McHugo M, Avery S, Armstrong K, Rogers BP, Vandekar SN, Woodward ND, Blackford JU, Heckers S. Anterior hippocampal dysfunction in early psychosis: a 2-year follow-up study. Psychol Med 2023; 53:160-169. [PMID: 33875028 PMCID: PMC8919704 DOI: 10.1017/s0033291721001318] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Cross-sectional studies indicate that hippocampal function is abnormal across stages of psychosis. Neural theories of psychosis pathophysiology suggest that dysfunction worsens with illness stage. Here, we test the hypothesis that hippocampal function is impaired in the early stage of psychosis and declines further over the next 2 years. METHODS We measured hippocampal function over 2 years using a scene processing task in 147 participants (76 individuals in the early stage of a non-affective psychotic disorder and 71 demographically similar healthy control individuals). Two-year follow-up was completed in 97 individuals (50 early psychosis, 47 healthy control). Voxelwise longitudinal analysis of activation in response to scenes was carried out within a hippocampal region of interest to test for group differences at baseline and a group by time interaction. RESULTS At baseline, we observed lower anterior hippocampal activation in the early psychosis group relative to the healthy control group. Contrary to our hypothesis, hippocampal activation remained consistent and did not show the predicted decline over 2 years in the early psychosis group. Healthy controls showed a modest reduction in hippocampal activation after 2 years. CONCLUSIONS The results of this study suggest that hippocampal dysfunction in early psychosis does not worsen over 2 years and highlight the need for longer-term longitudinal studies.
Collapse
Affiliation(s)
- Maureen McHugo
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Suzanne Avery
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Kristan Armstrong
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Baxter P. Rogers
- Vanderbilt University Institute of Imaging Sciences, Nashville, TN, USA
| | - Simon N. Vandekar
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Neil D. Woodward
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jennifer Urbano Blackford
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Research and Development, Tennessee Valley Healthcare System, United States Department of Veteran Affairs
| | - Stephan Heckers
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| |
Collapse
|
14
|
Zahid U, Onwordi EC, Hedges EP, Wall MB, Modinos G, Murray RM, Egerton A. Neurofunctional correlates of glutamate and GABA imbalance in psychosis: A systematic review. Neurosci Biobehav Rev 2023; 144:105010. [PMID: 36549375 DOI: 10.1016/j.neubiorev.2022.105010] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 12/01/2022] [Accepted: 12/15/2022] [Indexed: 12/23/2022]
Abstract
Glutamatergic and GABAergic dysfunction are implicated in the pathophysiology of schizophrenia. Previous work has shown relationships between glutamate, GABA, and brain activity in healthy volunteers. We conducted a systematic review to evaluate whether these relationships are disrupted in psychosis. Primary outcomes were the relationship between metabolite levels and fMRI BOLD response in psychosis relative to healthy volunteers. 17 case-control studies met inclusion criteria (594 patients and 538 healthy volunteers). Replicated findings included that in psychosis, positive associations between ACC glutamate levels and brain activity are reduced during resting state conditions and increased during cognitive control tasks, and negative relationships between GABA and local activation in the ACC are reduced. There was evidence that antipsychotic medication may alter the relationship between glutamate levels and brain activity. Emerging literature is providing insights into disrupted relationships between neurometabolites and brain activity in psychosis. Future studies determining a link to clinical variables may develop this approach for biomarker applications, including development or targeting novel therapeutics.
Collapse
Affiliation(s)
- Uzma Zahid
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK; Department of Psychiatry, University of Oxford, UK.
| | - Ellis C Onwordi
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK; MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK; Institute of Clinical Sciences (ICS), Faculty of Medicine, Imperial College London, London, UK; South London and Maudsley NHS Foundation Trust, Camberwell, London, UK
| | - Emily P Hedges
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK
| | - Matthew B Wall
- Invicro London, Hammersmith Hospital, UK; Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, UK; Clinical Psychopharmacology Unit, University College London, UK
| | - Gemma Modinos
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK
| | - Robin M Murray
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK
| | - Alice Egerton
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK
| |
Collapse
|
15
|
Reddy-Thootkur M, Kraguljac NV, Lahti AC. The role of glutamate and GABA in cognitive dysfunction in schizophrenia and mood disorders - A systematic review of magnetic resonance spectroscopy studies. Schizophr Res 2022; 249:74-84. [PMID: 32107102 PMCID: PMC7874516 DOI: 10.1016/j.schres.2020.02.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 02/03/2020] [Accepted: 02/05/2020] [Indexed: 12/14/2022]
Abstract
Epidemiologic, genetic, and neurobiological studies suggest considerable overlap between schizophrenia and mood disorders. Importantly, both disorders are associated with a broad range of cognitive deficits as well as altered glutamatergic and GABAergic neurometabolism. We conducted a systematic review of magnetic resonance spectroscopy (MRS) studies investigating the relationship between glutamatergic and GABAergic neurometabolites and cognition in schizophrenia spectrum disorders and mood disorders. A literature search in Pubmed of studies published before April 15, 2019 was conducted and 37 studies were deemed eligible for systematic review. We found that alterations in glutamatergic and GABAergic neurotransmission have been identified relatively consistently in both schizophrenia and mood disorders. However, because of the vast heterogeneity of published studies in terms of illness stage, medication exposure, MRS acquisition parameters and data post-processing strategies, we still do not understand the relationship between those neurotransmitters and cognitive dysfunction in mental illness, which is a critical initial step for rational drug development. Our findings emphasize the need for coordinated multi-center studies that characterize cognitive function and its biological substrates in large and well-defined clinical populations, using harmonized imaging sequences and analytical methods with the goal to elucidate the underlying pathophysiological mechanisms and to inform future clinical trials.
Collapse
Affiliation(s)
- Mounica Reddy-Thootkur
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Nina Vanessa Kraguljac
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Adrienne Carol Lahti
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, United States of America.
| |
Collapse
|
16
|
Roberts RC, McCollum LA, Schoonover KE, Mabry SJ, Roche JK, Lahti AC. Ultrastructural evidence for glutamatergic dysregulation in schizophrenia. Schizophr Res 2022; 249:4-15. [PMID: 32014360 PMCID: PMC7392793 DOI: 10.1016/j.schres.2020.01.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 01/16/2020] [Accepted: 01/18/2020] [Indexed: 12/14/2022]
Abstract
The aim of this paper is to summarize ultrastructural evidence for glutamatergic dysregulation in several linked regions in postmortem schizophrenia brain. Following a brief summary of glutamate circuitry and how synapses are identified at the electron microscopic (EM) level, we will review EM pathology in the cortex and basal ganglia. We will include the effects of antipsychotic drugs and the relation of treatment response. We will discuss how these findings support or confirm other postmortem findings as well as imaging results. Briefly, synaptic and mitochondrial density in anterior cingulate cortex was decreased in schizophrenia, versus normal controls (NCs), in a selective layer specific pattern. In dorsal striatum, increases in excitatory synaptic density were detected in caudate matrix, a compartment associated with cognitive and motor function, and in the putamen patches, a region associated with limbic function and in the core of the nucleus accumbens. Patients who were treatment resistant or untreated had significantly elevated numbers of excitatory synapses in limbic striatal areas in comparison to NCs and responders. Protein levels of vGLUT2, found in subcortical glutamatergic neurons, were increased in the nucleus accumbens in schizophrenia. At the EM level, schizophrenia subjects had an increase in density of excitatory synapses in several areas of the basal ganglia. In the substantia nigra, the protein levels of vGLUT2 were elevated in untreated patients compared to NCs. The density of inhibitory synapses was decreased in schizophrenia versus NCs. In schizophrenia, glutamatergic synapses are differentially affected depending on the brain region, treatment status, and treatment response.
Collapse
Affiliation(s)
- Rosalinda C Roberts
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama, Birmingham, AL 35294, United States of America.
| | - Lesley A McCollum
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama, Birmingham, AL 35294, United States of America
| | - Kirsten E Schoonover
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama, Birmingham, AL 35294, United States of America
| | - Samuel J Mabry
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama, Birmingham, AL 35294, United States of America
| | - Joy K Roche
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama, Birmingham, AL 35294, United States of America
| | - Adrienne C Lahti
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama, Birmingham, AL 35294, United States of America
| |
Collapse
|
17
|
Nelson EA, Kraguljac NV, Maximo JO, Armstrong W, Lahti AC. Dorsal striatial hypoconnectivity predicts antipsychotic medication treatment response in first-episode psychosis and unmedicated patients with schizophrenia. Brain Behav 2022; 12:e2625. [PMID: 36237115 PMCID: PMC9660417 DOI: 10.1002/brb3.2625] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 03/28/2022] [Accepted: 04/24/2022] [Indexed: 01/10/2023] Open
Abstract
INTRODUCTION The dorsal striatum, comprised of the caudate and putamen, is implicated in the pathophysiology of psychosis spectrum disorders. Given the high concentration of dopamine receptors in the striatum, striatal dopamine imbalance is a likely cause in cortico-striatal dysconnectivity. There is great interest in understanding the relationship between striatal abnormalities in psychosis and antipsychotic treatment response, but few studies have considered differential involvement of the caudate and putamen. This study's goals were twofold. First, identify patterns of dorsal striatal dysconnectivity for the caudate and putamen separately in patients with a psychosis spectrum disorder; second, determine if these dysconnectivity patterns were predictive of treatment response. METHODS Using resting state functional connectivity, we evaluated dorsal striatal connectivity using separate bilateral caudate and putamen seed regions in two cohorts of subjects: a cohort of 71 medication-naïve first episode psychosis patients and a cohort of 42 unmedicated patients with schizophrenia (along with matched controls). Patient and control connectivity maps were contrasted for each cohort. After receiving 6 weeks of risperidone treatment, patients' clinical response was calculated. We used regression analyses to determine the relationship between baseline dysconnectivity and treatment response. RESULTS This dysconnectivity was also predictive of treatment response in both cohorts. DISCUSSION These findings suggest that the caudate may be more of a driving factor than the putamen in early cortico-striatal dysconnectivity.
Collapse
Affiliation(s)
- Eric A Nelson
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Nina V Kraguljac
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jose O Maximo
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - William Armstrong
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Adrienne C Lahti
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| |
Collapse
|
18
|
Li W, Xu J, Xiang Q, Zhuo K, Zhang Y, Liu D, Li Y. Neurometabolic and functional changes of default-mode network relate to clinical recovery in first-episode psychosis patients: A longitudinal 1H-MRS and fMRI study. Neuroimage Clin 2022; 34:102970. [PMID: 35240468 PMCID: PMC8889416 DOI: 10.1016/j.nicl.2022.102970] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 02/12/2022] [Accepted: 02/21/2022] [Indexed: 02/06/2023]
Abstract
BACKGROUND Antipsychotic treatment has improved the disrupted functional connectivity (FC) and neurometabolites levels of the default mode network (DMN) in schizophrenia patients, but a direct relationship between FC change, neurometabolic level alteration, and symptom improvement has not been built. This study examined the association between the alterations in DMN FC, the changes of neurometabolites levels in the medial prefrontal cortex (MPFC), and the improvementsinpsychopathology in a longitudinal study of drug-naïve first-episode psychosis (FEP) patients. METHODS Thirty-two drug-naïve FEP patients and 30 matched healthy controls underwent repeated assessments with the Positive and Negative Syndrome Scale (PANSS) and 3T proton magnetic resonance spectroscopy as well as resting-state functional magnetic resonance imaging. The levels of γ-aminobutyric acid, glutamate, N-acetyl-aspartate in MPFC, and the FC of DMN were measured. After 8-week antipsychotic treatment, 24 patients were re-examined. RESULTS After treatment, the changes in γ-aminobutyric acid were correlated with the alterations of FC between the MPFC and DMN, while the changes in N-acetyl-aspartate were associated with the alterations of FC between the posterior cingulate cortex/precuneus and DMN. The FC changes of both regions were correlated with patients PANSS positive score reductions. The structural equation modeling analyses revealed that the changes of DMN FC mediated the relationship between the changes of neurometabolites and the symptom improvements of the patients. CONCLUSIONS The derived neurometabolic-functional changes underlying the clinical recovery provide insights into the prognosis of FEP patients. It is noteworthy that this is an exploratory study, and future work with larger sample size is needed to validate our findings.
Collapse
Affiliation(s)
- Wenli Li
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, PR China
| | - Jiale Xu
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, PR China
| | - Qiong Xiang
- Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai 200030, PR China
| | - Kaiming Zhuo
- Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai 200030, PR China
| | - Yaoyu Zhang
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, PR China
| | - Dengtang Liu
- Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai 200030, PR China; Huashan Hospital, Fudan University, Shanghai 200040, PR China; Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai 200030, PR China; Institute of Mental Health, Fudan University, Shanghai 200030, PR China.
| | - Yao Li
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, PR China.
| |
Collapse
|
19
|
Nelson EA, Kraguljac NV, Maximo JO, Briend F, Armstrong W, Ver Hoef LW, Johnson V, Lahti AC. Hippocampal Dysconnectivity and Altered Glutamatergic Modulation of the Default Mode Network: A Combined Resting-State Connectivity and Magnetic Resonance Spectroscopy Study in Schizophrenia. BIOLOGICAL PSYCHIATRY. COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2022; 7:108-118. [PMID: 32684484 PMCID: PMC7904096 DOI: 10.1016/j.bpsc.2020.04.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/06/2020] [Accepted: 04/21/2020] [Indexed: 01/03/2023]
Abstract
BACKGROUND Converging lines of evidence point to hippocampal dysfunction in schizophrenia. It is thought that hippocampal dysfunction spreads across hippocampal subfields and to cortical regions by way of long-range efferent projections. Importantly, abnormalities in the excitation/inhibition balance could impair the long-range modulation of neural networks. The goal of this project was twofold. First, we sought to identify replicable patterns of hippocampal dysconnectivity in patients with a psychosis spectrum disorder. Second, we aimed to investigate a putative link between glutamatergic metabolism and hippocampal connectivity alterations. METHODS We evaluated resting-state hippocampal functional connectivity alterations in two cohorts of patients with a psychosis spectrum disorder. The first cohort consisted of 55 medication-naïve patients with first-episode psychosis and 41 matched healthy control subjects, and the second cohort consisted of 42 unmedicated patients with schizophrenia and 41 matched control subjects. We also acquired measurements of glutamate + glutamine in the left hippocampus using magnetic resonance spectroscopy for 42 patients with first-episode psychosis and 37 healthy control subjects from our first cohort. RESULTS We observed a pattern of hippocampal functional hypoconnectivity to regions of the default mode network and hyperconnectivity to the lateral occipital cortex in both cohorts. We also show that in healthy control subjects, greater hippocampal glutamate + glutamine levels predicted greater hippocampal functional connectivity to the anterior default mode network. Furthermore, this relationship was reversed in medication-naïve subjects with first-episode psychosis. CONCLUSIONS These results suggest that an alteration in the relationship between glutamate and functional connectivity may disrupt the dynamic of major neural networks.
Collapse
Affiliation(s)
- Eric A. Nelson
- Department of Psychology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Nina V. Kraguljac
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jose O Maximo
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Frederic Briend
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - William Armstrong
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Lawrence W. Ver Hoef
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Victoria Johnson
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Adrienne C. Lahti
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA.,Correspondence: Adrienne C. Lahti, MD, University of Alabama at Birmingham, Sparks Center, Room 501, 1720 7 Ave. S, Birmingham, Al 35233, Telephone: 205-996-6776, Fax: 205-975-4879,
| |
Collapse
|
20
|
Glutamatergic and GABAergic metabolite levels in schizophrenia-spectrum disorders: a meta-analysis of 1H-magnetic resonance spectroscopy studies. Mol Psychiatry 2022; 27:744-757. [PMID: 34584230 DOI: 10.1038/s41380-021-01297-6] [Citation(s) in RCA: 59] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 08/18/2021] [Accepted: 09/08/2021] [Indexed: 02/08/2023]
Abstract
BACKGROUND The glutamate (Glu) and gamma aminobutyric acid (GABA) hypotheses of schizophrenia were proposed in the 1980s. However, current findings on those metabolite levels in schizophrenia have been inconsistent, and the relationship between their abnormalities and the pathophysiology of schizophrenia remains unclear. To summarize the nature of the alterations of glutamatergic and GABAergic systems in schizophrenia, we conducted meta-analyses of proton magnetic resonance spectroscopy (1H-MRS) studies examining these metabolite levels. METHODS A systematic literature search was conducted using Embase, Medline, PsycINFO, and PubMed. Original studies that compared four metabolite levels (Glu, glutamine [Gln], Glx [Glu+Gln], and GABA), as measured by 1H-MRS, between individuals at high risk for psychosis, patients with first-episode psychosis, or patients with schizophrenia and healthy controls (HC) were included. A random-effects model was used to calculate the effect sizes for group differences in these metabolite levels of 18 regions of interest between the whole group or schizophrenia group and HC. Subgroup analysis and meta-regression were performed based on the status of antipsychotic treatment, illness stage, treatment resistance, and magnetic field strength. RESULTS One-hundred-thirty-four studies met the eligibility criteria, totaling 7993 participants with SZ-spectrum disorders and 8744 HC. 14 out of 18 ROIs had enough numbers of studies to examine the group difference in the metabolite levels. In the whole group, Glx levels in the basal ganglia (g = 0.32; 95% CIs: 0.18-0.45) were elevated. Subgroup analyses showed elevated Glx levels in the hippocampus (g = 0.47; 95% CIs: 0.21-0.73) and dorsolateral prefrontal cortex (g = 0.25; 95% CIs: 0.05-0.44) in unmedicated patients than HC. GABA levels in the MCC were decreased in the first-episode psychosis group compared with HC (g = -0.40; 95% CIs: -0.62 to -0.17). Treatment-resistant schizophrenia (TRS) group had elevated Glx and Glu levels in the MCC (Glx: g = 0.7; 95% CIs: 0.38-1.01; Glu: g = 0.63; 95% CIs: 0.31-0.94) while MCC Glu levels were decreased in the patient group except TRS (g = -0.17; 95% CIs: -0.33 to -0.01). CONCLUSIONS Increased glutamatergic metabolite levels and reduced GABA levels indicate that the disruption of excitatory/inhibitory balance may be related to the pathophysiology of schizophrenia-spectrum disorders.
Collapse
|
21
|
Frontal neural metabolite changes in schizophrenia and their association with cognitive control: A systematic review. Neurosci Biobehav Rev 2021; 132:224-247. [PMID: 34864431 PMCID: PMC8830497 DOI: 10.1016/j.neubiorev.2021.11.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 11/05/2021] [Accepted: 11/09/2021] [Indexed: 01/01/2023]
Abstract
GABA levels are decreased in medial frontal brain areas of schizophrenia patients. Glutamate levels are lower in medial and lateral frontal areas in chronic patients. Working memory performance is associated with frontal GABA and Glu. Prediction errors are associated Glu and medial frontal GABA. Processing speed correlates with medial frontal GABA levels.
A large proportion of patients with schizophrenia exhibit deficits in cognitive control functions including working memory, processing speed and inhibitory control, which have been associated with frontal brain areas. In this systematic review, we investigated differences between chronic schizophrenia patients, first-episode (FEP) patients and healthy control groups in the neurometabolite levels of GABA, glutamate, glutamine and Glx in frontal brain areas. Additionally, we reviewed correlations between cognitive control functions or negative symptoms and these neurometabolite levels. Several studies reported decreased GABA or glutamate concentrations in frontal lobe areas, particularly in chronic schizophrenia patients, while the results were mixed for FEP patients. Working memory performance and prediction errors have been associated with frontal GABA and glutamate levels, and processing speed with frontomedial GABA levels in chronic patients. The relationship between metabolites and negative symptom severity was somewhat inconsistent. Future studies should take the participants' age, medication status or responsivity, disease stage and precise anatomical location of the voxel into account when comparing neurometabolite levels between schizophrenia patients and healthy controls.
Collapse
|
22
|
Jeon P, Limongi R, Ford SD, Mackinley M, Dempster K, Théberge J, Palaniyappan L. Progressive Changes in Glutamate Concentration in Early Stages of Schizophrenia: A Longitudinal 7-Tesla MRS Study. ACTA ACUST UNITED AC 2021; 2:sgaa072. [PMID: 34746793 PMCID: PMC8561748 DOI: 10.1093/schizbullopen/sgaa072] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Progressive reduction in glutamatergic transmission has been proposed as an important component of the illness trajectory of schizophrenia. Despite its popularity, to date, this notion has not been convincingly tested in patients in early stages of schizophrenia. In a longitudinal 7T magnetic resonance spectroscopy (1H-MRS), we quantified glutamate at the dorsal anterior cingulate cortex in 21 participants with a median lifetime antipsychotic exposure of less than 3 days and followed them up after 6 months of treatment. Ten healthy controls were also scanned at 2 time points. While patients had significantly lower overall glutamate levels than healthy controls (F(1,27) = 5.23, P = .03), we did not observe a progressive change of glutamate concentration in patients (F(1,18) = 0.47, P = .50), and the group by time interaction was not significant (F(1,27) = 0.86, P = .36). On average, patients with early psychosis receiving treatment showed a 0.02 mM/y increase, while healthy controls showed a 0.06 mM/y reduction of MRS glutamate levels. Bayesian analysis of our observations does not support early, post-onset glutamate loss in schizophrenia. Interestingly, it provides evidence in favor of a lack of progressive glutamate change in our schizophrenia sample—indicating that the glutamate level at the onset of illness was the best predictor of the levels 6 months after treatment. A more nuanced view of glutamatergic physiology, linked to early cortical maturation, may be required to understand glutamate-mediated dynamics in schizophrenia.
Collapse
Affiliation(s)
- Peter Jeon
- Department of Medical Biophysics, Western University, London, Ontario, Canada.,Lawson Health Research Institute, Imaging Division, London, Ontario, Canada
| | - Roberto Limongi
- Robarts Research Institute, Western University, London, Ontario, Canada
| | - Sabrina D Ford
- Department of Psychiatry, Western University, London, Ontario, Canada
| | - Michael Mackinley
- Department of Neuroscience, Western University, London, Ontario, Canada
| | - Kara Dempster
- Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Jean Théberge
- Department of Medical Biophysics, Western University, London, Ontario, Canada.,Lawson Health Research Institute, Imaging Division, London, Ontario, Canada.,St. Joseph's Health Care, Diagnostic Imaging, London, Ontario, Canada.,Department of Medical Imaging, Western University, London, Ontario, Canada
| | - Lena Palaniyappan
- Department of Medical Biophysics, Western University, London, Ontario, Canada.,Robarts Research Institute, Western University, London, Ontario, Canada.,Department of Psychiatry, Western University, London, Ontario, Canada
| |
Collapse
|
23
|
Overbeek G, Gawne TJ, Reid MA, Kraguljac NV, Lahti AC. A multimodal neuroimaging study investigating resting-state connectivity, glutamate and GABA at 7 T in first-episode psychosis. J Psychiatry Neurosci 2021; 46:E702-E710. [PMID: 34933941 PMCID: PMC8695527 DOI: 10.1503/jpn.210107] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 10/05/2021] [Accepted: 10/18/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The major excitatory and inhibitory neurometabolites in the brain, glutamate and γ-aminobutyric acid (GABA), respectively, are related to the functional MRI signal. Disruption of resting-state functional MRI signals has been reported in psychosis spectrum disorders, but few studies have investigated the role of these metabolites in this context. METHODS We included 19 patients with first-episode psychosis and 21 healthy controls in this combined magnetic resonance spectroscopy (MRS) and resting-state functional connectivity study. All imaging was performed on a Siemens Magnetom 7 T MRI scanner. Both the MRS voxel and the seed for functional connectivity analysis were located in the dorsal anterior cingulate cortex (ACC). We used multiple regressions to test for an interaction between ACC brain connectivity, diagnosis and neurometabolites. RESULTS ACC brain connectivity was altered in first-episode psychosis. The relationship between ACC glutamate and ACC functional connectivity differed between patients with first-episode psychosis and healthy controls in the precuneus, retrosplenial cortex, supramarginal gyrus and angular gyrus. As well, the relationship between ACC GABA and ACC functional connectivity differed between groups in the caudate, putamen and supramarginal gyrus. LIMITATIONS We used a small sample size. As well, although they were not chronically medicated, all participants were medicated during the study. CONCLUSION We demonstrated a link between the major excitatory and inhibitory brain metabolites and resting-state functional connectivity in healthy participants, as well as an alteration in this relationship in patients with first-episode psychosis. Combining data from different imaging modalities may help our mechanistic understanding of the relationship between major neurometabolites and brain network dynamics, and shed light on the pathophysiology of first-episode psychosis.
Collapse
Affiliation(s)
- Gregory Overbeek
- From the Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham (Overbeek, Kraguljac, Lahti); the Department of Optometry and Vision Science, University of Alabama at Birmingham (Gawne); and the Department of Electrical and Computer Engineering, Auburn University, Auburn AL (Reid)
| | - Timothy J Gawne
- From the Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham (Overbeek, Kraguljac, Lahti); the Department of Optometry and Vision Science, University of Alabama at Birmingham (Gawne); and the Department of Electrical and Computer Engineering, Auburn University, Auburn AL (Reid)
| | - Meredith A Reid
- From the Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham (Overbeek, Kraguljac, Lahti); the Department of Optometry and Vision Science, University of Alabama at Birmingham (Gawne); and the Department of Electrical and Computer Engineering, Auburn University, Auburn AL (Reid)
| | - Nina V Kraguljac
- From the Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham (Overbeek, Kraguljac, Lahti); the Department of Optometry and Vision Science, University of Alabama at Birmingham (Gawne); and the Department of Electrical and Computer Engineering, Auburn University, Auburn AL (Reid)
| | - Adrienne C Lahti
- From the Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham (Overbeek, Kraguljac, Lahti); the Department of Optometry and Vision Science, University of Alabama at Birmingham (Gawne); and the Department of Electrical and Computer Engineering, Auburn University, Auburn AL (Reid)
| |
Collapse
|
24
|
Maximo JO, Briend F, Armstrong WP, Kraguljac NV, Lahti AC. Salience network glutamate and brain connectivity in medication-naïve first episode patients - A multimodal magnetic resonance spectroscopy and resting state functional connectivity MRI study. Neuroimage Clin 2021; 32:102845. [PMID: 34662778 PMCID: PMC8526757 DOI: 10.1016/j.nicl.2021.102845] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 09/08/2021] [Accepted: 09/25/2021] [Indexed: 11/25/2022]
Abstract
BACKGROUND Salience network (SN) connectivity is altered in schizophrenia, but the pathophysiological origin remains poorly understood. The goal of this multimodal neuroimaging study was to investigate the role of glutamatergic metabolism as putative mechanism underlying SN dysconnectivity in first episode psychosis (FEP) subjects. METHODS We measured glutamate + glutamine (Glx) in the dorsal anterior cingulate cortex (dACC) from 70 antipsychotic-naïve FEP subjects and 52 healthy controls (HC). The dACC was then used as seed to define positive and negative resting state functional connectivity (FC) of the SN. We used multiple regression analyses to test main effects and group interactions of Glx and FC associations. RESULTS dACC Glx levels did not differ between groups. Positive FC was significantly reduced in FEP compared to HC, and no group differences were found in negative FC. Group interactions of Glx-FC associations were found within the SN for positive FC, and in parietal cortices for negative FC. In HC, higher Glx levels predicted greater positive FC in the dACC and insula, and greater negative FC of the lateral parietal cortex. These relationships were weaker or absent in FEP. CONCLUSIONS Here, we found that positive FC in the SN is already altered in medication-naïve FEP, underscoring the importance of considering both correlations and anticorrelations for characterization of pathology. Our data demonstrate that Glx and functional connectivity work differently in FEP than in HC, pointing to a possible mechanism underlying dysconnectivity in psychosis.
Collapse
Affiliation(s)
- Jose O Maximo
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Frederic Briend
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA; UMR1253, iBrain, Université de Tours, Inserm, Tours, France
| | - William P Armstrong
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Nina V Kraguljac
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Adrienne C Lahti
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA.
| |
Collapse
|
25
|
Kraguljac NV, Lahti AC. Neuroimaging as a Window Into the Pathophysiological Mechanisms of Schizophrenia. Front Psychiatry 2021; 12:613764. [PMID: 33776813 PMCID: PMC7991588 DOI: 10.3389/fpsyt.2021.613764] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 02/15/2021] [Indexed: 12/16/2022] Open
Abstract
Schizophrenia is a complex neuropsychiatric disorder with a diverse clinical phenotype that has a substantial personal and public health burden. To advance the mechanistic understanding of the illness, neuroimaging can be utilized to capture different aspects of brain pathology in vivo, including brain structural integrity deficits, functional dysconnectivity, and altered neurotransmitter systems. In this review, we consider a number of key scientific questions relevant in the context of neuroimaging studies aimed at unraveling the pathophysiology of schizophrenia and take the opportunity to reflect on our progress toward advancing the mechanistic understanding of the illness. Our data is congruent with the idea that the brain is fundamentally affected in the illness, where widespread structural gray and white matter involvement, functionally abnormal cortical and subcortical information processing, and neurometabolic dysregulation are present in patients. Importantly, certain brain circuits appear preferentially affected and subtle abnormalities are already evident in first episode psychosis patients. We also demonstrated that brain circuitry alterations are clinically relevant by showing that these pathological signatures can be leveraged for predicting subsequent response to antipsychotic treatment. Interestingly, dopamine D2 receptor blockers alleviate neural abnormalities to some extent. Taken together, it is highly unlikely that the pathogenesis of schizophrenia is uniform, it is more plausible that there may be multiple different etiologies that converge to the behavioral phenotype of schizophrenia. Our data underscore that mechanistically oriented neuroimaging studies must take non-specific factors such as antipsychotic drug exposure or illness chronicity into consideration when interpreting disease signatures, as a clear characterization of primary pathophysiological processes is an imperative prerequisite for rational drug development and for alleviating disease burden in our patients.
Collapse
Affiliation(s)
- Nina Vanessa Kraguljac
- Neuroimaging and Translational Research Laboratory, Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Adrienne Carol Lahti
- Neuroimaging and Translational Research Laboratory, Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, United States
| |
Collapse
|
26
|
Kiemes A, Davies C, Kempton MJ, Lukow PB, Bennallick C, Stone JM, Modinos G. GABA, Glutamate and Neural Activity: A Systematic Review With Meta-Analysis of Multimodal 1H-MRS-fMRI Studies. Front Psychiatry 2021; 12:644315. [PMID: 33762983 PMCID: PMC7982484 DOI: 10.3389/fpsyt.2021.644315] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 02/15/2021] [Indexed: 12/11/2022] Open
Abstract
Multimodal neuroimaging studies combining proton magnetic resonance spectroscopy (1H-MRS) to quantify GABA and/or glutamate concentrations and functional magnetic resonance imaging (fMRI) to measure brain activity non-invasively have advanced understanding of how neurochemistry and neurophysiology may be related at a macroscopic level. The present study aimed to perform a systematic review and meta-analysis of available studies examining the relationship between 1H-MRS glutamate and/or GABA levels and task-related fMRI signal in the healthy brain. Ovid (Medline, Embase, and PsycINFO) and Pubmed databases were systematically searched to identify articles published until December 2019. The primary outcome of interest was the association between resting levels of glutamate or GABA and task-related fMRI. Fifty-five papers were identified for inclusion in the systematic review. A further 22 studies were entered into four separate meta-analyses. These meta-analyses found evidence of significant negative associations between local GABA levels and (a) fMRI activation to visual tasks in the occipital lobe, and (b) activation to emotion processing in the medial prefrontal cortex (mPFC)/anterior cingulate cortex (ACC). However, there was no significant association between mPFC/ACC glutamate levels and fMRI activation to cognitive control tasks or to emotional processing, with the relationship to emotion processing related neural activity narrowly missing significance. Moreover, our systematic review also found converging evidence of negative associations between GABA levels and local brain activity, and positive associations between glutamate levels and distal brain activity, outside of the 1H-MRS sampling region. Albeit less consistently, additional relationships between GABA levels and distal brain activity and between glutamate levels and local brain activity were found. It remains unclear if the absence of effects for other brain regions and other cognitive-emotional domains reflects study heterogeneity or potential confounding effects of age, sex, or other unknown factors. Advances in 1H-MRS methodology as well as in the integration of 1H-MRS readouts with other imaging modalities for indexing neural activity hold great potential to reveal key aspects of the pathophysiology of mental health disorders involving aberrant interactions between neurochemistry and neurophysiology such as schizophrenia.
Collapse
Affiliation(s)
- Amanda Kiemes
- Psychosis Studies Department, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Cathy Davies
- Psychosis Studies Department, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Matthew J Kempton
- Psychosis Studies Department, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.,Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Paulina B Lukow
- Psychosis Studies Department, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Carly Bennallick
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - James M Stone
- Brighton and Sussex Medical School, University of Sussex & University of Brighton, Brighton, United Kingdom
| | - Gemma Modinos
- Psychosis Studies Department, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.,Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.,Medical Research Centre Centre for Neurodevelopmental Disorders, King's College London, London, United Kingdom
| |
Collapse
|
27
|
Zhang YD, Dong Z, Wang SH, Yu X, Yao X, Zhou Q, Hu H, Li M, Jiménez-Mesa C, Ramirez J, Martinez FJ, Gorriz JM. Advances in multimodal data fusion in neuroimaging: Overview, challenges, and novel orientation. AN INTERNATIONAL JOURNAL ON INFORMATION FUSION 2020; 64:149-187. [PMID: 32834795 PMCID: PMC7366126 DOI: 10.1016/j.inffus.2020.07.006] [Citation(s) in RCA: 121] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/06/2020] [Accepted: 07/14/2020] [Indexed: 05/13/2023]
Abstract
Multimodal fusion in neuroimaging combines data from multiple imaging modalities to overcome the fundamental limitations of individual modalities. Neuroimaging fusion can achieve higher temporal and spatial resolution, enhance contrast, correct imaging distortions, and bridge physiological and cognitive information. In this study, we analyzed over 450 references from PubMed, Google Scholar, IEEE, ScienceDirect, Web of Science, and various sources published from 1978 to 2020. We provide a review that encompasses (1) an overview of current challenges in multimodal fusion (2) the current medical applications of fusion for specific neurological diseases, (3) strengths and limitations of available imaging modalities, (4) fundamental fusion rules, (5) fusion quality assessment methods, and (6) the applications of fusion for atlas-based segmentation and quantification. Overall, multimodal fusion shows significant benefits in clinical diagnosis and neuroscience research. Widespread education and further research amongst engineers, researchers and clinicians will benefit the field of multimodal neuroimaging.
Collapse
Affiliation(s)
- Yu-Dong Zhang
- School of Informatics, University of Leicester, Leicester, LE1 7RH, Leicestershire, UK
- Department of Information Systems, Faculty of Computing and Information Technology, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Zhengchao Dong
- Department of Psychiatry, Columbia University, USA
- New York State Psychiatric Institute, New York, NY 10032, USA
| | - Shui-Hua Wang
- Department of Information Systems, Faculty of Computing and Information Technology, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- School of Architecture Building and Civil engineering, Loughborough University, Loughborough, LE11 3TU, UK
- School of Mathematics and Actuarial Science, University of Leicester, LE1 7RH, UK
| | - Xiang Yu
- School of Informatics, University of Leicester, Leicester, LE1 7RH, Leicestershire, UK
| | - Xujing Yao
- School of Informatics, University of Leicester, Leicester, LE1 7RH, Leicestershire, UK
| | - Qinghua Zhou
- School of Informatics, University of Leicester, Leicester, LE1 7RH, Leicestershire, UK
| | - Hua Hu
- Department of Psychiatry, Columbia University, USA
- Department of Neurology, The Second Affiliated Hospital of Soochow University, China
| | - Min Li
- Department of Psychiatry, Columbia University, USA
- School of Internet of Things, Hohai University, Changzhou, China
| | - Carmen Jiménez-Mesa
- Department of Signal Theory, Networking and Communications, University of Granada, Granada, Spain
| | - Javier Ramirez
- Department of Signal Theory, Networking and Communications, University of Granada, Granada, Spain
| | - Francisco J Martinez
- Department of Signal Theory, Networking and Communications, University of Granada, Granada, Spain
| | - Juan Manuel Gorriz
- Department of Signal Theory, Networking and Communications, University of Granada, Granada, Spain
- Department of Psychiatry, University of Cambridge, Cambridge CB21TN, UK
| |
Collapse
|
28
|
Neuromodulation in Schizophrenia: Relevance of Neuroimaging. Curr Behav Neurosci Rep 2020. [DOI: 10.1007/s40473-020-00209-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
29
|
Bryant JE, Frölich M, Tran S, Reid MA, Lahti AC, Kraguljac NV. Ketamine induced changes in regional cerebral blood flow, interregional connectivity patterns, and glutamate metabolism. J Psychiatr Res 2019; 117:108-115. [PMID: 31376621 PMCID: PMC7291620 DOI: 10.1016/j.jpsychires.2019.07.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 06/19/2019] [Accepted: 07/26/2019] [Indexed: 12/31/2022]
Abstract
Several imaging studies have attempted to characterize the contribution of glutamatergic dysfunction to functional dysconnectivity of large-scale brain networks using ketamine models. However, findings from BOLD imaging studies are conflicting, in part because the signal stems from a complex interaction between blood flow, blood volume, and oxygen consumption. We used arterial spin labelling imaging to measure regional cerebral blood flow (rCBF) in a group of healthy volunteers during a saline and during a ketamine infusion. We examined changes in rCBF and interregional connectivity patterns, as well as their associations with clinical symptom severity and Glx (glutamate + glutamine) assessed with magnetic resonance spectroscopy. We report a regionally selective pattern of rCBF changes following ketamine administration and complex changes in interregional connectivity patterns. We also found that the increase in rCBF in the bilateral putamen and left hippocampus was positively correlated with ketamine induced clinical symptom severity while anterior cingulate rCBF during the ketamine challenge was negatively correlated with change in hippocampal Glx. Our study adds to the efforts to empirically confirm putative links between an NMDA receptor blockage and dysconnectivity of large-scale brain networks, specifically the salience, executive control and default mode networks, suggesting that a glutamatergic imbalance may contribute to dysconnectivity. Development of glutamatergic compounds that alleviate disease burden, possibly through normalizing glutamate excess related increased rCBF, is direly needed.
Collapse
Affiliation(s)
- James Edward Bryant
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, United States
| | - Michael Frölich
- Department of Anesthesiology, University of Alabama at Birmingham, United States
| | - Steve Tran
- Department of Anesthesiology, University of Alabama at Birmingham, United States
| | - Meredith Amanda Reid
- MRI Research Center, Department of Electrical and Computer Engineering, Auburn University, United States
| | - Adrienne Carol Lahti
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, United States
| | - Nina Vanessa Kraguljac
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, United States.
| |
Collapse
|
30
|
Longitudinal studies of functional magnetic resonance imaging in first-episode psychosis: A systematic review. Eur Psychiatry 2019; 59:60-69. [PMID: 31075523 DOI: 10.1016/j.eurpsy.2019.04.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 04/27/2019] [Accepted: 04/28/2019] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Little is known about changes in brain functioning after first-episode psychosis (FEP). Such knowledge is important for predicting the course of disease and adapting interventions. Functional magnetic resonance imaging has become a promising tool for exploring brain function at the time of symptom onset and at follow-up. METHOD A systematic review of longitudinal fMRI studies with FEP patients according to PRISMA guidelines. Resting-state and task-activated studies were considered together. RESULTS Eleven studies were included. These reported on a total of 236 FEP patients were evaluated by two fMRI scans and clinical assessments. Five studies found hypoactivation at baseline in prefrontal cortex areas, two studies found hypoactivation in the amygdala and hippocampus, and three others found hypoactivation in the basal ganglia. Other hypoactivated areas were the anterior cingulate cortex, thalamus and posterior cingulate cortex. Ten out of eleven studies reported (partial) normalization by increased activation after antipsychotic treatment. A minority of studies observed hyperactivation at baseline. CONCLUSIONS This review of longitudinal FEP samples studies reveals a pattern of predominantly hypoactivation in several brain areas at baseline that may normalize to a certain extent after treatment. The results should be interpreted with caution given the small number of studies and their methodological and clinical heterogeneity.
Collapse
|
31
|
Extrinsic and default mode networks in psychiatric conditions: Relationship to excitatory-inhibitory transmitter balance and early trauma. Neurosci Biobehav Rev 2019; 99:90-100. [PMID: 30769024 DOI: 10.1016/j.neubiorev.2019.02.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 01/30/2019] [Accepted: 02/07/2019] [Indexed: 02/08/2023]
Abstract
Over the last three decades there has been an accumulation of Magnetic Resonance Imaging (MRI) studies reporting that aberrant functional networks may underlie cognitive deficits and other symptoms across a range of psychiatric diagnoses. The use of pharmacological MRI and 1H-Magnetic Resonance Spectroscopy (1H-MRS) has allowed researchers to investigate how changes in network dynamics are related to perturbed excitatory and inhibitory neurotransmission in individuals with psychiatric conditions. More recently, changes in functional network dynamics and excitatory/inhibitory (E/I) neurotransmission have been linked to early childhood trauma, a major antecedents for psychiatric illness in adulthood. Here we review studies investigating whether perturbed network dynamics seen across psychiatric conditions are related to changes in E/I neurotransmission, and whether such changes could be linked to childhood trauma. Whilst there is currently a paucity of studies relating early traumatic experiences to altered E/I balance and network function, the research discussed here lead towards a plausible mechanistic hypothesis, linking early traumatic experiences to cognitive dysfunction and symptoms mediated by E/I neurotransmitter imbalances.
Collapse
|