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Kaptan M, Pfyffer D, Konstantopoulos CG, Law CS, Weber II KA, Glover GH, Mackey S. Recent developments and future avenues for human corticospinal neuroimaging. Front Hum Neurosci 2024; 18:1339881. [PMID: 38332933 PMCID: PMC10850311 DOI: 10.3389/fnhum.2024.1339881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 01/09/2024] [Indexed: 02/10/2024] Open
Abstract
Non-invasive neuroimaging serves as a valuable tool for investigating the mechanisms within the central nervous system (CNS) related to somatosensory and motor processing, emotions, memory, cognition, and other functions. Despite the extensive use of brain imaging, spinal cord imaging has received relatively less attention, regardless of its potential to study peripheral communications with the brain and the descending corticospinal systems. To comprehensively understand the neural mechanisms underlying human sensory and motor functions, particularly in pathological conditions, simultaneous examination of neuronal activity in both the brain and spinal cord becomes imperative. Although technically demanding in terms of data acquisition and analysis, a growing but limited number of studies have successfully utilized specialized acquisition protocols for corticospinal imaging. These studies have effectively assessed sensorimotor, autonomic, and interneuronal signaling within the spinal cord, revealing interactions with cortical processes in the brain. In this mini-review, we aim to examine the expanding body of literature that employs cutting-edge corticospinal imaging to investigate the flow of sensorimotor information between the brain and spinal cord. Additionally, we will provide a concise overview of recent advancements in functional magnetic resonance imaging (fMRI) techniques. Furthermore, we will discuss potential future perspectives aimed at enhancing our comprehension of large-scale neuronal networks in the CNS and their disruptions in clinical disorders. This collective knowledge will aid in refining combined corticospinal fMRI methodologies, leading to the development of clinically relevant biomarkers for conditions affecting sensorimotor processing in the CNS.
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Affiliation(s)
- Merve Kaptan
- Division of Pain Medicine, Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Palo Alto, CA, United States
| | - Dario Pfyffer
- Division of Pain Medicine, Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Palo Alto, CA, United States
| | - Christiane G. Konstantopoulos
- Division of Pain Medicine, Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Palo Alto, CA, United States
| | - Christine S.W. Law
- Division of Pain Medicine, Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Palo Alto, CA, United States
| | - Kenneth A. Weber II
- Division of Pain Medicine, Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Palo Alto, CA, United States
| | - Gary H. Glover
- Radiological Sciences Laboratory, Department of Radiology, Stanford University School of Medicine, Palo Alto, CA, United States
| | - Sean Mackey
- Division of Pain Medicine, Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Palo Alto, CA, United States
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Haynes G, Muhammad F, Khan AF, Mohammadi E, Smith ZA, Ding L. The current state of spinal cord functional magnetic resonance imaging and its application in clinical research. J Neuroimaging 2023; 33:877-888. [PMID: 37740582 DOI: 10.1111/jon.13158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 09/05/2023] [Accepted: 09/11/2023] [Indexed: 09/24/2023] Open
Abstract
Since its development, spinal cord functional magnetic resonance imaging (fMRI) has utilized various methodologies and stimulation protocols to develop a deeper understanding of a healthy human spinal cord that lays a foundation for its use in clinical research and practice. In this review, we conducted a comprehensive literature search on spinal cord fMRI studies and summarized the recent advancements and resulting scientific achievements of spinal cord fMRI in the following three aspects: the current state of spinal cord fMRI methodologies and stimulation protocols, knowledge about the healthy spinal cord's functions obtained via spinal cord fMRI, and fMRI's exemplary usage in spinal cord diseases and injuries. We conclude with a discussion that, while technical challenges exist, novel fMRI technologies for and new knowledge about the healthy human spinal cord have been established. Empowered by these developments, investigations of pathological and injury states within the spinal cord have become the next important direction of spinal cord fMRI. Recent clinical investigations into spinal cord pathologies, for example, fibromyalgia, multiple sclerosis, spinal cord injury, and cervical spondylotic myelopathy, have already provided deep insights into spinal cord impairments and the time course of impairment-caused changes. We expect that future spinal cord fMRI advancement and research development will further enhance our understanding of various spinal cord diseases and provide the foundation for evaluating existing and developing new treatment plans.
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Affiliation(s)
- Grace Haynes
- Stephenson School of Biomedical Engineering, University of Oklahoma, Norman, Oklahoma, USA
| | - Fauziyya Muhammad
- Department of Neurosurgery, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Ali F Khan
- Department of Neurosurgery, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Esmaeil Mohammadi
- Department of Neurosurgery, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Zachary A Smith
- Department of Neurosurgery, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Lei Ding
- Stephenson School of Biomedical Engineering, University of Oklahoma, Norman, Oklahoma, USA
- Institute for Biomedical Engineering, Science, and Technology, University of Oklahoma, Norman, Oklahoma, USA
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Ioachim G, Warren HJM, Powers JM, Staud R, Pukall CF, Stroman PW. Distinct neural signaling characteristics between fibromyalgia and provoked vestibulodynia revealed by means of functional magnetic resonance imaging in the brainstem and spinal cord. FRONTIERS IN PAIN RESEARCH 2023; 4:1171160. [PMID: 37283704 PMCID: PMC10240076 DOI: 10.3389/fpain.2023.1171160] [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: 02/21/2023] [Accepted: 04/27/2023] [Indexed: 06/08/2023] Open
Abstract
Introduction Fibromyalgia and provoked vestibulodynia are two chronic pain conditions that disproportionately affect women. The mechanisms underlying the pain in these conditions are still poorly understood, but there is speculation that both may be linked to altered central sensitization and autonomic regulation. Neuroimaging studies of these conditions focusing on the brainstem and spinal cord to explore changes in pain regulation and autonomic regulation are emerging, but none to date have directly compared pain and autonomic regulation in these conditions. This study compares groups of women with fibromyalgia and provoked vestibulodynia to healthy controls using a threat/safety paradigm with a predictable noxious heat stimulus. Methods Functional magnetic resonance imaging data were acquired at 3 tesla in the cervical spinal cord and brainstem with previously established methods. Imaging data were analyzed with structural equation modeling and ANCOVA methods during: a period of noxious stimulation, and a period before the stimulation when participants were expecting the upcoming pain. Results The results demonstrate several similarities and differences between brainstem/spinal cord connectivity related to autonomic and pain regulatory networks across the three groups in both time periods. Discussion Based on the regions and connections involved in the differences, the altered pain processing in fibromyalgia appears to be related to changes in how autonomic and pain regulation networks are integrated, whereas altered pain processing in provoked vestibulodynia is linked in part to changes in arousal or salience networks as well as changes in affective components of pain regulation.
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Affiliation(s)
- Gabriela Ioachim
- Center for Neuroscience Studies, Queen’s University, Kingston, ON, Canada
| | | | - Jocelyn M. Powers
- Center for Neuroscience Studies, Queen’s University, Kingston, ON, Canada
| | - Roland Staud
- Department of Medicine, University of Florida, Gainseville, FL, United States
| | - Caroline F. Pukall
- Center for Neuroscience Studies, Queen’s University, Kingston, ON, Canada
- Department of Psychology, Queen’s University, Kingston, ON, Canada
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, ON, Canada
| | - Patrick W. Stroman
- Center for Neuroscience Studies, Queen’s University, Kingston, ON, Canada
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, ON, Canada
- Department of Physics, Queen's University, Kingston, ON, Canada
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Kaptan M, Horn U, Vannesjo SJ, Mildner T, Weiskopf N, Finsterbusch J, Brooks JCW, Eippert F. Reliability of resting-state functional connectivity in the human spinal cord: assessing the impact of distinct noise sources. Neuroimage 2023; 275:120152. [PMID: 37142169 DOI: 10.1016/j.neuroimage.2023.120152] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Revised: 04/20/2023] [Accepted: 05/01/2023] [Indexed: 05/06/2023] Open
Abstract
The investigation of spontaneous fluctuations of the blood-oxygen-level-dependent (BOLD) signal has recently been extended from the brain to the spinal cord, where it has stimulated interest from a clinical perspective. A number of resting-state functional magnetic resonance imaging (fMRI) studies have demonstrated robust functional connectivity between the time series of BOLD fluctuations in bilateral dorsal horns and between those in bilateral ventral horns, in line with the functional neuroanatomy of the spinal cord. A necessary step prior to extension to clinical studies is assessing the reliability of such resting-state signals, which we aimed to do here in a group of 45 healthy young adults at the clinically prevalent field strength of 3T. When investigating connectivity in the entire cervical spinal cord, we observed fair to good reliability for dorsal-dorsal and ventral-ventral connectivity, whereas reliability was poor for within- and between-hemicord dorsal-ventral connectivity. Considering how prone spinal cord fMRI is to noise, we extensively investigated the impact of distinct noise sources and made two crucial observations: removal of physiological noise led to a reduction in functional connectivity strength and reliability - due to the removal of stable and participant-specific noise patterns - whereas removal of thermal noise considerably increased the detectability of functional connectivity without a clear influence on reliability. Finally, we also assessed connectivity within spinal cord segments and observed that while the pattern of connectivity was similar to that of whole cervical cord, reliability at the level of single segments was consistently poor. Taken together, our results demonstrate the presence of reliable resting-state functional connectivity in the human spinal cord even after thoroughly accounting for physiological and thermal noise, but at the same time urge caution if focal changes in connectivity (e.g. due to segmental lesions) are to be studied, especially in a longitudinal manner.
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Affiliation(s)
- Merve Kaptan
- Max Planck Research Group Pain Perception, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
| | - Ulrike Horn
- Max Planck Research Group Pain Perception, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - S Johanna Vannesjo
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Toralf Mildner
- Methods & Development Group Nuclear Magnetic Resonance, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Nikolaus Weiskopf
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; Felix Bloch Institute for Solid State Physics, Faculty of Physics and Earth Sciences, University of Leipzig, Leipzig, Germany
| | - Jürgen Finsterbusch
- Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jonathan C W Brooks
- School of Psychology, University of East Anglia Wellcome Wolfson Brain Imaging Centre (UWWBIC), Norwich, United Kingdom
| | - Falk Eippert
- Max Planck Research Group Pain Perception, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
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Hoggarth MA, Wang MC, Hemmerling KJ, Vigotsky AD, Smith ZA, Parrish TB, Weber KA, Bright MG. Effects of variability in manually contoured spinal cord masks on fMRI co-registration and interpretation. Front Neurol 2022; 13:907581. [PMID: 36341092 PMCID: PMC9630922 DOI: 10.3389/fneur.2022.907581] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 09/26/2022] [Indexed: 02/01/2023] Open
Abstract
Functional magnetic resonance imaging (fMRI) of the human spinal cord (SC) is a unique non-invasive method for characterizing neurovascular responses to stimuli. Group-analysis of SC fMRI data involves co-registration of subject-level data to standard space, which requires manual masking of the cord and may result in bias of group-level SC fMRI results. To test this, we examined variability in SC masks drawn in fMRI data from 21 healthy participants from a completed study mapping responses to sensory stimuli of the C7 dermatome. Masks were drawn on temporal mean functional image by eight raters with varying levels of neuroimaging experience, and the rater from the original study acted as a reference. Spatial agreement between rater and reference masks was measured using the Dice Similarity Coefficient, and the influence of rater and dataset was examined using ANOVA. Each rater's masks were used to register functional data to the PAM50 template. Gray matter-white matter signal contrast of registered functional data was used to evaluate the spatial normalization accuracy across raters. Subject- and group-level analyses of activation during left- and right-sided sensory stimuli were performed for each rater's co-registered data. Agreement with the reference SC mask was associated with both rater (F(7, 140) = 32.12, P < 2 × 10-16, η2 = 0.29) and dataset (F(20, 140) = 20.58, P < 2 × 10-16, η2 = 0.53). Dataset variations may reflect image quality metrics: the ratio between the signal intensity of spinal cord voxels and surrounding cerebrospinal fluid was correlated with DSC results (p < 0.001). As predicted, variability in the manually-drawn masks influenced spatial normalization, and GM:WM contrast in the registered data showed significant effects of rater and dataset (rater: F(8, 160) = 23.57, P < 2 × 10-16, η2 = 0.24; dataset: F(20, 160) = 22.00, P < 2 × 10-16, η2 = 0.56). Registration differences propagated into subject-level activation maps which showed rater-dependent agreement with the reference. Although group-level activation maps differed between raters, no systematic bias was identified. Increasing consistency in manual contouring of spinal cord fMRI data improved co-registration and inter-rater agreement in activation mapping, however our results suggest that improvements in image acquisition and post-processing are also critical to address.
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Affiliation(s)
- Mark A. Hoggarth
- Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Max C. Wang
- Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL, United States
| | - Kimberly J. Hemmerling
- Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
- Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL, United States
| | - Andrew D. Vigotsky
- Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL, United States
- Department of Statistics, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL, United States
| | - Zachary A. Smith
- Department of Neurological Surgery, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Todd B. Parrish
- Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL, United States
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Kenneth A. Weber
- Systems Neuroscience and Pain Lab, Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University, Palo Alto, CA, United States
| | - Molly G. Bright
- Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
- Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL, United States
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Powers JM, Ioachim G, Stroman PW. Music to My Senses: Functional Magnetic Resonance Imaging Evidence of Music Analgesia Across Connectivity Networks Spanning the Brain and Brainstem. FRONTIERS IN PAIN RESEARCH 2022; 3:878258. [PMID: 35663249 PMCID: PMC9160574 DOI: 10.3389/fpain.2022.878258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 04/29/2022] [Indexed: 11/13/2022] Open
Abstract
Pain is often viewed and studied as an isolated perception. However, cognition, emotion, salience effects, and autonomic and sensory input are all integrated to create a comprehensive experience. Music-induced analgesia has been used for thousands of years, with moderate behavioural effects on pain perception, yet the neural mechanisms remain ambiguous. The purpose of this study was to investigate the effects of music analgesia through individual ratings of pain, and changes in connectivity across a network of regions spanning the brain and brainstem that are involved in limbic, paralimbic, autonomic, cognitive, and sensory domains. This is the first study of its kind to assess the effects of music analgesia using complex network analyses in the human brain and brainstem. Functional MRI data were collected from 20 healthy men and women with concurrent presentation of noxious stimulation and music, in addition to control runs without music. Ratings of peak pain intensity and unpleasantness were collected for each run and were analysed in relation to the functional data. We found that music alters connectivity across these neural networks between regions such as the insula, thalamus, hypothalamus, amygdala and hippocampus (among others), and is impacted by individual pain sensitivity. While these differences are important for how we understand pain and analgesia, it is essential to note that these effects are variable across participants and provide moderate pain relief at best. Therefore, a therapeutic strategy involving music should use it as an adjunct to pain management in combination with healthy lifestyle changes and/or pharmaceutical intervention.
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Affiliation(s)
- Jocelyn M. Powers
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada
| | - Gabriela Ioachim
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada
| | - Patrick W. Stroman
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada
- Department of Physics, Queen's University, Kingston, ON, Canada
- *Correspondence: Patrick W. Stroman
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Ioachim G, Warren HJM, Powers JM, Staud R, Pukall CF, Stroman PW. Altered Pain in the Brainstem and Spinal Cord of Fibromyalgia Patients During the Anticipation and Experience of Experimental Pain. Front Neurol 2022; 13:862976. [PMID: 35599729 PMCID: PMC9120571 DOI: 10.3389/fneur.2022.862976] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 04/07/2022] [Indexed: 11/23/2022] Open
Abstract
Chronic pain associated with fibromyalgia (FM) affects a large portion of the population but the underlying mechanisms leading to this altered pain are still poorly understood. Evidence suggests that FM involves altered neural processes in the central nervous system and neuroimaging methods such as functional magnetic resonance imaging (fMRI) are used to reveal these underlying alterations. While many fMRI studies of FM have been conducted in the brain, recent evidence shows that the changes in pain processing in FM may be linked to autonomic and homeostatic dysregulation, thus requiring further investigation in the brainstem and spinal cord. Functional magnetic resonance imaging data from 15 women with FM and 15 healthy controls were obtained in the cervical spinal cord and brainstem at 3 tesla using previously established methods. In order to investigate differences in pain processing in these groups, participants underwent trials in which they anticipated and received a predictable painful stimulus, randomly interleaved with trials with no stimulus. Differences in functional connectivity between the groups were investigated by means of structural equation modeling. The results demonstrate significant differences in brainstem/spinal cord network connectivity between the FM and control groups which also correlated with individual differences in pain responses. The regions involved in these differences in connectivity included the LC, hypothalamus, PAG, and PBN, which are known to be associated with autonomic homeostatic regulation, including fight or flight responses. This study extends our understanding of altered neural processes associated with FM and the important link between sensory and autonomic regulation systems in this disorder.
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Affiliation(s)
- Gabriela Ioachim
- Center for Neuroscience Studies, Queen's University, Kingston, ON, Canada
| | | | - Jocelyn M. Powers
- Center for Neuroscience Studies, Queen's University, Kingston, ON, Canada
| | - Roland Staud
- Department of Medicine, University of Florida, Seffner, FL, United States
| | - Caroline F. Pukall
- Center for Neuroscience Studies, Queen's University, Kingston, ON, Canada
- Department of Psychology, Queen's University, Kingston, ON, Canada
| | - Patrick W. Stroman
- Center for Neuroscience Studies, Queen's University, Kingston, ON, Canada
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada
- Department of Physics, Queen's University, Kingston, ON, Canada
- *Correspondence: Patrick W. Stroman
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Landelle C, Lungu O, Vahdat S, Kavounoudias A, Marchand-Pauvert V, De Leener B, Doyon J. Investigating the human spinal sensorimotor pathways through functional magnetic resonance imaging. Neuroimage 2021; 245:118684. [PMID: 34732324 DOI: 10.1016/j.neuroimage.2021.118684] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 10/25/2021] [Accepted: 10/25/2021] [Indexed: 01/29/2023] Open
Abstract
Most of our knowledge about the human spinal ascending (sensory) and descending (motor) pathways comes from non-invasive electrophysiological investigations. However, recent methodological advances in acquisition and analyses of functional magnetic resonance imaging (fMRI) data from the spinal cord, either alone or in combination with the brain, have allowed us to gain further insights into the organization of this structure. In the current review, we conducted a systematic search to produced somatotopic maps of the spinal fMRI activity observed through different somatosensory, motor and resting-state paradigms. By cross-referencing these human neuroimaging findings with knowledge acquired through neurophysiological recordings, our review demonstrates that spinal fMRI is a powerful tool for exploring, in vivo, the human spinal cord pathways. We report strong cross-validation between task-related and resting-state fMRI in accordance with well-known hemicord, postero-anterior and rostro-caudal organization of these pathways. We also highlight the specific advantages of using spinal fMRI in clinical settings to characterize better spinal-related impairments, predict disease progression, and guide the implementation of therapeutic interventions.
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Affiliation(s)
- Caroline Landelle
- McConnell Brain Imaging Centre, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada.
| | - Ovidiu Lungu
- McConnell Brain Imaging Centre, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | | | - Anne Kavounoudias
- CNRS, UMR7291, Laboratory of Cognitive Neurosciences, Aix-Marseille University, Marseille, France
| | | | - Benjamin De Leener
- Department of Computer Engineering and Software Engineering, Polytechnique Montreal, Montreal, QC, Canada; CHU Sainte-Justine Research Centre, Montreal, QC, Canada
| | - Julien Doyon
- McConnell Brain Imaging Centre, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
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Zhang L, Wang L, Xia H, Tan Y, Li C, Fang C. Connectomic mapping of brain-spinal cord neural networks: future directions in assessing spinal cord injury at rest. Neurosci Res 2021; 176:9-17. [PMID: 34699861 DOI: 10.1016/j.neures.2021.10.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 10/20/2021] [Accepted: 10/20/2021] [Indexed: 12/01/2022]
Abstract
Following spinal cord injury (SCI), the central nervous system undergoes significant reconstruction. The dynamic change in the interaction of the brain-spinal cord axis as well as in structure-function relations plays a vital role in the determination of neurological functions, which might have important clinical implications for the treatment and its efficacy evaluation of patients with SCI. Brain connectomes based on neuroimaging data is a relatively new field of research that maps the brain's large-scale structural and functional networks at rest. Importantly, increasing evidence shows that such resting-state signals can also be seen in the spinal cord. In the present review, we focus on the reconstruction of multi-level neural circuits after SCI. We also describe how the connectome concept could further our understanding of neuroplasticity after SCI. We propose that mapping the cortical-subcortical-spinal cord networks can provide novel insights into the pathologies of SCI.
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Affiliation(s)
- Lijian Zhang
- Postdoctoral Research Station of Neurosurgery, Affiliated Hospital of Hebei University, Hebei University, China; Department of Neurosurgery, Affiliated Hospital of Hebei University, Hebei University, China; Key Laboratory of Precise Diagnosis and Treatment of Glioma in Hebei Province, Affiliated Hospital of Hebei University, Hebei University, China
| | - Luxuan Wang
- Department of Neurology, Affiliated Hospital of Hebei University, Hebei University, China
| | - Hechun Xia
- Department of Neurosurgery, General Hospital of Ningxia Medical University, Ningxia Medical University, China
| | - Yanli Tan
- Key Laboratory of Precise Diagnosis and Treatment of Glioma in Hebei Province, Affiliated Hospital of Hebei University, Hebei University, China; Department of Pathology, Affiliated Hospital of Hebei University, Hebei University, China.
| | - Chunhui Li
- Department of Neurosurgery, Affiliated Hospital of Hebei University, Hebei University, China.
| | - Chuan Fang
- Postdoctoral Research Station of Neurosurgery, Affiliated Hospital of Hebei University, Hebei University, China; Department of Neurosurgery, Affiliated Hospital of Hebei University, Hebei University, China; Key Laboratory of Precise Diagnosis and Treatment of Glioma in Hebei Province, Affiliated Hospital of Hebei University, Hebei University, China.
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10
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Structural and resting state functional connectivity beyond the cortex. Neuroimage 2021; 240:118379. [PMID: 34252527 DOI: 10.1016/j.neuroimage.2021.118379] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 05/21/2021] [Accepted: 07/07/2021] [Indexed: 12/14/2022] Open
Abstract
Mapping the structural and functional connectivity of the central nervous system has become a key area within neuroimaging research. While detailed network structures across the entire brain have been probed using animal models, non-invasive neuroimaging in humans has thus far been dominated by cortical investigations. Beyond the cortex, subcortical nuclei have traditionally been less accessible due to their smaller size and greater distance from radio frequency coils. However, major neuroimaging developments now provide improved signal and the resolution required to study these structures. Here, we present an overview of the connectivity between the amygdala, brainstem, cerebellum, spinal cord and the rest of the brain. While limitations to their imaging and analyses remain, we also provide some recommendations and considerations for mapping brain connectivity beyond the cortex.
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11
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Stroman PW, Warren HJM, Ioachim G, Powers JM, McNeil K. A comparison of the effectiveness of functional MRI analysis methods for pain research: The new normal. PLoS One 2020; 15:e0243723. [PMID: 33315886 PMCID: PMC7735591 DOI: 10.1371/journal.pone.0243723] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 11/25/2020] [Indexed: 11/18/2022] Open
Abstract
Studies of the neural basis of human pain processing present many challenges because of the subjective and variable nature of pain, and the inaccessibility of the central nervous system. Neuroimaging methods, such as functional magnetic resonance imaging (fMRI), have provided the ability to investigate these neural processes, and yet commonly used analysis methods may not be optimally adapted for studies of pain. Here we present a comparison of model-driven and data-driven analysis methods, specifically for the study of human pain processing. Methods are tested using data from healthy control participants in two previous studies, with separate data sets spanning the brain, and the brainstem and spinal cord. Data are analyzed by fitting time-series responses to predicted BOLD responses in order to identify significantly responding regions (model-driven), as well as with connectivity analyses (data-driven) based on temporal correlations between responses in spatially separated regions, and with connectivity analyses based on structural equation modeling, allowing for multiple source regions to explain the signal variations in each target region. The results are assessed in terms of the amount of signal variance that can be explained in each region, and in terms of the regions and connections that are identified as having BOLD responses of interest. The characteristics of BOLD responses in identified regions are also investigated. The results demonstrate that data-driven approaches are more effective than model-driven approaches for fMRI studies of pain.
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Affiliation(s)
- Patrick W. Stroman
- Centre for Neuroscience Studies, Queen’s University, Kingston, Ontario, Canada
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, Ontario, Canada
- Department of Physics, Queen’s University, Kingston, Ontario, Canada
- * E-mail:
| | - Howard J. M. Warren
- Centre for Neuroscience Studies, Queen’s University, Kingston, Ontario, Canada
| | - Gabriela Ioachim
- Centre for Neuroscience Studies, Queen’s University, Kingston, Ontario, Canada
| | - Jocelyn M. Powers
- Centre for Neuroscience Studies, Queen’s University, Kingston, Ontario, Canada
| | - Kaitlin McNeil
- Centre for Neuroscience Studies, Queen’s University, Kingston, Ontario, Canada
- Royal Military College of Canada, Kingston, Ontario, Canada
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Ioachim G, Powers JM, Warren HJM, Stroman PW. Coordinated Human Brainstem and Spinal Cord Networks during the Expectation of Pain Have Elements Unique from Resting-State Effects. Brain Sci 2020; 10:brainsci10090568. [PMID: 32824896 PMCID: PMC7565010 DOI: 10.3390/brainsci10090568] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/11/2020] [Accepted: 08/17/2020] [Indexed: 12/22/2022] Open
Abstract
Functional magnetic resonance imaging (fMRI) research on the human brainstem (BS) and spinal cord (SC) has identified extensive BS/SC resting-state networks (RSNs) by showing spontaneous coordinated blood oxygenation-level dependent (BOLD) signal fluctuations in the absence of a stimulus. Studies have shown that these networks can be influenced by participants’ level of arousal or attention (e.g., watching a video), and linked network function to autonomic homeostatic regulation. Here we explore how the cognitive state of expecting pain can influence connectivity in these networks. Data from two studies (a predictable pain stimulus study, and a resting-state study) were compared to show the effects of expecting pain on BS/SC networks, and how networks differed from networks associated with the resting-state. In each study, BOLD fMRI data were obtained from the cervical SC and brainstem in healthy participants at 3 tesla using a T2-weighted single-shot fast spin-echo imaging method. Functional connectivity was investigated within the entire 3D volume by means of structural equation modeling (SEM) and analyses of covariance (ANCOVA). Results showed extensive connectivity within/across BS and SC regions during the expectation of pain, and ANCOVA analyses showed that connectivity in specific components of these networks varied with individual pain sensitivity. Comparing these results to RSN fluctuations revealed commonalities in coordination between BS and SC regions, and specific BS–BS connectivity fluctuations unique to the expectation of pain. Based on the regions involved, these results provide evidence of brainstem regulation specific to the expectation of pain.
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Affiliation(s)
- Gabriela Ioachim
- Centre for Neuroscience Studies, Queen’s University, Kingston, ON K7L 3N6, Canada; (G.I.); (J.M.P.); (H.J.M.W.)
| | - Jocelyn M. Powers
- Centre for Neuroscience Studies, Queen’s University, Kingston, ON K7L 3N6, Canada; (G.I.); (J.M.P.); (H.J.M.W.)
| | - Howard J. M. Warren
- Centre for Neuroscience Studies, Queen’s University, Kingston, ON K7L 3N6, Canada; (G.I.); (J.M.P.); (H.J.M.W.)
| | - Patrick W. Stroman
- Centre for Neuroscience Studies, Queen’s University, Kingston, ON K7L 3N6, Canada; (G.I.); (J.M.P.); (H.J.M.W.)
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, ON K7L 3N6, Canada
- Department of Physics, Queen’s University, Kingston, ON K7L 3N6, Canada
- Correspondence: ; Tel.: +1-613-533-3245
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Vahdat S, Khatibi A, Lungu O, Finsterbusch J, Büchel C, Cohen-Adad J, Marchand-Pauvert V, Doyon J. Resting-state brain and spinal cord networks in humans are functionally integrated. PLoS Biol 2020; 18:e3000789. [PMID: 32614823 PMCID: PMC7363111 DOI: 10.1371/journal.pbio.3000789] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 07/15/2020] [Accepted: 06/15/2020] [Indexed: 01/04/2023] Open
Abstract
In the absence of any task, both the brain and spinal cord exhibit spontaneous intrinsic activity organised in a set of functionally relevant neural networks. However, whether such resting-state networks (RSNs) are interconnected across the brain and spinal cord is unclear. Here, we used a unique scanning protocol to acquire functional images of both brain and cervical spinal cord (CSC) simultaneously and examined their spatiotemporal correspondence in humans. We show that the brain and spinal cord activities are strongly correlated during rest periods, and specific spinal cord regions are functionally linked to consistently reported brain sensorimotor RSNs. The functional organisation of these networks follows well-established anatomical principles, including the contralateral correspondence between the spinal hemicords and brain hemispheres as well as sensory versus motor segregation of neural pathways along the brain–spinal cord axis. Thus, our findings reveal a unified functional organisation of sensorimotor networks in the entire central nervous system (CNS) at rest. This neuroimaging study reveals novel insights into the functional organization of resting-state networks in the brain and spinal cord, such as the contralateral correspondence between the two halves of the brain and spinal cord, and segregation of sensory versus motor neural pathways along this axis.
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Affiliation(s)
- Shahabeddin Vahdat
- Centre de recherche de l'Institut Universitaire de Gériatrie de Montréal, Montréal, Quebec, Canada.,Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, United States of America
| | - Ali Khatibi
- McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada.,Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), University of Birmingham, Birmingham, United Kingdom
| | - Ovidiu Lungu
- Centre de recherche de l'Institut Universitaire de Gériatrie de Montréal, Montréal, Quebec, Canada.,McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada.,Department of Psychiatry, University of Montreal, Montreal, Quebec, Canada
| | - Jürgen Finsterbusch
- Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christian Büchel
- Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Julien Cohen-Adad
- Centre de recherche de l'Institut Universitaire de Gériatrie de Montréal, Montréal, Quebec, Canada.,NeuroPoly Lab, Department of Electrical Engineering, Polytechnique Montreal, Montreal, Quebec, Canada
| | | | - Julien Doyon
- Centre de recherche de l'Institut Universitaire de Gériatrie de Montréal, Montréal, Quebec, Canada.,McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
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