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Deng S, Hu Y, Chen S, Xue Y, Yao D, Sun Q, Nedergaard M, Wang W, Ding F. Chronic sleep fragmentation impairs brain interstitial clearance in young wildtype mice. J Cereb Blood Flow Metab 2024:271678X241230188. [PMID: 38639025 DOI: 10.1177/0271678x241230188] [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: 04/20/2024]
Abstract
Accumulating evidence shows that most chronic neurological diseases have a link with sleep disturbances, and that patients with chronically poor sleep undergo an accelerated cognitive decline. Indeed, a single-night of sleep deprivation may increase metabolic waste levels in cerebrospinal fluid. However, it remains unknown how chronic sleep disturbances in isolation from an underlying neurological disease may affect the glymphatic system. Clearance of brain interstitial waste by the glymphatic system occurs primarily during sleep, driven by multiple oscillators including arterial pulsatility, and vasomotion. Herein, we induced sleep fragmentation in young wildtype mice and assessed the effects on glymphatic activity and cognitive functions. Chronic sleep fragmentation reduced glymphatic function and impaired cognitive functions in healthy mice. A mechanistic analysis showed that the chronic sleep fragmentation suppressed slow vasomotion, without altering cardiac-driven pulsations. Taken together, results of this study document that chronic sleep fragmentation suppresses brain metabolite clearance and impairs cognition, even in the absence of disease.
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Affiliation(s)
- Saiyue Deng
- Department of Pharmacology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, 200032, China
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yusi Hu
- Department of Pharmacology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Simiao Chen
- Department of Rehabilitation Medicine, First Affiliated Hospital, Zhejiang University, Hangzhou, 310003, China
| | - Yang Xue
- Department of Neurology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Di Yao
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Qian Sun
- Department of Pharmacology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Maiken Nedergaard
- Division of Glial Disease and Therapeutics, Center for Translational Neuromedicine, Department of Neurology, University of Rochester Medical Center, Rochester, NY, 14642, United States
- Division of Glial Disease and Therapeutics, Center for Translational Neuromedicine, University of Copenhagen, Copenhagen 2200, Denmark
| | - Wei Wang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Fengfei Ding
- Department of Pharmacology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, 200032, China
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
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Burman R, Alperin N. CSF-to-blood toxins clearance is modulated by breathing through cranio-spinal CSF oscillation. J Sleep Res 2024; 33:e14029. [PMID: 37734843 DOI: 10.1111/jsr.14029] [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: 05/18/2023] [Revised: 07/14/2023] [Accepted: 08/16/2023] [Indexed: 09/23/2023]
Abstract
Clearance of brain toxins occurs during sleep, although the mechanism remains unknown. Previous studies implied that the intracranial aqueductal cerebrospinal fluid (CSF) oscillations are involved, but no mechanism was suggested. The rationale for focusing on the aqueductal CSF oscillations is unclear. This study focuses on the cranio-spinal CSF oscillation and the factors that modulate this flow. We propose a mechanism where increased cranio-spinal CSF movements enhance CSF-to-blood metabolic waste clearance through the spinal CSF re-absorption sites. A recent study demonstrating that disturbed sleep impairs CSF-to-blood but not brain-to-CSF clearance, supports the fundamentals of our proposed mechanism. Eight healthy subjects underwent phase-contrast magnetic resonance imaging to quantify the effect of respiration on the cranio-spinal CSF oscillations. Maximal CSF volume displaced from the cranium to the spinal canal during each respiration and cardiac cycle were derived as measures of cranio-spinal CSF mixing level. Transition from normal to slow and abdominal breathing resulted in a 56% increase in the maximal displaced CSF volume. Maximal change in the arterial-venous blood volume, which is the driving force of the CSF oscillations, was increased by 41% during slow abdominal breathing. Cranio-spinal CSF oscillations are driven by the momentary difference between arterial inflow and venous outflow. Breathing modulates the CSF oscillation through changes in the venous outflow. The amount of toxins being transferred to the spinal canal during each respiratory cycle is significantly increased during slow and deeper abdominal breathing, which explains enhanced CSF-to-blood toxins clearance during slow-wave sleep and poor clearance during disrupted sleep.
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Affiliation(s)
- Ritambhar Burman
- Department of Biomedical Engineering, University of Miami, Miami, Florida, USA
| | - Noam Alperin
- Department of Biomedical Engineering, University of Miami, Miami, Florida, USA
- Department of Radiology, Miller School of Medicine, University of Miami, Miami, Florida, USA
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Helakari H, Järvelä M, Väyrynen T, Tuunanen J, Piispala J, Kallio M, Ebrahimi SM, Poltojainen V, Kananen J, Elabasy A, Huotari N, Raitamaa L, Tuovinen T, Korhonen V, Nedergaard M, Kiviniemi V. Effect of sleep deprivation and NREM sleep stage on physiological brain pulsations. Front Neurosci 2023; 17:1275184. [PMID: 38105924 PMCID: PMC10722275 DOI: 10.3389/fnins.2023.1275184] [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: 08/09/2023] [Accepted: 11/02/2023] [Indexed: 12/19/2023] Open
Abstract
Introduction Sleep increases brain fluid transport and the power of pulsations driving the fluids. We investigated how sleep deprivation or electrophysiologically different stages of non-rapid-eye-movement (NREM) sleep affect the human brain pulsations. Methods Fast functional magnetic resonance imaging (fMRI) was performed in healthy subjects (n = 23) with synchronous electroencephalography (EEG), that was used to verify arousal states (awake, N1 and N2 sleep). Cardiorespiratory rates were verified with physiological monitoring. Spectral power analysis assessed the strength, and spectral entropy assessed the stability of the pulsations. Results In N1 sleep, the power of vasomotor (VLF < 0.1 Hz), but not cardiorespiratory pulsations, intensified after sleep deprived vs. non-sleep deprived subjects. The power of all three pulsations increased as a function of arousal state (N2 > N1 > awake) encompassing brain tissue in both sleep stages, but extra-axial CSF spaces only in N2 sleep. Spectral entropy of full band and respiratory pulsations decreased most in N2 sleep stage, while cardiac spectral entropy increased in ventricles. Discussion In summary, the sleep deprivation and sleep depth, both increase the power and harmonize the spectral content of human brain pulsations.
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Affiliation(s)
- Heta Helakari
- Oulu Functional Neuroimaging (OFNI), Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
- Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Matti Järvelä
- Oulu Functional Neuroimaging (OFNI), Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
- Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Tommi Väyrynen
- Oulu Functional Neuroimaging (OFNI), Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
- Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Johanna Tuunanen
- Oulu Functional Neuroimaging (OFNI), Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
- Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Johanna Piispala
- Clinical Neurophysiology, Oulu University Hospital, Oulu, Finland
| | - Mika Kallio
- Clinical Neurophysiology, Oulu University Hospital, Oulu, Finland
| | - Seyed Mohsen Ebrahimi
- Oulu Functional Neuroimaging (OFNI), Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
- Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Valter Poltojainen
- Oulu Functional Neuroimaging (OFNI), Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
- Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Janne Kananen
- Oulu Functional Neuroimaging (OFNI), Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
- Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
- Clinical Neurophysiology, Oulu University Hospital, Oulu, Finland
| | - Ahmed Elabasy
- Oulu Functional Neuroimaging (OFNI), Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
- Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Niko Huotari
- Oulu Functional Neuroimaging (OFNI), Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
- Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Lauri Raitamaa
- Oulu Functional Neuroimaging (OFNI), Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
- Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Timo Tuovinen
- Oulu Functional Neuroimaging (OFNI), Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
- Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Vesa Korhonen
- Oulu Functional Neuroimaging (OFNI), Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
- Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Maiken Nedergaard
- Center of Translational Neuromedicine, University of Copenhagen, Copenhagen, Denmark
- Center of Translational Neuromedicine, University of Rochester, Rochester, NY, United States
| | - Vesa Kiviniemi
- Oulu Functional Neuroimaging (OFNI), Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
- Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
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Liu X. Decoupling Between Brain Activity and Cerebrospinal Fluid Movement in Neurological Disorders. J Magn Reson Imaging 2023:10.1002/jmri.29148. [PMID: 37991132 PMCID: PMC11109023 DOI: 10.1002/jmri.29148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 11/08/2023] [Accepted: 11/09/2023] [Indexed: 11/23/2023] Open
Abstract
Recent research has identified a link between the global mean signal of resting-state functional MRI (fMRI) and macro-scale cerebrospinal fluid movement, indicating the potential link between this resting-state dynamic and brain waste clearance. Consistent with this notion, the strength of this coupling has been associated with multiple neurodegenerative disease pathologies, especially the build-up of toxic proteins. This article aimed to review the latest advancements in this research area, emphasizing studies on spontaneous global brain activity that is tightly linked to the global mean resting-state fMRI signal, and aimed to discuss potential mechanisms through which this activity and associated physiological modulations might affect brain waste clearance. The available evidence supports the presence of a highly organized global brain activity that is linked to arousal and memory systems. This global brain dynamic, along with its associated physiological modulations, has the potential to influence brain waste clearance through multiple pathways through multiple pathways. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 3.
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Affiliation(s)
- Xiao Liu
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
- Institute for Computational and Data Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
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Esfahani MJ, Farboud S, Ngo HVV, Schneider J, Weber FD, Talamini LM, Dresler M. Closed-loop auditory stimulation of sleep slow oscillations: Basic principles and best practices. Neurosci Biobehav Rev 2023; 153:105379. [PMID: 37660843 DOI: 10.1016/j.neubiorev.2023.105379] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 08/25/2023] [Accepted: 08/30/2023] [Indexed: 09/05/2023]
Abstract
Sleep is essential for our physical and mental well-being. During sleep, despite the paucity of overt behavior, our brain remains active and exhibits a wide range of coupled brain oscillations. In particular slow oscillations are characteristic for sleep, however whether they are directly involved in the functions of sleep, or are mere epiphenomena, is not yet fully understood. To disentangle the causality of these relationships, experiments utilizing techniques to detect and manipulate sleep oscillations in real-time are essential. In this review, we first overview the theoretical principles of closed-loop auditory stimulation (CLAS) as a method to study the role of slow oscillations in the functions of sleep. We then describe technical guidelines and best practices to perform CLAS and analyze results from such experiments. We further provide an overview of how CLAS has been used to investigate the causal role of slow oscillations in various sleep functions. We close by discussing important caveats, open questions, and potential topics for future research.
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Affiliation(s)
| | - Soha Farboud
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, the Netherlands
| | - Hong-Viet V Ngo
- Department of Psychology, University of Essex, United Kingdom; Department of Psychology, University of Lübeck, Germany; Center for Brain, Behaviour and Metabolism, University of Lübeck, Germany
| | - Jules Schneider
- Department of Psychiatry and Psychotherapy, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany; Department of Neurology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany
| | - Frederik D Weber
- Donders Institute for Brain, Cognition and Behaviour, Radboudumc, the Netherlands; Department of Sleep and Cognition, Netherlands Institute for Neuroscience, an institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
| | - Lucia M Talamini
- Department of Psychology, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Brain and Cognition, University of Amsterdam, Amsterdam, the Netherlands
| | - Martin Dresler
- Donders Institute for Brain, Cognition and Behaviour, Radboudumc, the Netherlands.
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Vijayakrishnan Nair V, Kish BR, Chong PL, Yang HCS, Wu YC, Tong Y, Schwichtenberg AJ. Neurofluid coupling during sleep and wake states. Sleep Med 2023; 110:44-53. [PMID: 37536211 PMCID: PMC11022242 DOI: 10.1016/j.sleep.2023.07.021] [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: 02/06/2023] [Revised: 07/17/2023] [Accepted: 07/22/2023] [Indexed: 08/05/2023]
Abstract
BACKGROUND In clinical populations, the movement of cerebrospinal fluid (CSF) during sleep is a growing area of research with potential mechanistic connections in both neurodegenerative (e.g., Alzheimer's Disease) and neurodevelopmental disorders. However, we know relatively little about the processes that influence CSF movement. To inform clinical intervention targets this study assesses the coupling between (a) real-time CSF movement, (b) neuronal-driven movement, and (c) non-neuronal systemic physiology driven movement. METHODS This study included eight young, healthy volunteers, with concurrently acquired neurofluid dynamics using functional Magnetic Resonance Imaging (MRI), neural activity using Electroencephalography (EEG), and non-neuronal systemic physiology with peripheral functional Near-Infrared Spectroscopy (fNIRS). Neuronal and non-neuronal drivers were assessed temporally; wherein, EEG measured slow wave activity that preceded CSF movement was considered neuronally driven. Similarly, slow wave oscillations (assessed via fNIRS) that coupled with CSF movement were considered non-neuronal systemic physiology driven. RESULTS AND CONCLUSIONS Our results document neural contributions to CSF movement were only present during light NREM sleep but low-frequency non-neuronal oscillations were strongly coupled with CSF movement in all assessed states - awake, NREM-1, NREM-2. The clinical/research implications of these findings are two-fold. First, neuronal-driven oscillations contribute to CSF movement outside of deep sleep (NREM-3); therefore, interventions aimed at increasing CSF movement may yield meaningful increases with the promotion of NREM sleep more generally - a focus on NREM S3 may not be needed. Second, non-neuronal systemic oscillations contribute across wake and sleep stages; therefore, interventions may increase CSF movement by manipulating systemic physiology.
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Affiliation(s)
| | - Brianna R Kish
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, 47907, USA
| | - Pearlynne Lh Chong
- Department of Human Development and Family Science, College of Health and Human Sciences, Purdue University, West Lafayette, IN, 47907, USA
| | - Ho-Ching Shawn Yang
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Yu-Chien Wu
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Yunjie Tong
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, 47907, USA.
| | - A J Schwichtenberg
- Department of Human Development and Family Science, College of Health and Human Sciences, Purdue University, West Lafayette, IN, 47907, USA.
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Shokri-Kojori E, Tomasi D, Demiral SB, Wang GJ, Volkow ND. An autonomic mode of brain activity. Prog Neurobiol 2023; 229:102510. [PMID: 37516341 PMCID: PMC10591458 DOI: 10.1016/j.pneurobio.2023.102510] [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: 02/07/2023] [Revised: 05/11/2023] [Accepted: 07/18/2023] [Indexed: 07/31/2023]
Abstract
The relevance of interactions between autonomic and central nervous systems remains unclear for human brain function and health, particularly when both systems are challenged under sleep deprivation (SD). We measured brain activity (with fMRI), pulse and respiratory signals, and baseline brain amyloid beta burden (with PET) in healthy participants. We found that SD relative to rested wakefulness (RW) resulted in a significant increase in synchronized low frequency (LF, < 0.1 Hz) activity in an autonomically-related network (AN), including dorsal attention, visual, and sensorimotor regions, which we previously found to have consistent temporal coupling with LF pulse signal changes (regulated by sympathetic tone). SD resulted in a significant phase coherence between the LF component of the pulse signal and a medial network with peak effects in the midbrain reticular formation, and between LF component of the respiratory variations (regulated by respiratory motor output) and a cerebellar network. The LF power of AN during SD was significantly and independently correlated with pulse-medial network and respiratory-cerebellar network phase coherences (total adjusted R2 = 0.78). Higher LF power of AN during SD (but not RW) was associated with lower amyloid beta burden (Cohen's d = 0.8). In sum, SD triggered an autonomic mode of synchronized brain activity that was associated with distinct autonomic-central interactions. Findings highlight the direct relevance of global cortical synchronization to brain clearance mechanisms.
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Affiliation(s)
- Ehsan Shokri-Kojori
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA.
| | - Dardo Tomasi
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Sukru B Demiral
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Gene-Jack Wang
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Nora D Volkow
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
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8
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Han F, Lee J, Chen X, Ziontz J, Ward T, Landau SM, Baker SL, Harrison TM, Jagust WJ. Global brain activity and its coupling with cerebrospinal fluid flow is related to tau pathology. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.12.557492. [PMID: 37745434 PMCID: PMC10515801 DOI: 10.1101/2023.09.12.557492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Amyloid-β (Aβ) and tau deposition constitute Alzheimer's disease (AD) neuropathology. Cortical tau deposits first in the entorhinal cortex and hippocampus and then propagates to neocortex in an Aβ-dependent manner. Tau also tends to accumulate earlier in higher-order association cortex than in lower-order primary sensory-motor cortex. While previous research has examined the production and spread of tau, little attention has been paid to its clearance. Low-frequency (<0.1 Hz) global brain activity during the resting state is coupled with cerebrospinal fluid (CSF) flow and potentially reflects glymphatic clearance. Here we report that tau deposition in subjects with evaluated Aβ, accompanied by cortical thinning and cognitive decline, is strongly associated with decreased coupling between CSF flow and global brain activity. Substantial modulation of global brain activity is also manifested as propagating waves of brain activation between higher- and lower-order regions, resembling tau spreading. Together, the findings suggest an important role of resting-state global brain activity in AD tau pathology.
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Affiliation(s)
- Feng Han
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - JiaQie Lee
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - Xi Chen
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Jacob Ziontz
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - Tyler Ward
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - Susan M Landau
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | | | - Theresa M Harrison
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - William J Jagust
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA
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Ungurean G, Behroozi M, Böger L, Helluy X, Libourel PA, Güntürkün O, Rattenborg NC. Wide-spread brain activation and reduced CSF flow during avian REM sleep. Nat Commun 2023; 14:3259. [PMID: 37277328 DOI: 10.1038/s41467-023-38669-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 05/03/2023] [Indexed: 06/07/2023] Open
Abstract
Mammalian sleep has been implicated in maintaining a healthy extracellular environment in the brain. During wakefulness, neuronal activity leads to the accumulation of toxic proteins, which the glymphatic system is thought to clear by flushing cerebral spinal fluid (CSF) through the brain. In mice, this process occurs during non-rapid eye movement (NREM) sleep. In humans, ventricular CSF flow has also been shown to increase during NREM sleep, as visualized using functional magnetic resonance imaging (fMRI). The link between sleep and CSF flow has not been studied in birds before. Using fMRI of naturally sleeping pigeons, we show that REM sleep, a paradoxical state with wake-like brain activity, is accompanied by the activation of brain regions involved in processing visual information, including optic flow during flight. We further demonstrate that ventricular CSF flow increases during NREM sleep, relative to wakefulness, but drops sharply during REM sleep. Consequently, functions linked to brain activation during REM sleep might come at the expense of waste clearance during NREM sleep.
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Affiliation(s)
- Gianina Ungurean
- Avian Sleep Group, Max Planck Institute for Biological Intelligence, Seewiesen, Germany.
| | - Mehdi Behroozi
- Department of Biopsychology, Institute of Cognitive Neuroscience, Faculty of Psychology, Ruhr-University Bochum, Bochum, Germany.
| | - Leonard Böger
- Max-Planck Research Group Neural Information Flow, Max Planck Institute for the Neurobiology of Behavior - caesar, Bonn, Germany
- Max-Planck Research Group Genetics of Behaviour, Max Planck Institute for the Neurobiology of Behavior - caesar, Bonn, Germany
| | - Xavier Helluy
- Department of Biopsychology, Institute of Cognitive Neuroscience, Faculty of Psychology, Ruhr-University Bochum, Bochum, Germany
- Department of Neurophysiology, Medical Faculty, Ruhr-University Bochum, Bochum, Germany
| | - Paul-Antoine Libourel
- CRNL, SLEEP Team, UMR 5292 CNRS/U1028 INSERM, Université Claude Bernard Lyon 1, Lyon, Bron, France
| | - Onur Güntürkün
- Department of Biopsychology, Institute of Cognitive Neuroscience, Faculty of Psychology, Ruhr-University Bochum, Bochum, Germany
- Research Center One Health Ruhr, Research Alliance Ruhr, Ruhr-University Bochum, Bochum, Germany
| | - Niels C Rattenborg
- Avian Sleep Group, Max Planck Institute for Biological Intelligence, Seewiesen, Germany
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10
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Kong SDX, Gordon CJ, Hoyos CM, Wassing R, D’Rozario A, Mowszowski L, Ireland C, Palmer JR, Grunstein RR, Shine JM, McKinnon AC, Naismith SL. Heart rate variability during slow wave sleep is linked to functional connectivity in the central autonomic network. Brain Commun 2023; 5:fcad129. [PMID: 37234683 PMCID: PMC10208252 DOI: 10.1093/braincomms/fcad129] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 02/20/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023] Open
Abstract
Reduced heart rate variability can be an early sign of autonomic dysfunction in neurodegenerative diseases and may be related to brain dysfunction in the central autonomic network. As yet, such autonomic dysfunction has not been examined during sleep-which is an ideal physiological state to study brain-heart interaction as both the central and peripheral nervous systems behave differently compared to during wakefulness. Therefore, the primary aim of the current study was to examine whether heart rate variability during nocturnal sleep, specifically slow wave (deep) sleep, is associated with central autonomic network functional connectivity in older adults 'at-risk' of dementia. Older adults (n = 78; age range = 50-88 years; 64% female) attending a memory clinic for cognitive concerns underwent resting-state functional magnetic resonance imaging and an overnight polysomnography. From these, central autonomic network functional connectivity strength and heart rate variability data during sleep were derived, respectively. High-frequency heart rate variability was extracted to index parasympathetic activity during distinct periods of sleep, including slow wave sleep as well as secondary outcomes of non-rapid eye movement sleep, wake after sleep onset, and rapid eye movement sleep. General linear models were used to examine associations between central autonomic network functional connectivity and high-frequency heart rate variability. Analyses revealed that increased high-frequency heart rate variability during slow wave sleep was associated with stronger functional connectivity (F = 3.98, P = 0.022) in two core brain regions within the central autonomic network, the right anterior insular and posterior midcingulate cortex, as well as stronger functional connectivity (F = 6.21, P = 0.005) between broader central autonomic network brain regions-the right amygdala with three sub-nuclei of the thalamus. There were no significant associations between high-frequency heart rate variability and central autonomic network connectivity during wake after sleep onset or rapid eye movement sleep. These findings show that in older adults 'at-risk' of dementia, parasympathetic regulation during slow wave sleep is uniquely linked to differential functional connectivity within both core and broader central autonomic network brain regions. It is possible that dysfunctional brain-heart interactions manifest primarily during this specific period of sleep known for its role in memory and metabolic clearance. Further studies elucidating the pathophysiology and directionality of this relationship should be conducted to determine if heart rate variability drives neurodegeneration, or if brain degeneration within the central autonomic network promotes aberrant heart rate variability.
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Affiliation(s)
- Shawn D X Kong
- Correspondence to: Shawn Dexiao KongHealthy Brain Ageing ProgramBrain and Mind Centre, University of Sydney100 Mallett St, Camperdown, NSW 2050, Australia E-mail:
| | - Christopher J Gordon
- CIRUS, Centre for Sleep and Chronobiology, Woolcock Institute of Medical Research, University of Sydney, Glebe, NSW 2037, Australia
- Faculty of Medicine and Health, University of Sydney, Camperdown, NSW 2050, Australia
| | - Camilla M Hoyos
- Healthy Brain Ageing Program, Brain and Mind Centre, University of Sydney, Camperdown, NSW 2050, Australia
- Charles Perkins Centre, University of Sydney, Camperdown, NSW 2050, Australia
- School of Psychology, Faculty of Science, University of Sydney, Camperdown, NSW 2050, Australia
- CIRUS, Centre for Sleep and Chronobiology, Woolcock Institute of Medical Research, University of Sydney, Glebe, NSW 2037, Australia
| | - Rick Wassing
- CIRUS, Centre for Sleep and Chronobiology, Woolcock Institute of Medical Research, University of Sydney, Glebe, NSW 2037, Australia
| | - Angela D’Rozario
- Healthy Brain Ageing Program, Brain and Mind Centre, University of Sydney, Camperdown, NSW 2050, Australia
- School of Psychology, Faculty of Science, University of Sydney, Camperdown, NSW 2050, Australia
- CIRUS, Centre for Sleep and Chronobiology, Woolcock Institute of Medical Research, University of Sydney, Glebe, NSW 2037, Australia
| | - Loren Mowszowski
- Healthy Brain Ageing Program, Brain and Mind Centre, University of Sydney, Camperdown, NSW 2050, Australia
- Charles Perkins Centre, University of Sydney, Camperdown, NSW 2050, Australia
- School of Psychology, Faculty of Science, University of Sydney, Camperdown, NSW 2050, Australia
| | - Catriona Ireland
- Healthy Brain Ageing Program, Brain and Mind Centre, University of Sydney, Camperdown, NSW 2050, Australia
| | - Jake R Palmer
- Healthy Brain Ageing Program, Brain and Mind Centre, University of Sydney, Camperdown, NSW 2050, Australia
| | - Ronald R Grunstein
- CIRUS, Centre for Sleep and Chronobiology, Woolcock Institute of Medical Research, University of Sydney, Glebe, NSW 2037, Australia
- Faculty of Medicine and Health, University of Sydney, Camperdown, NSW 2050, Australia
- Royal Prince Alfred Hospital, University of Sydney, Camperdown, NSW 2050, Australia
| | - James M Shine
- Royal Prince Alfred Hospital, University of Sydney, Camperdown, NSW 2050, Australia
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11
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Kjaerby C, Andersen M, Hauglund N, Untiet V, Dall C, Ding F, Hirase H, Nedergaard M. Reply to: 'Do all norepinephrine surges disrupt sleep?'. Nat Neurosci 2023:10.1038/s41593-023-01314-7. [PMID: 37081298 DOI: 10.1038/s41593-023-01314-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 03/20/2023] [Indexed: 04/22/2023]
Affiliation(s)
- Celia Kjaerby
- Division of Glial Disease and Therapeutics, Center for Translational Neuromedicine, University of Copenhagen, Copenhagen, Denmark.
| | - Mie Andersen
- Division of Glial Disease and Therapeutics, Center for Translational Neuromedicine, University of Copenhagen, Copenhagen, Denmark
| | - Natalie Hauglund
- Division of Glial Disease and Therapeutics, Center for Translational Neuromedicine, University of Copenhagen, Copenhagen, Denmark
| | - Verena Untiet
- Division of Glial Disease and Therapeutics, Center for Translational Neuromedicine, University of Copenhagen, Copenhagen, Denmark
| | - Camilla Dall
- Division of Glial Disease and Therapeutics, Center for Translational Neuromedicine, University of Copenhagen, Copenhagen, Denmark
| | - Fengfei Ding
- Department of Neurosurgery, University of Rochester Medical Center, Rochester, NY, USA
| | - Hajime Hirase
- Division of Glial Disease and Therapeutics, Center for Translational Neuromedicine, University of Copenhagen, Copenhagen, Denmark
- Department of Neurosurgery, University of Rochester Medical Center, Rochester, NY, USA
| | - Maiken Nedergaard
- Division of Glial Disease and Therapeutics, Center for Translational Neuromedicine, University of Copenhagen, Copenhagen, Denmark.
- Department of Neurosurgery, University of Rochester Medical Center, Rochester, NY, USA.
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12
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Elabasy A, Suhonen M, Rajna Z, Hosni Y, Kananen J, Annunen J, Ansakorpi H, Korhonen V, Seppänen T, Kiviniemi V. Respiratory brain impulse propagation in focal epilepsy. Sci Rep 2023; 13:5222. [PMID: 36997658 PMCID: PMC10063583 DOI: 10.1038/s41598-023-32271-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 03/24/2023] [Indexed: 04/03/2023] Open
Abstract
Respiratory brain pulsations pertaining to intra-axial hydrodynamic solute transport are markedly altered in focal epilepsy. We used optical flow analysis of ultra-fast functional magnetic resonance imaging (fMRI) data to investigate the velocity characteristics of respiratory brain impulse propagation in patients with focal epilepsy treated with antiseizure medication (ASM) (medicated patients with focal epilepsy; ME, n = 23), drug-naïve patients with at least one seizure (DN, n = 19) and matched healthy control subjects (HC, n = 75). We detected in the two patient groups (ME and DN) several significant alterations in the respiratory brain pulsation propagation velocity, which showed a bidirectional change dominated by a reduction in speed. Furthermore, the respiratory impulses moved more in reversed or incoherent directions in both patient groups vs. the HC group. The speed reductions and directionality changes occurred in specific phases of the respiratory cycle. In conclusion, irrespective of medication status, both patient groups showed incoherent and slower respiratory brain impulses, which may contribute to epileptic brain pathology by hindering brain hydrodynamics.
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Affiliation(s)
- Ahmed Elabasy
- Center for Machine Vision and Signal Analysis, University of Oulu, 90014, Oulu, Finland.
- Oulu Functional NeuroImaging, Diagnostic Radiology, Medical Research Center/HTS, Oulu University Hospital, 90029, Oulu, Finland.
| | - Mia Suhonen
- Medical Imaging, Physics and Technology, University of Oulu, 90029, Oulu, Finland.
- Oulu Functional NeuroImaging, Diagnostic Radiology, Medical Research Center/HTS, Oulu University Hospital, 90029, Oulu, Finland.
| | - Zalan Rajna
- Center for Machine Vision and Signal Analysis, University of Oulu, 90014, Oulu, Finland
| | - Youssef Hosni
- Center for Machine Vision and Signal Analysis, University of Oulu, 90014, Oulu, Finland
- Oulu Functional NeuroImaging, Diagnostic Radiology, Medical Research Center/HTS, Oulu University Hospital, 90029, Oulu, Finland
| | - Janne Kananen
- Medical Imaging, Physics and Technology, University of Oulu, 90029, Oulu, Finland
- Oulu Functional NeuroImaging, Diagnostic Radiology, Medical Research Center/HTS, Oulu University Hospital, 90029, Oulu, Finland
- Clinical Neurophysiology, Oulu University Hospital, 90029 OYS, Oulu, Finland
| | - Johanna Annunen
- Research Unit of Clinical Neuroscience, Neurology, University of Oulu, 90029, Oulu, Finland
- Neurocenter, Neurology, Oulu University Hospital, Member of ERN EpiCARE, 90029, Oulu, Finland
- MRC, Oulu University Hospital, 90029, Oulu, Finland
| | - Hanna Ansakorpi
- Research Unit of Clinical Neuroscience, Neurology, University of Oulu, 90029, Oulu, Finland
| | - Vesa Korhonen
- Medical Imaging, Physics and Technology, University of Oulu, 90029, Oulu, Finland
- Oulu Functional NeuroImaging, Diagnostic Radiology, Medical Research Center/HTS, Oulu University Hospital, 90029, Oulu, Finland
| | - Tapio Seppänen
- Center for Machine Vision and Signal Analysis, University of Oulu, 90014, Oulu, Finland
| | - Vesa Kiviniemi
- Medical Imaging, Physics and Technology, University of Oulu, 90029, Oulu, Finland.
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13
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Williams SD, Setzer B, Fultz NE, Valdiviezo Z, Tacugue N, Diamandis Z, Lewis LD. Neural activity induced by sensory stimulation can drive large-scale cerebrospinal fluid flow during wakefulness in humans. PLoS Biol 2023; 21:e3002035. [PMID: 36996009 PMCID: PMC10062585 DOI: 10.1371/journal.pbio.3002035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 02/15/2023] [Indexed: 03/31/2023] Open
Abstract
Cerebrospinal fluid (CSF) flow maintains healthy brain homeostasis, facilitating solute transport and the exchange of brain waste products. CSF flow is thus important for brain health, but the mechanisms that control its large-scale movement through the ventricles are not well understood. While it is well established that CSF flow is modulated by respiratory and cardiovascular dynamics, recent work has also demonstrated that neural activity is coupled to large waves of CSF flow in the ventricles during sleep. To test whether the temporal coupling between neural activity and CSF flow is in part due to a causal relationship, we investigated whether CSF flow could be induced by driving neural activity with intense visual stimulation. We manipulated neural activity with a flickering checkerboard visual stimulus and found that we could drive macroscopic CSF flow in the human brain. The timing and amplitude of CSF flow was matched to the visually evoked hemodynamic responses, suggesting neural activity can modulate CSF flow via neurovascular coupling. These results demonstrate that neural activity can contribute to driving CSF flow in the human brain and that the temporal dynamics of neurovascular coupling can explain this effect.
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Affiliation(s)
- Stephanie D. Williams
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts, United States of America
- Department of Psychological and Brain Sciences, Boston University, Boston, Massachusetts, United States of America
| | - Beverly Setzer
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts, United States of America
- Graduate Program in Neuroscience, Boston University, Boston, Massachusetts, United States of America
| | - Nina E. Fultz
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts, United States of America
| | - Zenia Valdiviezo
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts, United States of America
| | - Nicole Tacugue
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts, United States of America
| | - Zachary Diamandis
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts, United States of America
| | - Laura D. Lewis
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts, United States of America
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14
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Tu W, Zhang N. Neural underpinning of a respiration-associated resting-state fMRI network. eLife 2022; 11:e81555. [PMID: 36263940 PMCID: PMC9645809 DOI: 10.7554/elife.81555] [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: 07/01/2022] [Accepted: 10/13/2022] [Indexed: 11/13/2022] Open
Abstract
Respiration can induce motion and CO2 fluctuation during resting-state fMRI (rsfMRI) scans, which will lead to non-neural artifacts in the rsfMRI signal. In the meantime, as a crucial physiologic process, respiration can directly drive neural activity change in the brain, and may thereby modulate the rsfMRI signal. Nonetheless, this potential neural component in the respiration-fMRI relationship is largely unexplored. To elucidate this issue, here we simultaneously recorded the electrophysiology, rsfMRI, and respiration signals in rats. Our data show that respiration is indeed associated with neural activity changes, evidenced by a phase-locking relationship between slow respiration variations and the gamma-band power of the electrophysiological signal recorded in the anterior cingulate cortex. Intriguingly, slow respiration variations are also linked to a characteristic rsfMRI network, which is mediated by gamma-band neural activity. In addition, this respiration-related brain network disappears when brain-wide neural activity is silenced at an isoelectrical state, while the respiration is maintained, further confirming the necessary role of neural activity in this network. Taken together, this study identifies a respiration-related brain network underpinned by neural activity, which represents a novel component in the respiration-rsfMRI relationship that is distinct from respiration-related rsfMRI artifacts. It opens a new avenue for investigating the interactions between respiration, neural activity, and resting-state brain networks in both healthy and diseased conditions.
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Affiliation(s)
- Wenyu Tu
- The Neuroscience Graduate Program, The Huck Institutes of the Life Sciences, The Pennsylvania State UniversityUniversity ParkUnited States
- Center for Neurotechnology in Mental Health Research, The Pennsylvania State UniversityUniversity ParkUnited States
| | - Nanyin Zhang
- The Neuroscience Graduate Program, The Huck Institutes of the Life Sciences, The Pennsylvania State UniversityUniversity ParkUnited States
- Center for Neurotechnology in Mental Health Research, The Pennsylvania State UniversityUniversity ParkUnited States
- Department of Biomedical Engineering, The Pennsylvania State UniversityUniversity ParkUnited States
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15
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Memory-enhancing properties of sleep depend on the oscillatory amplitude of norepinephrine. Nat Neurosci 2022; 25:1059-1070. [PMID: 35798980 PMCID: PMC9817483 DOI: 10.1038/s41593-022-01102-9] [Citation(s) in RCA: 73] [Impact Index Per Article: 36.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 05/19/2022] [Indexed: 01/11/2023]
Abstract
Sleep has a complex micro-architecture, encompassing micro-arousals, sleep spindles and transitions between sleep stages. Fragmented sleep impairs memory consolidation, whereas spindle-rich and delta-rich non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep promote it. However, the relationship between micro-arousals and memory-promoting aspects of sleep remains unclear. In this study, we used fiber photometry in mice to examine how release of the arousal mediator norepinephrine (NE) shapes sleep micro-architecture. Here we show that micro-arousals are generated in a periodic pattern during NREM sleep, riding on the peak of locus-coeruleus-generated infraslow oscillations of extracellular NE, whereas descending phases of NE oscillations drive spindles. The amplitude of NE oscillations is crucial for shaping sleep micro-architecture related to memory performance: prolonged descent of NE promotes spindle-enriched intermediate state and REM sleep but also associates with awakenings, whereas shorter NE descents uphold NREM sleep and micro-arousals. Thus, the NE oscillatory amplitude may be a target for improving sleep in sleep disorders.
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16
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Newell DW, Nedergaard M, Aaslid R. Physiological Mechanisms and Significance of Intracranial B Waves. Front Neurol 2022; 13:872701. [PMID: 35651339 PMCID: PMC9149212 DOI: 10.3389/fneur.2022.872701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 04/20/2022] [Indexed: 12/03/2022] Open
Abstract
Objective Recently published studies have described slow spontaneous cerebral blood flow (CBF) and cerebrospinal fluid (CSF) oscillations measured by magnetic resonance imaging (MRI) as potential drivers of brain glymphatic flow, with a similar frequency as intracranial B-waves. Aiming to establish the relationship between these waveforms, we performed additional analysis of frequency and waveform parameters, of our previously published transcranial Doppler (TCD) and intracranial pressure (ICP) recordings of intracranial B waves, to compare to published MRI frequency measurements of CBF and CSF slow oscillations. Patients and Methods We analyzed digital recordings of B waves in 29 patients with head injury, including middle cerebral artery (MCA) flow velocity (FV), ICP, end tidal CO2, and arterial blood pressure (ABP). A subset of these recordings demonstrated high B wave activity and was further analyzed for parameters including frequency, interaction, and waveform distribution curve features. These measures were compared to published similar measurements of spontaneous CBF and CSF fluctuations evaluated using MRI. Results In patients with at least 10% amplitude B wave activity, the MCA blood flow velocity oscillations comprising the B waves, had a maximum amplitude at 0.0245 Hz, and time derivative a maximum amplitude at 0.035 Hz. The frequency range of the B waves was between 0.6–2.3 cycles per min (0.011-0.038 Hz), which is in the same range as MRI measured CBF slow oscillations, reported in human volunteers. Waveform asymmetry in MCA velocity and ICP cycles during B waves, was also similar to published MRI measured CBF slow oscillations. Cross-correlation analysis showed equivalent time derivatives of FV vs. ICP in B waves, compared to MRI measured CBF slow oscillations vs. CSF flow fluctuations. Conclusions The TCD and ICP recordings of intracranial B waves show a similar frequency range as CBF and CSF flow oscillations measured using MRI, and share other unique morphological wave features. These findings strongly suggest a common physiological mechanism underlying the two classes of phenomena. The slow blood flow and volume oscillations causing intracranial B waves appear to be part of a cascade that may provide a significant driving force for compartmentalized CSF movement and facilitate glymphatic flow.
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Affiliation(s)
- David W Newell
- Department of Neurosurgery, Seattle Neuroscience Institute, Seattle, WA, United States
| | - Maiken Nedergaard
- Department of Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Translational Neuromedicine, University of Rochester Medical School, Rochester, NY, United States
| | - Rune Aaslid
- Department of Neurosurgery, University of Bern, Bern, Switzerland
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