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Smith LJ, Wilkinson D, Bodani M, Surenthiran SS. Cognition in vestibular disorders: state of the field, challenges, and priorities for the future. Front Neurol 2024; 15:1159174. [PMID: 38304077 PMCID: PMC10830645 DOI: 10.3389/fneur.2024.1159174] [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: 02/05/2023] [Accepted: 01/05/2024] [Indexed: 02/03/2024] Open
Abstract
Vestibular disorders are prevalent and debilitating conditions of the inner ear and brain which affect balance, coordination, and the integration of multisensory inputs. A growing body of research has linked vestibular disorders to cognitive problems, most notably attention, visuospatial perception, spatial memory, and executive function. However, the mechanistic bases of these cognitive sequelae remain poorly defined, and there is a gap between our theoretical understanding of vestibular cognitive dysfunction, and how best to identify and manage this within clinical practice. This article takes stock of these shortcomings and provides recommendations and priorities for healthcare professionals who assess and treat vestibular disorders, and for researchers developing cognitive models and rehabilitation interventions. We highlight the importance of multidisciplinary collaboration for developing and evaluating clinically relevant theoretical models of vestibular cognition, to advance research and treatment.
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Affiliation(s)
- Laura J. Smith
- Centre for Preventative Neurology, Wolfson Institute of Population Health, Queen Mary University of London, London, United Kingdom
- School of Psychology, Keynes College, University of Kent, Kent, United Kingdom
| | - David Wilkinson
- School of Psychology, Keynes College, University of Kent, Kent, United Kingdom
| | - Mayur Bodani
- School of Psychology, Keynes College, University of Kent, Kent, United Kingdom
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Kwon KJ, Byun JY. Asymmetry of Gray- and White-Matter Volume and Metabolites in the Central-Vestibular System in Healthy Individuals. J Clin Med 2023; 12:jcm12041272. [PMID: 36835808 PMCID: PMC9967821 DOI: 10.3390/jcm12041272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/25/2023] [Accepted: 02/04/2023] [Indexed: 02/09/2023] Open
Abstract
This study was designed to determine whether there was an asymmetry of structure and neurochemical activity of the interhemispheric vestibular-cortical system between healthy individuals and patients with vestibular failure. Previous studies have identified differences in gray-matter-volume (GMV) and white-matter-volume (WMV) asymmetry in the central-vestibular system and in concentrations of brain metabolites in the parietal lobe 2 (PO2) between patients with vestibulopathy and healthy controls. However, a comparison of the left and right sides in the healthy controls has not been made conclusively. This study included 23 healthy right-handed volunteers, and was carried out between March 2016 and March 2020. A three-dimensional T1-weighted image was used to calculate the GMV and WMV of the central-vestibular network on both sides, and proton magnetic resonance spectroscopy (H1MRS) was employed to analyze the brain metabolites in the PO2 area. The relative ratios of N-acetylaspartate (NAA)/tCr, tNAA/tCr, glycerophosphocholine (GPC)/tCr, Glx/tCr, and myo-inositol/tCr were quantified from the proton-MRS data. GMV and WMV differed significantly between the right and left vestibular-cortical regions. The GMVs of the right PO2, caudate, insula, and precuneus were significantly higher than those of the same locations on the left side; however, in the Rolandic operculum, the GMV on the left was significantly higher than on the right. In the PO2, Rolandic operculum, thalamus, and insula, the WMV on the left side was higher than on the right side of the corresponding location. However, the right caudate and precuneus WMV were higher than the left at the same location. In the H1MRS study, the Glx/tCr and GPC/tCr ratios on the left side were significantly higher than on the right. In comparison, the NAA/tCr and tNAA/tCr ratios showed contrasting results. The NAA/tCr ratio (r = -0.478, p = 0.021), tNAA/tCr ratio (r = -0.537, p = 0.008), and Glx/tCr ratio (r = -0.514, p = 0.012) on the right side showed a significant negative correlation with the participants' age. There was no relationship between GMV and metabolites on either side. Brain structure and concentrations of brain metabolites related to the vestibular system may differ between the two hemispheres in healthy individuals. Therefore, the asymmetry of the central-vestibular system should be considered when performing imaging.
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Vestibular paroxysmia entails vestibular nerve function, microstructure and endolymphatic space changes linked to root-entry zone neurovascular compression. J Neurol 2023; 270:82-100. [PMID: 36255522 DOI: 10.1007/s00415-022-11399-y] [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: 11/24/2021] [Revised: 09/22/2022] [Accepted: 09/23/2022] [Indexed: 01/07/2023]
Abstract
Combining magnetic resonance imaging (MRI) sequences that permit the determination of vestibular nerve angulation (NA = change of nerve caliber or direction), structural nerve integrity via diffusion tensor imaging (DTI), and exclusion of endolymphatic hydrops (ELH) via delayed gadolinium-enhanced MRI of the inner ear (iMRI) could increase the diagnostic accuracy in patients with vestibular paroxysmia (VP). Thirty-six participants were examined, 18 with VP (52.6 ± 18.1 years) and 18 age-matched with normal vestibulocochlear testing (NP 50.3 ± 16.5 years). This study investigated whether (i) NA, (ii) DTI changes, or (iii) ELH occur in VP, and (iv) to what extent said parameters relate. Methods included vestibulocochlear testing and MRI data analyses for neurovascular compression (NVC) and NA verification, DTI and ELS quantification. As a result, (i) NA increased NVC specificity. (ii) DTI structural integrity was reduced on the side affected by VP (p < 0.05). (iii) 61.1% VP showed mild ELH and higher asymmetry indices than NP (p > 0.05). (iv) "Disease duration" and "total number of attacks" correlated with the decreased structural integrity of the affected nerve in DTI (p < 0.001). NVC distance within the nerve's root-entry zone correlated with nerve function (Roh = 0.72, p < 0.001), nerve integrity loss (Roh = - 0.638, p < 0.001), and ELS volume (Roh = - 0.604, p < 0.001) in VP. In conclusion, this study is the first to link eighth cranial nerve function, microstructure, and ELS changes in VP to clinical features and increased vulnerability of NVC in the root-entry zone. Combined MRI with NVC or NA verification, DTI and ELS quantification increased the diagnostic accuracy at group-level but did not suffice to diagnose VP on a single-subject level due to individual variability and lack of diagnostic specificity.
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Gabriel GA, Harris LR, Gnanasegaram JJ, Cushing SL, Gordon KA, Haycock BC, Campos JL. Age-related changes to vestibular heave and pitch perception and associations with postural control. Sci Rep 2022; 12:6426. [PMID: 35440744 PMCID: PMC9018785 DOI: 10.1038/s41598-022-09807-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 03/21/2022] [Indexed: 11/09/2022] Open
Abstract
Falls are a common cause of injury in older adults (OAs), and age-related declines across the sensory systems are associated with increased falls risk. The vestibular system is particularly important for maintaining balance and supporting safe mobility, and aging has been associated with declines in vestibular end-organ functioning. However, few studies have examined potential age-related differences in vestibular perceptual sensitivities or their association with postural stability. Here we used an adaptive-staircase procedure to measure detection and discrimination thresholds in 19 healthy OAs and 18 healthy younger adults (YAs), by presenting participants with passive heave (linear up-and-down translations) and pitch (forward-backward tilt rotations) movements on a motion-platform in the dark. We also examined participants' postural stability under various standing-balance conditions. Associations among these postural measures and vestibular perceptual thresholds were further examined. Ultimately, OAs showed larger heave and pitch detection thresholds compared to YAs, and larger perceptual thresholds were associated with greater postural sway, but only in OAs. Overall, these results suggest that vestibular perceptual sensitivity declines with older age and that such declines are associated with poorer postural stability. Future studies could consider the potential applicability of these results in the development of screening tools for falls prevention in OAs.
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Affiliation(s)
- Grace A Gabriel
- KITE-Toronto Rehabilitation Institute, University Health Network, Toronto, ON, Canada.,Department of Psychology, University of Toronto, 500 University Avenue, Toronto, ON, M5G 2A2, Canada
| | - Laurence R Harris
- Department of Psychology and Centre for Vision Research, York University, Toronto, ON, Canada
| | - Joshua J Gnanasegaram
- KITE-Toronto Rehabilitation Institute, University Health Network, Toronto, ON, Canada
| | - Sharon L Cushing
- Department of Otolaryngology-Head and Neck Surgery, Hospital for Sick Children, Toronto, ON, Canada.,Department of Otolaryngology-Head and Neck Surgery, University of Toronto, Toronto, ON, Canada.,Archie's Cochlear Implant Laboratory, Hospital for Sick Children, Toronto, ON, Canada
| | - Karen A Gordon
- Department of Otolaryngology-Head and Neck Surgery, University of Toronto, Toronto, ON, Canada.,Archie's Cochlear Implant Laboratory, Hospital for Sick Children, Toronto, ON, Canada
| | - Bruce C Haycock
- KITE-Toronto Rehabilitation Institute, University Health Network, Toronto, ON, Canada.,University of Toronto Institute for Aerospace Studies, Toronto, ON, Canada
| | - Jennifer L Campos
- KITE-Toronto Rehabilitation Institute, University Health Network, Toronto, ON, Canada. .,Department of Psychology, University of Toronto, 500 University Avenue, Toronto, ON, M5G 2A2, Canada.
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Hou J, Mohanty R, Chu D, Nair VA, Danilov Y, Kaczmarek KA, Meyerand B, Tyler M, Prabhakaran V. Translingual neural stimulation affects resting-state functional connectivity in mild-moderate traumatic brain injury. J Neuroimaging 2022; 32:1193-1200. [PMID: 35906713 PMCID: PMC9649856 DOI: 10.1111/jon.13029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND AND PURPOSE Traumatic brain injury (TBI) can lead to movement and balance deficits. In addition to physical therapy, brain-based neurorehabilitation efforts have begun to show promise in improving these deficits. The present study investigated the effectiveness of translingual neural stimulation (TLNS) on patients with mild-to-moderate TBI (mmTBI) and related brain connectivity using a resting-state functional connectivity (RSFC) approach. METHODS Resting-state images with 5-min on GE750 3T scanner were acquired from nine participants with mmTBI. Paired t-test was used for calculating changes in RSFC and behavioral scores before and after the TLNS intervention. The balance and movement performances related to mmTBI were evaluated by Sensory Organization Test (SOT) and Dynamic Gait Index (DGI). RESULTS Compared to pre-TLNS intervention, significant behavioral changes in SOT and DGI were observed. The analysis revealed increased RSFC between the left postcentral gyrus and left inferior parietal lobule and left Brodmann Area 40, as well as the increased RSFC between the right culmen and right declive, indicating changes due to TLNS treatment. However, there were no correlations between the sensory/somatomotor (or visual or cerebellar) network and SOT/DGI behavioral performance. CONCLUSIONS Although the limited sample size may have led to lack of significant correlations with functional assessments, these results provide preliminary evidence that TLNS in conjunction with physical therapy can induce brain plasticity in TBI patients with balance and movement deficits.
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Affiliation(s)
- Jiancheng Hou
- Research Center for Cross‐Straits Cultural DevelopmentFujian Normal UniversityFuzhouChina,Department of Radiology, School of Medicine and Public HealthUniversity of Wisconsin–MadisonMadisonWisconsinUSA
| | | | - Daniel Chu
- Department of Radiology, School of Medicine and Public HealthUniversity of Wisconsin–MadisonMadisonWisconsinUSA
| | - Veena A. Nair
- Department of Radiology, School of Medicine and Public HealthUniversity of Wisconsin–MadisonMadisonWisconsinUSA
| | - Yuri Danilov
- Department of KinesiologyUniversity of Wisconsin–MadisonMadisonWisconsinUSA
| | - Kurt A. Kaczmarek
- Department of KinesiologyUniversity of Wisconsin–MadisonMadisonWisconsinUSA
| | - Beth Meyerand
- Department of Biomedical EngineeringUniversity of Wisconsin–MadisonMadisonWisconsinUSA
| | - Mitchell Tyler
- Department of KinesiologyUniversity of Wisconsin–MadisonMadisonWisconsinUSA,Department of Biomedical EngineeringUniversity of Wisconsin–MadisonMadisonWisconsinUSA
| | - Vivek Prabhakaran
- Department of Radiology, School of Medicine and Public HealthUniversity of Wisconsin–MadisonMadisonWisconsinUSA
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Measuring threshold and latency of motion perception on a swinging bed. PLoS One 2021; 16:e0252914. [PMID: 34242212 PMCID: PMC8270192 DOI: 10.1371/journal.pone.0252914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 05/26/2021] [Indexed: 11/19/2022] Open
Abstract
Introduction Our objective was to develop and to evaluate a system to measure latency and threshold of pendular motion perception based on a swinging bed. Materials and methods This prospective study included 30 healthy adults (age: 32 ± 12 years). All subjects were tested twice with a 10 min. interval. A second trial was conducted 2 to 15 days after. A rehabilitation swinging bed was connected to an electronic device emitting a beep at the beginning of each oscillation phase with an adjustable time lag. Subjects were blindfolded and auditory cues other than the beep were minimized. The acceleration threshold was measured by letting the bed oscillate freely until a natural break and asking the patient when he did not perceive any motion. The perception latency was determined by asking the patient to indicate whether the beep and the peak of each oscillation were synchronous. The time lag between sound and peak of the head position was swept from -750 to +750 ms by 50 ms increments. Results The mean acceleration threshold was 9.2±4.60 cm/s2. The range width of the synchronous perception interval was estimated as 535±190 ms. The point of subjective synchronicity defined as the center of this interval was -195±106 ms (n = 30). The test-retest evaluation in the same trial showed an acceptable reproducibility for the acceleration threshold and good to excellent for all parameters related to sound-movement latency. Conclusion Swinging bed combined to sound stimulation can provide reproducible information on movement perception in a simple and non-invasive manner with highly reproducible results.
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Malmström EM, Ekvall Hansson E, Hafström A, Magnusson M, Fransson PA. Co-morbidities to Vestibular Impairments-Some Concomitant Disorders in Young and Older Adults. Front Neurol 2021; 11:609928. [PMID: 33584509 PMCID: PMC7873354 DOI: 10.3389/fneur.2020.609928] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 12/21/2020] [Indexed: 01/14/2023] Open
Abstract
Background: Dizziness and pain are common complaints that often appear concomitantly, with or without a causal relationship. However, these symptoms might maintain and exacerbate each other and other co-morbidities. Therefore, adequate rehabilitation may have to include an expanded focus on other deficits and preconditions, especially in older adults and in patients. Objective: To understand how frequently vestibular dysfunction coincided with medical conditions and aging, we studied two categories: Study 1: patients referred to a vestibular unit and Study 2: senior members in a fitness association. Method: Study 1: 49 patients [34 females/15 males; mean age 52 years (SEM 2.0)] seeking health care for balance disorders and vestibular deficits were asked in questionnaires about their perception of dizziness and pain, and emotional and functional strains. Study 2: 101 senior members in a fitness association [91 females/10 males; mean age 75 years (SEM 0.6)], were assessed for vestibular and balance deficits and for any co-morbidities. The participants were monitored for falls for 12 months after the initial assessments. Result: Study 1: Co-morbidity often existed between dizziness and pain (65%). The patients reported high emotional and functional strain related to their dizziness and pain. Patients older than 60 years reported longer durations of pain (p ≤ 0.028) but less emotional strain (p = 0.036), compared to younger patients. Study 2: 84% of the participants had a vestibular impairment, often without noticing any symptoms. Furthermore, 40% reported cardiovascular illnesses, 12% musculoskeletal disorders, and 63% reported other medical conditions. Forty-two percent experienced falls within 1 year after the initial assessments (thereof 42% in the group with vestibular deficits and 38% in the group without vestibular deficits). Conclusion: To enhance and preserve postural control, both in patients with vestibular deficits and in older adults, we suggest an expanded clinical perspective. Hence, we recommend detailed examinations of the vestibular system but simultaneously probing for possible co-morbidities. Since aging often entails deterioration of multimodal processes related to maintained mobility and postural stability, our results add focus on the importance of addressing balance disorders together with additional medical conditions.
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Affiliation(s)
- Eva-Maj Malmström
- Department of Clinical Sciences, Section of Otorhinolaryngology, Lund University, Lund, Sweden.,Department of Neurosurgery and Pain Rehabilitation, Skåne University Hospital, Lund, Sweden
| | | | - Anna Hafström
- Department of Clinical Sciences, Section of Otorhinolaryngology, Lund University, Lund, Sweden
| | - Måns Magnusson
- Department of Clinical Sciences, Section of Otorhinolaryngology, Lund University, Lund, Sweden
| | - Per-Anders Fransson
- Department of Clinical Sciences, Section of Otorhinolaryngology, Lund University, Lund, Sweden
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Noohi F, Kinnaird C, De Dios Y, Kofman IS, Wood SJ, Bloomberg J, Mulavara A, Sienko KH, Polk TA, Seidler RD. Age Differences in Vestibular Brain Connectivity Are Associated With Balance Performance. Front Aging Neurosci 2020; 12:566331. [PMID: 33312123 PMCID: PMC7703342 DOI: 10.3389/fnagi.2020.566331] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 10/27/2020] [Indexed: 11/26/2022] Open
Abstract
Visual and auditory brain network connectivity decline with age, but less is known about age effects on vestibular functional connectivity and its association with behavior. We assessed age differences in the connectivity of the vestibular cortex with other sensory brain regions, both during rest and during vestibular stimulation. We then assessed the relationship between vestibular connectivity and postural stability. A sample of seventeen young and fifteen older adults participated in our study. We assessed the amount of body sway in performing the Romberg balance task, with degraded somatosensory and visual inputs. The results showed no significant difference in balance performance between age groups. However, functional connectivity analyses revealed a main effect of age and condition, suggesting that vestibular connectivity was higher in young adults than older adults, and vestibular connectivity increased from resting state to stimulation trials. Surprisingly, young adults who exhibited higher connectivity during stimulation also had greater body sway. This suggests that young adults who exhibit better balance are those who respond more selectively to vestibular inputs. This correlation is non-significant in older adults, suggesting that the relationship between vestibular functional connectivity and postural stability differs with age.
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Affiliation(s)
- Fatemeh Noohi
- Department of Kinesiology, University of Michigan, Ann Arbor, MI, United States.,Department of Psychology, University of Michigan, Ann Arbor, MI, United States
| | - Catherine Kinnaird
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
| | | | | | - Scott J Wood
- NASA Johnson Space Center, Houston, TX, United States
| | | | | | - Kathleen H Sienko
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
| | - Thad A Polk
- Department of Psychology, University of Michigan, Ann Arbor, MI, United States
| | - Rachael D Seidler
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, United States
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Boegle R, Kirsch V, Gerb J, Dieterich M. Modulatory effects of magnetic vestibular stimulation on resting-state networks can be explained by subject-specific orientation of inner-ear anatomy in the MR static magnetic field. J Neurol 2020; 267:91-103. [PMID: 32529576 PMCID: PMC7718185 DOI: 10.1007/s00415-020-09957-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 05/27/2020] [Accepted: 05/28/2020] [Indexed: 12/26/2022]
Abstract
Strong static magnetic fields, as used in magnetic resonance imaging (MRI), stimulate the vestibular inner ear leading to a state of imbalance within the vestibular system that causes nystagmus. This magnetic vestibular stimulation (MVS) also modulates fluctuations of resting-state functional MRI (RS-fMRI) networks. MVS can be explained by a Lorentz force model, indicating that MVS is the result of the interaction of the static magnetic field strength and direction (called "B0 magnetic field" in MRI) with the inner ear's continuous endolymphatic ionic current. However, the high variability between subjects receiving MVS (measured as nystagmus slow-phase velocity and RS-fMRI amplitude modulations) despite matching head position, remains to be explained. Furthermore, within the imaging community, an "easy-to-acquire-and-use" proxy accounting for modulatory MVS effects in RS-fMRI fluctuations is needed. The present study uses MRI data of 60 healthy volunteers to examine the relationship between RS-fMRI fluctuations and the individual orientation of inner-ear anatomy within the static magnetic field of the MRI. The individual inner-ear anatomy and orientation were assessed via high-resolution anatomical CISS images and related to fluctuations of RS-fMRI networks previously associated with MVS. More specifically, we used a subject-specific proxy for MVS (pMVS) that corresponds to the orientation of the individual inner-ear anatomy within the static magnetic field direction (also called "z-direction" in MR imaging). We found that pMVS explained a considerable fraction of the total variance in RS-fMRI fluctuations (for instance, from 11% in the right cerebellum up to 36% in the cerebellar vermis). In addition to pMVS, we examined the angle of Reid's plane, as determined from anatomical imaging as an alternative and found that this angle (with the same sinus transformation as for pMVS) explained considerably less variance, e.g., from 2 to 16%. In our opinion, an excess variability due to MVS should generally be addressed in fMRI research analogous to nuisance regression for movement, pulsation, and respiration effects. We suggest using the pMVS parameter to deal with modulations of RS-fMRI fluctuations due to MVS. MVS-induced variance can easily be accounted by using high-resolution anatomical imaging of the inner ear and including the proposed pMVS parameter in fMRI group-level analysis.
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Affiliation(s)
- R Boegle
- Department of Neurology, University Hospital, Ludwig-Maximilians-Universität München, Marchioninistraße 15, 81377, Munich, Germany.
- German Center for Vertigo and Balance Disorders DSGZ-IFB LMU, University Hospital, Ludwig-Maximilians-Universität, Munich, Germany.
| | - V Kirsch
- Department of Neurology, University Hospital, Ludwig-Maximilians-Universität München, Marchioninistraße 15, 81377, Munich, Germany
- Graduate School of Systemic Neuroscience (GSN), Ludwig-Maximilians-Universität, Munich, Germany
- German Center for Vertigo and Balance Disorders DSGZ-IFB LMU, University Hospital, Ludwig-Maximilians-Universität, Munich, Germany
| | - J Gerb
- Department of Neurology, University Hospital, Ludwig-Maximilians-Universität München, Marchioninistraße 15, 81377, Munich, Germany
| | - M Dieterich
- Department of Neurology, University Hospital, Ludwig-Maximilians-Universität München, Marchioninistraße 15, 81377, Munich, Germany
- Graduate School of Systemic Neuroscience (GSN), Ludwig-Maximilians-Universität, Munich, Germany
- German Center for Vertigo and Balance Disorders DSGZ-IFB LMU, University Hospital, Ludwig-Maximilians-Universität, Munich, Germany
- Munich Cluster for Systems Neurology (Synergy), Munich, Germany
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Direct comparison of activation maps during galvanic vestibular stimulation: A hybrid H2[15 O] PET-BOLD MRI activation study. PLoS One 2020; 15:e0233262. [PMID: 32413079 PMCID: PMC7228124 DOI: 10.1371/journal.pone.0233262] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Accepted: 05/01/2020] [Indexed: 12/17/2022] Open
Abstract
Previous unimodal PET and fMRI studies in humans revealed a reproducible vestibular brain activation pattern, but with variations in its weighting and expansiveness. Hybrid studies minimizing methodological variations at baseline conditions are rare and still lacking for task-based designs. Thus, we applied for the first time hybrid 3T PET-MRI scanning (Siemens mMR) in healthy volunteers using galvanic vestibular stimulation (GVS) in healthy volunteers in order to directly compare H215O-PET and BOLD MRI responses. List mode PET acquisition started with the injection of 750 MBq H215O simultaneously to MRI EPI sequences. Group-level statistical parametric maps were generated for GVS vs. rest contrasts of PET, MR-onset (event-related), and MR-block. All contrasts showed a similar bilateral vestibular activation pattern with remarkable proximity of activation foci. Both BOLD contrasts gave more bilateral wide-spread activation clusters than PET; no area showed contradictory signal responses. PET still confirmed the right-hemispheric lateralization of the vestibular system, whereas BOLD-onset revealed only a tendency. The reciprocal inhibitory visual-vestibular interaction concept was confirmed by PET signal decreases in primary and secondary visual cortices, and BOLD-block decreases in secondary visual areas. In conclusion, MRI activation maps contained a mixture of CBF measured using H215O-PET and additional non-CBF effects, and the activation-deactivation pattern of the BOLD-block appears to be more similar to the H215O-PET than the BOLD-onset.
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11
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Effects of perceptible and imperceptible galvanic vestibular stimulation on the postural control of patients with bilateral vestibulopathy. J Neurol 2020; 267:2383-2397. [DOI: 10.1007/s00415-020-09852-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/17/2020] [Accepted: 04/18/2020] [Indexed: 01/01/2023]
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Helmchen C, Machner B, Rother M, Spliethoff P, Göttlich M, Sprenger A. Effects of galvanic vestibular stimulation on resting state brain activity in patients with bilateral vestibulopathy. Hum Brain Mapp 2020; 41:2527-2547. [PMID: 32103579 PMCID: PMC7267973 DOI: 10.1002/hbm.24963] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 02/03/2020] [Accepted: 02/11/2020] [Indexed: 01/04/2023] Open
Abstract
We examined the effect of galvanic vestibular stimulation (GVS) on resting state brain activity using fMRI (rs‐fMRI) in patients with bilateral vestibulopathy. Based on our previous findings, we hypothesized that GVS, which excites the vestibular nerve fibers, (a) increases functional connectivity in temporoparietal regions processing vestibular signals, and (b) alleviates abnormal visual–vestibular interaction. Rs‐fMRI of 26 patients and 26 age‐matched healthy control subjects was compared before and after GVS. The stimulation elicited a motion percept in all participants. Using different analyses (degree centrality, DC; fractional amplitude of low frequency fluctuations [fALFF] and seed‐based functional connectivity, FC), group comparisons revealed smaller rs‐fMRI in the right Rolandic operculum of patients. After GVS, rs‐fMRI increased in the right Rolandic operculum in both groups and in the patients' cerebellar Crus 1 which was related to vestibular hypofunction. GVS elicited a fALFF increase in the visual cortex of patients that was inversely correlated with the patients' rating of perceived dizziness. After GVS, FC between parietoinsular cortex and higher visual areas increased in healthy controls but not in patients. In conclusion, short‐term GVS is able to modulate rs‐fMRI in healthy controls and BV patients. GVS elicits an increase of the reduced rs‐fMRI in the patients' right Rolandic operculum, which may be an important contribution to restore the disturbed visual–vestibular interaction. The GVS‐induced changes in the cerebellum and the visual cortex were associated with lower dizziness‐related handicaps in patients, possibly reflecting beneficial neural plasticity that might subserve visual–vestibular compensation of deficient self‐motion perception.
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Affiliation(s)
- Christoph Helmchen
- Department of Neurology, University Hospitals Schleswig-Holstein, Lübeck, Germany
| | - Björn Machner
- Department of Neurology, University Hospitals Schleswig-Holstein, Lübeck, Germany
| | - Matthias Rother
- Department of Neurology, University Hospitals Schleswig-Holstein, Lübeck, Germany
| | - Peer Spliethoff
- Department of Neurology, University Hospitals Schleswig-Holstein, Lübeck, Germany
| | - Martin Göttlich
- Department of Neurology, University Hospitals Schleswig-Holstein, Lübeck, Germany
| | - Andreas Sprenger
- Department of Neurology, University Hospitals Schleswig-Holstein, Lübeck, Germany.,Institute of Psychology II, University of Lübeck, Lübeck, Germany
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Noohi F, Kinnaird C, De Dios Y, Kofman I, Wood SJ, Bloomberg JJ, Mulavara AP, Sienko KH, Polk TA, Seidler RD. Deactivation of somatosensory and visual cortices during vestibular stimulation is associated with older age and poorer balance. PLoS One 2019; 14:e0221954. [PMID: 31513630 PMCID: PMC6742389 DOI: 10.1371/journal.pone.0221954] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 08/19/2019] [Indexed: 12/11/2022] Open
Abstract
Aging is associated with peripheral and central declines in vestibular processing and postural control. Here we used functional MRI to investigate age differences in neural vestibular representations in response to pneumatic tap stimulation. We also measured the amount of body sway in multiple balance tasks outside of the MRI scanner to assess the relationship between individuals' balance ability and their vestibular neural response. We found a general pattern of activation in canonical vestibular cortex and deactivation in cross modal sensory regions in response to vestibular stimulation. We found that activation amplitude of the vestibular cortex was correlated with age, with younger individuals exhibiting higher activation. Deactivation of visual and somatosensory regions increased with age and was associated with poorer balance. The results demonstrate that brain activations and deactivations in response to vestibular stimuli are correlated with balance, and the pattern of these correlations varies with age. The findings also suggest that older adults exhibit less sensitivity to vestibular stimuli, and may compensate by differentially reweighting visual and somatosensory processes.
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Affiliation(s)
- Fatemeh Noohi
- Department of Kinesiology, University of Michigan, Ann Arbor, MI, United States of America
- Department of Psychology, University of Michigan, Ann Arbor, MI, United States of America
- * E-mail:
| | - Catherine Kinnaird
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
| | | | - Igor Kofman
- KBRwyle, Houston, TX, United States of America
| | - Scott J. Wood
- NASA Johnson Space Center, Houston, TX, United States of America
| | | | | | - Kathleen H. Sienko
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
| | - Thad A. Polk
- Department of Psychology, University of Michigan, Ann Arbor, MI, United States of America
| | - Rachael D. Seidler
- Department of Applied Physiology & Kinesiology, University of Florida, Gainesville, FL, United States of America
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Helmchen C, Rother M, Spliethoff P, Sprenger A. Increased brain responsivity to galvanic vestibular stimulation in bilateral vestibular failure. NEUROIMAGE-CLINICAL 2019; 24:101942. [PMID: 31382239 PMCID: PMC6690736 DOI: 10.1016/j.nicl.2019.101942] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 05/31/2019] [Accepted: 07/17/2019] [Indexed: 01/30/2023]
Abstract
In this event-related functional magnetic resonance imaging (fMRI) study we investigated how the brain of patients with bilateral vestibular failure (BVF) responds to vestibular stimuli. We used imperceptible noisy galvanic vestibular stimulation (GVS) and perceptible bi-mastoidal GVS intensities and related the corresponding brain activity to the evoked motion perception. In contrast to caloric irrigation, GVS stimulates the vestibular organ at its potentially intact afferent nerve site. Motion perception thresholds and cortical responses were compared between 26 BVF patients to 27 age-matched healthy control participants. To identify the specificity of vestibular cortical responses we used a parametric design with different stimulus intensities (noisy imperceptible, low perceptible, high perceptible) allowing region-specific stimulus response functions. In a 2 × 3 flexible factorial design all GVS-related brain activities were contrasted with a sham condition that did not evoke perceived motion. Patients had a higher motion perception threshold and rated the vestibular stimuli higher than the healthy participants. There was a stimulus intensity related and region-specific increase of activity with steep stimulus response functions in parietal operculum (e.g. OP2), insula, superior temporal gyrus, early visual cortices (V3) and cerebellum while activity in the hippocampus and intraparietal sulcus did not correlate with vestibular stimulus intensity. Using whole brain analysis, group comparisons revealed increased brain activity in early visual cortices (V3) and superior temporal gyrus of patients but there was no significant interaction, i.e. stimulus-response function in these regions were still similar in both groups. Brain activity in these regions during (high)GVS increased with higher dizziness-related handicap scores but was not related to the degree of vestibular impairment or disease duration. nGVS did not evoke cortical responses in any group. Our data indicate that perceptible GVS-related cortical responsivity is not diminished but increased in multisensory (visual-vestibular) cortical regions despite bilateral failure of the peripheral vestibular organ. The increased activity in early visual cortices (V3) and superior temporal gyrus of BVF patients has several potential implications: (i) their cortical reciprocal inhibitory visuo-vestibular interaction is dysfunctional, (ii) it may contribute to the visual dependency of BVF patients, and (iii) it needs to be considered when BVF patients receive peripheral vestibular stimulation devices, e.g. vestibular implants or portable GVS devices. Imperceptible nGVS did not elicit cortical brain responses making it unlikely that the reported balance improvement of BVF by nGVS is mediated by cortical mechanisms. Responsivity to galvanic vestibular stimuli is increased in the visual and superior temporal Cortex of patients with bilateral vestibulopathy. Group differences correlated with clinical scores of disability. Dysfunctional visual-vestibular interaction is proposed.
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Affiliation(s)
- Christoph Helmchen
- Department of Neurology, University of Lübeck, University Hospitals Schleswig-Holstein, Campus Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany.
| | - Matthias Rother
- Department of Neurology, University of Lübeck, University Hospitals Schleswig-Holstein, Campus Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany
| | - Peer Spliethoff
- Department of Neurology, University of Lübeck, University Hospitals Schleswig-Holstein, Campus Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany
| | - Andreas Sprenger
- Department of Neurology, University of Lübeck, University Hospitals Schleswig-Holstein, Campus Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany; Institute of Psychology II, University of Luebeck, Germany
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15
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Postural control during galvanic vestibular stimulation in patients with persistent perceptual-postural dizziness. J Neurol 2019; 266:1236-1249. [PMID: 30809703 DOI: 10.1007/s00415-019-09255-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 02/15/2019] [Accepted: 02/18/2019] [Indexed: 12/15/2022]
Abstract
Over the past years galvanic vestibular stimulation (GVS) has been increasingly applied to stimulate the vestibular system in health and disease, but not in patients with persistent postural-perceptual dizziness (PPPD) yet. We functionally tested motion perception thresholds and postural responses to imperceptible noisy (nGVS) and perceptible bimastoidal GVS intensities in patients with PPPD with normal vestibulo-ocular reflexes. We hypothesized that GVS destabilizes PPPD patients under simple postural conditions stronger compared to healthy controls. They were compared to healthy subjects under several conditions each with the eyes open and closed: baseline with firm platform support, standing on foam and cognitive demand (count backward). Low and high GVS intensities (range 0.8-2.8 mA) were applied according to the individual thresholds and compared with no GVS. PPPD patients showed a reduced perception threshold to GVS compared to healthy control subjects. Median postural sway speed increased with stimulus intensity and on eye closure, but there was no group difference, irrespective of the experimental condition. Romberg's ratio was consistently lower during nGVS than in all other conditions. Group-related dissociable effects were found with the eyes closed in (i) the baseline condition in which high GVS elicited higher postural sway of PPPD patients and (ii) in the foam condition, with better postural stability of PPPD patients during perceptible GVS. Group and condition differences of postural control were neither related to anxiety nor depression scores. GVS may be helpful to identify thresholds of vestibular perception and to modulate vestibulo-spinal reflexes in PPPD, with dissociable effects with respect to perceptible and imperceptible stimuli. The sway increase in the baseline of PPPD may be related to an earlier transition from open- to closed-loop mode of postural control. In contrast, the smaller sway of PPPD in the foam condition under visual deprivation is in line with the known balance improvement under more demanding postural challenges in PPPD. It is associated with a prolonged transition from open- to closed-loop postural feedback control. It could also reflect a shift of intersensory weighting with a smaller dependence on proprioceptive feedback control in PPPD patients under complex tasks. In summary, GVS discloses differences between simple and complex balance tasks in PPPD.
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16
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Kirsch V, Boegle R, Keeser D, Kierig E, Ertl-Wagner B, Brandt T, Dieterich M. Handedness-dependent functional organizational patterns within the bilateral vestibular cortical network revealed by fMRI connectivity based parcellation. Neuroimage 2018; 178:224-237. [DOI: 10.1016/j.neuroimage.2018.05.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 05/02/2018] [Accepted: 05/05/2018] [Indexed: 12/19/2022] Open
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Paraskevoudi N, Balcı F, Vatakis A. "Walking" through the sensory, cognitive, and temporal degradations of healthy aging. Ann N Y Acad Sci 2018; 1426:72-92. [PMID: 29741265 DOI: 10.1111/nyas.13734] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 03/17/2018] [Accepted: 03/22/2018] [Indexed: 02/03/2023]
Abstract
As we age, there is a wide range of changes in motor, sensory, cognitive, and temporal processing due to alterations in the functioning of the central nervous and musculoskeletal systems. Specifically, aging is associated with degradations in gait; altered processing of the individual sensory systems; modifications in executive control, memory, and attention; and changes in temporal processing. These age-related alterations are often inter-related and have been suggested to result from shared neural substrates. Additionally, the overlap between these brain areas and those controlling walking raises the possibility of facilitating performance in several tasks by introducing protocols that can efficiently target all four domains. Attempts to counteract these negative effects of normal aging have been focusing on research to prevent falls and/or enhance cognitive processes, while ignoring the potential multisensory benefits accompanying old age. Research shows that the aging brain tends to increasingly rely on multisensory integration to compensate for degradations in individual sensory systems and for altered neural functioning. This review covers the age-related changes in the above-mentioned domains and the potential to exploit the benefits associated with multisensory integration in aging so as to improve one's mobility and enhance sensory, cognitive, and temporal processing.
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Affiliation(s)
- Nadia Paraskevoudi
- Multisensory and Temporal Processing Lab (MultiTimeLab), Department of History and Philosophy of Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Fuat Balcı
- Department of Psychology, Koç University, Istanbul, Turkey
| | - Argiro Vatakis
- Multisensory and Temporal Processing Lab (MultiTimeLab), Department of History and Philosophy of Science, National and Kapodistrian University of Athens, Athens, Greece
- Cognitive Systems Research Institute, Athens, Greece
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18
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Damulin IV. [Changes in walking in the elderly]. Zh Nevrol Psikhiatr Im S S Korsakova 2018; 118:100-104. [PMID: 29560950 DOI: 10.17116/jnevro201811821100-104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The article addresses gait disturbances in the elderly. It emphasizes that the system that maintains the balance in resting conditions and gait is based on the hierarchical principle and its function depends on the maintenance of integration between vestibular, visual and somatosensory information as well as on cognitive functions. Walking depends on the integrity of frontal-subcortical neuronal circles that support regulatory functions. The main pathogenetic mechanisms of age-related disturbances of balance and gait are a decrease in the efficacy of spinal motorneurons activation caused by Ia-afferentation, a decrease in cortical activation and excitability of corticospinal pathways and in the intensity of intracortical inhibition. The causes of age-related changes in walking are not confined to a single system (e.g., one sensory modality) but have a multisystem character and are involved in many structures. The author analyses the results of recent studies that use functional neuroimaging methods.
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Affiliation(s)
- I V Damulin
- Sechenov First Moscow State Medical University, Moscow, Russia
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19
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Vestibular perception thresholds tested by galvanic vestibular stimulation. J Neurol 2018; 265:54-56. [DOI: 10.1007/s00415-018-8808-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 02/21/2018] [Accepted: 02/23/2018] [Indexed: 11/27/2022]
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20
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Blini E, Tilikete C, Farnè A, Hadj-Bouziane F. Probing the role of the vestibular system in motivation and reward-based attention. Cortex 2018; 103:82-99. [PMID: 29574253 PMCID: PMC6002611 DOI: 10.1016/j.cortex.2018.02.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 02/07/2018] [Accepted: 02/07/2018] [Indexed: 01/31/2023]
Abstract
The vestibular system has widespread connections in the central nervous system. Several activation loci following vestibular stimulations have been notably reported in deep, limbic areas that are otherwise difficult to reach and modulate in healthy subjects. Following preliminary evidence, suggesting that such stimulations might affect mood and affective processing, we wondered whether the vestibular system is also involved in motivation. Evolutionary accounts suggest that visuo-vestibular mismatches might have a role in preventing the search for and exploitation of goods that previously resulted in aversive reactions, as they would be a fine warning signal which follows the contact with or ingestion of noxious neurotoxins. The first question was thus whether vestibular stimulation alters sensitivity to reward. Secondly, we sought to assess whether attention is allocated in space differently when cued by highly motivational stimuli, and if this interplay is further modulated by the vestibular system. In order to evaluate both motivational and attentional assets, we administered a Posner-like cueing task to 30 healthy subjects concurrently receiving sham or galvanic vestibular stimulation (GVS; Left-Anodal and Right-Anodal configurations). The participants had to discriminate targets appearing in either exogenously cued or uncued locations (50% validity); cues predicted the amount of points (0, 2, or 10) and thus money that they could earn for a correct response. The results highlight a robust inhibition of return (IOR) (faster responses for invalidly-cued targets) which was not modulated by different levels of reward or GVS. Across all stimulation sessions, rewards exerted a powerful beneficial effect over performance: reaction times were faster when rewards were at stake. However, this effect was largest in sham, but greatly reduced in GVS conditions, most notably with the Right-Anodal configuration. This is the first evidence for a decreased sensitivity to rewards causally induced by a perturbation of the vestibular system. While future studies will shed light on its neural underpinnings and clinical implications, here we argue that GVS could be a safe and promising way to enrich our understanding of reward processes and eventually tackle the management of patients with aberrant sensitivity to rewards.
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Affiliation(s)
- Elvio Blini
- Integrative Multisensory Perception Action & Cognition Team (ImpAct), INSERM U1028, CNRS UMR5292, Lyon Neuroscience Research Center (CRNL), Lyon, France; University of Lyon 1, Lyon, France.
| | - Caroline Tilikete
- Integrative Multisensory Perception Action & Cognition Team (ImpAct), INSERM U1028, CNRS UMR5292, Lyon Neuroscience Research Center (CRNL), Lyon, France; University of Lyon 1, Lyon, France; Hospices Civils de Lyon, Neuro-Ophthalmology and Neurocognition, Hôpital Neurologique Pierre Wertheimer, Bron, France
| | - Alessandro Farnè
- Integrative Multisensory Perception Action & Cognition Team (ImpAct), INSERM U1028, CNRS UMR5292, Lyon Neuroscience Research Center (CRNL), Lyon, France; University of Lyon 1, Lyon, France; Hospices Civils de Lyon, Neuro-Immersion & Mouvement et Handicap, Lyon, France
| | - Fadila Hadj-Bouziane
- Integrative Multisensory Perception Action & Cognition Team (ImpAct), INSERM U1028, CNRS UMR5292, Lyon Neuroscience Research Center (CRNL), Lyon, France; University of Lyon 1, Lyon, France.
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21
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Krause Neto W, Silva WDA, Ciena AP, de Souza RR, Anaruma CA, Gama EF. Aging Induces Changes in the Somatic Nerve and Postsynaptic Component without Any Alterations in Skeletal Muscles Morphology and Capacity to Carry Load of Wistar Rats. Front Neurosci 2017; 11:688. [PMID: 29326543 PMCID: PMC5741656 DOI: 10.3389/fnins.2017.00688] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 11/22/2017] [Indexed: 01/09/2023] Open
Abstract
The present study aimed to analyze the morphology of the peripheral nerve, postsynaptic compartment, skeletal muscles and weight-bearing capacity of Wistar rats at specific ages. Twenty rats were divided into groups: 10 months-old (ADULT) and 24 months-old (OLD). After euthanasia, we prepared and analyzed the tibial nerve using transmission electron microscopy and the soleus and plantaris muscles for cytofluorescence and histochemistry. For the comparison of the results between groups we used dependent and independent Student's t-test with level of significance set at p ≤ 0.05. For the tibial nerve, the OLD group presented the following alterations compared to the ADULT group: larger area and diameter of both myelinated fibers and axons, smaller area occupied by myelinated and unmyelinated axons, lower numerical density of myelinated fibers, and fewer myelinated fibers with normal morphology. Both aged soleus and plantaris end-plate showed greater total perimeter, stained perimeter, total area and stained area compared to ADULT group (p < 0.05). Yet, aged soleus end-plate presented greater dispersion than ADULT samples (p < 0.05). For the morphology of soleus and plantaris muscles, density of the interstitial volume was greater in the OLD group (p < 0.05). No statistical difference was found between groups in the weight-bearing tests. The results of the present study demonstrated that the aging process induces changes in the peripheral nerve and postsynaptic compartment without any change in skeletal muscles and ability to carry load in Wistar rats.
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Affiliation(s)
- Walter Krause Neto
- Laboratory of Morphoquantitative Studies and Immunohistochemistry, Department of Physical Education, São Judas Tadeu University, São Paulo, Brazil
| | - Wellington de Assis Silva
- Laboratory of Morphoquantitative Studies and Immunohistochemistry, Department of Physical Education, São Judas Tadeu University, São Paulo, Brazil
| | - Adriano P Ciena
- Laboratory of Morphology and Physical Activity, Department of Physical Education, São Paulo State University, Rio Claro, Brazil
| | - Romeu R de Souza
- Laboratory of Morphoquantitative Studies and Immunohistochemistry, Department of Physical Education, São Judas Tadeu University, São Paulo, Brazil
| | - Carlos A Anaruma
- Laboratory of Morphology and Physical Activity, Department of Physical Education, São Paulo State University, Rio Claro, Brazil
| | - Eliane F Gama
- Laboratory of Morphoquantitative Studies and Immunohistochemistry, Department of Physical Education, São Judas Tadeu University, São Paulo, Brazil
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22
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Zu Eulenburg P, Ruehl RM, Runge P, Dieterich M. Ageing-related changes in the cortical processing of otolith information in humans. Eur J Neurosci 2017; 46:2817-2825. [PMID: 29057523 DOI: 10.1111/ejn.13755] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 10/12/2017] [Accepted: 10/12/2017] [Indexed: 12/15/2022]
Abstract
Acoustic short tone bursts (STB) trigger ocular and cervical vestibular-evoked myogenic potentials (oVEMPs/cVEMPs) by activating irregular otolith afferents. Simultaneously, STBs introduce an artificial net acceleration signal of otolith origin into the vestibular network. VEMP parameters as diagnostic otolith processing markers have been shown to decline after the age of thirty. To delineate the differential effects of healthy ageing on the cortical vestibular subnetwork processing otolith information, we measured cVEMPs and the differential effects of unilateral STB in three age groups (20-40, 40-60 and 60+; n = 42) using functional neuroimaging. STB evoked responses in the main vestibular hubs in the parieto-opercular cortex. Whereas cVEMP amplitudes declined linearly with age, analysis of the BOLD response size depicted a u-shaped curve. Vestibular perception of the otolith stimulus on the other hand remained unchanged with age. Therefore, we propose that the comparably larger BOLD responses past the age of sixty could reflect a mechanism of central sensitisation for otolith perception to counterbalance the concurrent peripheral vestibular and somatosensory function decline.
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Affiliation(s)
- Peter Zu Eulenburg
- German Center for Vertigo and Balance Disorders, University Hospital, Ludwig-Maximilians University, Feodor-Lynen-Str. 19, Munich, D-81377, Germany.,Department of Neurology, University Hospital, Ludwig-Maximilians University, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.,Department of Neuroradiology, Johannes Gutenberg-University, Mainz, Germany
| | - Ria Maxine Ruehl
- German Center for Vertigo and Balance Disorders, University Hospital, Ludwig-Maximilians University, Feodor-Lynen-Str. 19, Munich, D-81377, Germany.,Department of Neurology, University Hospital, Ludwig-Maximilians University, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Pia Runge
- Department of Neuroradiology, Johannes Gutenberg-University, Mainz, Germany
| | - Marianne Dieterich
- German Center for Vertigo and Balance Disorders, University Hospital, Ludwig-Maximilians University, Feodor-Lynen-Str. 19, Munich, D-81377, Germany.,Department of Neurology, University Hospital, Ludwig-Maximilians University, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
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23
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Mastoid vibration affects dynamic postural control during gait in healthy older adults. Sci Rep 2017; 7:41547. [PMID: 28128341 PMCID: PMC5269701 DOI: 10.1038/srep41547] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 12/22/2016] [Indexed: 01/14/2023] Open
Abstract
Vestibular disorders are difficult to diagnose early due to the lack of a systematic assessment. Our previous work has developed a reliable experimental design and the result shows promising results that vestibular sensory input while walking could be affected through mastoid vibration (MV) and changes are in the direction of motion. In the present paper, we wanted to extend this work to older adults and investigate how manipulating sensory input through mastoid vibration (MV) could affect dynamic postural control during walking. Three levels of MV (none, unilateral, and bilateral) applied via vibrating elements placed on the mastoid processes were combined with the Locomotor Sensory Organization Test (LSOT) paradigm to challenge the visual and somatosensory systems. We hypothesized that the MV would affect sway variability during walking in older adults. Our results revealed that MV significantly not only increased the amount of sway variability but also decreased the temporal structure of sway variability only in anterior-posterior direction. Importantly, the bilateral MV stimulation generally produced larger effects than the unilateral. This is an important finding that confirmed our experimental design and the results produced could guide a more reliable screening of vestibular system deterioration.
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24
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Arshad Q, Seemungal BM. Age-Related Vestibular Loss: Current Understanding and Future Research Directions. Front Neurol 2016; 7:231. [PMID: 28066316 PMCID: PMC5165261 DOI: 10.3389/fneur.2016.00231] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 12/02/2016] [Indexed: 01/23/2023] Open
Abstract
The vestibular system sub-serves a number of reflex and perceptual functions, comprising the peripheral apparatus, the vestibular nerve, the brainstem and cerebellar processing circuits, the thalamic relays, and the vestibular cerebral cortical network. This system provides signals of self-motion, important for gaze and postural control, and signals of traveled distance, for spatial orientation, especially in the dark. Current evidence suggests that certain aspects of this multi-faceted system may deteriorate with age and sometimes with severe consequences, such as falls. Often the deterioration in vestibular functioning relates to how the signal is processed by brain circuits rather than an impairment in the sensory transduction process. We review current data concerning age-related changes in the vestibular system, and how this may be important for clinicians dealing with balance disorders.
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Affiliation(s)
- Qadeer Arshad
- Division of Brain Sciences, Imperial College London , London , UK
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25
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Smith PF. Age-Related Neurochemical Changes in the Vestibular Nuclei. Front Neurol 2016; 7:20. [PMID: 26973593 PMCID: PMC4776078 DOI: 10.3389/fneur.2016.00020] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 02/09/2016] [Indexed: 12/18/2022] Open
Abstract
There is evidence that the normal aging process is associated with impaired vestibulo-ocular reflexes (VOR) and vestibulo-spinal reflexes, causing reduced visual acuity and postural instability. Nonetheless, the available evidence is not entirely consistent, especially with respect to the VOR. Some recent studies have reported that VOR gain can be intact even above 80 years of age. Similarly, although there is evidence for age-related hair cell loss and neuronal loss in Scarpa's ganglion and the vestibular nucleus complex (VNC), it is not entirely consistent. Whatever structural and functional changes occur in the VNC as a result of aging, either to cause vestibular impairment or to compensate for it, neurochemical changes must underlie them. However, the neurochemical changes that occur in the VNC with aging are poorly understood because the available literature is very limited. This review summarizes and critically evaluates the available evidence relating to the noradrenaline, serotonin, dopamine, glutamate, GABA, glycine, and nitric oxide neurotransmitter systems in the aging VNC. It is concluded that, at present, it is difficult, if not impossible, to relate the neurochemical changes observed to the function of specific VNC neurons and whether the observed changes are the cause of a functional deficit in the VNC or an effect of it. A better understanding of the neurochemical changes that occur during aging may be important for the development of potential drug treatments for age-related vestibular disorders. However, this will require the use of more sophisticated methodology such as in vivo microdialysis with single neuron recording and perhaps new technologies such as optogenetics.
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Affiliation(s)
- Paul F Smith
- Department of Pharmacology and Toxicology, School of Medical Sciences and Brain Health Research Centre, University of Otago , Dunedin , New Zealand
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