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Marianne Dieterich - One of the best experts on this subject based on the ideXlab platform.
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the human Vestibular Cortex
ScienceOpen Posters, 2020Co-Authors: Peter Zu Eulenburg, Marianne Dieterich, Thomas Stephan, Ria Maxine RuehlAbstract:Aim: The cortical representations for almost all senses (touch, pain, sound, vision and smell) haven been robustly mapped in humans with functional neuroimaging. But the majority of cerebral regions receiving Vestibular information originating from our so-called sixth sense have evaded a definitive localization for more than two decades now. Neuron recordings and tracer studies in several primate species had previously established a cortical Vestibular network of at least seven (maximum ten) regions per hemisphere [ 1 , 2 ]. Up to now, several confounders impeded the delineation of a human Vestibular Cortex. These included somatosensory confounders, head motion artifacts, difficulties in evoking an intense Vestibular percept and spatio-temporal limitations of fMRI. Aim of our fMRI study was to finally localize all cortical Vestibular regions known from other primate species in humans. In a subsequent step we also intended to perform an internal replication of our findings. Methods: We examined 60 stimulus-naive, right-handed healthy subjects (33 F; mean age 27 years) in two separate groups (n=30) spanning a cultural background of 17 different nationalities. Sinusoidal low-frequency galvanic Vestibular stimulation (GVS) (0.875Hz, 3mA) after local anaesthesia of the postauricular region was conducted via bimastoidal electrodes to elicit naturalistic Vestibular sensations. Structural and functional images were obtained in a clinical 3T scanner (Siemens Magnetom Skyra) equipped with a 64-channel head and neck coil. The protocol included a resting-state and a GVS session consisting of a prescan-normalized T2*-weighted EPI sequence (TR 0.7s, 56 interleaved slices, multi-band factor 6, 2.5mm in-plane resolution, slice thickness 2.5 mm), as well as a structural MPRAGE sequence. Data analysis was performed using SPM12 (Version 6407 Wellcome Department of Imaging Neuroscience, UK) and the SPM Anatomy toolbox (Version 2.2c) after standard preprocessing including DARTEL-based normalization[ 3 ]. Results were considered significant at FDR p<0.01 (corrected at voxel level). Results: Controlling and accounting for somatosensory, nociceptive and salience effects we were able to delineate and identify nine cortical homologues to known Vestibular representations in non-human primates. Aside from the cerebellar nodule and uvula we found the cytoarchitectonic area OP2 in the parietal operculum to be the human core equivalent to the parieto-insular Vestibular region PIVC. Monkey visual posterior sylvian area (VPS) could be mapped to cytoarchitectonic area PFcm whereas area 7 is probably located in the human inferior parietal lobule (cytoarchitectonic area PF). We could also identify the ventral intraparietal area (VIP) in the intraparietal sulcus (cytoarchitectonic area hIP3) as well as areas 2v and 3aV. The area cingulate sulcus visual (CSv) was found to be the Vestibular cingulate (VC) region known from non-human primates. We found a strong Vestibular response in already established area MST und could map monkey area 6 to a lateral premotor region in humans. The Vestibular reponse found in the periarcuate Cortex in monkeys is probably reflected in a paramedian human activation in the supplementary motor area. All of these findings could be replicated internally in the second independent cohort. Conclusion: We were able to robustly delineate and map the human Vestibular Cortex. We identified ten cortical homologue Vestibular regions known from non-human primates. The response patterns to the confounder-minimised GVS protocol show that the cortical core Vestibular network in humans is probably represented by areas OP2 (PIVC), MST, PFcm (VPS), PF (area 7) and CSv (VC). References: This work was supported by the Federal Ministry of Education and Research (BMBF 01 EO 0901).
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The human Vestibular Cortex
2020Co-Authors: Peter Zu Eulenburg, Marianne Dieterich, Thomas Stephan, Ria Maxine RuehlAbstract:Aim: The cortical representations for almost all senses (touch, pain, sound, vision and smell) haven been robustly mapped in humans with functional neuroimaging. But the majority of cerebral regions receiving Vestibular information originating from our so-called sixth sense have evaded a definitive localization for more than two decades now. Neuron recordings and tracer studies in several primate species had previously established a cortical Vestibular network of at least seven (maximum ten) regions per hemisphere [ 1 , 2 ]. Up to now, several confounders impeded the delineation of a human Vestibular Cortex. These included somatosensory confounders, head motion artifacts, difficulties in evoking an intense Vestibular percept and spatio-temporal limitations of fMRI. Aim of our fMRI study was to finally localize all cortical Vestibular regions known from other primate species in humans. In a subsequent step we also intended to perform an internal replication of our findings. Methods: We examined 60 stimulus-naive, right-handed healthy subjects (33 F; mean age 27 years) in two separate groups (n=30) spanning a cultural background of 17 different nationalities. Sinusoidal low-frequency galvanic Vestibular stimulation (GVS) (0.875Hz, 3mA) after local anaesthesia of the postauricular region was conducted via bimastoidal electrodes to elicit naturalistic Vestibular sensations. Structural and functional images were obtained in a clinical 3T scanner (Siemens Magnetom Skyra) equipped with a 64-channel head and neck coil. The protocol included a resting-state and a GVS session consisting of a prescan-normalized T2*-weighted EPI sequence (TR 0.7s, 56 interleaved slices, multi-band factor 6, 2.5mm in-plane resolution, slice thickness 2.5 mm), as well as a structural MPRAGE sequence. Data analysis was performed using SPM12 (Version 6407 Wellcome Department of Imaging Neuroscience, UK) and the SPM Anatomy toolbox (Version 2.2c) after standard preprocessing including DARTEL-based normalization[ 3 ]. Results were considered significant at FDR p
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Beyond binary parcellation of the Vestibular Cortex - A dataset.
Data in brief, 2019Co-Authors: Valerie Kirsch, T. Brandt, Rainer Boegle, Daniel Keeser, E. Kierig, Birgit Ertl-wagner, Marianne DieterichAbstract:The data-set presented in this data article is supplementary to the original publication, doi:10.1016/j.neuroimage.2018.05.018 (Kirsch et al., 2018). Named article describes handedness-dependent organizational patterns of functional subunits within the human Vestibular cortical network that were revealed by functional magnetic resonance imaging (fMRI) connectivity parcellation. 60 healthy volunteers (30 left-handed and 30 right-handed) were examined on a 3T MR scanner using resting state fMRI. The multisensory (non-binary) nature of the human (Vestibular) Cortex was addressed by using masked binary and non-binary variations of independent component analysis (ICA). The data have been made publicly available via github (https://github.com/RainerBoegle/BeyondBinaryParcellationData).
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Handedness-dependent functional organizational patterns within the bilateral Vestibular cortical network revealed by fMRI connectivity based parcellation.
NeuroImage, 2018Co-Authors: Valerie Kirsch, Thomas Brandt, Rainer Boegle, Daniel Keeser, E. Kierig, Birgit Ertl-wagner, Marianne DieterichAbstract:Current evidence points towards a Vestibular Cortex that involves a multisensory bilateral temporo-parietal-insular network with a handedness-dependent hemispheric lateralization. This study aimed to identify handedness-dependent organizational patterns of (lateralized and non-lateralized) functional subunits within the human Vestibular Cortex areas. 60 healthy volunteers (30 left-handed and 30 right-handed) were examined on a 3T MR scanner using resting state functional MRI (fMRI). The data was analyzed in four major steps using a functional connectivity based parcellation (fCBP) approach: (1) independent component analysis (ICA) on a whole brain level to identify different resting state networks (RSN); (2) creation of a Vestibular informed mask from four whole brain ICs that included reference coordinates of the Vestibular network extracted from meta-analyses of Vestibular neuroimaging experiments; (3) Re-ICA confined to the Vestibular informed mask; (4) cross-correlation of the activated voxels within the Vestibular subunits (parcels) to each other (P-to-P) and to the whole-brain RSN (P-to-RSN). This approach disclosed handedness-dependency, inter-hemispheric symmetry, the scale of connectedness to major whole brain RSN and the grade of spatial overlap of voxels within parcels (common/unique) as meaningful discriminatory organizational categories within the Vestibular Cortex areas. This network consists of multiple inter-hemisphere symmetric (not lateralized), well-connected (many RSN-assignments) multisensory areas (or hubs; e.g., superior temporal gyrus, temporo-parietal intersection) organized around an asymmetric (lateralized, "dominant") and functionally more specialized (few RSN-assignments) core region in the parieto-insular Cortex. The latter is in the middle, posterior and inferior insula. In conclusion, the bilateral cortical Vestibular network contains not only a handedness-dependent lateralized central region concentrated in the right hemisphere in right-handers and left hemisphere in left-handers, but also surrounding inter-hemisphere symmetric multisensory Vestibular areas that seem to be functionally influenced by their neighboring sensory systems (e.g., temporo-parietal intersection by the visual system). One may speculate that the development of an asymmetrical organized Vestibular subsystem reflects a more recent phylogenetic evolution of various multisensory Vestibular functions. The right hemispheric dominance of spatial orientation and its disorders, spatial neglect and pusher syndrome, may serve as examples.
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the parietal lobe and the Vestibular system
Handbook of Clinical Neurology, 2018Co-Authors: Marianne Dieterich, Thomas BrandtAbstract:Abstract The Vestibular Cortex differs in various ways from other sensory cortices. It consists of a network of several distinct and separate temporoparietal areas. Its core region, the parietoinsular Vestibular Cortex (PIVC), is located in the posterior insula and retroinsular region and includes the parietal operculum. The entire network is multisensory (in particular, Vestibular, visual, and somatosensory). The peripheral and central Vestibular systems are bilaterally organized; there are various pontomesencephalic brainstem crossings and at least two transcallosal connections of both hemispheres, between the PIVC and the motion-sensitive visual Cortex areas, which also mediate Vestibular input. Structural and functional Vestibular dominance characterizes the right hemisphere in right-handers and the left hemisphere in left-handers. This explains why right-hemispheric lesions in right-handers more often generally cause hemispatial neglect and the pusher syndrome, both of which involve Vestibular function. Vestibular input also contributes to cognition and may determine individual lateralization of brain functions such as handedness. Bilateral organization is a major key to understanding cortical functions and disorders, for example, the visual–Vestibular interaction that occurs in spatial orientation. Although the Vestibular Cortex is represented in both hemispheres, there is only one global percept of body position and motion. The chiefly Vestibular aspects of the multiple functions and disorders of the parietal lobe dealt with in this chapter cannot be strictly separated from various multisensory Vestibular functions within the entire brain.
Thomas Brandt - One of the best experts on this subject based on the ideXlab platform.
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Handedness-dependent functional organizational patterns within the bilateral Vestibular cortical network revealed by fMRI connectivity based parcellation.
NeuroImage, 2018Co-Authors: Valerie Kirsch, Thomas Brandt, Rainer Boegle, Daniel Keeser, E. Kierig, Birgit Ertl-wagner, Marianne DieterichAbstract:Current evidence points towards a Vestibular Cortex that involves a multisensory bilateral temporo-parietal-insular network with a handedness-dependent hemispheric lateralization. This study aimed to identify handedness-dependent organizational patterns of (lateralized and non-lateralized) functional subunits within the human Vestibular Cortex areas. 60 healthy volunteers (30 left-handed and 30 right-handed) were examined on a 3T MR scanner using resting state functional MRI (fMRI). The data was analyzed in four major steps using a functional connectivity based parcellation (fCBP) approach: (1) independent component analysis (ICA) on a whole brain level to identify different resting state networks (RSN); (2) creation of a Vestibular informed mask from four whole brain ICs that included reference coordinates of the Vestibular network extracted from meta-analyses of Vestibular neuroimaging experiments; (3) Re-ICA confined to the Vestibular informed mask; (4) cross-correlation of the activated voxels within the Vestibular subunits (parcels) to each other (P-to-P) and to the whole-brain RSN (P-to-RSN). This approach disclosed handedness-dependency, inter-hemispheric symmetry, the scale of connectedness to major whole brain RSN and the grade of spatial overlap of voxels within parcels (common/unique) as meaningful discriminatory organizational categories within the Vestibular Cortex areas. This network consists of multiple inter-hemisphere symmetric (not lateralized), well-connected (many RSN-assignments) multisensory areas (or hubs; e.g., superior temporal gyrus, temporo-parietal intersection) organized around an asymmetric (lateralized, "dominant") and functionally more specialized (few RSN-assignments) core region in the parieto-insular Cortex. The latter is in the middle, posterior and inferior insula. In conclusion, the bilateral cortical Vestibular network contains not only a handedness-dependent lateralized central region concentrated in the right hemisphere in right-handers and left hemisphere in left-handers, but also surrounding inter-hemisphere symmetric multisensory Vestibular areas that seem to be functionally influenced by their neighboring sensory systems (e.g., temporo-parietal intersection by the visual system). One may speculate that the development of an asymmetrical organized Vestibular subsystem reflects a more recent phylogenetic evolution of various multisensory Vestibular functions. The right hemispheric dominance of spatial orientation and its disorders, spatial neglect and pusher syndrome, may serve as examples.
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the parietal lobe and the Vestibular system
Handbook of Clinical Neurology, 2018Co-Authors: Marianne Dieterich, Thomas BrandtAbstract:Abstract The Vestibular Cortex differs in various ways from other sensory cortices. It consists of a network of several distinct and separate temporoparietal areas. Its core region, the parietoinsular Vestibular Cortex (PIVC), is located in the posterior insula and retroinsular region and includes the parietal operculum. The entire network is multisensory (in particular, Vestibular, visual, and somatosensory). The peripheral and central Vestibular systems are bilaterally organized; there are various pontomesencephalic brainstem crossings and at least two transcallosal connections of both hemispheres, between the PIVC and the motion-sensitive visual Cortex areas, which also mediate Vestibular input. Structural and functional Vestibular dominance characterizes the right hemisphere in right-handers and the left hemisphere in left-handers. This explains why right-hemispheric lesions in right-handers more often generally cause hemispatial neglect and the pusher syndrome, both of which involve Vestibular function. Vestibular input also contributes to cognition and may determine individual lateralization of brain functions such as handedness. Bilateral organization is a major key to understanding cortical functions and disorders, for example, the visual–Vestibular interaction that occurs in spatial orientation. Although the Vestibular Cortex is represented in both hemispheres, there is only one global percept of body position and motion. The chiefly Vestibular aspects of the multiple functions and disorders of the parietal lobe dealt with in this chapter cannot be strictly separated from various multisensory Vestibular functions within the entire brain.
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Schematic drawing of the activation pattern in acute Vestibular midbrain infarction.
2016Co-Authors: Sandra Becker-bense, Thomas Brandt, Peter Bartenstein, Hans-georg Buchholz, Bernhard Baier, Mathias Schreckenberger, Andreas Zwergal, Marianne DieterichAbstract:RCGM increases (red) were seen in the contralateral (right) medullary brainstem including the VN and in the cerebellar hemispheres bilaterally. Additional increases in the cerebellar vermis cannot be found on this slice. RCGM decreases (blue) were seen in both entire thalami and areas of the frontal eye fields (FEF). The parieto-insular Vestibular Cortex (PIVC) showed no metabolic changes. Increases within the visual Cortex are not depicted in this drawing. After recovery the infratentorial increases in the brainstem and cerebellum were largely restituted, whereas the supratentorial decreases persisted.
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why acute unilateral Vestibular Cortex lesions mostly manifest without vertigo
Neurology, 2015Co-Authors: Marianne Dieterich, Thomas BrandtAbstract:Objectives: The aim of the current study was, first, to determine the critical causative Vestibular areas that in exceptional cases manifest with transient vertigo or dizziness in acute strokes of the middle cerebral artery, and second, to try to explain why in most cases unilateral lesions of these areas manifest without vertigo. Methods: We determined the ischemic areas of the 10 published cases by overlapping the CT/MRI lesions and attributed them to the temporoparietal Vestibular network. Results: These overlap areas were located either in the posterior retroinsular Cortex (n = 8), i.e., the parieto-insular Vestibular Cortex, or the separate parietal Vestibular Cortex (n = 2). Conclusion: Thus, rare Vestibular cortical vertigo is mostly elicited by acute lesions of the core region of the retroinsular Vestibular network. However, the more interesting question is related to the lack of cortical vertigo when this area is affected. We propose a concept to explain how the unaffected opposite hemisphere can suppress vertigo. This is based on visual–Vestibular interaction for motion perception and orientation. It is the hemisphere in which Vestibular and visual inputs are in agreement, which is the more reliable and determines the global perception of body orientation and motion.
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Central Vestibular Forms of Vertigo
Vertigo and Dizziness, 2013Co-Authors: Thomas Brandt, Marianne Dieterich, Michael StruppAbstract:Neurological disorders of central Vestibular pathways extending from the Vestibular nuclei in the medulla oblongata to the ocular motor nuclei and integration centers in the rostral midbrain and to the Vestibular cerebellum, the thalamus, and multisensory temporoparietal Vestibular Cortex areas are described. They include not only focal lesions due to lacunar infarctions or MS plaques but also degenerative disorders, especially of the cerebellum.
Olaf Blanke - One of the best experts on this subject based on the ideXlab platform.
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Nobel Prize centenary: Robert Barany and the Vestibular system
Current Biology - CB, 2014Co-Authors: Christophe Lopez, Olaf BlankeAbstract:The hundredth anniversary of Robert Barany's Nobel Prize in Medicine offers the opportunity to highlight the importance of his discoveries on the physiology and pathophysiology of the Vestibular organs. Barany developed the method of caloric Vestibular stimulation that revolutionized the investigation of the semicircular canals and that is still widely used today. Caloric Vestibular stimulation launched experimental Vestibular research that was relevant to comprehend the evolution of human locomotion, and Barany's tests continue to be used in neuroscience to understand the influence of Vestibular signals on bodily perceptions, cognition and emotions. Only during the last 20 years has caloric Vestibular stimulation been merged with brain imaging to localize the human Vestibular Cortex.
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The Vestibular system: a spatial reference for bodily self-consciousness
Frontiers in integrative neuroscience, 2014Co-Authors: Christian Pfeiffer, Andrea Serino, Olaf BlankeAbstract:Self-consciousness is the remarkable human experience of being a subject: the ‘I’. Self-consciousness is typically bound to a body, and particularly to the spatial dimensions of the body, as well as to its location and displacement in the gravitational field. Because the Vestibular system codes head position in three-dimensional space, Vestibular Cortex is likely to contribute to spatial aspects of bodily self-consciousness. We review here recent data showing Vestibular effects on first-person perspective (the feeling from where ‘I’ experience the world) and self-location (the feeling where ‘I’ am located in space). We compare these findings to data showing Vestibular effects on mental spatial transformation, self-motion perception, and body representation that show that Vestibular signals contribute to various spatial representations of the body with respect to the external world. Finally, we discuss four posterior brain regions that process Vestibular and other multisensory signals to encode spatial aspects of bodily self-consciousness: temporoparietal junction (TPJ), parietoinsular Vestibular Cortex (PIVC), medial superior temporal region (MST), and ventral intraparietal region (VIP). We propose that Vestibular processing in these cortical regions is important for linking multisensory signals from within personal space with those from extrapersonal space, and for spatial aspects of bodily self-consciousness.
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the human Vestibular Cortex revealed by coordinate based activation likelihood estimation meta analysis
Neuroscience, 2012Co-Authors: Christophe Lopez, Olaf Blanke, F. W. MastAbstract:The Vestibular system contributes to the control of posture and eye movements and is also involved in various cognitive functions including spatial navigation and memory. These functions are subtended by projections to a Vestibular Cortex, whose exact location in the human brain is still a matter of debate (Lopez and Blanke, 2011). The Vestibular Cortex can be defined as the network of all cortical areas receiving inputs from the Vestibular system, including areas where Vestibular signals influence the processing of other sensory (e.g. somatosensory and visual) and motor signals. Previous neuroimaging studies used caloric Vestibular stimulation (CVS), galvanic Vestibular stimulation (GVS), and auditory stimulation (clicks and short-tone bursts) to activate the Vestibular receptors and localize the Vestibular Cortex. However, these three methods differ regarding the receptors stimulated (otoliths, semicircular canals) and the concurrent activation of the tactile, thermal, nociceptive and auditory systems. To evaluate the convergence between these methods and provide a statistical analysis of the localization of the human Vestibular Cortex, we performed an activation likelihood estimation (ALE) meta-analysis of neuroimaging studies using CVS, GVS, and auditory stimuli. We analyzed a total of 352 activation foci reported in 16 studies carried out in a total of 192 healthy participants. The results reveal that the main regions activated by CVS, GVS, or auditory stimuli were located in the Sylvian fissure, insula, retroinsular Cortex, fronto-parietal operculum, superior temporal gyrus, and cingulate Cortex. Conjunction analysis indicated that regions showing convergence between two stimulation methods were located in the median (short gyrus III) and posterior (long gyrus IV) insula, parietal operculum and retroinsular Cortex (Ri). The only area of convergence between all three methods of stimulation was located in Ri. The data indicate that Ri, parietal operculum and posterior insula are Vestibular regions where afferents converge from otoliths and semicircular canals, and may thus be involved in the processing of signals informing about body rotations, translations and tilts. Results from the meta-analysis are in agreement with electrophysiological recordings in monkeys showing main Vestibular projections in the transitional zone between Ri, the insular granular field (Ig), and SII.
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the thalamocortical Vestibular system in animals and humans
Brain Research Reviews, 2011Co-Authors: Christophe Lopez, Olaf BlankeAbstract:The Vestibular system provides the brain with sensory signals about three-dimensional head rotations and translations. These signals are important for postural and oculomotor control, as well as for spatial and bodily perception and cognition, and they are subtended by pathways running from the Vestibular nuclei to the thalamus, cerebellum and the "Vestibular Cortex." The present review summarizes current knowledge on the anatomy of the thalamocortical Vestibular system and discusses data from electrophysiology and neuroanatomy in animals by comparing them with data from neuroimagery and neurology in humans. Multiple thalamic nuclei are involved in Vestibular processing, including the ventroposterior complex, the ventroanterior-ventrolateral complex, the intralaminar nuclei and the posterior nuclear group (medial and lateral geniculate nuclei, pulvinar). These nuclei contain multisensory neurons that process and relay Vestibular, proprioceptive and visual signals to the Vestibular Cortex. In non-human primates, the parieto-insular Vestibular Cortex (PIVC) has been proposed as the core Vestibular region. Yet, Vestibular responses have also been recorded in the somatosensory Cortex (area 2v, 3av), intraparietal sulcus, posterior parietal Cortex (area 7), area MST, frontal Cortex, cingulum and hippocampus. We analyze the location of the corresponding regions in humans, and especially the human PIVC, by reviewing neuroimaging and clinical work. The widespread Vestibular projections to the multimodal human PIVC, somatosensory Cortex, area MST, intraparietal sulcus and hippocampus explain the large influence of Vestibular signals on self-motion perception, spatial navigation, internal models of gravity, one's body perception and bodily self-consciousness.
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The thalamocortical Vestibular system in animals and humans
Brain Research Reviews, 2011Co-Authors: Christophe Lopez, Olaf BlankeAbstract:The Vestibular system provides the brain with sensory signals about three-dimensional head rotations and translations. These signals are important for postural and oculomotor control, as well as for spatial and bodily perception and cognition, and they are subtended by pathways running from the Vestibular nuclei to the thalamus, cerebellum and the ``Vestibular Cortex.'' The present review summarizes current knowledge on the anatomy of the thalamocortical Vestibular system and discusses data from electrophysiology and neuroanatomy in animals by comparing them with data from neuroimagery and neurology in humans. Multiple thalamic nuclei are involved in Vestibular processing, including the ventroposterior complex, the ventroanterior ventrolateral complex, the intralaminar nuclei and the posterior nuclear group (medial and lateral geniculate nuclei, pulvinar). These nuclei contain multisensory neurons that process and relay Vestibular, proprioceptive and visual signals to the Vestibular Cortex. In non-human primates, the parieto-insular Vestibular Cortex (PIVC) has been proposed as the core Vestibular region. Yet, Vestibular responses have also been recorded in the somatosensory Cortex (area 2v, 3av), intraparietal sulcus, posterior parietal Cortex (area 7), area MST, frontal Cortex, cingulum and hippocampus. We analyze the location of the corresponding regions in humans, and especially the human PIVC, by reviewing neuroimaging and clinical work. The widespread Vestibular projections to the multimodal human PIVC, somatosensory Cortex, area MST, intraparietal sulcus and hippocampus explain the large influence of Vestibular signals on self-motion perception, spatial navigation, internal models of gravity, one's body perception and bodily self-consciousness. (C) 2011 Elsevier B.V. All rights reserved.
O J Grusser - One of the best experts on this subject based on the ideXlab platform.
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is there a Vestibular Cortex
Trends in Neurosciences, 1998Co-Authors: W O Guldin, O J GrusserAbstract:Abstract Very different areas of the primate Cortex have been labelled as `Vestibular'. However, no clear concept has emerged as to where and how the Vestibular information is processed in the cerebral Cortex. On the basis of data from single-unit recordings and tracer studies, the present article gives statistical evidence of the existence of a well-defined Vestibular cortical system. Because the data presented here have been verified in three different primate species, it can be predicted that a similar Vestibular cortical system also exists in humans.
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cortico cortical connections and cytoarchitectonics of the primate Vestibular Cortex a study in squirrel monkeys saimiri sciureus
The Journal of Comparative Neurology, 1992Co-Authors: Wolfgang O Guldin, Schahram Akbarian, O J GrusserAbstract:The cortical connections of two Vestibular fields [parieto-insular Vestibular Cortex (PIVC) and area 3aV] were studied in the squirrel monkey (Saimiri sciureus) by means of retrograde tracer techniques. Small iontophoretic or pressure injections of horseradish peroxidase (HRP), wheat-germ-HRP, Nuclear Yellow, and Fast Blue were administered to the cytoarchitectonic areas Ri (PIVC), 3aV, the parieto-temporal association area T3, the granular insula (Ig), and the rostral part of area 7 (7ant). The injection sites were physiologically characterized by means of microelectrode recordings and Vestibular, optokinetic, or somatosensory stimulation: Area Ri is the region of the parieto-insular Vestibular Cortex (PIVC) as defined in macaques. The neck-trunk region of area 3a (area 3aV) also contains many neurons responding to stimulation of semicircular canal receptors. Some neurons of area T3 bordering on the PIVC also receive Vestibular signals, but most neurons in area T3 responded preferentially to large-field optokinetic stimulation and not to Vestibular stimulation. In none of the areas mentioned were responses to otolith stimulation found. The PIVC receives inputs from frontal and parietal cortical areas, especially areas 8a, 6, 3a, 3aV, 2, and 7ant. Area T3 receives signals from the insular and retroinsular Cortex, various parts of area 7, visual areas of the parieto-occipital and parieto-temporal regions (area 19) and from a sector of the upper bank of the temporal sulcus (STS-area). The cortical afferents to area 3aV stem from areas 24, 4, 6, 7ant, from other parts of the primary somatosensory Cortex, the secondary somatosensory Cortex (SII), the retroinsular Cortex (Ri), and the granular insula (Ig). In the border region of the areas 2 and 7ant, labelled neurons appeared after injections into both the PIVC and the area 3aV. This region is presumably the homologue to the Vestibular area 2v of the macaque brain. In all regions cells within the contralateral Cortex were less frequently labelled than cells in the homologous structures of the ipsilateral hemisphere. The cortical system for processing Vestibular information about head-in-space movement consists mainly of the reciprocally interconnected areas PIVC and 3aV, and most likely of border regions of area 2 and 7ant. This "inner cortical Vestibular circuit" also receives signals from two other cortical sensory systems, the somatosensory-proprioceptive system mediated by the primary somatosensory Cortex and the visual movement system (optokinetic or visual flow signals). These visual movement signals reach PIVC via area 19 and area T3.(ABSTRACT TRUNCATED AT 400 WORDS)
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cortico cortical connections and cytoarchitectonics of the primate Vestibular Cortex a study in squirrel monkeys saimiri sciureus
The Journal of Comparative Neurology, 1992Co-Authors: Wolfgang O Guldin, Schahram Akbarian, O J GrusserAbstract:The cortical connections of two Vestibular fields [parieto-insular Vestibular Cortex (PIVC) and area 3aV] were studied in the squirrel monkey (Saimiri sciureus) by means of retrograde tracer techniques. Small iontophoretic or pressure injections of horseradish peroxidase (HRP), wheat-germ-HRP, Nuclear Yellow, and Fast Blue were administered to the cytoarchitectonic areas Ri (PIVC), 3aV, the parieto-temporal association area T3, the granular insula (Ig), and the rostral part of area 7 (7ant). The injection sites were physiologically characterized by means of microelectrode recordings and Vestibular, optokinetic, or somatosensory stimulation: Area Ri is the region of the parieto-insular Vestibular Cortex (PIVC) as defined in macaques. The neck-trunk region of area 3a (area 3aV) also contains many neurons responding to stimulation of semicircular canal receptors. Some neurons of area T3 bordering on the PIVC also receive Vestibular signals, but most neurons in area T3 responded preferentially to large-field optokinetic stimulation and not to Vestibular stimulation. In none of the areas mentioned wereresponses to otolith stimulation found. The PIVC receives inputs from frontal and parietal cortical areas, especially areas 8a, 6, 3a, 3aV, 2, and 7ant. Area T3 receives signals from theinsular and retroinsular Cortex, various parts of area 7, visual areas of the parieto-occipital and parieto-temporal regions (area 19) and from a sector of the upper bank of the temporal sulcus (STS-area). The cortical afferents to area 3aV stem from areas 24, 4, 6, 7ant, from other parts of the primary somatosensory Cortex, the secondary somatosensory Cortex (SII), the retroinsular Cortex (Ri), and the granular insula (Ig). In the border region of the areas 2 and 7ant, labelled neurons appeared after injections into both the PIVC and the area 3aV. This region is presumably the homologue to the Vestibular area 2v of the macaque brain. In all regions cells within the contralateral Cortex were less frequently labelled than cells in the homologous structures of the ipsilateral hemisphere. The cortical system for processing Vestibular information about head-in-space movement consists mainly of the reciprocally interconnected areas PIVC and 3aV, and most likely of border regions of area 2 and 7ant. This “inner cortical Vestibular circuit” also receives signals from two other cortical sensory systems, the somatosensory-proprioceptive system mediated by the primary somatosensory Cortex and the visual movement system (optokinetic or visual flow signals). These visual movement signals reach PIVC via area 19 and area T3. The cortical somatosensory and visual inputs mayupdate the multimodal (proprioceptive, visual, and Vestibular) signal integration already occuring in the afferent Vestibular system at the level of brainstem Vestibular nuclei. Furthermore, the PIVC, area 3aV, and area T3 are connected to the same parts of area 6, the granular insula, area 7ant, and the anterior cingulate region. Therefore, circumscribed parts of the premotor, cingulate, insular, and parietal association Cortex participate in the cortical network monitoring head and body movements in space. © 1992 Wiley-Liss, Inc.
Thomas Stephan - One of the best experts on this subject based on the ideXlab platform.
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the human Vestibular Cortex
ScienceOpen Posters, 2020Co-Authors: Peter Zu Eulenburg, Marianne Dieterich, Thomas Stephan, Ria Maxine RuehlAbstract:Aim: The cortical representations for almost all senses (touch, pain, sound, vision and smell) haven been robustly mapped in humans with functional neuroimaging. But the majority of cerebral regions receiving Vestibular information originating from our so-called sixth sense have evaded a definitive localization for more than two decades now. Neuron recordings and tracer studies in several primate species had previously established a cortical Vestibular network of at least seven (maximum ten) regions per hemisphere [ 1 , 2 ]. Up to now, several confounders impeded the delineation of a human Vestibular Cortex. These included somatosensory confounders, head motion artifacts, difficulties in evoking an intense Vestibular percept and spatio-temporal limitations of fMRI. Aim of our fMRI study was to finally localize all cortical Vestibular regions known from other primate species in humans. In a subsequent step we also intended to perform an internal replication of our findings. Methods: We examined 60 stimulus-naive, right-handed healthy subjects (33 F; mean age 27 years) in two separate groups (n=30) spanning a cultural background of 17 different nationalities. Sinusoidal low-frequency galvanic Vestibular stimulation (GVS) (0.875Hz, 3mA) after local anaesthesia of the postauricular region was conducted via bimastoidal electrodes to elicit naturalistic Vestibular sensations. Structural and functional images were obtained in a clinical 3T scanner (Siemens Magnetom Skyra) equipped with a 64-channel head and neck coil. The protocol included a resting-state and a GVS session consisting of a prescan-normalized T2*-weighted EPI sequence (TR 0.7s, 56 interleaved slices, multi-band factor 6, 2.5mm in-plane resolution, slice thickness 2.5 mm), as well as a structural MPRAGE sequence. Data analysis was performed using SPM12 (Version 6407 Wellcome Department of Imaging Neuroscience, UK) and the SPM Anatomy toolbox (Version 2.2c) after standard preprocessing including DARTEL-based normalization[ 3 ]. Results were considered significant at FDR p<0.01 (corrected at voxel level). Results: Controlling and accounting for somatosensory, nociceptive and salience effects we were able to delineate and identify nine cortical homologues to known Vestibular representations in non-human primates. Aside from the cerebellar nodule and uvula we found the cytoarchitectonic area OP2 in the parietal operculum to be the human core equivalent to the parieto-insular Vestibular region PIVC. Monkey visual posterior sylvian area (VPS) could be mapped to cytoarchitectonic area PFcm whereas area 7 is probably located in the human inferior parietal lobule (cytoarchitectonic area PF). We could also identify the ventral intraparietal area (VIP) in the intraparietal sulcus (cytoarchitectonic area hIP3) as well as areas 2v and 3aV. The area cingulate sulcus visual (CSv) was found to be the Vestibular cingulate (VC) region known from non-human primates. We found a strong Vestibular response in already established area MST und could map monkey area 6 to a lateral premotor region in humans. The Vestibular reponse found in the periarcuate Cortex in monkeys is probably reflected in a paramedian human activation in the supplementary motor area. All of these findings could be replicated internally in the second independent cohort. Conclusion: We were able to robustly delineate and map the human Vestibular Cortex. We identified ten cortical homologue Vestibular regions known from non-human primates. The response patterns to the confounder-minimised GVS protocol show that the cortical core Vestibular network in humans is probably represented by areas OP2 (PIVC), MST, PFcm (VPS), PF (area 7) and CSv (VC). References: This work was supported by the Federal Ministry of Education and Research (BMBF 01 EO 0901).
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The human Vestibular Cortex
2020Co-Authors: Peter Zu Eulenburg, Marianne Dieterich, Thomas Stephan, Ria Maxine RuehlAbstract:Aim: The cortical representations for almost all senses (touch, pain, sound, vision and smell) haven been robustly mapped in humans with functional neuroimaging. But the majority of cerebral regions receiving Vestibular information originating from our so-called sixth sense have evaded a definitive localization for more than two decades now. Neuron recordings and tracer studies in several primate species had previously established a cortical Vestibular network of at least seven (maximum ten) regions per hemisphere [ 1 , 2 ]. Up to now, several confounders impeded the delineation of a human Vestibular Cortex. These included somatosensory confounders, head motion artifacts, difficulties in evoking an intense Vestibular percept and spatio-temporal limitations of fMRI. Aim of our fMRI study was to finally localize all cortical Vestibular regions known from other primate species in humans. In a subsequent step we also intended to perform an internal replication of our findings. Methods: We examined 60 stimulus-naive, right-handed healthy subjects (33 F; mean age 27 years) in two separate groups (n=30) spanning a cultural background of 17 different nationalities. Sinusoidal low-frequency galvanic Vestibular stimulation (GVS) (0.875Hz, 3mA) after local anaesthesia of the postauricular region was conducted via bimastoidal electrodes to elicit naturalistic Vestibular sensations. Structural and functional images were obtained in a clinical 3T scanner (Siemens Magnetom Skyra) equipped with a 64-channel head and neck coil. The protocol included a resting-state and a GVS session consisting of a prescan-normalized T2*-weighted EPI sequence (TR 0.7s, 56 interleaved slices, multi-band factor 6, 2.5mm in-plane resolution, slice thickness 2.5 mm), as well as a structural MPRAGE sequence. Data analysis was performed using SPM12 (Version 6407 Wellcome Department of Imaging Neuroscience, UK) and the SPM Anatomy toolbox (Version 2.2c) after standard preprocessing including DARTEL-based normalization[ 3 ]. Results were considered significant at FDR p
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structural and functional plasticity of the hippocampal formation in professional dancers and slackliners
Hippocampus, 2010Co-Authors: Katharina Hüfner, Thomas Stephan, Stefan Glasauer, Carolina Binetti, Derek A Hamilton, Virginia L Flanagin, Jennifer Linn, Kirsten Labudda, Hans J Markowitsch, Klaus JahnAbstract:The acquisition of special skills can induce plastic changes in the human hippocampus, a finding demonstrated in expert navigators (Maguire et al. (2000) Proc Natl Acad Sci USA 97:4,398-403). Conversely, patients with acquired chronic bilateral Vestibular loss develop atrophy of the hippocampus, which is associated with impaired spatial memory (Brandt et al. (2005) Brain 128:2,732-741). This suggests that spatial memory relies on Vestibular input. In this study 21 professional dancers and slackliners were examined to assess whether balance training with extensive vestibulo-visual stimulation is associated with altered hippocampal formation volumes or spatial memory. Gray matter voxel-based morphometry showed smaller volumes in the anterior hippocampal formation and in parts of the parieto-insular Vestibular Cortex of the trained subjects but larger volumes in the posterior hippocampal formation and the lingual and fusiform gyri bilaterally. The local volumes in the right anterior hippocampal formation correlated negatively and those in the right posterior hippocampal formation positively with the amount of time spent training ballet/ice dancing or slacklining at the time of the study. There were no differences in general memory or in spatial memory as assessed by the virtual Morris water task. Trained subjects performed significantly better on a hippocampal formation-dependent task of nonspatial memory (transverse patterning). The smaller anterior hippocampal formation volumes of the trained subjects may be the result of a long-term suppression of destabilizing Vestibular input. This is supported by the associated volume loss in the parieto-insular Vestibular Cortex. The larger volumes in the posterior hippocampal formation of the trained subjects might result from their increased utilization of visual cues for balance. This is supported by the concomitant larger volumes in visual areas like the lingual and fusiform gyri. Our findings indicate that there is a spatial separation of Vestibular and visual processes in the human hippocampus.
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Vestibular Cortex activation during locomotor imagery in the blind.
Annals of the New York Academy of Sciences, 2009Co-Authors: Angela Deutschländer, Thomas Brandt, Thomas Stephan, Katharina Hüfner, Judith Wagner, Martin Wiesmann, Michael Strupp, Klaus JahnAbstract:A previous functional magnetic resonance imaging (fMRI) study in sighted individuals showed deactivations of multisensory Vestibular Cortex areas in the posterior insula and adjacent temporal sites during locomotor imagery. These Vestibular deactivations were suggested to reflect the suppression of Vestibular signals during locomotion in order to prevent potentially adverse interactions of these inputs with the optimized automated locomotion pattern. In this fMRI experiment, 10 totally blind subjects and 10 age- and gender-matched sighted controls imagined several locomotor tasks in a first-person perspective (kinesthetic imagery of standing, walking, and running). As opposed to their sighted controls, totally blind individuals activated multisensory Vestibular areas in the posterior insula and superior temporal gyrus, with right-sided preponderance during locomotor imagery. These results plausibly suggest that blind subjects rely more on Vestibular feedback for locomotor control than do sighted subjects. Thus, this fMRI study provides neuroimaging evidence for distinct cortical processing in the multisensory Vestibular system in the blind during locomotor control.
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medial Vestibular nucleus lesions in wallenberg s syndrome cause decreased activity of the contralateral Vestibular Cortex
Annals of the New York Academy of Sciences, 2005Co-Authors: Marianne Dieterich, Thomas Brandt, S Bense, Thomas Stephan, Markus Schwaiger, P BartensteinAbstract:Three patients with the clinical diagnosis of Wallenberg's syndrome caused by acute unilateral ischemic infarctions, which included the Vestibular nucleus in the medullary brain stem and afferent Vestibular pathways, were examined by positron emission tomography (PET) during caloric Vestibular stimulation. They all had typical signs of Vestibular dysfunction such as transient rotatory vertigo with vomiting at the onset, ipsiversive body and ocular lateropulsion, and a complete ocular tilt reaction with tilts of the subjective visual vertical. Compared with healthy volunteers, who show activation in a network of temporoparietal Vestibular areas within both hemispheres, especially in the posterior insula and retroinsular region that contains the human homologue of the parietoinsular Vestibular Cortex (PIVC) in monkeys, the activation pattern of the patients with Wallenberg's syndrome was typically changed. During caloric irrigation of the ear ipsilateral to the side of the lesion, they showed no or significantly reduced activation in the contralateral hemisphere, whereas the activation pattern in the ipsilateral hemisphere appeared "normal." These results are compatible with bilateral ascending Vestibular pathways from the Vestibular nuclei to the Vestibular Cortex. The novel finding in all three patients was that the activation patterns were compatible with the assumption that only the crossing fibers from the medial Vestibular subnucleus to the contralateral medial longitudinal fascicle were affected, but the ipsilateral Vestibular thalamocortical projections via the superior Vestibular subnucleus were spared. Thus, the activation pattern in the PET study may reflect the Vestibular tonic imbalance within the Vestibular nuclei circuitry at the cortical level.