title: Structural and functional connectivity mapping of the vestibular circuitry from human brainstem to cortex.
abstract: Structural and functional interconnections of the bilateral central vestibular network have not yet been completely delineated. This includes both ipsilateral and contralateral pathways and crossing sites on the way from the vestibular nuclei via the thalamic relay stations to multiple "vestibular cortex" areas. This study investigated "vestibular" connectivity in the living human brain in between the vestibular nuclei and the parieto-insular vestibular cortex (PIVC) by combined structural and functional connectivity mapping using diffusion tensor imaging and functional connectivity magnetic resonance imaging in 24 healthy right-handed volunteers. We observed a congruent functional and structural link between the vestibular nuclei and the ipsilateral and contralateral PIVC. Five separate and distinct vestibular pathways were identified: three run ipsilaterally, while the two others cross either in the pons or the midbrain. Two of the ipsilateral projections run through the posterolateral or paramedian thalamic subnuclei, while the third bypasses the thalamus to reach the inferior part of the insular cortex directly. Both contralateral pathways travel through the posterolateral thalamus. At the cortical level, the PIVC regions of both hemispheres with a right hemispherical dominance are interconnected transcallosally through the antero-caudal splenium. The above-described bilateral vestibular circuitry in its entirety takes the form of a structure of a rope ladder extending from the brainstem to the cortex with three crossings in the brainstem (vestibular nuclei, pons, midbrain), none at thalamic level and a fourth cortical crossing through the splenium of the corpus callosum.
authors.affiliation: Department of Neurology, University Hospital, Ludwig-Maximilians University, Marchioninistraße 15, 81377, Munich, Germany. valerie.kirsch@med.lmu.de.|Graduate School of Systemic Neuroscience, Ludwig-Maximilians University, Munich, Germany. valerie.kirsch@med.lmu.de.|German Center for Vertigo and Balance Disorders-IFBLMU, Ludwig-Maximilians University, Munich, Germany. valerie.kirsch@med.lmu.de.
authors.forename: V
authors.initials: V
authors.lastname: Kirsch
authors.affiliation: Department of Radiology, Ludwig-Maximilians University, Munich, Germany.|Department of Psychiatry, Ludwig-Maximilians University, Munich, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Keeser
authors.affiliation: Department of Neurology, University Hospital, Ludwig-Maximilians University, Marchioninistraße 15, 81377, Munich, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Hergenroeder
authors.affiliation: Department of Neurology, University Hospital, Ludwig-Maximilians University, Marchioninistraße 15, 81377, Munich, Germany.
authors.forename: O
authors.initials: O
authors.lastname: Erat
authors.affiliation: German Center for Vertigo and Balance Disorders-IFBLMU, Ludwig-Maximilians University, Munich, Germany.|Department of Radiology, Ludwig-Maximilians University, Munich, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Ertl-Wagner
authors.affiliation: German Center for Vertigo and Balance Disorders-IFBLMU, Ludwig-Maximilians University, Munich, Germany.|Clinical Neuroscience, Ludwig-Maximilians University, 81377, Munich, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Brandt
authors.affiliation: Department of Neurology, University Hospital, Ludwig-Maximilians University, Marchioninistraße 15, 81377, Munich, Germany.|Graduate School of Systemic Neuroscience, Ludwig-Maximilians University, Munich, Germany.|German Center for Vertigo and Balance Disorders-IFBLMU, Ludwig-Maximilians University, Munich, Germany.|Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Dieterich
mesh_terms: D000328:Adult; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000033:anatomy & histology* / Q000502:physiology*; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009434:Neural Pathways / Q000033:anatomy & histology / Q000502:physiology; D010296:Parietal Lobe / Q000033:anatomy & histology* / Q000502:physiology*; D012027:Reflex, Vestibulo-Ocular; D014726:Vestibular Nuclei / Q000033:anatomy & histology* / Q000502:physiology*; D055815:Young Adult
keywords: Structural and functional connectivity mapping; Vestibular cortex; Vestibular pathways; Vestibular system; Vestibular thalamus