Medial Vestibulospinal Tract

The medial vestibulospinal tract is one of the descending spinal tracts of the ventromedial pathway.

The medial part of the vestibulospinal tract is the smaller part, and is primarily made of fibers from the medial vestibular nucleus. It projects bilaterally down the spinal cord and triggers the ventral horn of the cervical spinal circuits, particularly controlling lower motor neurons associated with the spinal accessory nerve (CN XI). Additionally, the pathway projects superiorly to the paramedian pontine reticular formation, indirectly innervating the nuclei of CN VI and III. Through this superior projection, the medial vestibulospinal tract is involved in "yoking" the eyes together in response to rapid movement of the head. Thus, cumulatively it controls position of the head, neck, and eyes in response to changes in posture.

Anatomy of torso (primarily): the spinal cord (TA 14.1.02, GA 9.749)
External, dorsal Posterior median sulcus · Posterolateral sulcus
Grey matter/
Rexed laminae
I–VI: Posterior horn I: Marginal nucleus · II: Substantia gelatinosa of Rolando · III+IV: Nucleus proprius · Spinal lamina V · Spinal lamina VI
VII: Lateral horn Intermediolateral nucleus · Posterior thoracic nucleus
VIII–IX: Anterior horn Interneuron · Alpha motor neuron (Onuf's nucleus)
X: Other Central gelatinous substance · Gray commissure
Central canal · Terminal ventricle
White matter
somatic/
ascending
(blue)

Posterior/PCML: touch: Gracile · Cuneate

Lateral: proprioception: Spinocerebellar (Dorsal, Ventral) · pain/temp: Spinothalamic (Lateral, Anterior) · Posterolateral (Lissauer) · Spinotectal

Spinoreticular tract · Spino-olivary tract
motor/
descending
(red)
Lateral: Corticospinal (Lateral) · Ep (Rubrospinal, Olivospinal)
Anterior: Corticospinal (Anterior) · Ep (Vestibulospinal, Reticulospinal, Tectospinal)
both Anterior white commissure
External, ventral Anterior median fissure · Anterolateral sulcus
External, general Cervical enlargement · Lumbar enlargement · Conus medullaris · Filum terminale · Cauda equina

M: CNS

anat (n/s/m/p/4/e/b/d/c/a/f/l/g)/phys/devp

noco (m/d/e/h/v/s)/cong/tumr, sysi/epon, injr

proc, drug (N1A/2AB/C/3/4/7A/B/C/D)

Human brain, rhombencephalon, metencephalon: pons (TA A14.1.05.101–604, GA 9.785)
Dorsal/
(tegmentum)
Surface Cerebellopontine angle · Superior medullary velum · Sulcus limitans · Medial eminence · Facial colliculus
White: Sensory/ascending

Trapezoid body/VIII · Trigeminal lemniscus (Dorsal trigeminal tract, Ventral trigeminal tract) · Medial lemniscus · Lateral lemniscus

MLF, III, IV and VI: Vestibulo-oculomotor fibers

Anterior trigeminothalamic tract · Central tegmental tract
White: Motor/descending

ICP (Vestibulocerebellar tract)

MLF, III, IV and VI: Vestibulospinal tract (Medial vestibulospinal tract, Lateral vestibulospinal tract)
Grey: Cranial nuclei

afferent: GSA: Principal V/Spinal V · VIII-c (Dorsal, Anterior)/VIII-v (Superior)

efferent: SVE: Motor V · VII · GSE: VI · GVE: VII: Superior salivary nucleus
Other grey Apneustic center · Pneumotaxic center (Medial parabrachial nucleus) · Lateral parabrachial nucleus · Superior olivary nucleus · Caerulean nucleus
Ventral/
(base)
Grey Pontine nuclei
White: Motor/descending

Corticospinal tract · Corticobulbar tract · Corticopontine fibers

MCP (Pontocerebellar fibers)
Surface Basilar sulcus
Other grey: Raphe/
reticular
Reticular formation (Caudal, Oral, Tegmental, Paramedian) · Raphe nuclei (Median)

M: CNS

anat (n/s/m/p/4/e/b/d/c/a/f/l/g)/phys/devp

noco (m/d/e/h/v/s)/cong/tumr, sysi/epon, injr

proc, drug (N1A/2AB/C/3/4/7A/B/C/D)

Brain and spinal cord: neural tracts and fasciculi
Sensory/
ascending
PCML

1°: Pacinian corpuscle/Meissner's corpuscle → Posterior column (Gracile fasciculus/Cuneate fasciculus) → Gracile nucleus/Cuneate nucleus

2°: → sensory decussation/arcuate fibers (Posterior external arcuate fibers, Internal arcuate fibers) → Medial lemniscus/Trigeminal lemniscus → Thalamus (VPL, VPM)

3°: → Posterior limb of internal capsule → Postcentral gyrus
Anterolateral/
pain
Fast/lateral

1° (Free nerve ending → A delta fiber) → 2° (Anterior white commissure → Lateral and Anterior Spinothalamic tract → Spinal lemniscus → VPL of Thalamus) → 3° (Postcentral gyrus) → 4° (Posterior parietal cortex)

2° (Spinotectal tract → Superior colliculus of Midbrain tectum)
Slow/medial 1° (Group C nerve fiber → Spinoreticular tract → Reticular formation) → 2° (MD of Thalamus) → 3° (Cingulate cortex)
Motor/
descending
Pyramidal flexion: Primary motor cortex → Posterior limb of internal capsule → Decussation of pyramids → Corticospinal tract (Lateral, Anterior) → Neuromuscular junction
Extrapyramidal

flexion: Primary motor cortex → Genu of internal capsule → Corticobulbar tract → Facial motor nucleus → Facial muscles

flexion: Red nucleus → Rubrospinal tract

extension: Vestibulocerebellum → Vestibular nuclei → Vestibulospinal tract

extension: Vestibulocerebellum → Reticular formation → Reticulospinal tract

Midbrain tectum → Tectospinal tract → muscles of neck
Basal ganglia

direct: 1° (Motor cortex → Striatum) → 2° (GPi) → 3° (Lenticular fasciculus/Ansa lenticularis → Thalamic fasciculus → VL of Thalamus) → 4° (Thalamocortical radiations → Supplementary motor area) → 5° (Motor cortex)

indirect: 1° (Motor cortex → Striatum) → 2° (GPe) → 3° (Subthalamic fasciculus → Subthalamic nucleus) → 4° (Subthalamic fasciculus → GPi) → 5° (Lenticular fasciculus/Ansa lenticularis → Thalamic fasciculus → VL of Thalamus) → 6° (Thalamocortical radiations → Supplementary motor area) → 7° (Motor cortex)

nigrostriatal pathway: Pars compacta → Striatum
Cerebellar
Afferent

Vestibular nucleus → Vestibulocerebellar tract → ICP → Cerebellum → Granule cell

Pontine nuclei → Pontocerebellar fibers → MCP → Deep cerebellar nuclei → Granule cell

Inferior olivary nucleus → Olivocerebellar tract → ICP → Hemisphere → Purkinje cell → Deep cerebellar nuclei
Efferent

Dentate nucleus in Lateral hemisphere/pontocerebellum → SCP → Dentatothalamic tract → Thalamus (VL) → Motor cortex

Interposed nucleus in Intermediate hemisphere/spinocerebellum → SCP → Reticular formation, or → Cerebellothalamic tract → Red nucleus → Thalamus (VL) → Motor cortex

Fastigial nucleus in Flocculonodular lobe/vestibulocerebellum → Vestibulocerebellar tract → Vestibular nucleus
Bidirectional:
Spinocerebellar
Unc. prop.

lower limb → 1° (muscle spindles → DRG) → 2° (Posterior thoracic nucleus → Dorsal/posterior spinocerebellar tract → ICP → Cerebellar vermis)

upper limb → 1° (muscle spindles → DRG) → 2° (Accessory cuneate nucleus → Cuneocerebellar tract → ICP → Anterior lobe of cerebellum)
Reflex arc

lower limb → 1° (Golgi tendon organ) → 2° (Ventral/anterior spinocerebellar tract→ SCP → Cerebellar vermis)

upper limb → 1° (Golgi tendon organ) → 2° (Rostral spinocerebellar tract → ICP → Cerebellum)

M: CNS

anat (n/s/m/p/4/e/b/d/c/a/f/l/g)/phys/devp

noco (m/d/e/h/v/s)/cong/tumr, sysi/epon, injr

proc, drug (N1A/2AB/C/3/4/7A/B/C/D)

M: PNS

anat (h/r/t/c/b/l/s/a)/phys (r)/devp/prot/nttr/nttm/ntrp

noco/auto/cong/tumr, sysi/epon, injr

proc, drug (N1B)

Auditory and vestibular pathways
Auditory
  • inner ear: Hair cells → Spiral ganglion → Cochlear nerve VIII →
  • pons: Cochlear nuclei (Anterior, Dorsal) → Trapezoid body → Superior olivary nuclei →
  • midbrain: Lateral lemniscus → Inferior colliculi →
  • thalamus: Medial geniculate nuclei →
  • cerebrum: Acoustic radiation → Primary auditory cortex
Vestibular
  • inner ear: Vestibular nerve VIII →
  • pons: Vestibular nuclei (Medial vestibular nucleus, Lateral vestibular nucleus)
  • cerebellum: Flocculonodular lobe
  • spinal cord: Vestibulospinal tract (Medial vestibulospinal tract, Lateral vestibulospinal tract)
  • thalamus: Ventral posterolateral nucleus
  • cerebrum: Vestibular cortex
  • Vestibulo-oculomotor fibers

M: EAR

anat (e/p)/phys/devp

noco/cong, epon

proc, drug (S2)

Other articles related to "medial vestibulospinal tract, medial, medial vestibulospinal":

Anatomy - Medial Vestibulospinal Tract
... The medial vestibulospinal tract is a group of descending extrapyramidal motor neurons, or efferent fibers found in the anterior funiculus, a bundle of nerve roots in the spinal cord ... The medial vestibulospinal tract originates in the medial vestibular nucleus or Schwalbe's nucleus ... Medial vestibulospinal fibers join with the ipsilateral and contralateral medial longitudinal fasciculus, and descend in the anterior funiculus of the spinal cord ...

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