II. Anatomy: Superior (Rostral) Medulla Components

  1. Fourth Ventricle
  2. Nucleii (organized in anterior-to-posterior bands)
    1. Somatic Motor Nucleii (most medial)
      1. CN 12: Hypoglossal Nerve (motor, Tongue)
    2. Somatovisceral nerves (Branchiomeric Nerves)
      1. Nucleus Ambiguous (CN 9, CN 10, swallow)
    3. Visceral Motor Nucleii
      1. CN 9: Glossopharyngeal Nerve (Inferior Salivatory nucleus)
      2. CN 10: Vagus Nerve (Dorsal motor nucleus )
    4. Visceral Sensory Nucleii
      1. Nucleus Solitarius (CN 7, CN 9, CN 10)
    5. Somatic Sensory Nucleii (most lateral)
      1. CN 8: Acoustic Nerve
      2. Sensory Nucleus 5 (CN 5, CN 7, CN 9, CN 10)
  3. Spinothalamic Tract
    1. Continued pain and Temperature sensation tracts from the spinal cord
  4. Spinocerebellar Tract
    1. Continued tracts for transmitting UNCONSCIOUS proprioception sensation (e.g. walking)
    2. Remains ipsilateral as it courses to the Cerebellum via the superior and inferior peduncles
  5. Medial Lemniscus
    1. Proprioception sensation from Posterior Columns (via Internal Arcuate Tract)
    2. Within the tract, head is represented posteriorly and legs anteriorly (as if standing on the pyramids)
  6. Inferior Olivary Nucleus (inferior olive)
    1. Coordination of specialized task related movement (via Cerebellum)
  7. Anterior pyramids
    1. Corticospinal tract
      1. Continued motor tracts to the spinal cord

III. Anatomy: Inferior (Caudal) Medulla Components

  1. Nucleii for Posterior Columns or dorsal columns (sensory, posterior cord)
    1. Transmits CONSCIOUS proprioception, vibratory sensation and stereognosis (and partially light touch)
      1. Sensory signals rise within the spinal cord from Fasciculus Gracilis and Fasciculus Cuneatus
      2. Synapse at the Nucleus Gracilis and Nucleus Cuneatus in Medulla to form Internal Arcuate Tract
      3. Internal Arcuate Tract crosses over the midline at the Medulla to form Medial Lemniscus
      4. Medial Lemniscus courses to contralateral Thalamus and cerebral cortex
    2. Nucleus Gracilis
      1. Transmits proprioception sensory signals from the lower part of the body
    3. Nucleus Cuneatus
      1. Transmits proprioception sensory signals from the upper part of the body
  2. Somatic Sensory Nucleii (most lateral)
    1. Sensory Nucleus 5 (CN 5, CN 7, CN 9, CN 10)
  3. Spinothalamic Tract
    1. Continued pain and Temperature sensation tracts from the spinal cord
  4. Spinocerebellar Tract
    1. Continued tracts for transmitting UNCONSCIOUS proprioception sensation (e.g. walking)
    2. Remains ipsilateral as it courses to the Cerebellum via the superior and inferior peduncles
  5. Crossings (Decussations)
    1. Medial Lemniscus (from Posterior Columns via Internal Arcuate Tract) Decussation
    2. Corticospinal tract Decussation

IV. Anatomy: Vascular

  1. Anterior Spinal Artery
    1. Supplies midline Medulla
  2. Vertebral Artery
    1. Supplies Medulla between Anterior Spinal Artery and PICA
  3. Posterior Inferior Cerebellar Artery (PICA)
    1. Supplies posterolateral Medulla

V. Anatomy: Images

  1. Rostral (superior cross-section)
    1. medullaRostral.png
  2. Caudal (inferior cross-section)
    1. medullaCaudal.png
  3. Other images
    1. neuroMedullaXsAtOliveGrayBB694.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    2. neuroMedullaXsAtOliveGrayBB695.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)

VI. References

  1. Gilman (1989) Manter and Gatz Essentials of Neuroanatomy and Neurophysiology, Davis, p. 81-96
  2. Goldberg (2014) Clinical Neuroanatomy, Medmaster, p. 24-39
  3. Netter (1997) Atlas Human Anatomy, ICON Learning, p. 108-12

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Ontology: Medulla Oblongata (C0025148)

Definition (FMA) Organ component of neuraxis that has as its parts the medullary reticular formation, inferior olivary complex and cochlear nuclear complex, among other structures. Examples: There is only one medulla oblongata.
Definition (CHV) part of brain
Definition (CHV) part of brain
Definition (NCI_CDISC) The lower portion of the brainstem located between the pons and brainstem. This structure contains several descending and ascending tracts, lower cranial nerve nuclei, a significant proportion of the reticular system of the brainstem and other structures. (NCI)
Definition (NCI) The lower portion of the brainstem located between the pons and brainstem. This structure contains several descending and ascending tracts, lower cranial nerve nuclei, a significant proportion of the reticular system of the brainstem and other structures.
Definition (CSP) caudal subdivision of the hindbrain interposed between the spinal cord and the pons; adult derivative of the myelencephalon, the most caudal subdivision of the developing brain; it has two subdivisions the open medulla bordering on the fourth ventricle and the closed medulla which surrounds the rostral part of the central canal.
Definition (MSH) The lower portion of the BRAIN STEM. It is inferior to the PONS and anterior to the CEREBELLUM. Medulla oblongata serves as a relay station between the brain and the spinal cord, and contains centers for regulating respiratory, vasomotor, cardiac, and reflex activities.
Concepts Body Part, Organ, or Organ Component (T023)
MSH D008526
SnomedCT 26519002
English Medulla Oblongata, Medulla Oblongatas, Medulla, Medullary, Metepencephalon, Bulb, bulbus, metepencephalon, medulla oblongata, MO, medulla, Myelencephalon, Bulbus, BRAIN, MEDULLA OBLONGATA, MEDULLA OBLONGATA, Medulla oblongata, Medulla oblongata structure, Medulla oblongata structure (body structure), Medulla oblongata, NOS
French Medulla oblongata, Bulbe rachidien, Bulbe, Moelle allongée
Swedish Förlängda märgen
Czech medulla oblongata, prodloužená mícha
Spanish Bulbo Raquídeo, Médula Oblongada, bulbo raquídeo, estructura del bulbo raquídeo (estructura corporal), estructura del bulbo raquídeo
Finnish Ydinjatke
Russian MOZG PRODOLGOVATYI, МОЗГ ПРОДОЛГОВАТЫЙ
Latvian Iegarenās smadzenes, Smadzenes, iegarenās
Polish Rdzeń przedłużony
Norwegian Den forlengede marg, Medulla oblongata, forlengede marg
Portuguese Bulbo Raquiano, Medula Oblonga, Bulbo
German Medulla oblongata
Italian Midollo allungato
Dutch Medulla oblongata, Myelencephalon, Verlengde merg

Ontology: Inferior olivary nucleus (C0228540)

Concepts Body Part, Organ, or Organ Component (T023)
SnomedCT 26193009
English Inferior olivary nucleus, Complexus olivaris inferior, Inferior olivary complex, Inferior olive, Oliva, Inferior olivary nuclear complex, inferior olivary nuclear complex, inferior olivary complex, inferior olive, inferior olivary complex (Vieussens), IO, inferior olivary nucleus, Nuclei olivares inferiores, Regio olivaris inferior, Nucleus olivaris inferior, Nucleus olivaris caudalis, Structure of inferior olivary nucleus (body structure), Structure of inferior olivary nucleus
Spanish estructura del núcleo olivar inferior (estructura corporal), estructura del núcleo olivar inferior, núcleo olivar inferior