II. Anatomy: Components

  1. Midbrain
    1. Most superior aspect of the Brainstem
    2. Lies immediately inferior to the Diencephalon
  2. Pons Cerebri
    1. Lies deep to the Pituitary Gland and Circle of Willis
  3. Medulla Oblongata
    1. Immediately superior to the spinal cord
    2. Lies deep to the clivus (slanted bony surface)
    3. Lies just above the foramen magnum (hole at skull base)
      1. With Cerebral Herniation, the Medulla is the first to drop through the foramen magnum

III. Anatomy: Cross Section

  1. Brain stem Cranial Nerve origins follow a consistent pattern of distribution
  2. Nucleii are located anterior to the ventricles
  3. Nucleii are organized in anterior-to-posterior bands
    1. Somatic Motor Nucleii (most medial)
      1. CN 3: Oculomotor Nerve (eye)
      2. CN 4: Trochlear Nerve (eye)
      3. CN 6: Abducens Nerve (eye)
      4. CN 11: Spinal Accessory nerve (neck/Shoulders)
      5. CN 12: Hypoglossal Nerve (motor, Tongue)
    2. Somatovisceral nerves (Branchiomeric Nerves)
      1. CN 5: Trigeminal Nerve (motor nucleus 5, chew)
      2. CN 7: Facial Nerve (facial nucleus, lips/eyes)
      3. Nucleus Ambiguous (CN 9, CN 10, swallow)
    3. Visceral Motor Nucleii
      1. CN 3: Oculomotor Nerve (Edinger-Westphal Nucleus)
      2. CN 7: Facial Nerve (Superior Salivatory Nucleus)
      3. CN 9: Glossopharyngeal Nerve (Inferior Salivatory nucleus)
      4. 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)
    6. Exceptions
      1. CN 1 and CN 2 are not included as they originate superior to the Brainstem in the diencephalon

IV. Anatomy: Shared Cranial Nerve Nucleii

  1. Nucleus Solitarius
    1. Located in the Medulla, visceral sensory region
    2. Multiple Cranial Nerve functions
      1. Taste Sensation (CN 7, CN 9, CN 10)
      2. Sensory signals from carotid sinus and carotid body (CN 9)
      3. Sensory signals (CN 10)
  2. Nucleus Ambiguous
    1. Located in the Medulla, somatovisceral region
    2. Multiple Cranial Nerve functions
      1. Swallowing (CN 9, CN 10)
      2. Speech via vocal cord innervation (CN 10)

V. Anatomy: Images

  1. High-Level Anatomic Relationships
    1. neuroBrainXsGrayBB715.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    2. neuroBrainXsGrayBB720.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    3. neuroBrainIllustrationXsGrayBB768.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    4. neuroBrainstemGrayBB677.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    5. neuroBrainStemGrayBB678.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
  2. Cranial Nerves Brainstem exits
    1. neuroBrainInferiorGrayBB724.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    2. neuroBrainStemGrayBB681.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
  3. Cranial Nerve Nucleii
    1. neuroBrainstemGrayBB691.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    2. neuroBrainstemFiberCourseGrayBB713.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
  4. Miscellaneous
    1. neurocnsgeneralanatomy.png
    2. neuroBrainstemGrayBB679.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    3. neuroBrainstemGrayBB682.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    4. neuroBrainstemGrayBB683.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    5. neuroBrainstemGrayBB684.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    6. neuroBrainstemGrayBB685.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    7. neuroBrainstemGrayBB686.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    8. neuroBrainstemGrayBB689.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    9. neuroBrainStemGrayBB719.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    10. neuroBrainStemRhomboidFossaGrayBB709.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
    11. neuroBrainstemGrayBB792.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)

VII. Signs: Brain Lesions

  1. Cranial Nerve dysfunction
  2. Ataxia
  3. Papillary abnormalities
  4. Nystagmus
  5. Hemiparesis
  6. Autonomic Dysfunction

VIII. 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
  4. Newton (1994) Am Fam Physician 49(4): 787-97 [PubMed]

Images: Related links to external sites (from Bing)

Related Studies (from Trip Database) Open in New Window

Ontology: Brain Stem (C0006121)

Definition (NCI) The part of the brain that connects the cerebral hemispheres with the spinal cord. It consists of the mesencephalon, pons, and medulla oblongata.(MeSH)
Definition (NCI_NCI-GLOSS) The part of the brain that is connected to the spinal cord.
Definition (NCI_CDISC) The part of the brain that connects the cerebral hemispheres with the spinal cord. It consists of the mesencephalon, pons, and medulla oblongata. (NCI)
Definition (MSH) The part of the brain that connects the CEREBRAL HEMISPHERES with the SPINAL CORD. It consists of the MESENCEPHALON; PONS; and MEDULLA OBLONGATA.
Definition (CSP) axial portion of the brain exclusive of the cerebellum and the forebrain; includes midbrain, medulla, and pons.
Concepts Body Part, Organ, or Organ Component (T023)
MSH D001933
SnomedCT 15926001
English Brain Stem, Brain Stems, Brainstem, Brainstems, brain stems, brain stem, brainstem, Truncus encephali, truncus cerebri, Truncus encephalicus, BRAIN STEM, BRAIN, BRAIN STEM, Truncus Cerebri, Cerebri, Truncus, Cerebrus, Truncus, Truncus Cerebrus, Brain stem, Brainstem structure, Brainstem structure (body structure)
Swedish Hjärnstam
Czech mozkový kmen
Finnish Aivorunko
Russian STVOL MOZGA, СТВОЛ МОЗГА
Japanese 脳幹
Croatian MOŽDANO DEBLO
Latvian Stumbrs, smadzeņu, Smadzeņu stumbrs
Polish Pień mózgu
Norwegian Truncus cerebri, Hjernestamme
Spanish Tronco Cerebral, Tallo Encefálico, Tallo Cerebral, Tronco del Encéfalo, estructura del tronco cerebral (estructura corporal), estructura del tronco cerebral, tronco del encéfalo, tronco encefálico, Tronco Encefálico
Portuguese Tronco Cerebral, Tronco do Encéfalo, Tronco Encefálico
French Tronc cérébral
German Hirnstamm, Truncus cerebri
Italian Tronco cerebrale
Dutch Hersenstam

Ontology: Structure of nucleus ambiguus (C0152400)

Definition (NCI) A very slender, longitudinal column of motor neurons in the ventrolateral medulla oblongata; its efferent fibres leave with the vagus and glossopharyngeal nerve and innervate the striated muscle fibres of the pharynx (including the musculus levator veli palatini) and the vocal cord muscles of the larynx.(On-line Medical Dictionary)
Concepts Body Part, Organ, or Organ Component (T023)
MSH D008526
SnomedCT 2083001
English Ambiguus nucleus, Amb, ambiguus nucleus, nucleus ambiguus, ambiguous nucleus, Nucleus innominatus, Ambiguous Nucleus, Nucleus, Ambiguous, Ambiguus, Nucleus, Nucleus Ambiguus, Nucleus ambiguus, Structure of nucleus ambiguus (body structure), Structure of nucleus ambiguus
Spanish estructura del núcleo ambiguo (estructura corporal), estructura del núcleo ambiguo, núcleo ambiguo

Ontology: Nucleus solitarius (C0175518)

Definition (NCI) Gray matter located in the dorsomedial part of the medulla oblongata associated with the solitary tract. The solitary nucleus receives inputs from most organ systems including the terminations of the facial, glossopharyngeal, and vagus nerves. It is a major coordinator of autonomic nervous system regulation of cardiovascular, respiratory, gustatory, gastrointestinal, and chemoreceptive aspects of homeostasis. The solitary nucleus is also notable for the large number of neurotransmitters which are found therein. (MeSH)
Definition (MSH) GRAY MATTER located in the dorsomedial part of the MEDULLA OBLONGATA associated with the solitary tract. The solitary nucleus receives inputs from most organ systems including the terminations of the facial, glossopharyngeal, and vagus nerves. It is a major coordinator of AUTONOMIC NERVOUS SYSTEM regulation of cardiovascular, respiratory, gustatory, gastrointestinal, and chemoreceptive aspects of HOMEOSTASIS. The solitary nucleus is also notable for the large number of NEUROTRANSMITTERS which are found therein.
Definition (CSP) gray matter located in the dorsomedial part of the medulla oblongata associated with the solitary tract; receives inputs from most organ systems including the terminations of the facial, glossopharyngeal, and vagus nerves; major coordinator of autonomic nervous system regulation of cardiovascular, respiratory, gustatory, gastrointestinal, and chemoreceptive aspects of homeostasis.
Concepts Body Part, Organ, or Organ Component (T023)
MSH D017552
SnomedCT 61538008, 280182005
English Solitary Nucleus, Nucleus Tractus Solitarii, Nucleus Solitarius, Nucleus Tractus Solitarius, Nucleus, Solitary, Nucleus of the Tractus Solitarius, solitary tract nucleus, NTS, Nucleus of solitary tract, Nuclei of solitary tract, Solitary tract nuclear complex, Solitary nucleus, Solitary nuclei, Nucleus tractus solitarius, nucleus of solitary tract, nucleus of the solitary tract, solitary nucleus, Sol, solitary nuclear complex, nucleus of tractus solitarius, Nucleus tracti solitarii, Nucleus fasciculus solitarius, Nuclei tractus solitarii, Nucleus tractus solitarii, Nucleus solitarius (body structure), Nuclei Tractus Solitarii, Nuclei Tractus Solitarius, Solitarius, Nuclei Tractus, Tractus Solitarius, Nuclei, Complex, Solitary Nuclear, Solitary Nuclear Complex, Nuclear Complices, Solitary, Solitary Nuclear Complices, Nuclear Complex, Solitary, Tractus Solitarius Nucleus, Nucleus of Solitary Tract, Nucleus of Tractus Solitarius, Solitarii, Nuclei Tractus, Solitarius Nucleus, Tractus, Tractus Solitarii, Nuclei, Complices, Solitary Nuclear, Nucleus of tractus solitarius, Structure of nucleus of tractus solitarius (body structure), Structure of nucleus of tractus solitarius, Nucleus solitarius, nucleus tractus solitarius, Nucleus of the Solitary Tract, Nucleus, Solitary Tract, Solitary Tract Nucleus
French Nucleus solitarius, Noyaux du tractus solitaire, Noyau du tractus solitaire, Noyau solitaire, Noyau du faisceau solitaire
Swedish Solitärkärna
Czech nucleus solitarius
Finnish Erillistumake
Russian SOLITARNOE IADRO, IADRO SOLITARNOE, NUCLEUS SOLITARIUS, СОЛИТАРНОЕ ЯДРО, ЯДРО СОЛИТАРНОЕ
Japanese 孤束核
Italian Nucleo del tratto solitario, Nucleo solitario
Polish Jądro samotne
Norwegian Nucleus tractus solitarii, Nucleus solitarius
Spanish núcleo solitario, núcleo solitario (estructura corporal), estructura del núcleo del tracto solitario (estructura corporal), estructura del núcleo del tracto solitario, núcleo del tracto solitario, Núcleo Solitario, Nucleus Solitarius
German Nucleus solitarius, Nucleus tractus solitarii
Dutch Nucleus solitarius
Portuguese Núcleo Solitário, Nucleus Solitarius

Ontology: Nucleus of origin of cranial nerve (C0926501)

Concepts Body Part, Organ, or Organ Component (T023)
English Nucleus of origin of cranial nerve, Nucleus originis