Terminal nerve

From Infogalactic: the planetary knowledge core
(Redirected from Cranial nerve zero)
Jump to: navigation, search
Cranial nerve zero
File:Lawrence 1960 1.3.png
Left The terminal nerve as it is shown on the ventral side of a dog-fish brain. (Topmost label)
Details
Latin nervus terminalis
Identifiers
TA Lua error in Module:Wikidata at line 744: attempt to index field 'wikibase' (a nil value).
TH {{#property:P1694}}
TE {{#property:P1693}}
FMA {{#property:P1402}}
Anatomical terminology
[[[d:Lua error in Module:Wikidata at line 863: attempt to index field 'wikibase' (a nil value).|edit on Wikidata]]]

Lua error in package.lua at line 80: module 'strict' not found. The terminal nerve, or cranial nerve zero, was discovered by German scientist Gustav Fritsch in 1878 in the brains of sharks. It was first found in humans in 1913.[1] A 1990 study has indicated that the terminal nerve is a common finding in the adult human brain.[2][3] The nerve has been called by other names, including cranial nerve XIII, Zero Nerve, Nerve N,[4] and NT.[5]

Structure

File:Fritsch dogfish shark brain.png
The original images (1878) of Fritsch's dogfish shark brain showing the nerve marked by an asterisk.

The terminal nerve appears just anterior of the other cranial nerves bilaterally as a microscopic plexus of unmyelinated peripheral nerve fascicles in the subarachnoid space covering the gyrus rectus. This plexus appears near the cribriform plate and travels posteriorly toward the olfactory trigone, medial olfactory gyrus, and lamina terminalis.[2]

The nerve is often overlooked in autopsies because it is unusually thin for a cranial nerve, and is often torn out upon exposing the brain.[4] Careful dissection is necessary to visualize the nerve. Its purpose and mechanism of function is still open to debate; consequently, nerve zero is often not mentioned in anatomy textbooks.[1]

Development

The zebrafish has been used as a developmental model in recent research.[6]

The connections between the terminal nerve and the olfactory system have been extensively studied in human embryos. It was found to enter the brain at stages 17 and 18 from olfactory origins.}[7]

Function

Although very close to[8] (and often confused for a branch of) the olfactory nerve, the terminal nerve is not connected to the olfactory bulb, where smells are analyzed. This fact suggests that the nerve is either vestigial or may be related to the sensing of pheromones. This hypothesis is further supported by the fact that the terminal nerve projects to the medial and lateral septal nuclei and the preoptic areas, all of which are involved in regulating sexual behavior in mammals.[1]

Additional images

See also

References

  1. 1.0 1.1 1.2 Lua error in package.lua at line 80: module 'strict' not found.
  2. 2.0 2.1 Lua error in package.lua at line 80: module 'strict' not found.
  3. Lua error in package.lua at line 80: module 'strict' not found.
  4. 4.0 4.1 Lua error in package.lua at line 80: module 'strict' not found.
  5. Lua error in package.lua at line 80: module 'strict' not found.
  6. Lua error in package.lua at line 80: module 'strict' not found.
  7. Lua error in package.lua at line 80: module 'strict' not found.
  8. Lua error in package.lua at line 80: module 'strict' not found.

External links

  • Lua error in package.lua at line 80: module 'strict' not found.
  • Lua error in package.lua at line 80: module 'strict' not found.