Calcarine fissure

Infobox Brain
Name = PAGENAME
Latin = sulcus calcarinus, fissura calcarina
GraySubject = 189
GrayPage = 820


Caption = Medial surface of left cerebral hemisphere. ("Calcarine fissure" visible at left.)


Caption2 = Coronal section through posterior cornua of lateral ventricle. (Label for "Calcarine fissure" visible at bottom.
IsPartOf = Occipital lobe
Components =
Artery = calcarine branch of medial occipital artery
Vein =
BrainInfoType = hier
BrainInfoNumber = 25
MeshName =
MeshNumber =
DorlandsPre = s_28
DorlandsSuf = 12768398
The calcarine fissure (or calcarine sulcus) is an anatomical landmark located at the very caudal end of the medial surface of the brain.

Anatomy

The calcarine sulcus begins near the occipital pole in two converging rami and runs forward to a point a little below the splenium of the corpus callosum, where it is joined at an acute angle by the medial part of the parietooccipital fissure. The anterior part of this fissure gives rise to the prominence of the calcar avis in the posterior cornu of the lateral ventricle.

Function

The calcarine sulcus is where the primary visual cortex is concentrated. The central visual field is located in posterior portion of the calcarine sulcus and the peripheral visual field in the anterior portion. It is interesting to note, though unsurprising, that the amount of cortex dedicated to each square millimeter of the visual field is highly non-proportional; significantly more cortex is dedicated to the processing of information originating from the fovea than other locations. [cite journal |author=Wong A, Sharpe J |title=Representation of the visual field in the human occipital cortex: a magnetic resonance imaging and perimetric correlation |journal=Arch. Ophthalmol. |volume=117 |issue=2 |pages=208–17 |year=1999 |pmid=10037566] This is known as cortical magnification.

References

External links

*
* http://www2.umdnj.edu/~neuro/studyaid/Practical2000/Q31.htm
* - "The Visual Pathway from Below"