Answer and Discussion of Quiz Set: N-025

6.    This image is taken from the occipital lobe. What is the structure in between the two arrows?

Link to Online Slide

A.  Fimbria

B.  Anterior commissure

C.  Posterior commissure

D.  Indusium griseum

E.  Tapetum

Answer and Discussion: The answer is (E). The structure being illustrated here is the tapetum of corpus callosum (tapetum corporis callosi). The tapetum (tapete means carpet in latin) is a layer of fibers of the corpus callosum that fans out as a thin layer of fibers on the superolateral aspect of the occipital horn of the lateral ventricle.It is formed primarily by decussating fibers in the splenium of the corpus callosum that arch over the atrium of the lateral ventricle and course inferiorly in the lateral wall of the posterior, and somewhat into the temporal horns, of the lateral ventricle.

Reference:

Sarikcioglu L, Ozsoy U, Unver G. Tapetum corporis callosi: carpet of the brain. J Hist Neurosci. 2007 Oct-Dec;16(4):432-4.