posterior cerebral commissure

pos·ter·i·or ce·re·bral com·mis·sure

(pos-tēr'ē-ŏr ser'ĕ-brăl kom'i-shŭr) A thin band of white matter, crossing from side to side beneath the habenula of the pineal body and over the aditus ad aqueductum cerebri; it is largely composed of fibers interconnecting the left and right pretectal regions and related cell groups of the midbrain; dorsally, it marks the junction of the diencephalon and mesencephalon.
Synonym(s): commissura posterior cerebri [TA] .