The olfactory trigone is a small triangular area in front of the anterior perforated substance.

This is a cholinergic bundle of nerve fibers posterior to the anterior perforated substance.

The diagonal band of Broca forms the medial margin of the anterior perforated substance.

(c) the inferior striate veins, which leave the corpus striatum through the anterior perforated substance.

Its anterior end is continuous with the lower part of the head of the caudate nucleus and with the anterior perforated substance.

The structures contained in it, from behind forward, are the posterior perforated substance, corpora mamillaria, tuber cinereum, infundibulum, and hypophysis.

Laterally it is continuous with the anterior perforated substances and anteriorly with a thin lamina, the lamina terminalis.

The gross anatomical structure is called the anterior perforated substance because, to the naked eye, it appears to be perforated by many holes (which are actually blood vessels).

The lateral olfactory stria is directed across the lateral part of the anterior perforated substance and then bends abruptly medialward toward the uncus of the hippocampal gyrus.

The medial olfactory stria turns medialward behind the parolfactory area and ends in the subcallosal gyrus; in some cases a small intermediate stria is seen running backward to the anterior perforated substance.

The primary concentration of cholinergic neurons/cell bodies that project to the neocortex are in the basal nucleus of Meynert which is located in the substantia innominata of the anterior perforated substance.

One definition includes the olfactory bulb, olfactory tract, anterior olfactory nucleus, anterior perforated substance, medial olfactory stria, lateral olfactory stria, parts of the amygdala and prepyriform area.

Paleocortex is present in the parahippocampal gyrus, olfactory bulb, accessory olfactory bulb, olfactory tubercle, piriform cortex, periamygdalar area, anterior olfactory nucleus, anterior perforated substance, and prepyriform area.

The communicating segment, or terminal segment, or C7, of the internal carotid artery passes between the optic and oculomotor nerves to the anterior perforated substance at the medial extremity of the lateral cerebral fissure.

Rosenthal's vein, or the cerebral basal vein (vena basalis): a vein that arises at the anterior perforated substance, passes backward and around the cerebral peduncle, and empties into the vein of Galen.

It consists of fibers that are said to arise in the parolfactory area, the gyrus subcallosus and the anterior perforated substance, and course backward in the longitudinal striae to the dentate gyrus and the hippocampal region.

This vessel, which then proceeds beyond the circle of Willis, is known as the middle cerebral artery, which sends branches into the anterior perforated substance at the medial extremity of the lateral cerebral fissure, and gives off its terminal or cerebral branches.

Thalamoperforating and thalamogeniculate or postero-medial ganglionic branches: a group of small arteries which arise at the commencement of the posterior cerebral artery: these, with similar branches from the posterior communicating, pierce the posterior perforated substance, and supply the medial surfaces of the thalami and the walls of the third ventricle.