The posterior perforated substance (PPS) is a layer of gray matter which is pierced by small apertures for the transmission of

blood vessels Blood vessels are the tubular structures of a circulatory system that transport blood throughout many animals’ bodies. Blood vessels transport blood cells, nutrients, and oxygen to most of the tissues of a body. They also take waste an ...

. Its inferior part lies on the

ventral Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

aspect of the medial portions of the tegmenta and contains the

interpeduncular nucleus The interpeduncular nucleus (IPN) is an unpaired, ovoid group of neurons at the base of the midbrain tegmentum. In the midbrain it lies below the interpeduncular fossa. As the name suggests, the interpeduncular nucleus lies ''in between'' the cere ...

; its superior part forms part of the floor of the

third ventricle The third ventricle is one of the four connected cerebral ventricles of the ventricular system within the mammalian brain. It is a slit-like cavity formed in the diencephalon between the two thalami, in the midline between the right and lef ...

. The PPS is situated between the two

cerebral peduncle The cerebral peduncles (In Latin, ''ped-'' means 'foot'.) are the two stalks that attach the cerebrum to the brainstem. They are structures at the front of the midbrain which arise from the ventral pons and contain the large ascending (sensor ...

s in the

midbrain The midbrain or mesencephalon is the uppermost portion of the brainstem connecting the diencephalon and cerebrum with the pons. It consists of the cerebral peduncles, tegmentum, and tectum. It is functionally associated with vision, hearing, mo ...

. and posterior to the two

mammillary bodies The mammillary bodies also mamillary bodies, are a pair of small round brainstem nuclei. They are located on the undersurface of the brain that, as part of the diencephalon, form part of the limbic system. They are located at the ends of the ant ...

. It is perforated by the posteromedial central arteries – branches of the posterior cerebral arteries en route to the

thalamus The thalamus (: thalami; from Greek language, Greek Wikt:θάλαμος, θάλαμος, "chamber") is a large mass of gray matter on the lateral wall of the third ventricle forming the wikt:dorsal, dorsal part of the diencephalon (a division of ...

and

basal ganglia The basal ganglia (BG) or basal nuclei are a group of subcortical Nucleus (neuroanatomy), nuclei found in the brains of vertebrates. In humans and other primates, differences exist, primarily in the division of the globus pallidus into externa ...

Additional images

File:Human brainstem anterior view 2 description.JPG, Human brainstem anterior view

References

External links

* * Central nervous system {{Portal bar, Anatomy

See also

Additional images

References

External links