Peripaleocortex is one of two subtypes of
periallocortex
Periallocortex is one of three subtypes of allocortex, the other two subtypes being paleocortex and archicortex. The periallocortex is formed at transition areas where any of the other two subtypes of allocortex borders with the neocortex (which is ...
,
the other being
periarchicortex Periarchicortex is one of two subtypes of periallocortex, the other being peripaleocortex. It is formed at borders between archicortex (a subtype of allocortex) and isocortex and shows slow histological transition from the four-layered structure ty ...
.
Peripaleocortex is formed at borders between
isocortex
The neocortex, also called the neopallium, isocortex, or the six-layered cortex, is a set of layers of the mammalian cerebral cortex involved in higher-order brain functions such as sensory perception, cognition, generation of motor commands, s ...
(neocortex) and
paleocortex
In anatomy of animals, the paleocortex, or paleopallium, is a region within the telencephalon in the vertebrate brain. This type of cortical tissue consists of three cortical laminae (layers of neuronal cell bodies). In comparison, the neocortex ...
(a subtype of
allocortex
The allocortex or heterogenetic cortex, and neocortex are the two types of cerebral cortex in the brain. The allocortex is the much smaller area of cortex taking up just 10 %, the neocortex takes up the remaining 90 %. It is characterized by havi ...
). It shows slow
histological
Histology,
also known as microscopic anatomy or microanatomy, is the branch of biology which studies the microscopic anatomy of biological tissues. Histology is the microscopic counterpart to gross anatomy, which looks at larger structures vis ...
transition from the three-layered structure characteristic of paleocortex to the typical six-layered structure characteristic of isocortex.
The main peripaleocortex area is anterior
insular cortex
The insular cortex (also insula and insular lobe) is a portion of the cerebral cortex folded deep within the lateral sulcus (the fissure separating the temporal lobe from the parietal and frontal lobes) within each hemisphere of the mammalian bra ...
.
Peripaleocortex does not histologically transit directly to the true isocortex. Instead, at borders between peripaleocortex and isocortex, there are other transitional areas from the isocortex side, called
proisocortex Proisocortex or pro-isocortex is one of two subtypes of cortical areas in the areas belonging to the neocortex. The other subtype is termed the true isocortex. Proisocortical areas are transitional areas placed between areas of true isocortex and a ...
.
Thus, at borders between paleocortex and isocortex, there are two transitional areas. One transitional area, which is anatomically located closer to the paleocortex side and histologically, too, more resembling "true" paleocortex, is called peripaleocortex area.
Another transitional area, which is anatomically located close to the true isocortex side and histologically more resembling it too, is called proisocortex area.
References
{{neuroanatomy-stub
Cerebral cortex