Pallium (neuroanatomy)

Part of the brain in vertebrates

The pallium is a significant structure in the brain of vertebrates, playing a crucial role in the processing of sensory information and the execution of complex behaviors. It is a layered structure that is particularly well-developed in mammals, where it forms the cerebral cortex.

Structure

The pallium is divided into several regions, each with distinct functions and characteristics. In mammals, the pallium is organized into the neocortex, archicortex, and paleocortex.

Neocortex

The neocortex is the most evolved part of the pallium and is responsible for higher-order brain functions such as sensory perception, cognition, and generation of motor commands. It is characterized by its six-layered structure.

Archicortex

The archicortex includes structures such as the hippocampus, which is involved in memory formation and spatial navigation. It has a simpler three-layered structure compared to the neocortex.

Paleocortex

The paleocortex is involved in olfactory processing and includes the olfactory bulb and piriform cortex. It also has a three-layered structure.

Function

The pallium is involved in a wide range of functions, from basic sensory processing to complex cognitive tasks. In mammals, the expansion and elaboration of the pallium have allowed for advanced capabilities such as language, abstract thought, and problem-solving.

Evolution

The evolution of the pallium is a key factor in the development of complex behaviors in vertebrates. In non-mammalian species, such as birds and reptiles, the pallium is less differentiated but still plays a crucial role in sensory processing and behavior.

Diagram of vertebrate pallium

Avian Pallium

In birds, the pallium is organized differently compared to mammals. It includes structures such as the nidopallium and mesopallium, which are involved in complex behaviors and cognitive functions.

Differences in neuronal specification and migration patterns

Development

The development of the pallium involves complex processes of neuronal specification and migration. During embryonic development, neural progenitor cells differentiate into various types of neurons that populate the different layers of the pallium.

Related pages

• Cerebral cortex
• Hippocampus
• Olfactory bulb
• Neocortex