In today's world, Projection fiber has become a topic of great relevance and interest to a large number of people. From its impact on society to its influence on popular culture, Projection fiber has captured the attention of millions of individuals around the world. Whether through studies, debates or simply everyday conversations, Projection fiber has proven its importance in our daily lives. In this article, we will explore in depth the different facets of Projection fiber, from its origins to its evolution today, with the aim of shedding light on this fascinating and relevant topic.
Projection fiber | |
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Details | |
Identifiers | |
Latin | fibrae projectionis |
NeuroNames | 1218 |
TA98 | A14.1.00.018 |
TA2 | 5617 |
FMA | 76745 |
Anatomical terms of neuroanatomy |
The projection fibers consist of efferent and afferent fibers uniting the cortex with the lower parts of the brain and with the spinal cord. In human neuroanatomy, bundles of axons (nerve fibers) called tracts, within the brain, can be categorized by their function into association fibers, projection fibers, and commissural fibers.
In the neocortex, projection neurons are excitatory neurons that send axons to distant brain targets. Considering the six histologically distinct layers of the neocortex, associative projection neurons extend axons within one cortical hemisphere; commissural projection neurons extend axons across the midline to the contralateral hemisphere; and corticofugal projection neurons extend axons away from the cortex. That said, some neurons are multi-functional and can therefore be categorized into more than one such category.
The principal efferent fibers are:
The chief afferent fibers are:
This article incorporates text in the public domain from page 843 of the 20th edition of Gray's Anatomy (1918)
The nerve fibres which make up the white matter of the cerebral hemispheres are categorized on the basis of their course and connections. They are association fibres, which link different cortical areas in the same hemisphere; commissural fibres, which link corresponding cortical areas in the two hemispheres; or projection fibres, which connect the cerebral cortex with the corpus striatum, diencephalon, brain stem and the spinal cord.