Association fiber

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Association fiber
Gray751.png
Diagram showing principal systems of association fibers in the cerebrum.
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Dissection of cerebral cortex and brainstem showing association fibers and insular cortex after removal of its superficial grey matter
Details
Identifiers
Latin Fibrae associationis telencephali
Dorlands
/Elsevier
f_05/
TA A14.1.00.016
A14.1.09.553
FMA 75241
Anatomical terms of neuroanatomy

Association fibers are axons that connect cortical areas within the same cerebral hemisphere.[1]

In human neuroanatomy, axons within the brain, called fibers, can be categorized on the basis of their course and connection into association fibers, projection fibers, and commissural fibers.[1]

The association fibers unite different parts of the same cerebral hemisphere, and are of two kinds: (1) those connecting adjacent gyri, short association fibers; (2) those passing between more distant parts, long association fibers.

Short association fibers[edit]

Many of the short association fibers (also called arcuate or "U"-fibers) lie immediately beneath the gray substance of the cortex of the hemispheres, and connect together adjacent gyri.[2] Some pass from one wall of the sulcus to the other.[2]

Long association fibers[edit]

The long association fibers connect the more widely separated gyri and are grouped into bundles.[2] They include the following:

Name From To
uncinate fasciculus frontal lobe temporal lobe
cingulum cingulate gyrus entorhinal cortex
superior longitudinal fasciculus frontal lobe occipital lobe
inferior longitudinal fasciculus occipital lobe temporal lobe
vertical occipital fasciculus inferior parietal lobule fusiform gyrus
occipitofrontal fasciculus occipital lobe frontal lobe
fornix hippocampus mammillary bodies
Arcuate fasciculus frontal lobe temporal lobe

Diffusion tensor imaging is a non-invasive method to study the course of association fibers.

See also[edit]

References[edit]

  1. ^ a b Standring, Susan (2005). Gray's Anatomy: The Anatomical Basis of Clinical Practice (39th ed.). Churchill Livingstone. p. 411. ISBN 9780443071683. 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. 
  2. ^ a b c Standring, Susan (2005). Gray's Anatomy: The Anatomical Basis of Clinical Practice (39th ed.). Churchill Livingstone. p. 411. ISBN 9780443071683. Association fibres may be either short association (arcuate or 'U') fibres, which link adjacent gyri, or long association fibres, which connect more widely separated gyri. Short association fibres may be entirely intracortical. Many pass subcortically betweena adjacent gyri, some merely pass from one wall of a sulcus to the other. Long association fibres are grouped into bunbles, ... 

External links[edit]