Cerebral arcuate fibers

The cerebral arcuate fibres, (a.k.a. the short arcuate fibres, short association fibres or U-fibres), are superficial cortico-cortical white-matter fibres that connect adjacent or nearby cortical regions within the same cerebral hemisphere. They lie immediately beneath the cortical grey matter–white matter boundary and follow the pattern of cortical folding, characteristically curving around the depths of the sulci to form U-shaped local connections.

Their organisation is more complex than a simple U-shaped connection between two neighbouring gyri. Shah et al. describe three components:

• intergyral fibres, which form deeper connections within the sulci;

• intragyral fibres, which extend towards the cortical surface and form the limbs of the U-shaped arrangement; and

• superficial gyral–gyral linkages, which connect adjoining or more distant gyri.

Some deeper intergyral fibres also connect with the long association fibre system, providing anatomical continuity between local cortical networks and more widely distributed cerebral networks.