Cerebral white matter
Substantia alba cerebri
NervousOrgansHeadLeft and right
View left in 3D View right in 3D
- What it is
- The core of each hemisphere beneath the 2-4 mm grey cortex: bundles of myelinated axons (corona radiata, internal capsule, association and commissural fibres) whose fatty myelin makes it pale.
- Function
- Wires cortical areas to each other, to the other hemisphere and to the thalamus, brainstem and spinal cord.
- Size
- About 40% of brain volume; roughly 150,000-180,000 km of myelinated fibres in a young adult
- Clinical note
- Multiple sclerosis strips myelin from white-matter tracts; MRI shows the plaques as bright spots around the ventricles.