To determine the type of fibre depicted in the image of the internal capsule, let's analyze the characteristics and functions of each type of neural fiber:
- Projection fibres: These fibres connect different regions of the central nervous system. They carry information from the cerebral cortex to lower brain regions or from lower regions to the cortex. The internal capsule, which consists of fibres extending to and from the cerebral cortex, is a primary area where projection fibres are located.
- Short association fibres: These fibres connect adjacent gyri within the same hemisphere of the brain. They are primarily involved in intra-hemispheric communication and are found in the cortical areas, not typically represented in the internal capsule.
- Long association fibres: These fibres connect different lobes within the same hemisphere of the brain, allowing long-distance communication. Like short association fibres, they are located in the cortical areas rather than the internal capsule.
- Commissural fibres: These fibres connect corresponding areas of the two hemispheres of the brain. Examples include the corpus callosum and anterior commissure, which are not associated with the internal capsule.
Given this information, the fibres within the internal capsule are best described as projection fibres.