Prions are found throughout the brain. However, the signs and symptoms of the prion diseases vary according to the region of the brain in which they are most concentrated. In cases of FFI, prions are found in the greatest concentration in the thalamus.
Other prion diseases show the most concentration in the following areas of the brain:
- Kuru: Cerebellum
- Classic Creutzfeldt-Jakob Disease (CJD): Cerebral cortex
- Scrapie and bovine spongiform encephalopathy (BSE): Brain stem