Corticobasal degeneration

Corticobasal degeneration (CBD) is a sporadic progressive neurodegenerative disease associated with atrophy of the cerebral cortex and the basal ganglia. Onset is gradual. The first symptoms usually involve asymmetric changes in motor function, such as dystonia and myoclonus. Some patients experience alien hand syndrome. Language function can also be affected. CBD can expand to include extrapyramidal motor dysfunction (e.g. rigidity, tremor) and some cognitive dysfuntion (dementia). Upon autopsy, CBD brains present with frontal atrophy and glial abnormalities (astrocytic plaques). In addition, tau (a microtubule stabilizing protein that also aggregates in Alzheimer's disease) immunoreactivity can be detected in the white matter.

Many of the symptoms and pathology of CBD are similar to the more common disease, Progressive Supranuclear Palsy (PSP). Ballooned neurons are the most telling feature of CBD to allow distinction from PSP. Since CBD and Alzheimer's disease share tau pathology, scientists are hopeful that if a medical treatment that reduced tau aggregation was developed for Alzheimer's disease, it would also be useful for CBD patients. Such a treatment does not currently exist.