[1][2] CBS is typically caused by the deposit of tau proteins forming in different areas of the brain.
[6] The Armstrong criteria were proposed in 2013; the accuracy of these is limited and further research is needed.
[7] Symptoms may be symmetric or asymmetric, with one or more of the following:[citation needed] The onset is insidious with gradual progression, lasting one year or more, with no exclusion criteria present.
[8] Probably sporadic CBS is more likely if there are two of: The diagnosis is excluded if there is evidence of: The diagnostic criteria for clinical use may result in a misdiagnosis of other tau-based diseases.
[7] Other degenerative pathologies that can cause corticobasal syndrome include: The symptoms of classic CBS differ from CBD in that CBD also includes cognitive deficits in the executive functions.