I. CBS: core criteria | ||
Inclusion criteria (1 plus 2) | ||
 | 1. Progressive course | |
 | 2. At least three of the following: | |
 |  | a. Parkinsonism (bradykinesia or rigidity) |
 |  | b. Dystonia |
 |  | c. Myoclonus |
 |  | d. Impairment in voluntary limb control (alien limb) |
 |  | e. Cortical sensory deficit (symmetric/asymmetric) |
Exclusion criteria (all must be negative) | ||
 |  | a. Visual hallucinations |
 |  | b. REM sleep behavior disorder |
 |  | c. Cerebellar ataxia |
 |  | d. Prominent autonomic dysfunction |
 |  | e. Fluctuations in alertness |
 |  | f. Prominent rest tremor |
II. CBS- frontal variant: | ||
Inclusion criteria (meets core plus one of the following must be positive) | ||
 | 1. Agrammatism, non-fluent speech or motor speech deficits | |
 | 2. Apathy, disinhibition or loss of empathy | |
 | 3. Apraxia primarily affecting lower extremities | |
 | 4. Prominent executive dysfunction greater than memory or visuospatial impairment | |
III. CBS- temporoparietal variant: | ||
Inclusion criteria (meets core plus one of the following must be positive) | ||
 | 1. Logopenic aphasia [16] | |
 | 2. Elements of Gerstmann or Balint syndrome | |
 | 3. Episodic memory or visuospatial impairment greater than executive dysfunction |