A Registered Cohort Study on Color Discrimination Deficit Associated With Neurodegenerative Disorders.

Inclusion Criteria: * All patients underwent extensive clinical examination including thorough neurological and somatic examination by a specialized neurologist or geriatrician and extensive neuropsychological examination by a trained psychologist. AD was diagnosed according to the NINCDS-ADRDA criteria. Exclusion Criteria: * We excluded individuals with noncompensated somatic illnesses, a history of a psychiatric disorder, color blindness, ophthalmological pathology, severe cranial trauma, focal neurological signs or magnetic resonance imaging examinations suggestive of cerebrovascular disturbances.