Few studies have examined the presence of linguistic deficits in the preclinical phase of Alzheimer's disease (AD). A total of 19 healthy carriers of the E280A presenilin-1 gene mutation in chromosome 14 and 21 noncarrier family members from Antioquia, Colombia, were administered a neurolinguistic evaluation of lexical-semantic processes. Both groups were similar in age, educational level, and gender. Carriers scored significantly lower than noncarriers on naming of famous faces. Cognitive changes in lexical-semantic tasks can be detected before the clinical diagnosis of probable familial AD, and a neurolinguistic evaluation may be a useful tool in the early clinical diagnosis of sporadic AD as well.