A technique for assessing speech fluency used in neuropsychology to study speech productivity and executive functions. The subject is asked to name as many words beginning with a specific letter as possible (usually F, A, and S) in a limited amount of time, usually one minute for each letter. Proper nouns, numbers and forms of the same word are not allowed. Results depend on language skills, processing speed, and cognitive flexibility. The test is sensitive to frontal lobe dysfunction, dementia, and several other neurological and psychiatric conditions.