Can Semantic-Phonemic Discrepancy in Verbal Fluency Help to Detect Alzheimer’s Dementia?

Word retrieval difficulty is one of the early signs of Alzheimer’s disease, although such difficulties can also occur in typically aging. Therefore, it is necessary to find a task that differentiates the early stages of Alzheimer’s dementia from typically aging. Verbal fluency is a widely used measure to assess subjects’ cognitive processes following neurological damage, and often includes two subtests: semantic fluency, in which participants are asked to produce words which meet a semantic criterion, such as food or animals; and letter fluency, which requires participants to produce words starting with a certain letter, such as F or S. People with Alzheimer’s disease have more difficulty with semantic than letter fluency, although this pattern has also been shown in typically aging. In the current research, we investigate whether the semantic-letter discrepancy can differentiate Alzheimer’s dementia from typically aging.