Can i smell gas (or is it lilac)? Olfactory semantic deficits in mild cognitive impairment and Alzheimer's disease

Abstract

Olfactory decline represents one of the earliest signs of Alzheimer's disease (AD), and deficits in olfactory identification have now been identified in persons with amnestic mild cognitive impairment (aMCI). Whether the olfactory identification deficit in AD reflects underlying degraded semantic knowledge or lower-order olfactory deficits is uncertain. To address this question, we focused on the kinds of errors committed when participants were given a unirhinal olfactory identification task at baseline and after 1 year. The aim was to assess whether more errors were committed when the target smell is either semantically related or unrelated to the distracters. Fourteen AD, 13 aMCI, and 10 c..