Neural processing of odor-associated words: an fMRI study in patients with acquired olfactory loss

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

Abstract

Perception of olfactory information is mediated by both bottom-up (from molecules to perception) and top-down (e.g. cross-modal associative learning) processes. Acquired olfactory loss is a frequent disorder which is typically due to alterations in the bottom-up pathway. However, it is unclear how the top-down modulation of olfactory processing is affected by olfactory impairment. Our study aimed to investigate the top-down olfactory processing in patients with acquired olfactory loss and participants with normal olfaction. Using functional MRI, brain responses from 14 patients and 16 healthy controls were assessed during a task of expectation and reading of words with strong olfactory associations (OW) (e.g. "Rose") and control words with little to no olfactory associations (CW) (e.g. "Door"). The expectation but not reading of the OW was associated with stronger neural activation in the angular gyrus and the inferior frontal gyrus extending to insula in the group of patients. During OW reading, the brain activation in the left OFC and right putamen was negatively correlated with odor identification score in patient and control groups, respectively. In addition, the duration of olfactory loss among patients was positively associated with activation in the left putamen during OW expectation. Taken together, these findings suggest an enhanced top-down olfactory modulation in patients with olfactory loss.

Details

Original languageEnglish
Pages (from-to)1164-1174
Number of pages11
JournalBrain imaging and behavior
Volume14
Issue number4
Publication statusPublished - Aug 2020
Peer-reviewedYes

External IDs

Scopus 85062468853
ORCID /0000-0001-9713-0183/work/146645358

Keywords

Keywords

  • Brain/diagnostic imaging, Brain Mapping, Humans, Magnetic Resonance Imaging, Odorants, Olfaction Disorders/diagnostic imaging, Smell