Respiratory response toward olfactory stimuli might be an index for odor-induced emotion and recognition

Abstract

Olfaction is a unique sensory modality. Odor molecules reach olfactory receptors by inspiration, and odor information projects directly to limbic structures not through the thalamus. Odor stimuli thus induce respiratory changes, and simultaneously induce emotion and memory recognition via stimulation of olfactory-related limbic structures. We review the relations between respiration and olfaction, and between brain rhythm and respiration from our studies in normal subjects and in patients with Parkinson's disease who had been reported to have olfactory impairment.