Chemosensory Perception

, Volume 5, Issue 1, pp 46–54 | Cite as

Beyond Self-report: Brain Imaging at the Threshold of Odor Perception



Odorants exert their effects at many levels. Most often, these stimuli are well above detection threshold and allow the investigator to use self-report or behavioral techniques to evaluate odor effects. There are, however, considerable data demonstrating effects for odor stimuli that are below sensory thresholds or are undetected by subjects. In these cases, self-report is of little use, and brain imaging has been very effective in helping to explain these findings. This paper reviews the problem of low-intensity odors and the application of a wide variety of brain imaging techniques to research on this phenomenon. Finally, a model of undetected odor effects and brain imaging is presented to help simplify the variations in nomenclature that are used to describe this field.


Brain imaging fMRI EEG ERP Smell Olfaction Odor Threshold Consciousness Subliminal Attention 



The author is indebted to W. Whiting, D. Small, S. Warrenburg, B. Lorig, and an anonymous reviewer for their suggestions and comments on this manuscript.


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Copyright information

© Springer Science + Business Media, LLC 2012

Authors and Affiliations

  1. 1.Washington and Lee UniversityLexingtonUSA

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