The Effect of Body Position on Flavor Release and Perception: Implications for fMRI Studies

Abstract

Increasingly functional magnetic resonance imaging (fMRI) of the brain is being used to assess the cortical response to flavor perception. fMRI requires the subject to adopt a supine position; hence, if the results from such experiments are to be meaningfully extrapolated to flavor perception, it is pertinent to establish whether body position has a significant impact on consumers’ sensitivity to flavor. Body position is known to impact on some aspects of sensory perception, but no studies have reported the effect of body position on retronasal flavor perception. In this study, A/Not-A tests (ISO 1987), together with sureness ratings, were performed to evaluate subjects’ (n = 10) ability to differentiate between two subtly different emulsion samples under two conditions: seated in a quiet sensory booth environment and supine in a 3 T fMRI scanner mimicking real scanning conditions. In vivo volatile release was also measured in both seated and supine positions using atmospheric pressure chemical ionization mass spectrometry. Results indicated that body position had some impact on volatile release, but no overall effect on subject’s ability to discriminate between the two samples was observed. Consequently, brain imaging data collected in this context at least would have direct relevance to sensory perception data. However, more extensive research is required to fully understand the impact of body position on flavor perception and release.