A methodological investigation of a flexible surface MRI coil to obtain functional signals from the human olfactory bulb

Abstract Background Mammalian olfaction begins with transduction in olfactory receptors, continues with extensive processing in the olfactory bulb, and culminates in cortical representation. Most rodent studies on the functional neuroanatomy of olfaction have concentrated on the olfactory bulb, yet whether this structure is tuned only to basic chemical features of odorants or also to higher-order perceptual features is unclear. New method Whereas studies of the human brain can typically uncover involvement of higher-order feature extraction, this has not been possible in the case of the olfactory bulb, inaccessible to fMRI. The present study examined whether a novel method of acquisition using a facial coil could overcome this limitation. Results A series of experiments provided preliminary evidence of odor-driven responses in the human olfactory bulb, and found that these responses differed between individuals. Comparison with existing methods and conclusions The present preliminary technical achievement renders possible to design novel human odor fMRI studies by considering the olfactory system from the olfactory bulb to associative areas.