Design and Evaluation of an Olfactometer for fMRI Studies

doi:10.11938/cjmr20140403

Abstract

Abstract:

We developed a computer-controlled olfactometer for delivering odors for functional magnetic resonance imaging (fMRI) experiments. The olfactometer is consisted of an air transport system and a control system. Odors are produced and delivered by the air transport system, in which air flow first passes through liquid mixed with odorants in gas-washing bottles and then is delivered to the test subjects. The control system provides a user interface for
operating the device and controlling solenoid valves. The system is based on virtual instrumentation technology, and the software for it is written in LabVIEW. The device was tested on a Siemens 3.0 T MRI scanner. Block-design fMRI data were collected from one healthy subject who was stimulated with two odors, isoamyl acetate and pyridine. The raw fMRI data were processed with Matlab-based SPM8 and MarsBaR toolbox. Region-of-interest (ROI)-based analysis was performed for the left orbitofrontal cortex and left insula. It was found that the signal changes in the two ROIs were basically in compliance with the stimulation paradigm, but the signal changes induced by pyridine were more robust than that produced by isoamyl acetate stimulation. In the same ROI, the signal intensity changes caused by pyridine were higher than that induced by isoamyl acetate.

Key words: fMRI, olfactometer, olfactory, stimulation

CLC Number:

WANG Xiao-guan1–3，WANG Hui3，CHANG Yan3，XU Ya-jie3，ZHANG Guang-cai3，JIANG Rui-rui1–3，YANG Xiao-dong3*. Design and Evaluation of an Olfactometer for fMRI Studies[J]. Chinese Journal of Magnetic Resonance, 2014, 31(4): 477-487.

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