Non-figurative coloured arrangements, towards a new tool to visually facilitate odour imagery?

Odour imagery, the ability to experience smell when an appropriate stimulus is absent, has widely been documented as being particularly difficult. However, previous studies have shown the beneficial effect of visual cues ( e.g. pictures or words) to facilitate performance in numerous tasks of olfactory nature. Therefore, the use of visual cues to evoke odours seems relevant. In this study, our interest is directed towards non-figurative coloured arrangements, which result from a patented technology and aim at chromatically representing any smell from its chemical composition. We recorded and compared hemodynamic responses during odour imagery facilitated by non-figurative coloured arrangements and pictures using functional magnetic resonance imaging. Our findings reveal that the use of non-figurative coloured arrangements during odour imagery solicits olfactory and non-olfactory brain regions which have roles mainly in olfactory processing, multimodal integration. Moreover, very similar cortical activity was found between the use of non-figurative coloured arrangements and pictures during odour imagery. Overall, non-figurative coloured arrangements could become a robust tool to visually evoke odours without requiring prior familiarity with the depicted odour. Future studies are needed to determine the relationships between brain activation and vividness of the generated odour images as well as the necessary mental workload.