An experimental paradigm for studying EEG correlates of olfactory discrimination

Electroencephalography (EEG) correlates of olfaction are of fundamental and practical interest for many reasons. In the field of neural technologies, olfactory-based brain-computer interfaces (BCIs) represent an approach that could be useful for neurorehabilitation of anosmia, dysosmia and hyposmia. While the idea of a BCI that decodes neural responses to different odors and/or enables odor-based neurofeedback is appealing, the results of previous EEG investigations into the olfactory domain are rather inconsistent, particularly when non-primary processing of olfactory signals is concerned. Here we developed an experimental paradigm where EEG recordings are conducted while a participant executes an olfaction-based instructed-delay task. We utilized an olfactory display and a sensor of respiration to deliver odors in a strictly controlled fashion. We showed that with this approach spatial and spectral EEG properties could be analyzed to assess neural processing of olfactory stimuli and their conversion into a motor response. We conclude that EEG recordings are suitable for detecting active processing of odors. As such they could be integrated in a BCI that strives to rehabilitate olfactory disabilities or uses odors for hedonistic purposes.

Automated summary

Electroencephalography (EEG) correlates of olfaction have both fundamental and practical importance. Olfactory-based brain-computer interfaces (BCIs) have the potential to aid in neurorehabilitation for olfactory disorders. However, previous EEG investigations in the olfactory domain have yielded inconsistent results. In this study, we developed an experimental paradigm to analyze the neural processing of olfactory stimuli using EEG recordings during an instructed-delay task. Our findings suggest that EEG recordings can effectively detect active processing of odors, making them suitable for integration in olfactory BCIs.