Topographical EEG Maps of Human Responses to Odorants — A Preliminary Report

EEG recordings from 19 scalp loci from 10 young adult females were used to assess the physiological response to seven odorants (birch tar, galbanum, heliotropine, jasmine, lavender, lemon, and peppermint). The odorants were randomly delivered to a face mask via valve-selectable tubing pathways that diverted air flow through one of seven sample vials or through an empty vial to serve as a control. Subjects first scored the odors on a scale of 1–9 along continua for sleep-arousal, intensity, and pleasantness. Topographic maps were constructed from the amplitude spectra in the frequency bands of delta (1–4 Hz), theta (4–8 Hz), alpha (8–13 Hz), and beta (13–30 Hz). Eight seconds of representative and artifact-free EEG were selected for FFT analysis before onset of stimulus delivery, and at three times after stimulus onset. EEG was also quantified at 30 seconds after stimulus termination.