Evoked and oscillatory neuromagnetic responses to sniffing odor in human subjects

We studied neuromagnetic responses to sniffing air and odor of lemon, lavender or soy sauce in two human subjects. Simple averaging of the data with respect to the onsets of the sniffs yielded odor-specific evoked responses over the right cortex with peak latency about 350 ms after the onsets. When the data were passed through band-pass filters centered around 48 Hz and of 320 ms in duration, rectified and then averaged, they yielded peaks, indicating transient oscillations, over the right frontal cortex with longer latency. We found such peaks in only 9 out of 26 experiments of sniffing odor, however.