Chemosensory-event-related potentials to olfactory stimulations.

Odorant pulses were introduced into the noses of 18 healthy volunteers by using a pressurized nasal spray. Just prior to the onset of inspiration, the spray tip was inserted 1 cm into the nostril as atraumatically as possible. The odorant pulse trigger was the subject's respiration. Responses to aerosolized skatole consisted mainly of a positive wave with a peak latency of 147.1 +/- 5.3 ms. These positive waves were distinguishable as an evoked response by employing curve superimpositions before and after averaging positive responses. In our cases, saturation of responses was found after 4-5 averagings with the response becoming most clear after 7-8 averagings. The response peak latency to more concentrated skatole was consistently shorter by 9-19 ms than that to 10% diluted skatole in all subjects tested.