Measurement of olfactory threshold using an evoked potential technique.

A new device introducing brief pulses of odorised air synchronous with the inspiration of the test subject was developed. Responses to skatole were distinguishable as an evoked response by using the superimposition technique before averaging. The olfactory threshold measured by the chemosensory event-related potentials to olfactory stimulations according to our ascending method was found E-2 or E-1 and was equal to the detection olfactory threshold in each of the eight normal test subjects.