Methods in smell perception research

In olfaction the absolute and differential threshold for odor perception are explored using the following methods:
 * Method of limits
 * Method of adjustment
 * Method of constant stimuli

The stimuli in the past was usually provided by a Zwaardemaker olfractometer, a type of glass tube by which an odorant was introduced into the nose. The amount of odour being calibrated by the length of the tube. This was a device developed in 1888 by the Dutch physiologist, Hendrick Zwaardemaker who also developed the Zwaardemaker smell system.

Papers

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