Experiments have been done to link the autonomic responses (such as cardio-respiratory frequency, skin potential, resistance, temperature blood flow) and the subjective verbal responses resulting of induced odors (pleasant and unpleasant ones). Each individual has preferred channels responses in one or two autonomic parameters and the protocol and equipment allowed the verification of these reactions and the classification of the individuals by their specific reactions.
The autonomic responses are more informative because they are more diversified than the verbal responses and give information about the affective state of the subject exposed to an odor. Also in some cases autonomic responses can be registered while the subject is not reporting odor detection. The proposed method can make the link between the subjective reactions obtained by the autonomic responses and the

Links are being made between odor perception and the affective state of the person exposed to a specific odor; links that are not often made with verbal comments. This is interesting because this type of research could better understand the affective reaction to long unpleasant odor exposure.