During the past two decades, a considerable amount of research has been conducted in the USA, Europe and Japan to measure not only the psychometric effects of fragrance upon feelings, moods and emotions but also other related physiological responses.

The techniques applied are: electrical activity in the brain, physiological parameters such as heart rate, skin conductance and Cortisol level assays to measure response to fragrances and their effect on mood, memory and voluntary and non-voluntary behavior.