Songklanakarin Journal of Science and Technology, 2004
The effects of aromas on humans are divided into physiological and psychological effects. The physiological effect acts directly on the physical organism, the psychological effect acts via the sense of smell or olfactory system, which in turn may cause a physiological effect. This paper reviews on the physiological effects which are used for the evaluation of the effects of aromas. Physiological parameters, i.e. heart rate blood pressure, electrodermal activity, electroencephalogram, slow potential brain waves (contingent negative variation), and eye blink rate or pupil functions, are used as indices for the measurement of the aroma effects.
Hongratanaworakit T. Physiological effects in aromatherapy. Songklanakarin J Sci Technol. 2004;26(1):117-125.