This study measured psychological and physiological signals, such as brain waves and blood pressures, of a group of students before and after they inhaled the essence of Hinoki Cypress (Chamaecyparis obtusa), containing terpenoid, the main ingredient of forest bath, which recently has been drawing attention due to its reported effectiveness. In addition to that, psychological tests, such as olfactory sensibility evaluation, as well as short-term memory, concentration, stress, and arousal tests, were likewise conducted in this study.

In summary, when the subjects inhaled the essence of cypress oil, their stresses were reduced and their memory and concentration improved under even working condition as well as under a stable condition. The fragrance, however, more effectively reduced the stress of the female subjects than that of the male subjects.

References

1. Aggleton, J.P. 1993. The contribution of the amygdala to normal and abnormal emotional staes. Tresds Neurosci 16:328-335.
2. Yasutaka, K and S. Wataru, et al. 2001. Frontal midline theta rhythm is correlated with cardiac autonomic activities during the performance of an attention demanding meditation procedure. Cognitive Brain Research 1(11):281-287
3. Andreassi, J.H. 1995. Psychophysiology: Human behavior and physiolodical response. Lawrence Erlbaum Associates.
4. Aoshima, H., S.J. Hossain, H. Koda. and Y. Kiso. 2002. Relaxational effects by whiskey aroma. Aroma Research 12(3):327-333.
5. Harmon-Jones, E. and J.B. Allen. 1997. Behavioral cativation sensitivity and resting frontal EEG asymmetry. J. Abnormal Psychology 106:159-163.
6. McCarley, R.W., M.E. Shenton, B.F. O'donnell, S.R. Faux, and P.G. Nestor. 1993. Auditory P300 abnormalities and left posterior superior temporal gyrus volume reduction in schixophrenia. Arch. Gen. psychiatry 50:19-197.