Effect of Fragrance on Electroencephalographic Waves and Blood Pressure during Problemsolving Activity among Healthy College Students: A Cross-sectional Study

Abstract

Introduction: The influence of fragrance, such as perfumes and room fresheners, on the psycho-physiological activities of humans has been known for a long time. However, very few studies have been conducted to investigate its effects when a person is under stress. Aim: To determine the effect of fragrance on electroencephalographic waves and blood pressure during a problem-solving activity. Materials and Methods: This cross-sectional study was conducted among 55 college students aged 18-22 years in the electrophysiology laboratory of the Department of Physiology at Pondicherry Institute of Medical Sciences, Puducherry, India from May 2019 to June 2019. After obtaining a history and conducting an olfactory examination, participants were asked to be in the electrophysiology laboratory to record Electroencephalogram (EEG) and blood pressure before and after exposure to fragrance for five minutes. Data were statistically analysed using Fischer’s-exact test and paired t-test. Results: The study included 55 college students (38 males, 17 females) with a mean age of 19.46±1.004 years. EEG changes were compared at rest, including alpha waves (n=55), beta waves (n=55) during the problem-solving activity, and theta waves (n=55) during exposure to lavender fragrance. EEG changes were analysed using Fischer’s-exact test, and the results were statistically significant (p-value<0.001). The mean±Standard Deviation (SD) of Systolic Blood Pressure (SBP) during fragrance exposure (110±11.82 mmHg) vs solving the puzzle (123.44±15.97 mmHg) was significantly lower (p-value=0.048*). The mean±SD of Diastolic Blood Pressure (DBP) during fragrance exposure (74.44±11.27 mmHg) vs solving the puzzle (74.40±12.92 mmHg) was slightly higher, but not statistically significant (p-value=0.516). Conclusion: The present study demonstrated that the use of fragrance can have a relaxing effect on the mind and body, as it increases theta wave activity in the brain and significantly reduces SBP.