Effects of Aroma Essential Oil Inhalation on Autonomic Nerve System Response, Electroencephalogram and Concentration

Purpose: This study was an experimental research study to examine the effects of aroma essential oil inhalation on autonomic nerve system response, electroencephalogram and concentration.Methods: The participants were 92 healthy adults: 32 in the experimental group, 30 in the placebo group, and 30 in the control group. In the experimental group, lemon and rosemary oil were mixed in a ratio of 4: 1, and 0.1 ml was dropped on gauze and then naturally inhaled for a total of 30 minutes. The application for the placebo group was 0.9% saline solution, and for the control group, no treatment. To determine the effects, the autonomic nervous system response was measured by applying Canopy 9 Plus 4.0 before the experiment and at 10, 20, and 30 minutes after the experimental application, and an electroencephalogram was taken using QEEG-8. The computerized neurocognitive function test for measuring concentration was given before the experiment and at 30 minutes after the treatment.Results: There were no significant differences in the homogeneity tests for general characteristics and for the dependent variables prior to the experiment. There was a significant difference in sympathetic nervous activity between the experimental group, placebo group, and control group (F=3.78, p=.027), and the experimental group had higher sympathetic nervous activity than the control group. There was no statistically significant difference on the electroencephalogram between the ⍺ and beta waves of the three groups. The Stroop Color-Word interference test (color) of the three groups for concentration measurement was significantly different between pre test and at 30 minutes after the treatment (F=7.40, p=.001), and the score for the experimental group increased compared to the control group.Conclusion: The findings showed that the inhalation of aroma essential oil activated the sympathetic nervous system and partially increased the level of concentration.