Gender Differences in Psychophysiological Responses to Herbal Plant Olfactory Stimuli: An Electroencephalogram Study

This study measured and compared the psychophysiological and psychological differences in the responses of men and women to olfactory stimuli from herbal plants. A total of 30 adult participants (mean age, 27.4 years; SD, ±8.97 years; 15 men and 15 women) were included and five different herbs were used: lavender, rosemary, sage, apple mint, and pelargonium. During olfactory activity, participants smelled each herb for 90 seconds while relying solely on their sense of smell and electroencephalography was used to measure brain wave changes. Subsequently, participants’ emotional states were assessed using the semantic differential method (SDM). The results indicated significant differences in the relative alpha, relative slow alpha, and relative low alpha frequencies in the prefrontal lobe (Fp1 and Fp2) for both genders (P < 0.05). Significant gender differences were observed in the relative beta, relative middle beta, ratio of sensorimotor rhythms-mid beta to theta frequencies in the occipital lobe (O1 and O2) (P < 0.05). The SDM results showed significant natural emotional responses in both genders after olfactory stimulation with herbal plants. Furthermore, compared with men, women exhibited more natural emotions to sage, apple mint, and pelargonium olfactory stimulation. These findings affirm the calming effects of olfactory stimulation with herbal plants for both genders, thus underscoring gender differences in preferences and psychological responses.