ABSTRACTMentha suaveolens Ehrh. is an aromatic herb, traditionally used in the Mediterranean areas. Our objective was to evaluate the effect of inhalation of a commercial essential oil of M. suaveolens on human electroencephalographic (EEG) activity according to gender differences by measuring EEG power spectrum changes in healthy participants. Piperitenone oxide (55.60%) was the most abundant component in the essential oil. Our findings indicated that the inhalation of M. suaveolens essential oil produced different EEG power spectrum changes as well as affected different brain regions between genders. It could be concluded that the inhalation of M. suaveolens essential oil significantly changed the EEG wave activity according to gender and these changes may cause some alterations in the psychophysiological functions of humans. Hence, M. suaveolens essential oil may be utilized in aromatherapy for improving the psychophysiological functions of humans.KEYWORDS: electroencephalographyessential oilgenderMentha suaveolensinhalation AcknowledgmentsThe authors thank Tonia Strano for her skillful technical assistance for GC-MS analysis and Flora Srl for supplying the essential oil subject of this study.Disclosure statementNo potential conflict of interest was reported by the author(s).