**4.6 Neuromodulation effects**

The aroma of scented tea can relieve depression and reduce anxiety and also improve concentration, relieve physical stress and improve work efficiency. Studies have shown that inhaling the aroma of jasmine scented tea can improve the rate of simple mental arithmetic by 10% and alleviate tachycardia [72]. Kyoko et al. [73] showed that inhaling the aroma of jasmine scented tea for 5 min can significantly reduce heart rate, making people feel calm and energetic. Another study reported that the aroma of jasmine scented tea contained (R)-(−)-linalool, which plays a sedative role in human autonomic nervous activity and emotional state. Li et al. [29] conducted a study on the intervention effect of rose scented tea on postpartum depression and found that rose scented tea could reduce the Edinburgh Postpartum Depression Scale score in patients with postpartum depression and alleviate related symptoms to varying degrees. Subsequently, Zhai et al. [74] conducted a comparative study on rose scented tea and sweet orange essential oil, which has sedative effects. Inhalation of rose scented tea and sweet orange essential oil using aromatherapy lamps significantly reduced blood pressure and heart rate and rose scented tea was better at relieving the systolic blood pressure. Scented tea contains high amounts of volatile substances, which together form the unique aroma of scented tea. Among these, hydrocarbons, alcohols, esters and phenolic compounds are volatilised after brewing and heating the scented tea. These substances are absorbed by the capillaries of the lungs and then transported to the whole body via the blood, relieving the muscles and brain cells of the body.
