An Olfactory Stimulus Modifies Nighttime Sleep in Young Men and Women

Abstract

Aromatherapy is an anecdotal method for modifying sleep and mood. However, whether olfactory exposure to essential oils affects night-time objective sleep remains untested. Previous studies also demonstrate superior olfactory abilities in women. Therefore, this study investigated the effects of an olfactory stimulus on subsequent sleep and assessed gender differences in such effects. Thirty-one young healthy sleepers (16 men and 15 women, aged 18 to 30 yr, mean+/-SD, 20.5+/-2.4 yr) completed 3 consecutive overnight sessions in a sleep laboratory: one adaptation, one stimulus, and one control night (the latter 2 nights in counterbalanced order). Subjects received an intermittent presentation (first 2 min of each 10 min interval) of an olfactory (lavender oil) or a control (distilled water) stimulus between 23:10 and 23:40 h. Standard polysomnographic sleep and self-rated sleepiness and mood data were collected. Lavender increased the percentage of deep or slow-wave sleep (SWS) in men and women. All subjects reported higher vigor the morning after lavender exposure, corroborating the restorative SWS increase. Lavender also increased stage 2 (light) sleep, and decreased rapid-eye movement (REM) sleep and the amount of time to reach wake after first falling asleep (wake after sleep onset latency) in women, with opposite effects in men. Thus, lavender serves as a mild sedative and has practical applications as a novel, nonphotic method for promoting deep sleep in young men and women and for producing gender-dependent sleep effects.

Biosynthesis and Therapeutic Properties ofLavandulaEssential Oil Constituents

“…It has been demonstrated that lavender aromatics can improve sleep in the elderly [12] and infants [13]. Furthermore, exposure to lavender odors during sleep results in increased duration of deep slow-wave stage sleep [14]. A therapeutic effect that is closely related to sleep is anxiety reduction, and many studies have evaluated the anxiolytic potential of lavender essential oil.…”

Affective semantic space of scents. Towards a universal scale to measure self-reported odor-related feelings

“…Numerous studies have shown that odors influence mood (Knasko 1992(Knasko , 1995Schiffman et al 1995a,b;Lehrner et al 2005), performance in cognitive tasks as well as person and object evaluation (Rotton 1983) congruently with their valence (see also Ehrlichman & Bastone 1992;Herz 2009). In addition, behavioral and physiological approaches revealed that odors can alter an individual's arousal by inducing relaxation or excitation (e.g., Torii et al 1988;Bensafi et al 2002a;Heuberger et al 2004;Goel et al 2005). Although sensory affect is increasingly included in sensory testing by the food and fragrance industry, and gains importance in product development, theoretical and methodological supports are only in the early stages of development.…”

The Effect of Inhalation Aromatherapy with Lavender on Sleep Quality of the Elderly in Nursing Care Homes: A Randomized Clinical Trial

“…It also helps to reduce insomnia, increase deep sleep with slow waves in people, and leaves one more alert during the day (13). The results of the Goel study showed that aromatherapy can improve sleep quality and its essence helps to fall asleep faster, increasing the 2nd stage of sleep, and decreased rapid eye movement (14).…”