Such compounds have

been detected in the blood of rodents exposed to the vapours of essentials oils. Jirovetz and colleagues demonstrated that serum levels of linalool and linalyl acetate in rats following lavender exposure were related to observed sedation [Jirovetz et al. 1990]. Kovar and colleagues assayed serum levels of Inhibitors,research,lifescience,medical 1,8-cineole, and recorded locomotor activity when rosemary oil was administered by inhalation or orally [Kovar et al. 1987]. The data showed that both the inhalation and oral administration of rosemary oil stimulated locomotor activity and that this was related to serum 1,8-cineole concentration. These findings cannot be explained by expectancy theory and suggest that more than simple stimulation of the olfactory organ is involved, with a direct pharmacological action on the central nervous system being implicated. In vitro neuropharmacological Inhibitors,research,lifescience,medical research has also provided some interesting data that are pertinent here. Orhan

and colleagues reported that extracts of rosemary displayed PLX4032 nmr significant inhibitory effects on both acetylcholinesterase (AChE) and butyrylcholinesterase enzymes [Orhan et al. 2008]. The authors go on to identify that the major active component of the essential oil is 1,8-cineole, a terpene Inhibitors,research,lifescience,medical that has previously been identified as possessing anti- AChE activity [Perry et al. 2000, 2003; Savelev et al. 2003]. Such activity is suggestive of potential cognitive impact and indeed underpins the pharmacological activity of a number of dementia treatments [Orhan et al. 2008]. However, it should be stressed that any activity might be a consequence of the synergistic Inhibitors,research,lifescience,medical combinations

of components present rather than a single compound. The possibility of such a pharmacological mechanism Inhibitors,research,lifescience,medical for rosemary aroma would provide supporting evidence to the concept that each individual aroma of an essential oil has its own unique pattern of influence on both cognition and mood as a result of the unique composition of volatile aromatic compounds. To investigate this further, the current study assayed PDK4 serum for 1,8-cineole and correlated this with cognitive performance under conditions of rosemary aroma exposure. Method Design The study used a correlational design to investigate a possible relationship between the plasma 1,8-cineole levels and cognitive performance and mood. Treatment was by way of exposure to the aroma of rosemary essential oil. Participants were randomly assigned to be exposed to the aroma in the cubicle for 4, 6, 8 or 10 min prior to completing the cognitive tests. This period was not kept constant so as to facilitate a range of levels of absorption of compounds to take place across the participant group.