Could Rosemary Scent Boost Brain Performance?

Hailed since ancient times for its medicinal properties, we still have a lot to learn about the effects of rosemary. Now researchers writing in Therapeutic Advances in Psychopharmacology, published by SAGE, have shown for the first time that blood levels of a rosemary oil component correlate with improved cognitive performance.

Rosemary (Rosmarinus officinalis) is one of many traditional medicinal plants that yield essential oils. But exactly how such plants affect human behaviour is still unclear. Mark Moss and Lorraine Oliver, working at the Brain, Performance and Nutrition Research Centre at Northumbria University, UK designed an experiment to investigate the pharmacology of 1,8-cineole (1,3,3-trimethyl-2-oxabicyclo[2,2,2]octane), one of rosemary's main chemical components.

The investigators tested cognitive performance and mood in a cohort of 20 subjects, who were exposed to varying levels of the rosemary aroma. Using blood samples to detect the amount of 1,8-cineole participants had absorbed, the researchers applied speed and accuracy tests, and mood assessments, to judge the rosemary oil's affects.

Results indicate for the first time in human subjects that concentration of 1,8-cineole in the blood is related to an individual's cognitive performance – with higher concentrations resulting in improved performance. Both speed and accuracy were improved, suggesting that the relationship is not describing a speed–accuracy trade off. Meanwhile, although less pronounced, the chemical also had an effect on mood. However, this was a negative correlation between changes in contentment levels and blood levels of 1,8-cineole, which is particularly interesting because it suggests that compounds given off by the rosemary essential oil affect subjective state and cognitive performance through different neurochemical pathways. The oil did not appear to improve attention or alertness, however.

Plasma 1,8-cineole correlates with cognitive performance following exposure to rosemary essential oil aroma by Mark Moss and Lorraine Oliver was published February 24, 2012 in Therapeutic Advances in Psychopharmacology.

For a copy of the article please contact: ashley.loar@sagepub.com