Examining the differential effects of natural and synthetic aromas of lavender and peppermint on cognition, mood, and subjective workload

There is reliable, empirical evidence that various inhaled aromas can significantly affect mood, cognition, physiology and behavior (Herz, 2009). However, the literature often does not document whether natural or synthetic fragrances were used when evaluating these factors. Also, no studies to date have compared natural and synthetic versions of the same odors. The current study attempted to determine whether the natural aromas of lavender and peppermint were superior to their synthetic counterparts in terms of measurable differences in cognition, mood, and subjective workload among 180 college students. Specific Aim 1 compared the inhalation of natural fragrances to the inhalation of synthetic fragrances on measures of cognitive function. Specific Aim 2 addressed whether the inhalation of natural fragrances, as opposed to synthetic fragrances, was associated with greater group differences on a measure of self-reported mood. Finally, Specific Aim 3 compared the inhalation of natural fragrances to synthetic fragrances with respect to their ability to decrease subjective workload and increase subjective performance. This Aim also assessed whether subjective workload was a mediator of cognition and mood. The initial results from this study reinforced the assertion that fragrances are capable of altering cognition, with further evidence revealing that the natural aroma of peppermint is superior to its synthetic counterpart in bringing about these changes. However, after performing a statistical correction for conducting multiple comparisons, these results largely do not remain significant. Combined with small effect sizes, this study was unable to provide conclusive evidence to support the statement that natural aromas are superior to their synthetic counterparts in terms of their ability to alter cognition, mood, and subjective workload.