Influence of emotional state on cognitive performance following odor stimulus presentation

We examined the effects of pleasant and unpleasant emotions induced by olfactory stimulation on cognitive function in 14 young women (21.7±0.2 yrs.). They were exposed to odors (Rose, Caramel, Isovaleric acid, Peach, Skatole or Odorless paraffine) that elicited pleasant, unpleasant or neutral emotions followed by the Stroop color-word test (SCWT) for cognitive assessment. Odor concentration was set to the lowest level at which subjects could recognize odor’s definite character. Emotional changes to each odor stimulus were subjectively evaluated with 11 grades. The subjective rating against the Iso valeric acid and Scatole revealed a clear unpleasant feeling in all subjects. Peach, Caramel, and Rose elicited either “pleasant” or “unpleasant” emotions induced, indicating individual differences in the pleasant and unpleasant feelings elicited by olfactory stimulation. Unpleasant odor stimulus（Isovaleric acid and Skatole）, significantly lengthened the total SCWT time, whereas Odorless paraffine did not. A significant negative correlation was found between emotional score for odors (Isovaleric acid and Caramel) and the total SCWT time. These results suggest that the elicitation of unpleasant emotions decreases cognitive performance in young women.