The following post was written by Christopher Dillon Parker, a Junior Psychology Major at Wingate University, Wingate, NC.
Effective ways to maintain attention during sustained tasks have long been sought after by numerous individuals and corporations across the world. This is because everyone who must endure a tiring and tedious task needs an efficient way to make sure that they remain alert. A worker who cannot stay attentive and vigilant at their job can be a hazard to themselves and others around them, while a student who cannot remain focused on a test is less likely to do well or achieve their full potential. Not being able to focus well may also cause much undesired stress in these individuals. However, studies have shown that being able to remain alert during a long-lasting activity, while also keeping stress levels down, can be accommodated by something as simple as a smell.
A basis for these studies can be seen in a 1990s article, written by researchers at the University of Cincinnati, on the effects of smell on performance and stress during a long-lasting visual attention task. In the study these researchers conducted, they were testing to see whether or not certain smells had any effect on attention during a long task. They used thirty-six participants, 18 males and an equal amount of females, who were randomly assigned to one of three fragrance groups: a control group that received unscented air and two groups that either received Peppermint- (noted as being alerting) or Muguet-(noted as being relaxing) scented air (Warm, 1990). The subjects had to observe a dot centered vertically and horizontally between two parallel lines and were to complete the tasks of clicking the spacebar on the computer every time they thought the lines moved further apart. The subjects’ responses to movement of the lines were automatically counted as correct if they responded within 1.25 seconds of the lines having moved (Warm, 1990). Any other responses were counted as the subject having either failed to see when the lines moved or saying the lines moved when they had not. The subjects also wore a modified home oxygen mask throughout the experiment. This mask was used to deliver 30-second whiffs of either the unscented air or one of the scents to the subject after the first 4.5 minutes of the experiment and then every five minutes afterwards for forty minutes (Warm, 1990). They also measured the stress of the subjects by using three scales: the Thackray Mood Scales, the Yoshitake Symptoms of Fatigue Scale, and the Stanford Sleepiness Scale.
The overall findings of the study showed that the subjects who received scented air performed better on the vigilance task than those who were received unscented air. However, all of the subjects’ vigilance decreased over the course of the forty minutes. All subjects in scented conditions also felt less stressed than those in the unscented condition. Lastly, there were no differences in the ability to determine a signal from a non-signal between men and women in any of the three fragrance situations or during any particular time of day. The author (Joel Warm) of this article concluded that being given whiffs of air scented with either Peppermint or Muguet can increase one’s ability to detect signals during a long, vigilant task. Based off of his findings, Warm proposes that an exposure to fragrance (not necessarily just Peppermint or Muguet) may actually be effective in helping keep someone stimulated during long and demanding tasks (Warm, 1990).
Another experiment that validates this article is one concerning the effects of peppermint and cinnamon on driving alertness, mood, and workload. The authors of this study theorized that past experimentation on the effects of fragrances should allow them to conclude that being presented with certain odors while driving may create a more focused and alert driver, and may minimize any tiredness associated with driving for a prolonged period of time (Raudenbush, Grayhem, Sears & Wilson, 2009). They tested their hypothesis with a driving simulation test that was completed using virtual reality technology and the scented or unscented air was provided to the subject by way of a nasal cannula, which is a breathing tube with two small prongs that are inserted into the nostrils. Their subjects were tested in all three scent conditions, with 48 hour time intervals between each test to control for fatigue issues. The researchers found that the peppermint and cinnamon were successful in raising alertness, lowering fatigue and anxiety rates, and in reducing driver frustration during the driving tasks (Raudenbush, Grayhem, Sears & Wilson, 2009). Therefore, the drivers were found to be more alert, less anxious, and less fatigued. They also felt that the drive was much shorter than it really was in the fragrance situations. However, this study, unlike the first, tells of an instance where odor may not actually enhance performance. The authors explain that in one study, the presence of a lavender odor can significantly hinder the performance of working memory, the reaction time for any memory or attention oriented tasks, and mathematical reasoning (Ludvigson & Rottman, 1989; Moss, Cook, Wesnes & Dickett, 2003). Thus, it can be concluded that a pleasant odor’s presence alone does not always enhance performance. It would appear that it is a specific aspect of each distinct odor that causes one’s performance to be enhanced. However, some pleasant scents may actually be harmful to performance, such as in the experiment with the lavender. Therefore, any future research concerning the effects of smell on performance should pay close attention to what type of scent is given to their subjects to test.
The initial article for discussion made a very good hypothesis concerning the effects the fragrances were speculated to have on their subjects; however, neither fragrance ended up having any effect on performance efficiency. This just seems to draw a weaker conclusion since they were only testing the subjects’ ability to detect when two lines moved away from a dot. Their experiment could have been more strongly presented had they chosen to do a simulated driving scenario, like in the second experiment discussed. The could have also better presented their experiment if they had decided to administer a test, possibly similar to the SAT or any other standardized test. Had they performed an experiment more along these lines, they would have been able to validate their findings through a more real-world application. Overall, they had a good hypothesis, good methodology, and the conclusion that being exposed to a fragrance can increase alertness during a long and demanding task is difficult to dispute. The only truly negative aspect to their experiment is that they gave it no real-world application and they did not discuss the possibility that some fragrances could have a counteractive effect on performance efficiency.
Ludvigson, H. W. & Rottman, T. R. (1989). Effects of ambient odors of lavender and cloves on cognition, memory, affect and mood. Chemical Senses, 14, 525-536.
Moss, M., Cook, J., Wesnes, K. & Duckett, P. (2003). Aromas of rosemary and lavender essential oils differentially affect cognition and mood in healthy adults. International Journal of Neuroscience, 113, 15-38.
Raudenbush, B., Grayhem, R., Sears, T., & Wilson, I. (2009, June 01). FPO: IP research and communities. Retrieved from http://www.freepatentsonline.com/article/North-American Journal-Psychology/200919505.html
Warm, J. (1990). Effects of olfactory stimulation on performance and stress in a visual sustained attention task. Retrieved from http://journal.scconline.org/pdf/cc1991/cc042n03/p00199 p00210.pdf