With rush hour traffic jams, endless roadworks, tailgaters and the rest it can sometimes be hard to keep your emotions in check when behind the wheel. But what if there was something that could give your mind a helping hand when driving? Studies have shown that smell can change your mood, and not just to make you hungry. In fact, certain aromas could improve alertness or relax people, for example.

We thought it was time to harness the pungent powers of herbs, spices and other fragrant materials to try and help motorists stay level headed on the road. So after surveying Britain's drivers to find out the most often-experienced negative emotions, we set about creating five concoctions, with the expert knowledge of Professor Charles Spence.

 

Want the chance to win one of our fragrant fresheners? Simply enter the competition below!

 

One whiff to settle road rage?

Prof. Charles Spence (Charles.spence@psy.ox.ac.uk)

What we smell has a far larger impact on our behaviour than any one of us would expect, and our driving behaviour is no exception in this regard.1 In fact, a growing body of scientifically credible research now shows that releasing a pleasant scent while driving can be used to do everything from calm aggressive drivers, through to masking the malodourous smells that typically signal air pollution, and from helping drivers not to fall asleep at the wheel, through to making the driving experience more multisensorially immersive.2 (The one thing that ambient scent can’t be used to do, though, is to deliver time critical information as, in humans, the sense of smell is one of the slowest senses to respond to ambient stimulation.3)

There can be no doubting that the last few years have seen growing interest in the intelligent use of ambient olfactory cues while driving.4 Indeed, a number of car companies have already been considering the use of releasing different scents inside the car to either match or modulate the driver’s mood, or else to complement the scenery, and hence provide a more enjoyable multisensory driving experience.5 For instance, back in 2014, Mercedes was one of the first car companies to introduce an olfactory display (called “active perfuming system”) into certain of their models.6

 

 

Below, I make a number of recommendations (based on the emerging science) in terms of the most appropriate scents to enhance various aspects of the experience when driving:

1) Releasing an alerting scent: According to the Automobile Association of Great Britain, at least 10% of all road fatalities are attributable to drivers falling asleep while at the wheel. Elsewhere, Andrew Parks, of the Driving Simulation Center at Britain’s Transport Research Laboratory, has estimated that as many as a third of all road traffic accidents may be attributable to the behaviour of drowsy drivers!7 Consequently, it should come as little surprise to find that many human factors researchers have, in recent years, become increasingly interested in the possibility of using the automated presentation of in-car scent to try to reduce sleep-related accidents. The idea here is that the release of an alerting scent such as, for example, pink grapefruit or peppermint should help promote alertness.8

Meanwhile, in terms of the relevant background research, it is worth noting that, back in 2011, a group of Japanese researchers also developed a system to fight drowsiness while driving.9 They demonstrated that releasing specific smells (peppermint, rosemary, eucalyptus, and lemon) successfully extended the period of a driver’s wakefulness. Elsewhere, Raudenbush et al. demonstrated enhanced driver alertness and attentiveness following the release of peppermint and cinnamon scent.10 Intriguingly, while both scents reduced frustration and helped participants to focus their attention on the driving task, peppermint also resulted in faster reactions from the drivers as well. And finally here, Martin and Cooper reported that releasing the scent of lemon had a positive impact on people’s braking performance in a simulated driving task.11

Whilst it is obviously a very bad idea to drive if you are too tired, the hope amongst many in the research community is that the release of a sudden burst of an alerting scent may help prevent the drowsy driver from falling asleep long enough for them to be able to pull-over safely and take a proper break. It is also worth bearing in mind here that alerting scents also have the advantage that they aren’t as unpleasant as loud alerting sounds, say.

 

 

2) Releasing a relaxing scent: Just imagine that your car were to release a relaxing scent, something like lavender, whenever it detects that you are becoming stressed (e.g., because you have started gripping the steering wheel more tightly than usual, or are braking sharply). Interestingly, the scent of lavender has been shown to aid relaxation across a range of situations and across many different age groups.12 Intriguingly, a prototype system, called the Digiscent-Operated Persuasive Environment (or DOPE for short), was already being developed at the end of the last century. The idea was that it could present a whiff of a relaxing scent at just those times when the driver shows signs of aggressive or erratic behaviour at the wheel.13 DOPE was a computer controlled system that could release ambient odours in response to various signals received from a series of sensors placed on the steering wheel, and embedded in the driver’s seat. Whenever the sensors indicated, for example, that a driver was gripping the steering wheel too tightly, the system would release a burst of pleasant fragrance to help the driver calm down. Similarly, the idea was that if the system detected that a driver’s braking was becoming too agressive, DOPE might give out a whiff of burnt rubber instead! Unfortunately, however, the company behind DOPE – Digiscents – went belly-up soon afterwards.14

3) Releasing a mood enhancing scent Masking scent to help reduce aggression: Who knows, releasing pleasant scents may even help as far as reducing the incidence of road rage is concerned too.15 In fact, in some of the earliest research in this area, Baron and Kalsher demonstrated that releasing the scent of lemon improved both the alertness and, more importantly, the mood of the driver.16

 

 

4) Releasing a scene-congruent scent: The idea here is to choose a scent that help matches the environment in which the driver is passing through. Just think about how it would feel to smell the scent of pine needles while driving through the forest, say, or the smell of fresh cut grass (geosmin) while driving through the fields. The evidence from a number of studies now shows that congruent scents can be used to enhance the sense of immersion across a range of different situations/environments.17

5) Releasing scents to reduce the symptoms of travel sickness: One other potential use of ambient scent is in helping deal with the symptoms of travel sickness. Suggestions here include everything from the scent of ginger through to, once again, the scent of peppermint.18

6) Releasing personal scents: One other idea to think about here is scent messaging.19 Imagine getting a whiff of your partner’s perfume or aftershave should they call while you are on the road. This kind of personalised scenting would obviously be individual to each driver.

 

The air fresheners are a promotional product only and should not be used for the purpose of curing or relieving certain emotions while driving.

 

References

1 Mustafa, M., Rustama, N., & Siran, R. (2016). The impact of vehicle fragrance on driving performance: What do we know? Procedia - Social and Behavioral Sciences, 222, 807-815; Spence, C. (2002). The ICI report on the secret of the senses. London, UK: The Communication Group.

2 Bounds, W. (1996). Sounds and scents to jolt drowsy drivers. Wall Street Journal, May 6th, B1, B5.

3 Ho, C., & Spence, C. (2008). The multisensory driver: Implications for ergonomic car interface design. Aldershot: Ashgate Publishing; Spence, C., & Squire, S. B. (2003). Multisensory integration: Maintaining the perception of synchrony. Current Biology, 13, R519-R521.

4 Bordegoni, M., Carulli, M., & Shi, Y. (2016). Investigating the use of smell in vehicle-driver interaction. ASME 2016 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. Volume 1A: 36th Computers and Information in Engineering Conference. Charlotte, North Carolina, August 21-24th. Paper No. DETC2016-60541, pp. V01AT02A053; 10 pages; Dmitrenko, D., Vi, C. T., & Obrist, M. (2016). A comparison of scent-delivery devices and their meaningful use for in-car olfactory interaction. In Proceedings of the 8th International Conference on Automotive User Interfaces and Interactive Vehicular Applications (Automotive'UI 16) (pp. 23-26). ACM, New York, NY.

5 E.g., see Ho, C., & Spence, C. (2013). Affective multisensory driver interface design. International Journal of Vehicle Noise and Vibration (Special Issue on Human Emotional Responses to Sound and Vibration in Automobiles), 9, 61-74. doi: 10.1504/IJVNV.2013.053817.

6 See Clark, J. (2013, March 26). 2014 Mercedes-Benz S-Class interior is “the essence of luxury”. http://www.emercedesbenz.com/autos/mercedes-benz/s-class/2014-mercedes-benz-s-class-interior-is-the-essence-of-luxury/.

7 Graham-Rowe, D. (2001). Asleep at the wheel. New Scientist, 169 (2283), 24; Sample, I. (2001). You drive me crazy. New Scientist, 171 (2300), 24; See also Mitler, M., et al. (1988). Catastrophes, sleep, and public policy. Sleep, 11, 100.

8 Ho, C., & Spence, C. (2005). Olfactory facilitation of dual-task performance. Neuroscience Letters, 389, 35-40; Warm, J. S., Dember, W. N., & Parasuraman, R. (1991). Effects of olfactory stimulation on performance and stress in a visual sustained attention task. Journal of the Society of Cosmetic Chemists, 42, 199-210; See also Gould, A., & Martin, G. N. (2001). A good odour to breathe? The effect of pleasant ambient odour on human visual vigilance. Applied Cognitive Psychology, 15, 225-232; Furuhata, T., Miyachi, T., & Adachi, T. (2011). Driving prevention system by gradual increase low frequency stimulation and high density oxygen with the fragrance of GF (Grape Fruits). In A. König et al. (Eds.): KES 2011, Part III, LNAI 6883, pp. 11-20, Berlin Heidelberg: Springer-Verlag.

9 Yoshida, M., Kato, C., Kakamu, Y., Kawasumi, M., Yamasaki, H., Yamamoto, S., et al. (2011). Study on stimulation effects for driver based on fragrance presentation. IAPR Conference on Machine Vision Applications, 9-26.

10 Raudenbush, B., Grayhem, R., Sears, T., & Wilson, I. (2009). Effects of peppermint and cinnamon odor administration on simulated driving alertness, mood and workload. North American Journal of Psychology, 11, 245-256.

11 Martin, G. N., & Cooper, J. A. (2007). Adding zest to difficult journeys: Odour effects on simulated driving performance. Paper presented at the BPS Annual Conference. And while it may not be appealing to most, chewing dried squid is apparently also very effective at keeping drivers awake!: see Fruhata, T., Miyachi, T., Adachi, T., Iga, S., & Davaa, T. (2013). Doze sleepy driving prevention system (Finger massage, high density oxygen spray, grapefruit fragrance) with that involves chewing dried shredded squid. Procedia Computer Science, 22, 790-799.

12 Spence, C. (2003). A new multisensory approach to health and well-being. In Essence, 2, 16-22.

13 Harris, E., Sengupta, C., & Gray, A. (2000). DOPE: The Digiscent-operated persuasive environment. (http://www.stanford.edu/~demian23/captology/DOPE/); Cf. Schiffman, S. S., & Siebert, J. M. (1991). New frontiers in fragrance use. Cosmetics and Toiletries, 106, 39-45.

14 Platt, C. (1999). You’ve got smell. Wired, November 1st. https://www.wired.com/1999/11/digiscent/; Dusi, A. (2014). What does $20 million burning smell like? Just ask DigiScents! StartupOver, January 19th. http://www.startupover.com/en/20-million-burning-smell-like-just-ask-digiscents/.

15 Fumento, M. (1998). “Road rage” versus reality. Atlantic Monthly, 282 (2), 12-17. https://www.theatlantic.com/magazine/archive/1998/08/road-rage-versus-reality/377156/. James, L., & Nahl, D. (2000). Road rage. Amherst, NY: Prometheus Books.

16 Baron, R. A., & Kalsher, M. J. (1998). Effects of a pleasant ambient fragrance on simulated driving performance: The sweet smell of... safety? Environment and Behavior, 30, 535-552.

17 Spence, C., Obrist, M., & Ranasinghe, N. (submitted). Digitizing the chemical senses: Possibilities & pitfalls. International Journal of Human-Computer Studies.

19 Bodnar, A., Corbett, R., & Nekrasovski, D. (2004). AROMA: Ambient awareness through olfaction in a messaging application. Proceedings of the 6th International Conference on Multimodal Interfaces, 183-190.