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TopEffect Of Olfactory Factors In General
The Smell Report (2002) provides some ideas about emotions elicited by odors. There is convincing evidence that the perception of smell in general consists not only of the sensation of the odor itself but also of the experiences and emotions which evoke these sensations. Smells can elicit strong emotional reactions. In some studies on reactions to odors, responses show that many of our olfactory preferences are based on emotional associations and connected memories.
The olfactory receptors are directly connected to the limbic system, the oldest part of the brain, the seat of emotions. Smell sensations are relayed to the cortex, where cognitive recognition occurs, only after the deepest parts of our brains have been stimulated in some way. It is therefore extremely interesting to find out whether cognitive activities for solving specific problems are intensified by odors. When a particular scent is named, for example, vanilla or peppermint, the scent has already activated the limbic system, triggering even more deep-seated emotional responses. However, in contrast to these studies we did not inform our participants of the experiment about the scented room they would have to work in.
Further on, there is lots of research on mood-effects. It is meanwhile well-known that pleasant fragrances can improve our mood and sense of well-being. Recent studies have shown that our expectations about an odor, rather than any direct effects of exposure to it may sometimes be responsible for the mood and health benefits reported. There is obviously also the possibility for placebo effects, just telling subjects that a pleasant or unpleasant odor was being administered, which they might not be able to smell, as shown in various self-reports of mood and well-being.
In our study we are able to demonstrate that subjects do respond to some extent to fragrances by behaving in a different way than the subjects working in odorless rooms. There has not been ever any similar study in this direction: We plan to demonstrate that the smell of peppermint improves the overall mood considerably when solving a given task.
Pleasant fragrances have been found to encourage action and to have a positive effect on mood across all age groups. In experiments involving stimulation of the left and right nostrils with pleasant and unpleasant fragrances, researchers have found differences in olfactory cortical neuron activity in the left and right hemispheres of the brain which correlate with the ‘pleasantness ratings’ of the odorants. These studies are taken to indicate that positive emotions are predominantly processed by the left hemisphere of the brain, while negative emotions are more often processed by the right hemisphere.
The positive emotional effects of pleasant fragrances also affect our perceptions of other people. In experiments, subjects exposed to pleasant fragrances tend to give higher ‘attractiveness ratings’ to people in photographs, although some recent studies have shown that these effects are only significant where there is some ambiguity in the pictures. To put it concisely, if a person is clearly very attractive or very unattractive, fragrance does not affect our judgment. But if the person neither particularly attractive nor unattractive, a pleasant fragrance can tip the balance of our evaluation in his or her favor.
Smith A. (2008) reports in her paper The Olfactory Process and its Effect on Human Behavior that the sense of smell – olfaction - has a powerful command over much of our behavior, including memory. Intrigued with this connection as an example of sensory input influencing behavior, it is still a goal to examine the neurobiology of the olfaction process in humans and to investigate the ways in which odors elicit particular behaviors.
For humans, olfaction is a primitive sense, whereas other mammals, birds and insects rely predominately on their sense of smell for survival. Although smell seems far less meaningful to humans, there is an important link between olfaction and behavior.
The effect of peppermint on cognitive functioning has been discussed at length in a study by Raudenbush B. (Wheeling Jesuiut University, Dept of Psychology – Sense of Smell Institute) in a paper (2004) where it is pointed out that the peppermint plant contains over 40 distinct chemical compounds. Applying the essential oils of peppermint has been touted as a stimulant in various cases. The study examines the effects of peppermint on mental performance and cognitive functioning.