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Direct application of specially formulated scent compositions (AromaStick®) prolongs attention and enhances visual scanning speed

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Abstract

Recently, a series of experiments demonstrated that direct stimulation of the olfactory system by means of an odor inhaler targets brain areas associated with stress reduction and pain relief. This paper follows up on these findings and investigates whether such effects can also be found for inhalers specially designed to increase attention and concentration. In a three-armed, randomized, controlled experiment participants' cognitive ability to discriminate between similar visual stimuli was tested either with or without the use of an odor inhaler. Concentration, visual scanning speed, and accuracy were assessed to gauge differential effects. Both odor inhalers outperformed the control condition where no odor was used. The effects were large and showed in all parameters. The direct application of specially designed essential oil compositions enhances attention and concentration when used during short-term breaks in a stressful and attention-demanding cognitive task.

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... In another experiment, two inhalers improved concentration and visual scanning speed in a taxing discrimination task by more than 20 per cent. These effects lasted for at least 15 minutes and did not deteriorate [17]. ...
... To assess statistical effects as well as their clinical/practical relevance effect sizes and confidence intervals rather than significance tests were calculated. This was in alignment with meta-analytical practice [24], the statistics applied in the first series of studies testing odor inhalers [16,17], and as a consequence of the highly problematic use of NHST 2 . Specifically, to determine treatment effects within groups (i.e. ...
Article
Background: Recently, it was demonstrated in a series of experiments that a specifically designed odor inhaler outperformed well-known and popular stress relieving techniques. In another experiment it was shown that odor inhalers increased attention and concentration in a demanding cognitive task. Aims: This paper follows up on these experiments and investigates whether such effects can also be found for an inhaler specially designed to reduce pain. Methods: Two prospective cross-over documentary studies were conducted comparing participants’ individual pain management (menstrual pain and chronic lower back pain) with an odor inhaler used as an adjuvant. Results: The odor inhaler improved pain dynamics like onset of pain and pain duration for both menstrual pain and lower back pain in a natural setting. In individuals suffering from chronic lower back pain, the inhaler also increased the pain alleviating effect of the individual pain management method. In both studies mood and well-being were considerably increased when the inhaler was applied. No side effects were reported. Conclusions: Even highly effective individual pain-relieving methods benefit from the use of this odor inhaler by changing pain dynamics and improving pain relief. Therefore, it is a practically relevant, side effect free, and ready-to-use tool for pain management, especially when used as an adjuvant.
... Not only did they outperform established relaxation interventions such as progressive muscle relaxation, but the large effects also showed in various cardiovascular and hormonal parameters. Depending on the odor composition used, such inhalers were also able to produce analgesic effects in individuals suffering from chronic and recurring pain [16], and to improve concentration and visual scanning speed in a taxing discrimination task [17]. Some of these effects were very fast acting (with a latency of only a few seconds to minutes depending on the target system) and occurred after only a few inhalations. ...
... Effect sizes rather than significance tests were calculated. This was in alignment with meta-analytical practice [22], the statistics applied in the first series of studies testing odor inhalers [15][16][17], and as a consequence of the highly problematic use of NHST (null hypothesis significance testing) 2 . Specifically, to determine within treatment effects the effect size Cohen's [35] and confidence intervals (95%) were calculated [36]: ...
Article
Background: A number of recent studies have shown that a specifically designed odor inhaler containing various scent compositions has the ability to decrease blood pressure, heart rate, and cortisol levels. Similar results were found for the reduction of chronic pain or the enhancement of selective attention and concentration. Objective: This paper follows up on these findings and investigates whether a specially designed inhaler (‘Energy’) is capable of temporarily increasing blood oxygenation. Method: A prospective, controlled experimental study involving standardized breathing cycles was run to compare normal, deep breathing with breathing through an odor inhaler. Results: The difference of blood oxygenation between normal breathing and odor inhalation was very large (d = 2). It lasted three times longer than that of normal breathing. The effect showed in all individuals and did not abate after repeated use. Conclusion: Blood oxygenation can be increased over and above the effect of deep breathing when using this odor inhaler.
... Not only did they outperform established relaxation interventions such as progressive muscle relaxation, but the large effects also showed in various cardiovascular and hormonal parameters. Depending on the odor composition used, such inhalers were also able to produce analgesic effects in individuals suffering from chronic and recurring pain [16], and to improve concentration and visual scanning speed in a taxing discrimination task [17]. Some of these effects were very fast acting (with a latency of only a few seconds to minutes depending on the target system) and occurred after only a few inhalations. ...
... Effect sizes rather than significance tests were calculated. This was in alignment with meta-analytical practice [22], the statistics applied in the first series of studies testing odor inhalers [15][16][17], and as a consequence of the highly problematic use of NHST (null hypothesis significance testing) 2 . Specifically, to determine within treatment effects the effect size Cohen's [35] and confidence intervals (95%) were calculated [36]: ...
Article
Background: A number of recent studies have shown that a specifically designed odor inhaler containing various scent compositions has the ability to decrease blood pressure, heart rate, and cortisol levels. Similar results were found for the reduction of chronic pain or the enhancement of selective attention and concentration. Objective: This paper follows up on these findings and investigates whether a specially designed inhaler (‘Energy’) is capable of temporarily increasing blood oxygenation. Method: A prospective, controlled experimental study involving standardized breathing cycles was run to compare normal, deep breathing with breathing through an odor inhaler. Results: The difference in blood oxygenation between normal breathing and odor inhalation was very large (d = 2). It lasted three times longer than that of normal breathing. The effect was shown in all individuals and did not abate after repeated use. Conclusion: Blood oxygenation can be increased over and above the effect of deep breathing when using this odor inhaler.
... In another experiment, two inhalers improved concentration and visual scanning speed in a taxing discrimination task by more than 20 per cent. These effects lasted for at least 15 minutes and did not deteriorate [17]. ...
... To assess statistical effects as well as their clinical/practical relevance effect sizes and confidence intervals rather than significance tests were calculated. This was in alignment with meta-analytical practice [24], the statistics applied in the first series of studies testing odor inhalers [16,17], and as a consequence of the highly problematic use of NHST 2 . Specifically, to determine treatment effects within groups (i.e. ...
Article
Background: Recently, it was demonstrated in a series of experiments that a specifically designed odor inhaler outperformed well-known and popular stress relieving techniques. In another study it was shown that odor inhalers increased attention and concentration in a demanding cognitive task. Objective: This paper follows up on these experiments and investigates whether such effects can also be found for an inhaler specially designed to reduce pain. Method: Two prospective randomized, controlled cross-over documentary studies were conducted comparing participants’ individual pain management (menstrual pain and chronic lower back pain) with an odor inhaler used as an adjuvant. Results: The odor inhaler improved pain dynamics like onset of pain and pain duration for both menstrual pain and lower back pain in a natural setting. In individuals suffering from chronic lower back pain, the inhaler also increased the pain alleviating effect of the individual pain management method. In both studies mood and well-being were considerably increased when the inhaler was applied. No side effects were reported. Conclusions: Even highly effective individual pain-relieving methods benefit from the use of this odor inhaler by changing pain dynamics and improving pain relief. Therefore, it helps to facilitate and amplify pain management.
... Schneider (Schneider 2016) explored the effects of two EO mixtures on selective attention. ...
Chapter
The use of essential oils to control arousal and cognitive performance has a long tradition in mankind. In our time, the demand for remedies promising fast but safe recovery from mental stress is ever-growing. Thus, today a plethora of popular aromatherapy guidebooks exists, offering advice on the use of essential oils for a multitude of health complaints. With some delay, scientists have started to substantiate the claims raised in the popular literature and verify the effects of essential oils on cognitive functioning and performance. This chapter aims to give an overview about the available scientific literature dealing with the influence of essential oils and fragrances on arousal and cognitive performance. The topics covered in this chapter will range from brain potentials related to arousal over alertness and attention to learning and memory. In addition, it will be discussed whether olfactory versus non-olfactory administration influences the effects of essential oils on cognitive functions and how psychological phenomena, such as hedonic preferences, semantic associations, and individual expectations may shape these effects.
... Moss et al., 2003Moss et al., , 2008. Similarly, direct application of essential oil scents to the nose can increase the ability to discriminate between similar visual stimuli in a stressful setting (Schneider, 2016). Large improvements in these abilities of up to 30 percent occurred during shortterm breaks with only a few deep inhalations. ...
Article
Two recent publications demonstrated that specifically designed essential odor inhalers can enhance performance through (a) better selective attention and scanning speed and (b) physiological changes of increased heart rate variability and blood oxygenation. In this study, we compared two natural odor inhalers with a popular energy drink (Red Bull®) with regard to their ability to improve vigilance on a computerized attention test. We employed a four-armed, randomized controlled experimental design and used a modified version of the CompACT-Vi test module to investigate whether deep inhalations of essential oil scents improved vigilance. Both inhalers markedly improved the number of correctly identified targets and participants’ reaction time when compared to a control condition and consumption of Red Bull® (0.9 < d < 1.3). Additionally, the number of correctly solved mathematical sums during the second half of the vigilance test was substantially higher (d = 1.3) with the use of inhalers than for the control and Red Bull® participants. Inhaler use was also associated with relatively increased heart rate variability (d = 1.0) as a mechanism of adapting to the experimental demands. Thus, short and deep inhalations of essential oil scents delivered directly to the nose improved vigilance, while a popular energy drink failed to show an effect beyond that of a control group receiving no stimulant.
... Recently, an alternative inhaler (AromaStick ® ) was designed which directly delivers volatile phytochemicals to the nose. It contains essential oil compositions whose principal and individual effects are well documented [21][22][23][24]. Depending on the odor composition used, the inhaler produces various clinically relevant effects. ...
Article
Background: There are effective pharmaceutical agents to treat seasonal allergic rhinitis, but more and more individuals resort to alternative forms of treatment. One possible alternative candidate is essential oils. Recently, an inhaler specifically designed to deliver essential oil scents has proven very effective in treating various medical parameters (e.g., blood pressure, heart rate, cortisol, blood oxygenation, or pain). Objective: This work investigates whether an inhaler (AromaStick® ‘Nasal Fresh’) designed to clear the nasal passageway and reduce congestion has beneficial effects in individuals suffering from seasonal allergic rhinitis. Method: A two-armed, randomized, controlled, double-blind effectiveness trial involving individuals with medium to strong symptoms was conducted to investigate the inhaler’s specific treatment effects. Results: Over a period of two weeks, the odor inhaler strongly reduced allergic symptoms for both overall AR symptomatology (d = 1.2) and individual symptomatic allergic rhinitis burden (d = 1.7). Conclusion: The inhaler produced strong symptom relief. Effects were largest in individuals suffering primarily from nasal symptoms.
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Background: Recently, it was demonstrated in a series of experiments that a specifically designed odor inhaler outperformed well-known and popular stress relieving techniques. In another experiment it was shown that odor inhalers increased attention and concentration in a demanding cognitive task. Aims: This paper follows up on these experiments and investigates whether such effects can also be found for an inhaler specially designed to reduce pain. Methods: Two prospective cross-over documentary studies were conducted comparing participants’ individual pain management (menstrual pain and chronic lower back pain) with an odor inhaler used as an adjuvant. Results: The odor inhaler improved pain dynamics like onset of pain and pain duration for both menstrual pain and lower back pain in a natural setting. In individuals suffering from chronic lower back pain, the inhaler also increased the pain alleviating effect of the individual pain management method. In both studies mood and well-being were considerably increased when the inhaler was applied. No side effects were reported. Conclusions: Even highly effective individual pain-relieving methods benefit from the use of this odor inhaler by changing pain dynamics and improving pain relief. Therefore, it is a practically relevant, side effect free, and ready-to-use tool for pain management, especially when used as an adjuvant.
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IntroductionIndividual studiesThe summary effectHeterogeneity of effect sizesSummary points
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The second edition of this book is virtually a new book. It is the only comprehensive text on the safety of essential oils, the first review of essential oil/drug interactions, and it provides detailed essential oil constituent data not found in any other text. Much of the existing text has been re-written, and 80% of the text is completely new. There are 400 comprehensive essential oil profiles and almost 4000 references. There are new chapters on the respiratory system, the cardiovascular system, the urinary system, the digestive system and the nervous system. For each essential oil there is a full breakdown of constituents, and a clear categorization of hazards and risks, with recommended maximum doses and concentrations. There are also 206 Constituent Profiles. There is considerable discussion of carcinogens, the human relevance of some of the animal data, the validity of treating an essential oil as if it was a single chemical, and the arbitrary nature of uncertainty factors. There is a critique of current regulations.
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Statistical rituals largely eliminate statistical thinking in the social sciences. Rituals are indispensable for identification with social groups, but they should be the subject rather than the procedure of science. What I call the “null ritual” consists of three steps: (1) set up a statistical null hypothesis, but do not specify your own hypothesis nor any alternative hypothesis, (2) use the 5% significance level for rejecting the null and accepting your hypothesis, and (3) always perform this procedure. I report evidence of the resulting collective confusion and fears about sanctions on the part of students and teachers, researchers and editors, as well as textbook writers.
Article
This study reports the results of a large scale literature review of research studying the relationship between intelligence and speed of information-processing. Data from 172 studies, with a total of 53,542 participants, were analyzed to find the mean correlations between a variety of intelligence and mental speed measures. Additionally, effect sizes representing group differences on speeded measures were calculated, and multivariate behavioral genetic (BG) studies reporting genetic correlations between speed of processing and IQ were reviewed. The results indicate that measures of intelligence are significantly correlated with mental speed and that for some measures this relationship shows a trend toward strengthening as the complexity of the speeded tasks increase. Additionally, there are various group differences on mental speed tasks: females and males are quicker than one another on different speeded tasks, and younger adults have shorter (faster) reaction time latencies than older adults and children. Reports comparing whites and blacks on mental speed yield inconsistent results. Finally, BG studies indicate that phenotypic correlations between IQ and mental speed are substantially attributable to correlated genetic factors.
Article
Remarkable advances in our understanding of olfactory perception have been made in recent years, including the discovery of new mechanisms of olfactory signaling and new principles of olfactory processing. Here, we discuss the insight that has been gained into the receptors, cells, and circuits that underlie the sense of smell.
Article
MOST THEORIES IN THE AREAS OF PERSONALITY, CLINICAL, AND SOCIAL PSYCHOLOGY PREDICT ONLY THE DIRECTION OF A CORRELATION, GROUP DIFFERENCE, OR TREATMENT EFFECT. SINCE THE NULL HYPOTHESIS IS NEVER STRICTLY TRUE, SUCH PREDICTIONS HAVE ABOUT A 50-50 CHANCE OF BEING CONFIRMED BY EXPERIMENT WHEN THE THEORY IN QUESTION IS FALSE, SINCE THE STATISTICAL SIGNIFICANCE OF THE RESULT IS A FUNCTION OF THE SAMPLE SIZE. CONFIRMATION OF 1 DIRECTIONAL PREDICTION GENERALLY BUILDS LITTLE CONFIDENCE IN THE THEORY BEING TESTED. MOST THEORIES SHOULD BE TESTED BY MULTIPLE CORROBORATION AND MOST EMPIRICAL GENERALIZATIONS BY CONSTRUCTIVE REPLICATION. STATISTICAL SIGNIFICANCE, PERHAPS THE LEAST IMPORTANT ATTRIBUTE OF A GOOD EXPERIMENT, IS NEVER A SUFFICIENT CONDITION FOR CLAIMING THAT (1) A THEORY HAS BEEN USEFULLY CORROBORATED, (2) A MEANINGFUL EMPIRICAL FACT HAS BEEN ESTABLISHED, OR (3) AN EXPERIMENTAL REPORT OUGHT TO BE PUBLISHED.
Article
The test of significance does not provide the information concerning psychological phenomena characteristically attributed to it; and a great deal of mischief has been associated with its use. The basic logic associated with the test of significance is reviewed. The null hypothesis is characteristically false under any circumstances. Publication practices foster the reporting of small effects in populations. Psychologists have "adjusted" by misinterpretation, taking the p value as a "measure," assuming that the test of significance provides automaticity of inference, and confusing the aggregate with the general. The difficulties are illuminated by bringing to bear the contributions from the decision-theory school on the Fisher approach. The Bayesian approach is suggested.
Article
EEG activity, alertness, and mood were assessed in 40 adults given 3 minutes of aromatherapy using two aromas, lavender (considered a relaxing odor) or rosemary (considered a stimulating odor). Participants were also given simple math computations before and after the therapy. The lavender group showed increased beta power, suggesting increased drowsiness, they had less depressed mood (POMS) and reported feeling more relaxed and performed the math computations faster and more accurately following aromatherapy. The rosemary group, on the other hand, showed decreased frontal alpha and beta power, suggesting increased alertness. They also had lower state anxiety scores, reported feeling more relaxed and alert and they were only faster, not more accurate, at completing the math computations after the aromatherapy session.
Article
Olfaction is typically described as behaviorally slow, suggesting neural processes on the order of hundreds of milliseconds to seconds as candidate mechanisms in the creation of olfactory percepts. Whereas a recent study challenged this view in suggesting that a single sniff was sufficient for optimal olfactory discrimination, a study by Abraham et al. in this issue of Neuron sets out to negate the challenge by demonstrating increased processing time for discrimination of similar versus dissimilar stimuli. Here we reconcile both studies, which in our view together support the notion of a speed-accuracy tradeoff in olfactory discriminations that are made within about 200 ms. These findings are discussed in light of the challenges related to defining olfactory perceptual similarity in nonhuman animals.
Article
Despite aromatherapy's popularity, efficacy data are scant, and potential mechanisms are controversial. This randomized controlled trial examined the psychological, autonomic, endocrine, and immune consequences of one purported relaxant odor (lavender), one stimulant odor (lemon), and a no-odor control (water), before and after a stressor (cold pressor); 56 healthy men and women were exposed to each of the odors during three separate visits. To assess the effects of expectancies, participants randomized to the "blind" condition were given no information about the odors they would smell; "primed" individuals were told what odors they would smell during the session, and what changes to expect. Experimenters were blind. Self-report and unobtrusive mood measures provided robust evidence that lemon oil reliably enhances positive mood compared to water and lavender regardless of expectancies or previous use of aromatherapy. Moreover, norepinephrine levels following the cold pressor remained elevated when subjects smelled lemon, compared to water or lavender. DTH responses to Candida were larger following inhalation of water than lemon or lavender. Odors did not reliably alter IL-6 and IL-10 production, salivary cortisol, heart rate or blood pressure, skin barrier repair following tape stripping, or pain ratings following the cold pressor.
The biology of odors, sources, olfaction and response
  • Y Masaoka
  • I Homma
Masaoka, Y. & Homma, I. (2011). Breathing for olfaction and emotion. In: L. E. Weiss & J. M. Atwood (Eds.), The biology of odors, sources, olfaction and response (pp. 295-307). New York: Nova Science Publishers.
Alphabet soup: Blurring the distinctions between p's and α's in psychological research
  • Hubbard
The number of olfactory stimuli that humans can discriminate is still unknown. eLife, 4:e08127
  • R C Gerkin
  • J B Castro
Gerkin, R. C. & Castro, J. B. (2015). The number of olfactory stimuli that humans can discriminate is still unknown. eLife, 4:e08127. DOI: 10.7554/eLife.08127.
Malignant side effects of null-hypothesis significance testing
  • W F Boron
  • E L Boulpaep
Boron, W. F., & Boulpaep, E. L. (2012). Medical physiology. Oxford: Elsevier. Branch, M. (2014). Malignant side effects of null-hypothesis significance testing. Theory and Psychology, 24, 256-277.
The number of olfactory stimuli that humans can discriminate is still unknown
  • Gerkin