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Preliminary investigation of the effect of peppermint oil on an objective measure of daytime sleepiness

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Abstract

The assertion, often quoted in the popular literature, that peppermint has invigorating properties has been investigated through objective assessment of daytime sleepiness. Pupillary fatigue oscillations have been used to give an index of pupillary unrest that can be used as a reliable measure of daytime sleepiness. When compared with a no-odour condition, the presence of peppermint oil limited the increase in sleepiness during 11 min spent in a darkened room. This significant difference in sleepiness between the peppermint oil and the no-odour conditions was shown not to be related to differences in subjective ratings of initial sleepiness, from the Stanford Sleepiness Scale (SSS). Neither was it related to differences in initial pupillary unrest or mean pupil size. It seems that in conditions that favour an increase in daytime sleepiness, peppermint oil can indeed reduce sleepiness. However, the mechanisms by which peppermint oil has its effect and the applicability of these findings to situations in everyday life will require further empirical investigation.

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... The malodor used by Rotton [4] was shown to have negative effects on well-being, further illustrating the noxious characteristics of the stimuli. However, a number of other studies have shown that positively rated odors can exert negative (as well as positive) effects on cognition, e.g., [5][6][7][8][9]. These findings illustrate that it is not a simple relationship between odor valence and cognitive performance, but that positively rated odors can have both positive and negative effects on cognition. ...
... Essential oils and other commercially available scents have, for example, been shown to positively affect memory, e.g., [5,6], vigilance, e.g., [7,10], pain perception, e.g., [11,12], self-perception/ confidence [13], consumer decision making, e.g., [14], and alertness, e.g., [8]. Jellinek [15] identified four potential mechanisms that might explain the odor-induced cognitive facilitation. ...
... Across a range of studies, odor exposure has been found to affect alertness and vigilance, e.g., [7,8]; for indirect facilitative effects see [50]. A relationship has been found between odor identification ability and resistance of vigilance to sleep deprivation [51]. ...
Article
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This paper reviews evidence that, in addition to incidental olfactory pollutants, intentional odor delivery can impact cognitive operations both positively and negatively. Evidence for cognitive facilitation/interference is reviewed alongside four potential explanations for odor-induced effects. It is concluded that the pharmacological properties of odors can induce changes in cognition. However, these effects can be accentuated/attenuated by the shift in mood following odor exposure, expectancy of cognitive effects, and cues to behavior via the contextual association with the odor. It is proposed that greater consideration is required in the intentional utilization of odors within both industrial and private locations, since differential effects are observed for odors with positive hedonic qualities.
... Specifically, chewing per se acts to reduce stress, but flavour induces a state of relaxation. Indeed, it is possible, therefore, that the mint flavour enhanced alertness (see Norrish and Dwyer, 2005). With respect to stress, Scholey et al. highlight that 5 brief stress exposure can cause short-term reductions in vasodilatation. ...
... In addition, this finding supports data from our laboratory (Johnson, Miles, Harrison, Haddrell, Osborne, Wilson, and Jenks, in preparation) showing that pupillary unrest (a physiological measure inversely associated with alertness, e.g. Norrish and Dwyer, 2005) is significantly reduced by a chewing gum condition compared to both sham and no chewing controls. The exact mechanism underpinning the increase in selfrated alertness is unclear but it may be driven by the mint flavour (e.g. ...
... The exact mechanism underpinning the increase in selfrated alertness is unclear but it may be driven by the mint flavour (e.g. see Norrish and Dwyer, 2005;Johnson and Miles, 2008). Alternatively, the proposed increase in cerebral activity following the chewing of gum (e.g. ...
Article
The finding that chewing gum can moderate stress and mood changes following a multi-task cognitive stressor (Scholey et al., 2009) was re-examined. In a repeated measures cross-over design, thirty participants completed a 20-min multi-tasking stressor on consecutive days, both with and without chewing gum. Both prior to and post stressor, participants provided salivary cortisol samples and self-rated measures of stress, state anxiety, calmness, contentedness, and alertness. Contrary to Scholey et al. (2009), chewing gum failed to attenuate both salivary cortisol levels and the increase in self-rated stress. Self-rated anxiety, calmness, and contentedness were not impacted by chewing gum. This suggests that the stress effects reported by Scholey et al. may be constrained by particular features of that study (e.g. morning testing). However, consistent with Scholey et al. (2009), chewing gum was shown to increase alertness following the stressor. The mechanisms underpinning heightened alertness are unclear; however, such increases may be linked to greater cerebral activity following the chewing of gum (Fang Li, Lu, Gong, & Yew, 2005).
... For example, mint flavour has been associated with increased alertness. Norrish and Dwyer [12] employed the Pupillograpy Sleepiness Test (PST) and demonstrated that exposure to a peppermint odour can attenuate pupillary unrest (an inverse correlate of self-rated alertness [13]). ...
... The PST measures fluctuations in the size of the pupil's diameter (pupillary oscillations), with darknessinduced changes in pupillary oscillations correlating significantly with self-rated alertness [13]. The pupillary oscillations in darkened conditions are determined by the inter-relation of sympathetic nervous activity matched with central parasympathetic inhibition (see [12,13,16] for reviews). Reductions in alertness are associated with decreases in both sympathetic nervous activity and central parasympathetic inhibition of the Edinger-Westphal nuclei; such reductions inhibit dilator and sphincter muscle control of the pupil diameter resulting in greater fluctuations of pupil size ( [13]). ...
... Previous studies ( [12]) suggest that the 11-minute PST will result in a significant increase in daytime sleepiness as indexed via an increase in PUI. If chewing gum has an effect on physiological daytime sleepiness, then chewing gum should limit the increase in PUI relative to both the sham chewing and no chewing controls. ...
Article
The proposition that chewing gum can improve alertness was investigated via both physiological and self-rated measures. The Pupillographic Sleepiness Test (PST) provided a measure of pupillary unrest (PUI); a physiological index of daytime sleepiness. Chewing gum reduced the extent of sleepiness as measured by both PUI and self-rated sleepiness. Specifically, in comparison with sham chewing and no chewing controls, the chewing gum condition significantly limited the increase in pupillary unrest following the 11-minute PST within a darkened laboratory: a finding indicating moderation of the daytime sleepiness increase for the chewing gum condition. In addition, there was some evidence that chewing gum (relative to the no-chewing condition only) moderated the increase in a self-rated measure of sleepiness (Stanford Sleepiness Scale). However, there was no evidence that chewing gum moderated the decrease in self-rated alertness (Bond-Lader Visual Analogue Mood Scale). Although the precise mechanism underpinning the effect of chewing gum is unclear, the reduction in daytime sleepiness may be underpinned via heightened cerebral activity following the chewing of gum or the arousing effects of mint flavour.
... Aromatherapy inhalation of the essential oil distilled from the leaves of Mentha x piperita (peppermint essential oil) has been found to reduce fatigue and to increase stamina in studies on general populations, but has not been evaluated in women with hypothyroidism. Norrish and Dwyer found that an eleven minute midday exposure to peppermint essential oil inhalation reduced daytime sleepiness in a small undergraduate mixed-gender sample, as measured through pupillary responses [18]. Aromatherapists have also found that peppermint essential oil inhalation reduces self-reported mental fatigue and burnout in a small, informal aromatherapy survey [19]. ...
... [24] to calculate the sample size required for the study. Peppermint essential oil inhalation was shown in previous work to have a large effect size, and the total uninflated sample size required for analysis to detect a difference between the aromatherapy inhalation group and the control group was 18, assuming a standard alpha of 0.95 and a power of 0.9 [18]. Because previous work has produced an unusually large effect size, the sample size was increased with a design effect of 1.5 to compensate for potential reductions in total effect size and failure of fidelity with the intent-to-treat design. ...
Article
Background This randomized, blinded, placebo-controlled clinical trial identifies the effect of an aromatherapy blend of essential oils on fatigue, which is one of the most commonly unaddressed symptoms of hypothyroidism, by evaluating the effects of daily aromatherapy inhalation. Methods Participants included women aged 18–55 with a diagnosis of hypothyroidism. Women who had a history of thyroid cancer were excluded, due to the confounding effects of cancer on fatigue as the outcome of interest. Participants were randomized into two groups: the aromatherapy group, treated with inhalation of the essential oil blend, and the control group, treated with an odorless vegetable oil blend. The primary outcome was change from baseline in fatigue scores as measured by the Multidimensional Fatigue Symptom Inventory (MFSI), a validated instrument which measures multiple patterns of fatigue. Results After adjusting for baseline scores, no significant difference was found between the aromatherapy group and the control group at midpoint. Both groups experienced a reduction in symptoms during the first week of the intervention. At the endpoint, participants in the aromatherapy group had improved fatigue scores across all ten subscales, as compared to the control group. Not all improvements achieved statistical significance, indicating that the aromatherapy treatment has a greater effect on the subscales of global, affective, and general fatigue. Conclusions This is the first study to evaluate the effects of aromatherapy on fatigue among women with hypothyroidism. These findings provide evidence that regular inhalation of an aromatherapy blend may reduce fatigue among women with hypothyroidism, particularly in the areas of global, affective, and general fatigue.
... In recent years, a small body of research has also delivered scientific investigations into the effects of peppermint aroma on a number of non-therapeutic variables, such as its limiting effects on daytime sleepiness [6]. Mahachandra and Garnaby [7] suggest that the stimulating properties of peppermint aroma might be utilised in in-car fragrance dispersal units to reduce driver sleepiness and have a positive impact on associated vehicle accidents. ...
... The authors suggest this is a consequence of increased physiological arousal producing increased awareness and attention to detail, although no measures of physiology or subjective mood were recorded. Norrish and Dwyer [6] investigated the effects of peppermint aroma on an objective measure of daytime sleepiness-the Pupillary Unrest Index-and found a very large effect (d = 1.6) in favour of peppermint aroma when compared to no aroma over an 11-minute recording period. This has been further reinforced by the measurement of subjective state during driving simulations where peppermint produced increases in alertness and reductions in perceptions of demand and fatigue [25]. ...
... Ho and Spence [139] found a significant performance improvement in the presence of peppermint odor. Norrish and Dwyer [140] reported that the presence of peppermint oil controlled the increase in sleepiness during 11 min spent in a darkened room when compared with a no-odor condition. Moss et al. [141] provided the evidence for the impact of the aromas of plant essential oils (ylang-ylang aroma, peppermint aroma) on aspects of cognition and mood. ...
... [129] 22. Peppermint oil Daytime sleepiness, peppermint oil can indeed reduce sleepiness. [140] 23. ...
Article
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The influence of fragrances such as perfumes and room fresheners on the psychophysiological activities of humans has been known for a long time, and its significance is gradually increasing in the medicinal and cosmetic industries. A fragrance consists of volatile chemicals with a molecular weight of less than 300 Da that humans perceive through the olfactory system. In humans, about 300 active olfactory receptor genes are devoted to detecting thousands of different fragrance molecules through a large family of olfactory receptors of a diverse protein sequence. The sense of smell plays an important role in the physiological effects of mood, stress, and working capacity. Electrophysiological studies have revealed that various fragrances affected spontaneous brain activities and cognitive functions, which are measured by an electroencephalograph (EEG). The EEG is a good temporal measure of responses in the central nervous system and it provides information about the physiological state of the brain both in health and disease. The EEG power spectrum is classified into different frequency bands such as delta (0.5–4 Hz), theta (4–8 Hz), alpha (8–13 Hz), beta (13–30 Hz) and gamma (30–50 Hz), and each band is correlated with different features of brain states. A quantitative EEG uses computer software to provide the topographic mapping of the brain activity in frontal, temporal, parietal and occipital brain regions. It is well known that decreases of alpha and beta activities and increases of delta and theta activities are associated with brain pathology and general cognitive decline. In the last few decades, many scientific studies were conducted to investigate the effect of inhalation of aroma on human brain functions. The studies have suggested a significant role for olfactory stimulation in the alteration of cognition, mood, and social behavior. This review aims to evaluate the available literature regarding the influence of fragrances on the psychophysiological activities of humans with special reference to EEG changes.
... 1,2 Empirical research has shown that various EOs are able to impact cognitive functions like memory, attention, vigilance, and alertness. [2][3][4][5][6][7] However, possible pharmacological and non-pharmacological mechanisms behind demonstrated effects of inhaled EOs are yet to be clarified. 8 It has been proposed that olfactory stimuli may have a specific effect on the limbic system, which in turn causes psychological and physiological changes. ...
Article
Essential oils (EOs) are widely used for various purposes, however, their claimed effects are often not supported by empirical data. Previous findings have highlighted the importance of psychological factors (e.g. expectations) in their mechanism of action. The present study investigated the effects of an ingested placebo pill and inhaled rosemary and lavender oils on alertness and heart rate, as well as actual and perceived performance in a sustained attention task. 128 young adults, randomly allocated to four groups (rosemary, lavender, placebo pill with stimulant suggestion, and control), completed a vigilance task before and after the respective intervention. Compared to the control condition, no effects of the three interventions were found on actual changes in sustained attention, alertness, or heart rate. Both EOs and the placebo pill evoked positive expectations regarding cognitive performance and alertness. Expectations predicted perceived changes in alertness and heart rate, but not in cognitive performance. No differences between the two EOs and the placebo intervention were found in any respect. Psychological mechanisms behind the effects of inhaled EOs and placebos might be overlapping.
... Eisenberg et al (1993) conducted a national survey in the US, finding that one in three respondents had used at least one alternative therapy in the last year (9). There is a lot of researches on effect of herb on psychological and physical disorder for example: Peppermint was found to enhance memory, increased alertness, but Yalang-Yalang decreased it (10), the beneficial effect of FEWP(Free and Easy Wander Plus) for mood disorder (11), the role of essential oils in the treatment of Attention Deficit Hyperactivity Disorder (ADHD) ( 12), the use of hypericum perforatum (St Johnson's wort) to treat depression, Ginkgo biloba to delay cognitive decline in patients with Alzheimer's disease (13), the effect of the herb on insomnia (14), the effect of odor compounds of Mint, Ostokhodoos and Rosemary on the stress of nursing students, indicated that depression and stress of the students have been reduced (15), effect of peppermint oil in irritable bowel syndrome (16), the other plants with CNS-effect used (17) and etc. All of the researches were mixed of some plants and M. Pipperita is one of them. ...
Article
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Depressive disorders are among the most important disabling diseases that have affected a large population throughout the world. This study has been carried out with the aim to determine the effect of Mentha pipperita on improving the symptoms in persons with depression as a co treatment. Methods: The effect of Mentha pipperita on depression was studied in a triple-blind random clinical trial. The applied tool was Beck questionnaire and the number of samples was 55. Collected data were analyzed using SPSS software taking the help of descriptive statistics, one-way Variance analysis and Variance analysis with repeated measurements. Results: The results of the research showed that, there was a statistical significant difference at the level of p=0.01 among under studied groups in such a way that's, Mentha pipperita reduced the symptoms of disease and improved the under research samples. Conclusion: Some plants could be used as treatment complementary in psychical disorders therefore; the necessity of more researches is felt in this regard.
... Peppermint oil utilized in this study was contained 30.70% of L-Menthol, 27.08% of L-Methone, 4.95% of Menthyl Acetate, 4.35% of Iso-Menthone, 4.79% of Mentha Furan, and 5.76% of Cineol. The aroma strength was justified by two random participants until they could smell the peppermint [14]. ...
Article
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The numbers of the traffic accidents related to human factors are increasing rapidly. Among all contributing factors to the accident, fatigue and sleepiness on wheel are the most common reasons. Both conditions decrease drivers’ alertness, resulting in performance decrement and accident risk increment. The alertness degradation is usually not well recognized by the drivers. Peppermint fragrance is commonly known on its freshness as medicine or aromatherapy. This research was conducted to examine the effectiveness of peppermint as a car freshener in order to maintain drivers’ alertness level. A within-subject design experiment was carried out in a car-driving simulator laboratory engaging twelve male participants. There were two driving conditions: with placebo and with peppermint fragrance. Placebo and peppermint fragrance was released continuously using an electric vaporizer. The participants’ alertness level was monitored via brainwave activities using electroencephalograph (EEG) along 30minutes of driving. Frequency analysis on EEG data was conducted to determine the alpha, theta, and beta power band on F3 and F4 of lobus frontal to generate the (α+θ)/β ratio. Results of this study demonstrated that the application of the peppermint car freshener resulted in lower slope of (α+θ)/β ratio rather than placebo condition (0.018 vs. 0.026), though the difference was not significant (p = 0.216). The results suggest that the peppermint is promising to be applied as in-vehicle fragrance in order to maintain drivers’ alertness. Further research can be conducted to test various method of fragrance exposure to get more substantial increase of alertness level.
... The second suggests that flavour acts to influence self-rated mood. For example, exposure to mint odour has been shown to both attenuate the rise in physiological markers of sleepiness 12 and improve performance on a behavioural vigilance task 13 . ...
Article
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Objectives: The present study examined the effect of chewing gum on sustained attention and associated changes in subjective alertness. Methods: In a within-participants design, 20 participants completed an extended version of the sustained attention response task (SART: Robertson et al., 1997), both with and without chewing gum. Self-rated measures of alertness, contentedness, and calmness were taken before and after the SART. Results: Chewing gum was associated with improved attentional task performance. This finding was not contingent upon a general decrease in attentional performance and was apparent at all stages of the task. Subjective measures of alertness, contentedness, and calmness were higher following the chewing of gum. Changes in sustained attention co-varied with subjective alertness. Discussion: The effects of chewing gum on attention and alertness are consistent with past literature and were not contingent on declines in attention. Additionally, we found evidence that gum-induced changes in self-rated alertness and attention are related. We found no support for the proposition that chewing gum can impair attention due to the division of resources.
... Apparently, only one study (Schreuder, Hoeksma, Smeets, & Semin, 2014) has examined the influence of odors on perceived duration. However, it is well known that odors can modulate emotions and affect cognition and behavior in different ways, e.g., vigilance (Gould & Martin, 2001), alertness (Norrish & Dwyer, 2005), pain perception (Marchand & Arsenault, 2002;Villemure, Slotnick, & Bushnell, 2003), visual attention (Michael, Jacquot, Millot, & Brand, 2003, and pitch of spoken language (Millot & Brand, 2001). Odors can also influence simple tasks such as Stroop effect (Finkelmeyer et al., 2010) and reaction time (Millot, Brand, & Morand, 2002). ...
Article
Environmental stimuli can influence time perception, including sensory stimulations. Among them, odors are known to modulate emotion, attention, behavior, or performance, but few studies have investigated the possible effects of ambient odors on time perception. Thus, the present study aimed to compare in a retrospective paradigm the time estimation in three conditions, i.e., with phenyl ethyl alcohol as a pleasant odor, pyridine as unpleasant odor, and a control condition without ambient odor. A total of 90 participants (M age = 23 years, 10 months) took part in three different tasks, i.e., an aesthetic classification task, a sensorimotor checking task, and a mathematical operations task. Results showed a better accuracy of the time estimation in odor condition (1) independently of the characteristics of odorants (2) limited to tasks with a low cognitive involvement. These findings are discussed in relation to the possible role of attention and arousal in the modulation of time perception by ambient odors.
... Even though the existence of peppermint oil fades out the increase in daytime sleepiness linked with sitting in dark rooms, but still it is not apparent from this investigation that peppermint oil has actually antisleep-inducing actions or the competence to interrupt the inception of sleep. Therefore in order to support the viewpoints about the invigorating effects of peppermint oil, there is a need to go for empirical research investigations related to the substantiation of claims of its capacity to keep people invigorated and active, especially during night-time work shifts [29]. Ethnoveterinary effects M. piperita (peppermint) was found to have ethnoveterinary potential as it has been documented to address the abdominal troubles including the control of gastrointestinal parasites in cats, dogs and pigs of the British Columbian region of Canada. ...
Article
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Apart from its use for culinary purposes and as a home remedy for minor ailments, not many people are aware of the other “great” benefits of mint (Mentha spp.). Through this review article an attempt has been made to explore the emerging potential of mint (Mentha spp.) for treatment of various major diseases and promising action as an insecticide and repellent, as well as its potential application as a natural food preservative. This article justifies the emerging notion regarding adoption of safer and natural alternatives to the conventional antibiotics, medications and synthetic food preservatives carrying hazards in the form of numerous undesirable side effects.
... These relative contributions of each component of mastication, flavour and odour could be disentangled empirically by a partial replication of the current study but comparing the effects of unflavoured and flavoured gums with the addition of odour inhalation . For example it is known that menthol odour may have differential effects on mood and performance [36,37]. The results of this study do raise the question as to whether specific properties of gum contribute to the phenomenon described here or whether chewing anything might be an effective anti-stressor. ...
Article
The notion that chewing gum may relieve stress was investigated in a controlled laboratory experiment. The defined intensity stress simulator (DISS) is a multi-tasking platform which reliably induces stress and also includes performance measures. Using a partial crossover design 40 participants (mean age 22 years) underwent two intensities of the DISS while chewing and not chewing. Before and after completing the DISS participants completed the state portion of the State-Trait Anxiety Inventory, Bond-Lader visual analogue mood scales and a single stress visual analogue scale. Salivary cortisol levels were co-monitored. Baseline measures revealed that both levels of stress were effective in significantly reducing self-rated alertness, calmness and contentment while increasing self-rated stress and state anxiety. Cortisol levels fell during both levels of the stressor during the morning but this effect was reversed in the afternoon. Pre-post DISS changes (Δ) for each measure at baseline were subtracted from Δ scores under chewing and no chewing conditions. During both levels of stress the chewing gum condition was associated with significantly better alertness and reduced state anxiety, stress and salivary cortisol. Overall performance on the DISS was also significantly better in the chewing condition. The mechanisms underlying these effects are unknown but may involve neurohormonal interactions during the cephalic phase, improved cerebral blood flow and/or effects which were secondary to performance.
... Furthermore, neuro-imaging studies have shown that oral CO 2 triggers the immediate activation of a wide network of brain regions mediating alertness and cognitive functions [25,26]. For example, other trigeminal stimulations, such as the cooling compound of mint (menthol, TRPM8 agonist), have been consistently associated with rapid and immediate stimulatory effects in humans, including reduced sleepiness [27], increased sustained attention [28][29][30], improved alertness [30] and enhanced physiological arousal (cortical excitability) [31][32][33]. Despite this evidence, it is surprising that only one study [2] has investigated the acute effect of a carbonated caffeinated product on mood and cognition. ...
Article
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Both caffeine and the perception of refreshment delivered by cooling, tingling, and mouth-watering flavors have individually been shown to positively impact cognitive performance and mood, though presently there is limited evidence on their possible combined effects. This study explored the contribution of refreshing compounds in beverages, namely, carbon dioxide and citric acid, on the acute effects of caffeine on sustained attention and self-rated physical and mental energy. A randomized, controlled crossover trial was conducted by testing three products: a carbonated caffeinated beverage; a comparator caffeinated beverage; and a flavor-matched control beverage. Findings from 24 healthy adults revealed product-dependent variations in cognitive performance during a 60-min visual sustained-attention task, suggesting that the carbonated-caffeinated beverage led to faster, greater and more consistent levels of accuracy, compared to the control beverage. Specifically, significant differences were found between: (1) the carbonated-caffeinated beverage and the caffeinated beverage, and (2) between the caffeinated beverage and the control beverage for number of hits, reaction time and false alarm scores. Both caffeinated beverages led to higher physical and mental energy, and lower physical and mental fatigue 60-min post-consumption. These findings suggest beneficial effects on sustained attention through the combination of caffeine with refreshing compounds.
... We chose to compare preferred music to odours because ambient smells can influence behaviour, emotion and affect cognition in healthy subjects [12,13]. Influence is found for example on vigilance [14], alertness [15], pain perception [16], visual attention [17], reaction time [18], as well as simple tasks [19], and complex memory tasks [20]. Behavioural vigilance performance is also improved in patients with brain injury [21]. ...
Article
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Background: Reliable evaluation of patients with unresponsive wakefulness syndrome (UWS) or in a minimally conscious state (MCS) remains a major challenge. It has been suggested that the expression of residual cerebral function could be improved by allowing patients to listen to their favourite music. However, the potential effect of music on behavioural responsiveness, as well as the effect of preferred stimuli in other sensory modalities (e.g. olfaction), remain poorly understood. Objective: The aim of our study was to investigate the effect of sensory modality (auditory versus olfactory) and preference (preferred versus neutral) of the test stimuli on patients' subsequent performance on the Coma Recovery Scale-Revised (CRS-R). Research design: Within-subject design because of inter-individual differences between patients. Methods and procedures: We studied four items from the CRS-R (visual pursuit using a mirror, auditory localization of the own name and two movements to command) in 13 patients (7 MCS; 6 UWS). Main outcomes and results: Auditory stimuli triggered higher responsiveness compared to olfactory stimuli, and preferred stimuli were followed by higher scores than did neutral stimuli. Conclusions: Findings suggest that preferred auditory stimuli at the bedside contribute to the expression of residual function and could improve the diagnostic assessment.
... Essential oils (EOs) and other odorous materials have long been used in various aspects of everyday life as well as in medicine throughout human history (16,62). EOs have an impact on memory functions (50), perception of pain (42,44,63), vigilance and alertness (53,66), and mood (18,50,51). From practical point of view, EOs can be used to reduce anxiety before dental interventions (21,(39)(40)(41)52) or to improve attention or reaction time in particularly demanding tasks (25,29,49). ...
Article
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Effects of inhaled essential oils (EOs) cannot be explained by pharmacological mechanisms alone. The study aimed to investigate the effects of pleasantness of and expectancies evoked by EOs. A double-blind experiment with a within-subject design was carried out with the participation of 33 volunteering adults (15.2% male; mean age 37.7 ± 10.90 years). Participants were exposed to three EOs (rosemary, lavender, and eucalyptus) for three minutes in a quasi-random order, expectations were simply assessed prior to exposure. Subjective (perceived) changes in alertness, heart rate (HR), and blood pressure (BP), and objective changes in HR, BP, and indices of heart rate variability were recorded. Significant group-level differences in changes in alertness and no differences for the cardiovascular variables were found. Participants' expectations predicted changes in alertness in the case of rosemary and lavender oils but had no impact on cardiovascular variables. EOs' pleasantness had no effect on any assessed variable. Perceived changes in BP and HR were not related to the respective objective changes but were connected to perceived changes in alertness. Expectancies play an important role in the subjective effects of inhaled EOs. Perceived subjective changes are used to estimate changes in non-conscious (e.g., visceral) states.
... Last, the taste of gum and the relaxing effects of chewing the sweet and flavored gum (the SAP of the sapodilla tree) were first suggested by Hollingworth in 1939 [29]. It was known that menthol may have a soothing effect on anxiety and stress [30,31], similar to what Hollingworth has mentioned. ...
Article
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There was currently no consensus on whether chewing gum should be widely instituted as a means to help reduce anxiety and stress. Chewing gum was also not included in guidelines for alleviating anxiety and stress. The purpose of this study was of two aspects: (1) to review the research progress of the relationship between gum chewing and anxiety and stress in recent years and (2) to make a meta-analysis of the effects of mastication on anxiety and stress. We conducted a meta-analysis of studies extracted from PubMed, the Cochrane Library, and Embase to identify randomized controlled trials (RCTs) evaluating the efficacy of chewing gum on anxiety, and stress was evaluated through screening, inclusion, data extraction, and quality assessment. The meta-analysis we performed was using Review Manager 5.3 software. We included a total of 8 RCTs, involving more than 400 adults over 18 years old. Compared with no chewing gum, chewing gum resulted in anxiety (MD = −0.26, 95% CI (−0.48, −0.04), p = 0.02 , I2 = 11%), where the heterogeneity was low and statistically significant. While in stress (MD = −0.27, 95% CI (−0.79, −0.25), p = 0.31 , I2 = 48%), the heterogeneity was high, and there was of no statistical significance. Based on current evidence, chewing gum is an inexpensive, well-tolerated, safe, and effective way to relieve anxiety and stress. To confirm the conclusion, we still need to conduct more randomized trials.
... levandulový a vetiverový olej, vanilin, sulfid amonný). Je možné, že některé odoranty mohou spánek naopak narušovat (Komori et al., 2006;Norrish a Dwyer, 2005). ...
Article
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The association between sleep and chemosensory research represents a seemingly unlikely yet all the more fruitful alliance overlapping with other disciplines, such as cognitive and affective science. Olfactory perception in sleep represents an exception among the sensory modalities in that, in contrast to the other senses, suprathreshold olfactory stimulation does not trigger arousal or waking. Under certain conditions odors can even promote sleep. This promises a wide scope of application in the research context as well as clinical practice. The aim of the study is to outline the characteristics of olfactory processing in sleep and present ways in which they may be utilized in the research of dreams or memory consolidation.
... Peppermint (Mentha x piperita) is renowned for its stimulant properties. Inhalation of the aroma of its essential oil reduces daytime sleepiness (Norrish et al., 2005); enhances alertness, motivation and performance on a driving task (Raudenbush et al., 2009); and improves long term memory and attentional speed (Moss et al., 2008). The potential impact on prospective memory has not been previously reported, and the relationship between changes in subjective mood state and objective measures of performance are still unclear. ...
Conference Paper
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Objectives: This study aimed to identify if prospective memory performance might be facilitated by peppermint aroma and if any effects observed were associated with changes in self-reported mood. Design: A one-factor independent groups design was employed in this study. Prospective memory performance was assessed in either peppermint aroma or no aroma conditions. Self-reported mood was recorded prior to and after completion of the prospective memory assessment. Methods: 90 healthy adult volunteers took part in the study and were randomly allocated to one of the two conditions. Peppermint aroma was produced by diffusing four drops of the essential oil of Mentha x pierita in one of two testing rooms prior to testing. Participants completed the first mood scale prior to entering the testing room. All participants then completed the CAMPROMPT test of prospective memory (Pearson UK) in one of the testing rooms, and finally the second mood scale. Data from the CAMPROMPT were analysed using a Manova with the time and event based measures acting as the dependent variables and condition as the between groups factor. Data from the mood scales Alert, Calm and Content were analysed using mixed factorial Anovas with pre-post acting as the repeated measures factor and condition the between groups factor. Results: Peppermint aroma significantly enhanced prospective memory Wilks’ ?=.011, F(2,87)=5.061, p=.008. Bonferroni corrected univariate Anovas indicated that both Time based [F(1,88)=7.725, p=.014, partial eta2=.081], and Event based [F(1,88)=6.347, p=.028, partial eta2=.067] measures of prospective memory were positively affected. No significant main effect of aroma or interaction between aroma and pre-post testing were found for any of the mood measures. Conclusions: The aroma of the essential oil of peppermint significantly enhanced prospective memory in healthy adults. The effect sizes are consistent with those previously identified for other aspects of cognition. The non-significant impact on mood suggests that the influence of aroma on prospective memory is independent of subjective state. This latter conclusion supports the contention that aromas might exert their influence via central pharmacological mechanisms.
... Peppermint is indeed widely reported to possess stimulating and invigorating properties. As compared to air, ambient exposure to peppermint oil was found to reduce sleepiness [65], improve subjective alertness [66] and enhance performance in a range of cognitive tasks assessing attention and memory functions [66][67][68][69][70]. Eccles suggested that the activation of nasal cold receptors by menthol is similar to "taking a breath of fresh air," leading to an increased level of alertness, or "cortical activation" [43], as defined earlier [71]. To illustrate his point, Eccles reported the example of the use of 'smelling salts', containing trigeminal stimulants such as menthol and ammonia, to arouse someone who has temporarily lost consciousness. ...
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Refreshing is a term often used to characterize certain types of foods and beverages. This review first explores what is known from sensory and consumer studies on refreshing perception in relation to food and beverage consumption. It then presents and discusses the similarities between sensory characteristics perceived as refreshing with those perceived during and after drinking water. In general, refreshing drinks and beverages seem to help alleviate symptoms experienced during water deprivation, including thirst, mouth dryness and mental fatigue. The role that learning may have in the construction of refreshing perception during each food experience is also discussed. The review showed that a refreshing value (perceived or expected) tends to be associated with foods sharing some characteristics with water in terms of their sensory profile (clear, cold, liquid); and that food experiences may induce associative learning about perceptions of existing or new products marketed as refreshing.
... Additionally, in the present, we have shown that peppermint can enhance the quality of sleep in the students. Inhaling peppermint odor has also been studied in relation to sleep and found to significantly decreased daytime sleepiness (Norrish and Dwyer, 2005) and has a stimulating and sedating effect when inhaled before bedtime with total sleep and more slow-wave sleep when compared with a no-odor control (Goel and Lao, 2006). ...
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Resumen Context: Stress, sleep disorders, and anxiety are common mental health problems affecting many university students. Peppermint, as a traditional herb, may be used as an alternative to stimulant drugs with less adverse effects to deal with mental health problems of the students. Aims: To evaluate the impact of oral Mentha piperita (peppermint) on self-reported memory performance, anxiety, stress, and the quality of sleep in science students at Taibah University. Methods: Eligible participating students were allocated either to the experimental group or the control group. The experimental group was asked to drink either an infusion of fresh aerial parts of peppermint once a day for four weeks, and the control group asked not to drink any peppermint or any other herbs during the study (no treatment). Anxiety, stress, memory performance, and sleep quality of the participating student were assessed by self-reported questionnaires before and after the peppermint treatment. Anxiety in the students was assessed by the State-Trait Anxiety Inventory, memory performance was evaluated using the Prospective and Retrospective Memory questionnaire and the Pittsburgh Sleep Quality Index was used to assess the sleep quality and patterns in students. Results: The scores of all the scales and subscales of the State-Trait Anxiety Inventory, Prospective and Retrospective Memory, and the Pittsburgh Sleep Quality Index were significantly decreased in the peppermint group in comparison with the control group after four weeks. Conclusions: Peppermint appears to significantly enhance memory, reduce anxiety and stress, and improve the sleep quality of university students. Contexto: El estrés, los trastornos del sueño y la ansiedad son problemas de salud mental comunes que afectan a muchos estudiantes universitarios. La menta, como hierba tradicional, se puede utilizar como alternativa a las drogas estimulantes con menos efectos adversos para tratar los problemas de salud mental de los estudiantes. Objetivos: Evaluar el impacto de la Mentha piperita (menta) oral en el rendimiento autoinformado de la memoria, la ansiedad, el estrés y la calidad del sueño en estudiantes de ciencias de la Universidad de Taibah. Métodos: Los estudiantes participantes elegibles fueron asignados a los grupos experimental o control. Se pidió al grupo experimental que bebiera una infusión de partes aéreas frescas de menta una vez al día durante cuatro semanas, y al grupo de control se le pidió que no bebiera menta ni ninguna otra hierba durante el estudio (sin tratamiento). La ansiedad, el estrés, el rendimiento de la memoria y la calidad del sueño del estudiante participante se evaluaron mediante cuestionarios autoinformados antes y después del tratamiento con menta. La ansiedad en los estudiantes se evaluó mediante el inventario de ansiedad de rasgo estatal, el rendimiento de la memoria se evaluó mediante el cuestionario de memoria prospectiva y retrospectiva y el índice de calidad del sueño de Pittsburgh se utilizó para evaluar la calidad y los patrones del sueño en los estudiantes. Resultados: Las puntuaciones de todas las escalas y subescalas del inventario de ansiedad rasgo del estado, la memoria prospectiva y retrospectiva y el índice de calidad del sueño de Pittsburgh disminuyeron significativamente en el grupo de menta en comparación con el grupo de control después de cuatro semanas. Conclusiones: La menta parece mejorar significativamente la memoria, reducir la ansiedad y el estrés y mejorar la calidad del sueño de los estudiantes universitarios.
... Additionally, in the present, we have shown that peppermint can enhance the quality of sleep in the students. Inhaling peppermint odor has also been studied in relation to sleep and found to significantly decreased daytime sleepiness (Norrish and Dwyer, 2005) and has a stimulating and sedating effect when inhaled before bedtime with total sleep and more slow-wave sleep when compared with a no-odor control (Goel and Lao, 2006). ...
Article
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Context: Stress, sleep disorders, and anxiety are common mental health problems affecting many university students. Peppermint, as a traditional herb, may be used as an alternative to stimulant drugs with less adverse effects to deal with mental health problems of the students. Aims: To evaluate the impact of oral Mentha piperita (peppermint) on self-reported memory performance, anxiety, stress, and the quality of sleep in science students at Taibah University. Methods: Eligible participating students were allocated either to the experimental group or the control group. The experimental group was asked to drink either an infusion of fresh aerial parts of peppermint once a day for four weeks, and the control group asked not to drink any peppermint or any other herbs during the study (no treatment). Anxiety, stress, memory performance, and sleep quality of the participating student were assessed by self-reported questionnaires before and after the peppermint treatment. Anxiety in the students was assessed by the State-Trait Anxiety Inventory, memory performance was evaluated using the Prospective and Retrospective Memory questionnaire and the Pittsburgh Sleep Quality Index was used to assess the sleep quality and patterns in students. Results: The scores of all the scales and subscales of the State-Trait Anxiety Inventory, Prospective and Retrospective Memory, and the Pittsburgh Sleep Quality Index were significantly decreased in the peppermint group in comparison with the control group after four weeks. Conclusions: Peppermint appears to significantly enhance memory, reduce anxiety and stress, and improve the sleep quality of university students.
... The number of odours that have been convincingly demonstrated to promote sleep is very limited (for review see [109]) and the exact mechanisms whereby they can exert their influence on the sleeping brain are not known. The vast majority of olfactory stimuli show no effect on sleep and some may even disturb or shorten it [110,111]. ...
Article
Previous laboratory research has shown that exposure to odours of contrasting pleasantness during sleep differentially affects the emotional tone of dreams. In the present study, we sought to investigate how a generally pleasant (vanillin) and unpleasant (thioglycolic acid, TGA) smell influenced various dream characteristics, dream emotions and post-sleep core affect during all-night exposure, controlling for appraisal of the olfactory environment during the assessments and sleep stage from which the participants woke up. We expected that exposure to vanillin would result in more pleasant dreams, more positive and less negative dream emotions, and more positive post-sleep core affect compared to the control condition, whereas exposure to TGA would have the opposite effect. Sixty healthy volunteers (37 males, mean age 23 ± 4 years) were invited to visit the sleep laboratory three times in weekly intervals. The first visit served to adapt the participants to the laboratory environment. On the second visit half the participants were exposed to odour (vanillin or TGA, 1:1) and the other half to the odourless control condition. On the third visit, they received control or exposure in a balanced order. On each visit, the participants woke up twice, first from the rapid eye movement (REM) sleep stage and then in the morning, mostly from non-REM. Repeated measures were taken upon each awakening of dream pleasantness, emotional charge of the dream, positive and negative emotions experienced in the dream, and four dimensions of post-sleep core affect (valence, activation, pleasant activation – unpleasant deactivation, and unpleasant activation – pleasant deactivation). We found a small effect of condition (exposure vs. control) in interaction with appraisal on the ambient olfactory environment on dream pleasantness. Specifically, false alarms (i.e., perceiving odour in the absence of the target stimulus) were associated with lesser dream pleasantness than correct rejections. Although exposure had a statistically significant positive influence on post-sleep core affect (namely, valence, activation, and pleasant activation – unpleasant activation), the size of the effect was small and lacked practical significance. The hypothesised differential effects of vanillin and TGA were only modelled for dream ratings because they decreased the fit of the other models. Neither dream pleasantness nor emotionality differed according to the odour used for stimulation. The results of the present study suggest that all-night exposure to odours is unlikely to produce practically significant positive effects on dreams and post-sleep core affect.
... By TIM, mint induces a feeling of hap-piness, strengthens stomach, removes waste, relieves pain and treats digestion disorder. Research has shown that besides anti-bacterial, anti-depressive, anti-soporific and analgesic features (33), mint is also antispasmodic. It seems peppermint oil with its calcium influx blocking feature can treat bloating through its antispasmodic effect on smooth muscles of digestive tract (13,34). ...
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Context: Functional dyspepsia (FD) is a functional gastro-intestinal disorder with high prevalence. Among various treatment options, treatment by complementary and alternative medicines especially herbal remedies also practiced. Traditional Iranian medicine (TIM), a valuable resource of valid applied studies of ancient Iranian scholars, recommends numerous medicinal plants to treat dyspepsia symptoms. In this study, through investigation of TIM references, we aimed to identify medicinal plants for treatment of digestion insufficiency. Evidence acquisition: In this qualitative study, dyspepsia symptoms including fullness, early satiety, bloating, nausea, and belching were checked under reliable sources of traditional medicine. Then medicinal plants recommended for the treatment of the symptoms were extracted from the books. Likewise, for investigating the pharmacological properties of medicinal plants used for the relieving of dyspepsia symptoms, electronic databases such as PubMed, Scopus, Google Scholar and some Iranian databases like SID and IranMedex were employed. Results: The study yielded 105 plants from 37 families which could treat various dyspepsia symptoms; fifty-seven plants, mainly from Apiaceae, Lamiaceae, Amaryllidaceae and Zingiberaceae had digestive effects. In this research, based on the information in TIM reference texts, we obtained 58 plants effective for bloating, 40 for nausea, 37 for appetite loss and 7 for belching. In human clinical trials conducted on medicinal plants effective for FD symptoms, 7 single plants were used. Conclusions: Finding the medicinal plants effective on digestion insufficiency based on TIM could suggest a better strategy for the relieving of dyspepsia symptoms. Traditional Iranian medicine prescribes medicinal plants based on each patient's personal characteristics and practices multiple target therapies.
Chapter
Erfahrungsberichten aus der Aromatherapie-Literatur zufolge [1,2] sollen Duftstoffe in der Lage sein, die Aktiviertheit zu beeinflussen, ja sogar zu optimieren. Doch können Gerüche uns wirklich munter machen, wenn die Nacht wieder einmal kurz war, wir aber trotzdem unsere Leistung in der Arbeitswelt erbringen müssen? Können sie uns im Gegenzug helfen, uns zu entspannen, wenn Stress und Leistungsdruck uns zu übermannen drohen? Können sie unsere Stimmung aufhellen oder uns die Angst vorm Zahnarzt nehmen? Und wenn ja, wie und in welchem Ausmaß? Wo sind die Grenzen der Wirksamkeit von Aromen? Diesen und ähnlichen Fragen wird erst seit wenigen Jahrzehnten in wissenschaftlichen Untersuchungen nachgegangen. Die Methoden, mit denen die Wirksamkeit von Duftstoffen überprüft wird, sind höchst vielfältig. So erstaunt es nicht, dass die Ergebnisse solcher Studien komplex und zum Teil widersprüchlich sind. In diesem Kapitel wird ein kritischer Überblick über die wissenschaftliche Literatur der letzten 15 Jahre gegeben. Die Auswahl beschränkt sich dabei auf Studien im Humanbereich, die sich mit der Messung von Aktiviertheit auf einer oder mehreren Ebenen befassen und bei denen Riechstoffe entweder durch Inhalation oder durch Resorption durch die Haut präsentiert werden. Da ein vollständiger Überblick über die vorhandene Literatur zu diesem Thema den Rahmen dieses Beitrags bei Weitem sprengen würde, wurde das Hauptaugenmerk bei der Auswahl der Texte auf neuere Gruppenuntersuchungen gelegt, die in wissenschaftlichen Zeitschriften mit „peer review“ veröffentlicht wurden, während Einzelfallstudien nicht berücksichtigt wurden. Das Ziel dieses Textes ist es, dem Leser ein Inventarium zur Verfügung zu stellen, mit dem er die zuvor gestellten Fragen beantworten kann. Literatur 1 Tisserand R (1977) The Art of Aromatherapy. London: CW Daniel 2 Valnet J (1990) The Practice of Aromatherapy. Rochester (VT): Inner Traditions.
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The aim of the present research was to evaluate the effect of refreshing perception on mental energy in terms of cortical activation and cognitive performance. Refreshing perception was induced by the consumption of an optimized citrus-flavored water ice with specific sensory properties leading to cooling and mouth-wetting sensations. Comparison treatments were standard water ices differing in refreshing intensity but matched in flavor and energy content, and a glass of water. In a first experiment, electroencephalographic activity of participants was monitored while performing a task of sustained attention. Relative to both comparison treatments, results revealed that the optimized water ice improved cortical activation in the alpha and beta powers known to be involved in neural circuits of attention, working memory and sensory-motor integration. In a second experiment, results revealed improved performance of attention after consumption of the optimized water ice relative to comparison treatments. Altogether, our results provide preliminary evidence supporting the beneficial impact of refreshing perception, reflected in the enhancement of cortical activation necessary for recruiting optimal resources for task performance.
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Peppermint oil is obtained from the leaves of the perennial herb, Mentha piperita L. and M. arvensis var. piperascens a member of the Labiatae family. This family includes many well-known essential oil plants such as spearmint, basil, lavender, rosemary, sage, marjoram and thyme. This is a well known and important medicinal plant widely used in several indigenous systems of medicine for various therapeutic benefits viz. analgesic, anesthetic, antiseptic, astringent, carminative, decongestant, expectorant, nervine, stimulant, stomachic, inflammatory diseases, ulcer and stomach problems. The present review is an up-to-date and comprehensive analysis of the chemistry, pharmacology, analysis, and uses of Peppermint oil.
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Objectives: To verify the effectiveness of aromatherapy massage on elderly patients under long-term hospitalization. Design: Aromatherapy massage was performed twice a week for a total of eight times. Setting: Nursing home. Subjects: Elderly women under long-term hospitalization. Interventions: Questionnaire and measurement of stress marker levels (salivary amylase activity) before and after the first, fifth, and eighth aromatherapy massages. Outcome measures: Questionnaire (Face scale, General Health Questionnaire-12 [GHQ-12]), measurement of salivary amylase activity. Results: A decrease in stress after aromatherapy massage compared to before each massage was confirmed at all measurement times and with the stress marker. No marked reduction was observed in Face scale or saliva amylase activity as a whole over the long term, although decreasing tendencies were seen. Marked reductions in GHQ-12 were observed over the long term. Conclusions: Aroma massage appears likely to prove effective in reducing psychological stress among elderly patients under long-term hospitalization.
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Pupillary response has been used as an index of sleepiness, but the validity of the index is not clear. In this paper, the influence of blinks on the Pupillary Unrest Index (PUI) and the Power Spectrum Density (PSD) as indices of pupil instability during a sleepiness test was examined. To create pupillary indices for sleepiness, four frequency components of the compensated pupillary change were extracted from PSD. These factor components were applied to two-class classifications of subjective sleepiness using discriminant analysis, and their performance was assessed. Differences in contribution ratios for the four factor components were observed between the two kinds of subjective sleepiness. Finally, a causal path diagram was created to show the relationship between blink, pupillary indices and subjective sleepiness.
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Ein Überblick über die relevante Literatur zum Thema zeigt, dass bei Wirkungen von Duftstoffen auf die Aktivierung auf physiologischer, emotionaler und kognitiver Ebene prinzipiell zwischen Anwendungen, die den Geruchssinn einschließen, und solchen, die ihn gänzlich umgehen, unterschieden werden muss. Obwohl auch bei letzteren nicht grundsätzlich ausgeschlossen werden kann, dass pharmakologische Wirkungen von Riechstoffen gemeinsam mit nicht-pharmakologischen Effekten auftreten, die sich aus dem Erfahrungshintergrund des Behandelten wie auch aus der Interaktion zwischen dem Patienten und dem Therapeuten ergeben können, liegt die Wahrscheinlichkeit für das Auftreten rein pharmakologisch vermittelter Wirkungen von Riechstoffen insofern höher, als zumindest rein mit dem Geruch der verabreichten Substanz assoziierte Wirkungen ausgeschlossen werden können.
Conference Paper
Pupillary response has been used for an index of sleepiness, but the validity of the index is not clear. In this paper, the influence of blinks on the Pupillary Unrest Index (PUI) and the Power Spectrum Density (PSD) for the frequency range 0.01 < f < 0.8Hz, as indices of pupil's instability during a sleepiness test, was examined. To estimate pupil size during blink, a procedure for collecting the clinical data was developed using Support Vector Regression (SVR). The values of PUI increased with experimental time, and the values and deviations of PUI for experimental observation were larger than the ones with SVR estimation. The blink time also increased with experimental time, and there were significant correlation relationships between the value of PUI and blink time. The mean PSD also correlated significantly with blink time. The relationship between pupillary indices and a subjective sleepiness index was not significant, as it was not in other previous works. These results provide evidence that pupillary indices were significantly affected by blink, and they did not reflect sleepiness correctly.
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Perceptual interactions between different sensory modalities affect overall perception of food. This phenomenon has been extensively investigated between olfactory and tastant stimuli in aqueous solutions. But few studies assessed olfactory and taste interactions in existing products (commercially available). Similarly multi-sensory perceptual interactions involving olfaction, taste and in mouth tactile perceptions and complex perceptions (i.e. a perception which is driven by more than one sensory dimension) have been poorly investigated. The first objective of my thesis was to investigate mechanisms underlying perceptual interactions between bimodal olfactory and taste perceptions in existing products and then in solutions with olfactory stimuli at a subthreshold concentration. This approach was extended to olfactory, taste and in mouth tactile perceptions and finally to "refreshing" complex perception. I showed that product familiarity and attentional strategy applied during exposure are critical factors modulating perceptual interactions. I demonstrated for the first time that subthreshold odorant concentrations related to sweet taste (i.e. strawberry) increase perceived sweetness of a sucrose solution. The multiplicity of perceptual interactions in complex food systems was demonstrated since I identified bimodal (e.g. between bitterness and coldness) and tri-modal (e.g. between mint aroma, sweetness and coldness) perceptual interactions. Finally I showed that refreshing perception is driven by positive and negative sensory drivers, food habits, together with hedonic and psychophysiological factors such as mental energy. To conclude, knowledge acquired during this work raised new questions; in particular related to neural mechanisms underlying memorization of perceptual associations and required conditions in terms of exposure duration and frequency for construction of such interactions.
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Introduction: Depressive disorders are among the most important disabling diseases that have affected a large population throughout the world. This study has been carried out with the aim to determine the effect of Mentha pipperita on improving the symptoms in persons with depression as a co treatment. Methods: The effect of Mentha pipperita on depression was studied in a triple-blind random clinical trial. The applied tool was Beck questionnaire and the number of samples was 55. Collected data were analyzed using SPSS software taking the help of descriptive statistics, one-way Variance analysis and Variance analysis with repeated measurements. Results: The results of the research showed that, there was a statistical significant difference at the level of p=0.01 among under studied groups in such a way that's, Mentha pipperita reduced the symptoms of disease and improved the under research samples. Conclusion: Some plants could be used as treatment complementary in psychical disorders therefore; the necessity of more researches is felt in this regard.
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Perceptual interactions between different sensory modalities affect overall perception of food. This phenomenon has been extensively investigated between olfactory and tastant stimuli in aqueous solutions. But few studies assessed olfactory and taste interactions in existing products (commercially available). Similarly multi-sensory perceptual interactions involving olfaction, taste and in mouth tactile perceptions and complex perceptions (i.e. a perception which is driven by more than one sensory dimension) have been poorly investigated. The first objective of my thesis was to investigate mechanisms underlying perceptual interactions between bimodal olfactory and taste perceptions in existing products and then in solutions with olfactory stimuli at a subthreshold concentration. This approach was extended to olfactory, taste and in mouth tactile perceptions and finally to "refreshing" complex perception. I showed that product familiarity and attentional strategy applied during exposure are critical factors modulating perceptual interactions. I demonstrated for the first time that subthreshold odorant concentrations related to sweet taste (i.e. strawberry) increase perceived sweetness of a sucrose solution. The multiplicity of perceptual interactions in complex food systems was demonstrated since I identified bimodal (e.g. between bitterness and coldness) and tri-modal (e.g. between mint aroma, sweetness and coldness) perceptual interactions. Finally I showed that refreshing perception is driven by positive and negative sensory drivers, food habits, together with hedonic and psychophysiological factors such as mental energy. To conclude, knowledge acquired during this work raised new questions; in particular related to neural mechanisms underlying memorization of perceptual associations and required conditions in terms of exposure duration and frequency for construction of such interactions.
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Most forms of supra-threshold sensory stimulation perturb sleep. In contrast, presentation of pure olfactory or mild trigeminal odorants does not lead to behavioral or physiological arousal. In fact, some odors promote objective and subjective measures of sleep quality in humans and rodents. The brain mechanisms underlying these sleep protective properties of olfaction remain unclear. Slow oscillations in the electroencephalogram (EEG) are a marker of deep sleep, and K-complexes (KCs) are an EEG marker of cortical response to sensory interference. We therefore hypothesized that odorants presented during sleep will increase power in slow EEG oscillations. Moreover, given that odorants do not drive sleep interruption, we hypothesized that unlike other sensory stimuli odorants would not drive K-complexes. To test these hypotheses we used polysomnography to measure sleep in 34 healthy subjects (19 F, mean age 26.5±2.5 years) who were repeatedly presented with odor stimuli via a computer-controlled air-dilution olfactometer over the course of a single-night. Each participant was exposed to one of four odorants: lavender oil (n=13), vetiver oil (n=5), vanillin, (n=12) or ammonium sulfide (n=4), for durations of 5, 10 and 20 seconds every 9-15 minutes. Consistent with our hypotheses, we found that odor presentation during sleep enhanced the power of delta (0.5-4 Hz) and slow spindle (9-12 Hz) frequencies during non-rapid eye movement (NREM) sleep. The increase was proportionate to odor duration. In addition, odor presentation did not modulate the occurrence of KCs. These findings imply a sleep-promoting olfactory mechanism that may deepen sleep through driving increased slow frequency oscillations.
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Résumé Il existe une abondante littérature, depuis plusieurs décennies, sur les liens entre olfaction et dépression. La revue de la littérature proposée ici n’a donc pas vocation à être exhaustive sur les travaux publiés mais vise plutôt à mettre en exergue les études les plus récentes et leurs apports à la compréhension des mécanismes olfactifs dans la dépression. En effet, étant donné l’existence de connexions étroites entre voies olfactives et aires cérébrales impliquées dans la régulation de l’humeur et des émotions (notamment au niveau du système limbique et des aires préfrontales), l’olfaction constitue une voie de recherche intéressante et novatrice à de nombreux égards. En premier lieu, l’étude des troubles olfactifs occurrents dans la dépression peut aider au diagnostic et surtout à la compréhension des mécanismes sous-jacents aux troubles thymiques. Les travaux publiés révèlent que l’épisode dépressif caractérisé est associé à une réduction de la sensibilité olfactive, ce qui n’est pas retrouvé dans la dépression bipolaire et la dépression saisonnière. En second lieu, il a été montré que des déficits de perception des odeurs pouvaient être à l’origine de symptômes dépressifs. Les corrélats neuro-anatomiques et neurochimiques plaident assez clairement pour un effet causal de la perte olfactive sur les troubles de l’humeur en général et, dans ce contexte, un modèle animal (rat bulbectomisé) conforte l’hypothèse du rôle non négligeable de l’olfaction dans les troubles dépressifs. En troisième lieu, plusieurs travaux tendent à prouver que les odeurs peuvent potentiellement avoir un impact sur l’amélioration des états dépressifs. Une remédiation par l’utilisation d’odeurs dans les troubles dépressifs et anxieux est une voie de recherche prometteuse, notamment du fait de l’impact sur le fonctionnement neurochimique de la dépression qui semble démontré chez l’animal.
Chapter
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As far as I know, the only reason we need to sleep that is really, really solid is because we get sleepy. Coming from William C. Dement, one of the pioneers of contemporary sleep research, this statement depicts sleep as a neurobiological black box. One of the best ways to probe such black boxes is through exceptions, and olfaction stands out as such an exceptional sensory system during sleep. Specifically, whereas sensory stimuli presented during sleep typically wake, this is not the case with odors. In fact, odors may promote sleep. In turn, they remain processed by the sleeping brain, and provide a telling window onto sleeping brain capabilities. Here, we briefly review the foundations of sleep, and then extensively detail the literature on olfaction in sleep, concentrating on studies in humans. We speculate that the unique interplay of sleep and smell whereby odors are processed in sleep without causing wake reflects unique aspects of olfactory neurophysiology, particularly the direct projections from periphery to cortex without a thalamic relay. Finally, although the mechanisms allowing odor processing during sleep without arousal remain unclear, this phenomenon lends itself to using olfaction as a window onto sleep mentation. This approach has uncovered several aspects of learning and memory during sleep. We review these efforts, and conclude with detailing their potential application in the treatment of disease.
Book
Human Behavior in Hazardous Situations introduces a new generation within safety management, fully developed with neuropsychological insights, developed in collaboration with, and put to test by, the chemical and process industries. Until now, there has been little theoretical framework on how, and especially why, people behave the way they do in hazardous situations. Human Behavior in Hazardous Situations presents new theories, based on a human behavioral approach, to offer a fresh perspective on safety management. By way of case studies, practical tips and exercises, Dr Jan Daalmans demonstrates how this neuropsychological approach can be applied for those safety managers working in the Chemical, Process and Pharmaceutical industries. Presents new brain-based approaches to safety, with a historical perspective on the evolution of the safety management. Practical tips and guidance for those working in the chemical and process industries. Including exercises and case studies to demonstrate the practical application of techniques.
Chapter
Aromas are becoming increasingly popular as a topic for scientific research. In this chapter, we review the available studies investigating whether and to which degree distinctive aromas promote cognitive enhancement. In general, it seems that arousing olfactory fragrances (e.g., peppermint) have an effect on memory, attention and cognitive control, whereas calming olfactory fragrances (e.g., lavender) seem to promote prosocial behavior and consumer behavior. We suggest that aromas may be a useful tool to promote cognitive enhancement, but in order to fully understand their mechanism of action more research is necessary.
Chapter
This study was designed to clarify whether the fragrance of peppermint oil has the effect of enhancing the concentration by using Psychomotor Vigilance Test (PVT). PVT was applied to the participants (n = 16, female) for 10 min in the room with peppermint oil and without the odor (control). The fragrance of peppermint was allowed to fill the room 10 min before the start of the measurement. The participants were asked to press a response button, located on the right side of the device, as soon as the visual stimuli appeared at random from 2 to 10 s in PVT. Visual Analogue Scale (VAS) was also used for subjective sensation (0, no concentrate at all; 100, concentrate very much). Reaction time (RT) to visual stimulation was measured for evaluation of concentration using PVT. Median of RT was significantly smaller in peppermint oil than that of control. Subjective sensation by VAS also showed significantly high concentration in peppermint oil compared with control. These results indicate that the concentration must increase by smelling the fragrance of peppermint oil. When people get tired during work, it suggests that concentration might improve by smelling the fragrance of peppermint followed by the prevention of human errors.
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Full-text available
Mentha piperita) ‫در‬ ‫شنای‬ ‫آزمون‬ ‫دم‬ ‫ماندن‬ ‫معلق‬ ‫آزمون‬ ‫و‬ ‫اجباری‬ ‫نر‬ ‫سوری‬ ‫موش‬ ‫در‬ ‫ملکی‬ ‫عباسی‬ ‫سعید‬ 1  ، ‫بختیاریان‬ ‫اعظم‬ 2 ‫نیکویی‬ ‫وحید‬ ، 3 1) ‫ایران‬ ،‫ارومیه‬ ،‫اسالمی‬ ‫آزاد‬ ‫دانشگاه‬ ،‫ارومیه‬ ‫واحد‬ ،‫شناسی‬ ‫سم‬ ‫و‬ ‫فارماکولوژی‬ ‫گروه‬ 2) ‫گروه‬ ‫ایران‬ ،‫تهران‬ ،‫تهران‬ ‫پزشکی‬ ‫علوم‬ ‫دانشگاه‬ ،‫فارماکولوژی‬ 3) ‫ایران‬ ،‫تهران‬ ،‫ایران‬ ‫پزشکی‬ ‫علوم‬ ‫دانشگاه‬ ،‫رازی‬ ‫دارویی‬ ‫تحقیقات‬ ‫مرکز‬ :‫دریافت‬ ‫تاریخ‬ 23 / 02 / 96 :‫پذیرش‬ ‫تاریخ‬ 18 / 04 / 96 TST .‫گردید‬ ‫بررسی‬ ‫نر‬ ‫سوری‬ ‫موش‬ ‫در‬) :‫ها‬ ‫روش‬ ‫و‬ ‫مواد‬ ‫د‬ ،‫تجربی‬ ‫مطالع‬ ‫این‬ ‫ر‬ 96 ‫ب‬ ‫تصادفی‬ ‫طور‬ ‫ب‬ ‫نر‬ ‫سوری‬ ‫موش‬ ‫سر‬ 12 ‫گروه‬ 8 ‫نرمال‬ ‫ترتیب‬ ‫ب‬ ‫و‬ ‫شده‬ ‫تقسیم‬ ‫تایی‬ (‫سالین‬ ml/kg 10 (‫پیرامین‬ ‫ایمی‬ ،) mg/kg 30 (‫فلوکستین‬ ،) mg/kg 20 (‫فلفلی‬ ‫نعنا‬ ‫مختلف‬ ‫دوزهای‬ ‫و‬) mg/kg 400 ‫و‬ 200 ، 100 ‫در‬ .‫نمودند‬ ‫دریافت‬ ‫را‬) ‫آزمون‬ FST ‫حرکتی‬ ‫بی‬ ‫زمان‬ ‫مدت‬ ، ‫آزمون‬ ‫در‬ ‫و‬ ‫کردن‬ ‫صعود‬ ‫و‬ ،‫کردن‬ ‫شنا‬ TST ‫طی‬ ‫در‬ ‫حیوان‬ ‫حرکتی‬ ‫بی‬ ‫زمان‬ ‫مدت‬ 6 ‫این‬ ‫در‬ .‫شدند‬ ‫ربت‬ ‫دقیق‬ ‫معیین‬ ‫حجم‬ ‫در‬ ‫و‬ ‫صفاقی‬ ‫داخل‬ ‫شکل‬ ‫ب‬ ‫ها‬ ‫عصاره‬ ‫و‬ ‫داروها‬ ‫تمام‬ ‫بررسی‬ ml/kg 10 .‫شدند‬ ‫تزریق‬ ‫يافته‬ :‫پژوهش‬ ‫های‬ ‫دوزهای‬ ‫ک‬ ‫داد‬ ‫نشان‬ ‫نتایج‬ mg/kg 200 ‫و‬ 400 ‫پیرامین‬ ‫ایمی‬ ،‫عصاره‬ ‫فلوکست‬ ‫و‬ ‫ههه‬ ‫زم‬ ‫مدت‬ ‫ین‬ ‫هه‬ ‫حرکتی‬ ‫بی‬ ‫ان‬ ‫در‬ ‫را‬ ‫های‬ ‫آزمون‬ FST ‫و‬ TST ‫دادند‬ ‫کاهش‬ (P<0.001) ‫هم‬. ‫کردن‬ ‫شنا‬ ‫زمان‬ ‫مدت‬ ‫افزایش‬ ‫سبب‬ ‫فلوکستین‬ ‫و‬ ‫اتانولی‬ ‫عصاره‬ ،‫چنین‬ (P<0.001) ‫تغییر‬ ‫بدون‬ ‫کردن‬ ‫صعود‬ ‫زمان‬ ‫در‬ ‫دار‬ ‫معنی‬ ‫گردیدند‬ (P>0.05) ‫کردن‬ ‫صعود‬ ‫افزایش‬ ‫باعث‬ ‫پیرامین‬ ‫ایمی‬ ، ‫مقایس‬ ‫در‬. (P<0.001) ‫کردن‬ ‫شنا‬ ‫در‬ ‫دار‬ ‫معنی‬ ‫تغییر‬ ‫بدون‬ ‫شد‬ (P>0.05) .
Article
Objective This study aims to quantify the impact of olfactory stimulation and takeover modality on the performance of takeovers in conditionally automated driving. Background Takeover requests are important for the safety of automated vehicles. The reaction time and subsequent performance of drivers in the takeover process are crucial for safety. In this study, peppermint was adopted as an auxiliary modality to the tactile and auditory design of takeover requests. Methods Sixty participants took part in the experiment, which required participants to avoid a stalled vehicle after they were awoken from a state of light sleep by a takeover request. Takeover modality (tactile, auditory, and combined) was the within-subjects factor. In the between-subjects design, half of the participants received a peppermint odor stimulation when the takeover request occurred, and the other half received a placebo (air). Results The presence of peppermint odor did not influence the reaction time, but participants did show signs of being more alert afterwards. For the moment of takeover, use of the auditory modality had a significant positive effect on reaction time compared to the tactile conditions. Conclusion Peppermint odor had a positive impact on drivers’ takeover quality when engaged in nondriving-related activities such as light sleep, and the takeover request modalities were shown to be crucial for a safe and successful takeover. Application The results will be useful as a reference for developers of automated driving systems to design human–machine interfaces, shorten the driver’s reaction time, and improve takeover quality.
Article
Alzheimer's disease (AD) provides a valuable field of research into impairment of self-consciousness (SC), because AD patients have a reduced capacity to understand their mental world, to experience and relive previous personal events, as well as to interpret thoughts, feelings, and beliefs about themselves. Several studies observed that AD patients had an altered SC, but not a complete abolition of it. Emotions are an integral part of the construction of personal identity, therefore of Self. In general, most studies on emotion in AD patients have observed that emotion is not completely abolished and it lets them better remember autobiographical events with greater emotional charge. The positive effect of autobiographical memories rich in emotional content, evoked directly/automatically by sensorial stimuli such as familiar odors or music, could be used to reestablish/reinforce the permanence and coherence of the Self in AD. We studied the research of empirical evidence supporting the power of the sensorial cues associated with emotion, which could be capable of enhancing the SC in AD. We presented the studies about "Emotional stimulations" using odor, music, or taste cues in AD. All studies have shown to have a positive impact on SC in AD patients such as odor-evoked autobiographical memories, taste/odor-evoked autobiographical memories, emotional sensorial stimulation using musical cues, and multi-sensorial stimulations using healing gardens. We found research supporting the notion that emotional sensorial stimulations can even temporarily exalt memory, affective state, and personal identity, that is, the SC in AD. The emotional sensory stimulations could be used as a tool to activate the SC in AD and hence improve the quality of life of patients and caregivers.
Article
The notion that chewing gum may relieve stress was investigated in a controlled setting. A multi-tasking framework which reliably evokes stress and also includes performance measures was used to induce acute stress in the laboratory. Using a randomised crossover design forty participants (mean age 21.98 years) performed on the multi-tasking framework at two intensities (on separate days) both while chewing and not chewing. Order of workload intensity and chewing conditions were counterbalanced. Before and after undergoing the platform participants completed the state portion of the State-Trait Anxiety Inventory, Bond-Lader visual analogue mood scales, a single Stress Visual Analogue Scale and provided saliva samples for cortisol measurement. Baseline measures showed that both levels of the multi-tasking framework were effective in significantly reducing self-rated alertness, calmness and contentment while increasing self-rated stress and state anxiety. Cortisol levels fell during both levels of the stressor during the morning, reflecting the predominance of a.m. diurnal changes, but this effect was reversed in the afternoon which may reflect a measurable stress response. Pre-post stressor changes (Delta) for each measure at baseline were subtracted from Delta scores under chewing and no chewing conditions. During both levels of stress the chewing gum condition was associated with significantly better alertness and reduced state anxiety, stress and salivary cortisol. Overall performance on the framework was also significantly better in the chewing condition. The mechanisms underlying these effects are unknown but may involve improved cerebral blood flow and/or effects secondary to performance improvement during gum chewing.
Article
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Synopsis Subjects performed a visual sustained attention (vigilance) task for 40 minutes during which they received periodic 30-second whiffs of pure air or a hedonically positive fragrance, Muguet or Peppermint, through a modified oxygen mask. The former fragrance had been independently judged as relaxing, the latter as alerting. Subjects receiving either fragrance detected significantly more signals during the vigil than unscented air controls. Subjective reports of mood and workload indicated that the subjects experienced the vigilance task as stressful and demanding. However, the fragrances had no impact on the latter measures. These results provide the initial experimental evidence to indicate that fragrances can enhance signal detectability in a task demanding sustained attention, though the exact characteristics of effective fragrances have yet to be determined.
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The present study examined the effect of an alerting and a relaxing odour on human visual vigilance. Three groups of undergraduates (N = 54) completed a sustained visual vigilance task which required them to respond whenever a target stimulus appeared on a computer monitor. One group completed the task in the presence of an alerting odour (peppermint), another did so in the presence of a relaxing odour (bergamot) and a third group completed the task in an unscented environment. A 2×3×2 (sex×odour×diurnal preference) MANOVA was performed in order to determine group differences in response times and number of correct detections. Participants in the bergamot condition detected fewer targets correctly within 1.25 seconds of the target appearing than did those in the peppermint or no-odour groups. Exposure to bergamot was also associated with significantly fewer correct detections in the second than in the first half of the task, when compared with the other two conditions. The results suggest that sustained exposure to a relaxing odour can impair visual vigilance. Copyright © 2001 John Wiley & Sons, Ltd.
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The perceptional change of fragrance of essential oils is described in relation to type of work, i.e. mental work, physical work and hearing environmental (natural) sounds. The essential oils examined in this study were ylang ylang, orange, geranium, cypress, bergamot, spearmint and juniper. In evaluating change in perception of a given aroma, a sensory test was employed in which the perception of fragrance was assessed by 13 contrasting pairs of adjectives. Scores were recorded after inhaling a fragrance before and after each type of work, and the statistical significance of the change of score for 13 impression descriptors was examined by Student's t-test for each type of work. It was confirmed that inhalation of essential oil caused a different subjective perception of fragrance depending on the type of work. For example, inhalation of cypress after physical work produced a much more favorable impression than before work, in contrast to orange, which produced an unfavorable impression after physical work when compared with that before work. For mental work, inhalation of juniper seemed to create a favorable impression after work, whereas geranium and orange both produced an unfavorable impression then. From these studies, together with those conducted previously with lavender, rosemary, linalool, peppermint, marjoram, cardamom, sandalwood, basil and lime, we thus concluded that the sensory test described here might serve not only as a screening test for efficacy of aroma but also as a categorized table for aroma samples which can act as a reference to each other.
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Scientific research on the effects of essential oils on human behavior lags behind the promises made by popular aromatherapy. Nearly all aspects of human behavior are closely linked to processes of attention, the basic level being that of alertness, which ranges from sleep to wakefulness. In our study we measured the influence of essential oils and components of essential oils [peppermint, jasmine, ylang-ylang, 1,8-cineole (in two different dosages) and menthol] on this core attentional function, which can be experimentally defined as speed of information processing. Substances were administered by inhalation; levels of alertness were assessed by measuring motor and reaction times in a reaction time paradigm. The performances of the six experimental groups receiving substances (n = 20 in four groups, n = 30 in two groups) were compared with those of corresponding control groups receiving water. Between-group analysis, i.e. comparisons between experimental groups and their respective control groups, mainly did not reach statistical significance. However, within-group analysis showed complex correlations between subjective evaluations of substances and objective performance, indicating that effects of essentials oils or their components on basic forms of attentional behavior are mainly psychological.
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The effects on humans inhaling the fragrance of essential oils were examined in terms of a sensory test, a multi-channel skin thermometer study and a portable forehead surface electroencephalographic (IBVA-EEG) measurement. The essential oils examined in this study were those of basil and peppermint, because our previous sensory test had indicated an opposite effect of these essential oils when mental work was undertaken; the inhalation of basil produced a more favorable impression after work than before work, whereas peppermint produced an unfavorable impression under these circumstances. For subjects administered basil or peppermint before and after mental work using an inhalator, a series of multi-channel skin thermometer studies and IBVA-EEG measurements were conducted. Using such paired odorants, our results showed that when compared between before and after mental work assigned to subjects: (1) the inhalation of basil, in which a favorable impression was predominant on the whole in terms of the sensory evaluation spectrum, was shown to be associated upward tendency in finger-tip skin temperature; (2) whereas these situations were opposite in the case of peppermint, in which the reversed (unfavorable) feature in sensory profiling was accompanied by a decrease in the magnitude of beta waves and a decrease in the finger-tip skin temperature both based on Welch's method, even at p < 0.01, implying a decreasing propensity of the aroused state and of the arousal response. The elucidation of such sensory and physiological endpoints of paired odorants would be of primary importance for human chemoreception science, because these are only rarely recorded during the same experiments, and this paradigm is highly informative about non-verbal responses to odorants.
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This article examines the statistical determinants of risk preference. In a meta-analysis of animal risk preference (foraging birds and insects), the coefficient of variation (CV), a measure of risk per unit of return, predicts choices far better than outcome variance, the risk measure of normative models. In a meta-analysis of human risk preference, the superiority of the CV over variance in predicting risk taking is not as strong. Two experiments show that people's risk sensitivity becomes strongly proportional to the CV when they learn about choice alternatives like other animals, by experiential sampling over time. Experience-based choices differ from choices when outcomes and probabilities are numerically described. Zipf's law as an ecological regularity and Weber's law as a psychological regularity may give rise to the CV as a measure of risk.
Chapter
There have been several attempts to measure objectively the psychological effects of odours (Dodd and Van Toller, 1983), but as yet no electrical brain wave responses to odours have been confirmed (Allison and Goff, 1967; Pattig and Kobal, 1979; Tonoike and Kurioka, 1982). In this chapter we will look at the psychological effect of odours on brain activity. We will concentrate on odours that are stimulating or sedative.
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Previous research has indicated that odorant presentations can have both positive and negative effects on psychological perceptions of athletic task performance. The present study extends past research by assessing how the administration of peppermint odor affects actual athletic task performance. Forty athletes undertook a series of physical tasks under conditions of no-odor or peppermint odor. The peppermint odor condition resulted in increases in running speed, hand grip strength, and number of push-ups, but had no effect on skill related tasks such as basketball free-throw shots. The implications are particularly salient in regard to enhancing athletic performance using a nonpharmacological aid and as an adjunct to athletic training and physical therapy.
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Two techniques are described which allow the simultaneous measurement of pupil size and the corresponding two-dimensional movements of the eyes. The techniques are based on algorithms for the extraction of the diameter of the pupil and the spatial coordinates of its centre, from intersection points between the circumference of the pupil and a specified pattern of lines. The first method uses a grid of horizontal lines and results in high measurement accuracy. The second method which makes use of two orthogonal lines is much faster, but is also less accurate. A system based on the first method has been constructed and allows binocular or dichoptic stimulation and measurement of both pupil size and the two-dimensional movements of the eyes. Appropriate software has been developed for automatic extraction of principal parameters from both eye-movement and pupilometric data. The algorithms which are used to extract the parameters of interest yield accurate measurements with a typical resolution of 2 min of arc for eye-movements and better than 0.01 mm for the measurement of pupil size. The extremely high resolution achieved in such measurements is due partly to the statistical properties of the algorithm used for locating a circular aperture on a grid of horizontal lines. The system is easy to calibrate for both pupil size and eye-movement measurements. Results of preliminary experiments suggest that stimulus-evoked activity in the central visual pathways gives rise to small, stimulus-specific pupillary responses.
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The perceptional change of fragrance of essential oils is described in relation to type of work, i.e. mental work, physical work and hearing environmental (natural) sounds. The essential oils examined in this study were ylang ylang, orange, geranium, cypress, bergamot, spearmint and juniper. In evaluating change in perception of a given aroma, a sensory test was employed in which the perception of fragrance was assessed by 13 contrasting pairs of adjectives. Scores were recorded after inhaling a fragrance before and after each type of work, and the statistical significance of the change of score for 13 impression descriptors was examined by Student’s t-test for each type of work. It was confirmed that inhalation of essential oil caused a different subjective perception of fragrance depending on the type of work. For example, inhalation of cypress after physical work produced a much more favorable impression than before work, in contrast to orange, which produced an unfavorable impression after physical work when compared with that before work. For mental work, inhalation of juniper seemed to create a favorable impression after work, whereas geranium and orange both produced an unfavorable impression then. From these studies, together with those conducted previously with lavender, rosemary, linalool, peppermint, marjoram, cardamom, sandalwood, basil and lime, we thus concluded that the sensory test described here might serve not only as a screening test for efficacy of aroma but also as a categorized table for aroma samples which can act as a reference to each other.
Article
Scientific research on the effects of essential oils on human behavior lags behind the promises made by popular aromatherapy. Nearly all aspects of human behavior are closely linked to processes of attention, the basic level being that of alertness, which ranges from sleep to wakefulness. In our study we measured the influence of essential oils and components of essential oils [peppermint, jasmine, ylang-ylang, 1,8-cineole (in two different dosages) and menthol] on this core attentional function, which can be experimentally defined as speed of information processing. Substances were administered by inhalation; levels of alertness were assessed by measuring motor and reaction times in a reaction time paradigm. The performances of the six experimental groups receiving substances (n = 20 in four groups, n = 30 in two groups) were compared with those of corresponding control groups receiving water. Between-group analysis, i.e. comparisons between experimental groups and their respective control groups, mainly did not reach statistical significance. However, within-group analysis showed complex correlations between subjective evaluations of substances and objective performance, indicating that effects of essentials oils or their components on basic forms of attentional behavior are mainly psychological.
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Whilst many previous studies have reported the effects of individual variables on odour perception, very little work has been reported which identifies the contribution of each of these variables to the odour experience. Few investigators have considered how these different factors are related to one another. It is unclear, at this stage, whether indirect effects such as expectations, beliefs, and personality are interactive or whether there is a single factor underpinning all psychological factors.How then, is this of interest to aromatherapists? In the first instance, professional aromatherapists should be aware of how essential oils influence the individual they are treating. If it becomes evident that the application of essential oils to a client results in direct physiological changes then one needs to identify which oils will be suitable for the particular application required. This would provide a rather strict framework from which aromatherapists should work. However, should it be found that the effects of essential oils are largely indirect, or cognitive, by nature, then a much more relaxed structure of which oils are suitable could be employed. This would allow the aromatherapist to “negotiate” which oils a particular client would like used during their treatment. The future is uncertain at the moment, however from the evidence discussed in this article, it is likely that both direct and indirect effects influence how a particular essential oil will perform.
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The side of the nose having the greater sensitivity for the detection of n-butanol was determined for 19 male subjects (nine left-handed and ten right-handed) using a two-interval forced choice paradigm and a flow dilution olfactometer. These determinations showed not only that the subjects did have a nostril of greater sensitivity but that left- and right-handed subjects significantly differed in the side of that greater sensitivity: Left-handed subjects were very consistent in showing greater sensitivity in the left side of the nose, whereas right-handed subjects showed a weak tendency toward greater sensitivity in the right side of the nose. A number of physiological and anatomical explanations are offered to account for these results, but it is felt that there is now enough evidence for a relationship between handedness and nasal side sensitivity, for whatever reason, to merit its further consideration.
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The purpose of the present study was to examine the relationship among the Multiple Sleep Latency Test (MSLT), lapses during a tapping task, a visual analog scale (VAS) and the Stanford sleepiness scale (SSS). Subjects were 80 male adult nonsmokers (age 20.3 + or - 2.7 years). The MSLT, SSS, and the VAS were obtained at two-hour intervals beginning at 0700 h. On the MSLT, sleep latency was measured from lights out to first spindle, K-complex or rapid-eye- movement (REM) period. The tapping task (lapses) was administered each day at 0600 h, but became nonsignificant as the day progressed. Correlations of objective and subjective measures from scores summed over both days were not significant. The two objective measures were significantly correlated throughout the day and over days as were the subjective measures. This study reaffirms the importance of time of day in sleepiness, and suggests that subjective and objective measures cannot be used interchangeably and may measure different aspects of sleepiness.
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Two experiments examined the relationship between time domain patterns of EEG activity and self-reports for individuals exposed to different odorants. In Exp 1, 3 odorants produced different patterns of EEG theta activity and self reports from 9 adults, suggesting that odor administration is a reliable variable in manipulating neurophysiological response systems and may influence performance and mood. In Exp 2, EEG activity was recorded while 10 adults smelled 5 similar commercial odorous chemicals and an unscented base. Ss also completed questionnaires on odor character and mood. Results indicate that few perceptual or mood differences were produced by the odors. EEG alpha and theta activity in the left and right hemispheres, however, differed depending upon the odor presented and was dissociated from self-reports. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Article
In two sessions held 1 week apart, subjects completed a performance task involving creativity, four personality tests, and questionnaires concerning their mood, perceived health, and perceptions of the testing environment. In one session the testing room was scented with lemon, lavender or dimethyl sulfide (DMS); in the other session it was unscented. There were 15 women and 15 men in each odor conditon. Fewer health symptoms were reported in the lemon conditon on scented compared to unscented days. Subjects in the DMS group were in a less pleasant mood than those in the lavender group on both scented and unscented days; the order in which subjects were exposed to DMS played a role in the mood findings. There were no significant differences in feelings of arousal or control. The room was rated as smelling less pleasant on scented compared to unscented days by subjects in the DMS condition. Differences in creativity performance were not significant, but relationships emerged between personality traits and the effect of odor on task performance. These findings are discussed in terms of how associations and expectations concerning odors may play a role in odor's effect on humans.
Article
Whether humans react to olfactory stimuli presented in sleep was assessed. Responses of ten participants (mean age = 22.8 years) were recorded to repeated three-minute periods of either air alone or to a peppermint odor (0.26 mg/liter) during stage 2 sleep. These responses included behavioral (awakening, microswitch closure), autonomic (heart rate, EMG, respiration), and central (EEG) components. An odor delivery system is described comprised of an aquarium pump, Teflon and TYGON tubing, oxygen mask, filtering, and air flow valves. The data indicate that humans react behaviorally, autonomically and centrally to olfactory stimuli presented while sleeping. Although the percentage of overall responsivity to olfactory stimuli was low, significant differences (ANOVA) in responsivity to odor periods vs. nonodor periods were found for microswitch closures, EEG, EMG, and heart rate. For these measures eight or more of the ten participants showed this pattern of differential responsivity during odor and nonodor periods (Sign test = p less than 0.05). A time-of-night effect was also observed in that responsivity tended to be greatest early in the night. The effect on responsivity of other durations, concentrations, and odors requires additional research.
Article
Investigated whether the Stanford Sleepiness Scale (SSS), a self-rating scale used to quantify progressive steps in sleepiness, cross-validates with performance on mental tasks and whether the SSS demonstrates changes in sleepiness with sleep loss. 5 undergraduates were given a brief test of memory and the Wilkinson Addition Test in 2 test sessions and the Wilkinson Vigilance Test in 2 other sessions spaced throughout a 16-hr day for 6 days. Ss made SSS ratings every 15 min during their waking activities. On Night 4, Ss underwent all-night sleep deprivation. On all other nights, Ss were allowed only 8 hrs in bed. Mean SSS ratings correlated r = .68 with performance on the Wilkinson tests. Discrete SSS ratings correlated r = .47 with performance on the memory test. Moreover, mean baseline SSS ratings were found to be significantly lower than corresponding ratings of the deprivation period. (PsycINFO Database Record (c) 2005 APA, all rights reserved)
Article
In 19 normal subjects the pupillary reflex to light was studied over a range of stimulus intensities by infrared electronic pupillography and analysed by a computer technique. Increasing stimulus intensity was associated with an increase in direct light reflex amplitude and maximum rate of constriction and redilatation. Latency from stimulus to onset of response-decreased with increasing stimulus intensity. The normal range for each of these parameters is given and the significance of these results in clinical pupillary assessment discussed.
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Spontaneous pupillary-behavior in darkness provides information about a subject's level of sleepiness. In the present work, pupil measurements in complete darkness and quiet have been recorded continuously over 11-minute period with infrared video pupillography at 25 Hz. The data have been analyzed to yield three parameters describing pupil behavior; the power of diameter variation at frequencies below 0.8 Hz (slow changes in pupil size), the pupillary unrest index, and the average pupil size. To investigate the changes of these parameters in sleep deprivation, spontaneous pupillary behavior in darkness was recorded every 2 hours in 13 healthy subjects from 19:00 to 07:00 during forced wakefulness. On each occasion, comparative subjective sleepiness was assessed with a self-rating scale (Stanford Sleepiness Scale, SSS). The power of slow pupillary oscillations (< or = 0.8 Hz) increased significantly and so did the values of SSS, while basic pupil diameter decreased significantly. Slow pupillary oscillations and SSS did not correlate well in general but high values of pupil parameters were always associated with high values in subjective rating. Our results demonstrate a strong relationship between ongoing sleep deprivation and typical changes in the frequency profiles of spontaneous pupillary oscillations and the tendency to instability in pupil size in normals. These findings suggest that the results of pupil data analysis permit an objective measurement of sleepiness.
Article
Spontaneous pupillary behaviour in darkness provides information about a subject's level of vigilance. To establish infrared video pupillography (IVP) as a reliable and objective test in the detection and quantification of daytime sleepiness, the definition of numerical parameters is an important precondition characterising spontaneous pupil behaviour adequately for further statistical procedures. The correct measurement of the pupil size, even if the lid or eyelashes are occluding the pupil, is of particular concern when testing vigilance. In this case many edge points of the pupil are detected and a fitting procedure is described that fits these edge points to a circle and excludes outliers. The first step of data preparation consists of a mathematical artefact management consisting of blink detection and elimination, followed by interpolation. Second, a fast Fourier transformation is carried out for frequencies from 0.0 to 0.8 Hz for each time segment of 82 s. Results are given in absolute and relative power of each frequency band per time segment and mean values over the entire record of 11 min. Third, the changes of the mean pupillary diameter per data window against time are shown graphically. An additional parameter referring to the pupil's tendency to instability, the pupillary unrest index (PUI), is defined by cumulative changes in pupil size based on mean values of consecutive data sequences. These mathematical procedures provide a high level of quality in both data collection and evaluation of IVP as an objective test of vigilance. In a pilot study, the pupillary behaviour of two groups were measured. One group rated themselves as alert (ten men), the other group as sleepy (12 men). The power and PUI were compared using the Mann-Whitney U-test. Both parameters show significant differences between the two groups.
Article
Pupillary oscillations in darkness are considered to be a sign of sleepiness. The purpose of this pilot study was to ascertain whether pupillary oscillations were more pronounced in patients with hypersomnia than in normals. Seven patients (four with sleep apnea syndrome, three with narcolepsy) and seven age-matched controls underwent pupillography for 11 min in complete darkness. The changes in pupil size were analyzed mathematically to determine quantitatively the amount of pupillary instability. Hypersomniacs had much higher amounts of pupillary oscillations in darkness than normals. The differences were significant. Baseline pupil size did not differ significantly between the two groups. This study showed that a pupillographic sleepiness test based on the evaluation of spontaneous pupillary changes in darkness is applicable in hypersomniacs and may facilitate therapy control, i.e. diagnostic grading by measuring daytime sleepiness objectively.
Article
Pupil size is regulated exclusively by the autonomic nervous system, and in darkness is proportional to the level of central sympathetic tone. Spontaneous pupillary movements, while at rest in darkness and quiet, were recorded for a period of 11 min, using infrared video pupillography. Thirteen young adults took part in a 30-h experiment lasting from 08.00 h to 14.00 h on the following day. Pupillographic testing and completion of a self-rated scale for the estimate of sleepiness were repeated every two hours. Pupillary unrest index (PUI), as a measure of pupil size instability associated with daytime sleepiness, showed the lowest values at 09.00 h, when pupil size was found to be maximal, and 23.00 h. During the course of the day, amplitude spectrum < or = 0.8 Hz and PUI showed increasing values during the afternoon hours, followed by a decrease during the evening. Daytime variations in the pupillary unrest index in healthy normal subjects were found to be positively correlated with the level of alertness. These findings are similar to the daytime variations found by the MSLT (multiple sleep latency test) in young adults.
Article
The aim of the present study is to analyze how well physiological measures of sleepiness derived from pupillography and the Multiple Sleep Latency Test correlate with a subjective measure, the Stanford Sleepiness Scale (SSS) score. The results are based on data from 12 healthy participants, who underwent these tests every 2 hr from 7:00 a.m. until 11:00 p.m. Sleep latencies were correlated with four different variables derived from pupillography and the SSS score. The results indicate that the physiologically based variables correspond very well. This is reflected by similar patterns of time-of-day variations, a good agreement at the group level, and correlations at the individual level, whereas the SSS shows a quite different pattern of variation. The two physiological measures of sleepiness seem to reflect the same aspect of the level of tonic central nervous activation, which is not correlated with the subjective feeling of sleepiness.
Article
Clinical aromatherapy is the use of essential oils for expected outcomes that are measurable and is a therapy that is used as part of nursing care in Switzerland, Germany, Australia, Canada, the United Kingdom, and, more recently, the United States. Essential oils are steam distillates obtained from aromatic plants. These volatile extracts have been used for many years by French hospitals against airborne bacteria and fungi. As antimicrobial agents, essential oils may be appropriate in HIV/AIDS for specific opportunistic infections. Aromatherapy can also alter perceptions of chronic pain, help maintain skin integrity, and is useful in stress management. Methods of application vary depending on the site of infection and the psychological profile of the patient and can include inhalation, compresses, baths, massage, and the "m" technique. This article will explore the potential use of essential oils in HIV/AIDS focusing on four opportunistic infections: Cryptococcus neoformans, Candida albicans, methicillin-resistant Staphylococcus aureus, and herpes simplex types I and II.
Article
Basic models of sleepiness, focusing on the homeostatic and circadian components of sleepiness, are able to predict important fluctuations of sleepiness. However, they fail in explaining certain sleepiness phenomena, as for instance in insomnia patients. To meet this shortcoming, modern models incorporate the arousal component of sleepiness, in addition to the sleep drive. While these models mainly concentrate on short-term changes in sleepiness, "state" sleepiness, there are indications that a stable characteristic level of sleepiness, "trait" sleepiness, is also an important determinant of a person's level of sleepiness. This leads to a conceptualization of sleepiness in which situational factors modify a basal level of sleep drive and arousal. It implies that sleepiness is not a unitary concept and can reflect essentially different states. Multiple sleepiness assessment tools have been proposed in the past. The majority of them offer valuable information, but they do not grasp all aspects of sleepiness. We should bear in mind that tools for assessing sleepiness are always operationalizations reflecting the theoretical framework the investigator has on sleepiness. Hence, rather than searching for a gold standard for the measurement of sleepiness, future research effort should be aimed at linking the various measurement techniques with the hypothesized underlying components of sleepiness on a sound empirical basis.
Article
Investigators have suggested using pupillometry to assess alertness in hypersomnolent patients. In this study we assessed hypersomnolent patients and normal volunteers by using pupillometry and examined the usefulness of this technique for the diagnosis of pathologic sleepiness in individual patients. Forty-nine patients were examined by pupillometry and their sleepiness was assessed by using the multiple sleep latency test (MSLT). Thirty-three normal well-rested volunteers were also examined by pupillometry. The patients were classified as having 'mild', 'moderate', or 'severe' sleepiness, based on their mean MSLT sleep latency. Several dynamic variables of pupil diameter were calculated from the pupillograms and correlated with the mean MSLT sleep latency, and were compared between severity groups of patients and the well-rested normal subjects. All but two pupillometric variables were significantly correlated with sleep latency. All except the same two pupillometric variables of the sleepiest group were significantly different from those of normal subjects. However, only 51% of patients with mean sleep latencies less than 10 min and 35% of patients with mean sleep latencies of less than 5 min could be correctly identified by pupillometry. Pupillometry is clearly associated with differences in alertness between groups of patients. However, pupillometric assessment cannot substitute for the MSLT in most cases.
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