Linking Categorical and Dimensional Approaches to Assess Food-Related Emotions.

Reflecting the two main prevailing and opposing views on the nature of emotions, emotional responses to food and beverages are typically measured using either (a) a categorical (lexicon-based) approach where users select or rate the terms that best express their food-related feelings or (b) a dimensional approach where they rate perceived food items along the dimensions of valence and arousal. Relating these two approaches is problematic since a response in terms of valence and arousal is not easily expressed in terms of emotions (like happy or disgusted). In this study, we linked the dimensional approach to a categorical approach by establishing mapping between a set of 25 emotion terms (EsSense25) and the valence-arousal space (via the EmojiGrid graphical response tool), using a set of 20 food images. In two 'matching' tasks, the participants first imagined how the food shown in a given image would make them feel and then reported either the emotional terms or the combination of valence and arousal that best described their feelings. In two labeling tasks, the participants first imagined experiencing a given emotion term and then they selected either the foods (images) that appeared capable to elicit that feeling or reported the combination of valence and arousal that best reflected that feeling. By combining (1) the mapping between the emotion terms and the food images with (2) the mapping of the food images to the valence-arousal space, we established (3) an indirect (via the images) mapping of the emotion terms to the valence-arousal space. The results show that the mapping between terms and images was reliable and that the linkages have straightforward and meaningful interpretations. The valence and arousal values that were assigned to the emotion terms through indirect mapping to the valence-arousal space were typically less extreme than those that were assigned through direct mapping.

Exploring impact on eating behaviour, exercise and well-being during COVID-19 restrictions in the Netherlands.

Many studies address the effect of the COVID-19 restrictions on food consumption and health, focusing on one or two measurements. Whether or not any effects are permanent or change over a longer period of restrictions has not been assessed in such studies. This study presented a survey containing questions on food consumption, exercise and self-assessed physical and mental health, repeatedly for six times over a 20-week period (July to November 2020) to a representative sample of 258 Dutch consumers. The majority of consumers reported no change in food consumption compared to before the COVID-19 restrictions, two smaller groups report a change to a more, or a less, healthy choice. This trend appears stable over the course of the measurements. The 'healthy changers' seem to couple a healthy and more diverse diet to healthy exercise habits, in contrast to the 'unhealthy changers'. No change was observed in self-assessed physical health over the measurements. Overall a decline in time spent exercising showed, as well as a decline in self-assessed mental health. Clearly a lockdown situation affects food choice, exercise habits and (self-assessed) mental health. The fact that habits are able to suddenly change, for better or for worse, and that a decrease in mental health was reported, suggests that such insights need to be further explored to help individual consumers retain a healthy diet and lifestyle, and governments devise effective public health recommendations.

Reading Food Experiences from the Face: Effects of Familiarity and Branding of Soy Sauce on Facial Expressions and Video-Based RPPG Heart Rate.

Food experiences are not only driven by the food's intrinsic properties, such as its taste, texture, and aroma, but also by extrinsic properties such as visual brand information and the consumers' previous experiences with the foods. Recent developments in automated facial expression analysis and heart rate detection based on skin color changes (remote photoplethysmography or RPPG) allow for the monitoring of food experiences based on video images of the face. RPPG offers the possibility of large-scale non-laboratory and web-based testing of food products. In this study, results from the video-based analysis were compared to the more conventional tests (scores of valence and arousal using Emojis and photoplethysmography heart rate (PPG)). Forty participants with varying degrees of familiarity with soy sauce were presented with samples of rice and three commercial soy sauces with and without brand information. The results showed that (1) liking and arousal were affected primarily by the specific tastes, but not by branding and familiarity. In contrast, facial expressions were affected by branding and familiarity, and to a lesser degree by specific tastes. (2) RPPG heart rate and PPG both showed effects of branding and familiarity. However, RPPG heart rate needs further development because it underestimated the heart rate compared to PPG and was less sensitive to changes over time and with activity (viewing of brand information and tasting). In conclusion, this study suggests that recording of facial expressions and heart rates may no longer be limited to laboratories but can be done remotely using video images, which offers opportunities for large-scale testing in consumer science.

Measuring Implicit Approach-Avoidance Tendencies towards Food Using a Mobile Phone outside the Lab.

Implicit ('unconscious') approach-avoidance tendencies towards stimuli can be measured using the Approach Avoidance Task (AAT). We recently expanded a toolbox for analyzing the raw data of a novel, mobile version of the AAT (mAAT), that asks participants to move their phone towards their face (pull) or away (push) in response to images presented on the phone. We here tested the mAAT reaction time and the mAAT distance in a study with 71 Dutch participants that were recruited online and performed an experiment without coming to the laboratory. The participants used both the mAAT and (explicit) rating scales to respond to photographic images of food. As hypothesized, the rated wanting, rated valence and mAAT reaction time indicated a preference for palatable over unpalatable food, and for Dutch over Asian food. Additionally, as expected, arousal was rated higher for unpalatable than for palatable food, and higher for Dutch than for Asian food. The mAAT distance indicated that the unpalatable food images were moved across larger distances, regardless of the movement direction (pull or push), compared to the palatable food images; and the Dutch food images were moved across larger distances than the Asian food images. We conclude that the mAAT can be used to implicitly probe approach-avoidance motivation for complex images in the food domain. The new measure of mAAT distance may be used as an implicit measure of arousal. The ratings and the mAAT measures do not reflect the exact same information and may complement each other. Implicit measures, such as mAAT variables, are particularly valuable when response biases that can occur when using explicit ratings are expected.

Some insights into the development of food and brand familiarity: The case of soy sauce in the Netherlands.

With the increasing globalization, new unfamiliar flavors gradually find their way into local Western cuisines. The mechanisms behind the successful integration of novel flavors into local cuisines are largely unknown. This study investigates the effects of frequency of soy sauce use, levels of food neophobia, and brand specificity on liking of a relatively unknown flavor in the Netherlands, soy sauce. A total of eighty-nine (26 men and 63 women; mean age 47.5 ± 17.7 years) high- and low-frequency users of soy sauce rated liking of five soy sauces separately presented with and without branding information. Liking of four soy sauces with the typical salty and savory flavor increased with increasing frequency of use, and with decreasing levels of food neophobia. Another soy sauce with additives resulting in a distinctive taste was liked irrespective of the frequency of use. Soy sauces, which were recognized correctly or incorrectly as the participants' own familiar brand, received 50% higher or lower liking ratings than other soy sauces, respectively. Furthermore, users of one of the brands preferred the taste of their own brand over that of other brands, whereas users of the other brands did not show such specificity, indicating clear differences in specificity of liking soy sauce among the various user groups. This study provides insights into consumer liking and preference of semi-familiar foods, revealing the contribution of consumer traits and brand familiarity that may influence the spread of unfamiliar foods.

High-speed rotating device for X-ray tomography with 10 ms temporal resolution.

The temporal resolution of X-ray tomography, using a synchrotron radiation X-ray source, has been improved to millisecond order in recent years. However, the sample must be rotated at a speed of more than a few thousand revolutions per minute, which makes it difficult to control the environment around the sample. In this study, a high-speed rotation device has been developed, comprising two synchronized coaxial motors movable along the direction of the axis, which can stretch or compress the rotating sample. Using this device, tomograms of breaking rubber were successfully obtained at a temporal resolution of 10 ms.

Comparing Explicit and Implicit Measures for Assessing Cross-Cultural Food Experience.

The present study investigated the potential of implicit physiological measures to provide objective measures of affective food experience in contrast to explicit self-report ratings in a cross-cultural context. Dutch and Thai participants viewed 120 food images portraying universal food image categories (regular and molded food) and cultural food image categories (typically Dutch and Thai food). The universal food images were taken as ground truth high and low valence stimuli, where we assumed no genuine difference in affective experience between nationalities. In contrast, for the cultural food images, we did expect a genuine difference between nationalities. Participants were asked to rate valence, arousal and liking of each food image. In addition, heart rate (HR) and phasic electrodermal activity (EDA) responses to the images were recorded. Typically Asian and Western response biases were found for explicit ratings of regular and molded food with an extreme response style for Dutch, and a middle response style for Thai participants. However, such bias was not observed in HR. For cultural food image categories, HR showed the hypothesized interaction between participant nationality and food image category, reflecting the expected genuine difference between nationalities in affective food experience. Besides presenting participants with images, we also asked participants to taste typically Thai and Dutch drinks. Similar to images, a significant interaction between participant nationality and cultural food category was found for HR. An interaction was also found for sip size, while this was not seen in explicit measures. We attribute this to differences in the moment that these measures were taken. In this study, phasic EDA did not appear to be a sensitive measure of affective food experience, possibly since stimuli mostly differed in valence rather than arousal. To conclude, our study constitutes an example where cultural bias negatively affected the accuracy of self-reports, and only the implicit physiological measures followed the prior expectations of genuine food experience, indicating the potential of these measures to study cross-cultural food experience.

Effect of Branding and Familiarity of Soy Sauces on Valence and Arousal as Determined by Facial Expressions, Physiological Measures, Emojis, and Ratings.

Food experiences can be summarized along two main dimensions: valence and arousal, which can be measured explicitly with subjective ratings or implicitly with physiological and behavioral measures. Food experiences are not only driven by the food's intrinsic properties, such as its taste, texture, and aroma, but also by extrinsic properties such as brand information and the consumers' previous experiences with the foods. In this study, valence and arousal to intrinsic and extrinsic properties of soy sauce were measured in consumers that varied in their previous experience with soy sauce, using a combination of explicit (scores and emojis), implicit (heart rate and skin conductance), and behavioral measures (facial expressions). Forty participants, high- and low-frequency users, were presented with samples of rice and three commercial soy sauces without and with brand information that either matched or non-matched the taste of the soy sauce. In general, skin conductance and facial expressions showed relatively low arousal during exposure to the brand name and again lowest arousal during tasting. Heart rate was lowest during exposure to the brand name and increased during tasting probably resulting from the motor activity during chewing. Furthermore, the results showed that explicit liking and arousal scores were primarily affected by the taste of the specific soy sauce and by the participants' previous experience with soy sauces. These scores were not affected by branding information. In contrast, facial expressions, skin conductance, and heart rate were primarily affected by (1) the participants' level of experience with soy sauce, (2) whether or not branding information was provided, and (3) whether or not the branding information matched with the taste. In conclusion, this study suggests that liking scores may be most sensitive to the food's intrinsic taste properties, whereas implicit measures and facial expressions may be most sensitive to extrinsic properties such as brand information. All measures were affected by the consumers' previous food experiences.

Emotional State During Tasting Affects Emotional Experience Differently and Robustly for Novel and Familiar Foods.

Emotional state during food consumption is expected to affect food pleasantness. We hypothesize that a negative emotional state reduces food pleasantness and more so for novel foods than for familiar foods because novel foods have not yet been associated with previous emotions. Furthermore, we expect this effect to be stronger when judging the food again from memory without tasting. We induced a positive emotional state in 34 participants by telling them that they earned a monetary bonus and induced a negative emotional state in 35 other participants by subjecting them to a social stress test. After this emotion induction, both groups tasted and rated a (for them) novel soup (sumashi soup) and a familiar soup (vegetable soup). Several explicit and implicit measures of food pleasantness (rated valence, EsSense25, willingness-to-take-home and sip size) indicated that while the negative emotion group did not experience the soups as less pleasant than the positive emotion group, there was an interaction between food familiarity and emotional group. The positive emotion group experienced novel and familiar soups as equally pleasant, whereas the negative emotion group experienced the novel soup as relatively unpleasant and the familiar soup as pleasant. The latter result is consistent with a comforting effect of a familiar taste in a stressful situation. This effect remained in the ratings given 1 week later based on memory and even after retasting. Our results show that emotional state affects food pleasantness differently for novel and familiar foods and that such an effect can be robust.

Explicit and Implicit Responses to Tasting Drinks Associated with Different Tasting Experiences.

Probing food experience or liking through verbal ratings has its shortcomings. We compare explicit ratings to a range of (neuro)physiological and behavioral measures with respect to their performance in distinguishing drinks associated with different emotional experience. Seventy participants tasted and rated the valence and arousal of eight regular drinks and a "ground truth" high-arousal, low-valence vinegar solution. The discriminative power for distinguishing between the vinegar solution and the regular drinks was highest for sip size, followed by valence ratings, arousal ratings, heart rate, skin conductance level, facial expression of "disgust," pupil diameter, and Electroencephalogram (EEG) frontal alpha asymmetry. Within the regular drinks, a positive correlation was found between rated arousal and heart rate, and a negative correlation between rated arousal and Heart Rate Variability (HRV). Most physiological measures showed consistent temporal patterns over time following the announcement of the drink and taking a sip. This was consistent over all nine drinks, but the peaks were substantially higher for the vinegar solution than for the regular drinks, likely caused by emotion. Our results indicate that implicit variables have the potential to differentiate between drinks associated with different emotional experiences. In addition, this study gives us insight into the physiological temporal response patterns associated with taking a sip.

Additional Use of a 6-Fr Intra-Aortic Balloon Pump on Extracorporeal Membrane Oxygenation Was Effective in a Patient with Cardiogenic Shock with Low Pulse Pressure.

We report the case of a 79-year-old man with acute myocardial infarction caused by left main trunk lesion, who experienced cardiogenic shock during percutaneous coronary intervention (PCI). To reverse the cardiogenic shock, we initiated veno-arterial extra corporeal membrane oxygenation (VA-ECMO) without an intra-aortic balloon pump (IABP) due to the severe tortuosity of the left external iliac artery. Although PCI was successful, arterial pressure monitoring revealed that the pulse pressure was too low to recover from the cardiogenic shock of decreased cardiac contraction function (the left ventricular ejection fraction was 30%). Thus, we decided to use IABP from the brachial artery to improve the hemodynamics. Immediately after the deployment of a 6-Fr IABP system (Takumi) from the left brachial artery, the pulse pressure was restored and finally VA-ECMO was withdrawn from the patient without complications. Although using IABP in combination with VA-ECMO is a reasonable strategy for cardiogenic shock, the effectiveness of this combination remains controversial. In this case, IABP added to VA-ECMO clearly achieved an improvement of pulse pressure and vital signs. Based on this result, monitoring of the pulse waveform is an effective tool to determine whether the concomitant use of IABP with VA-ECMO is indicated. Moreover, when it is difficult to insert IABP from the femoral arteries, the use of a 6-Fr IABP system (Takumi) approaching from the brachial artery should be considered.

CROCUFID: A Cross-Cultural Food Image Database for Research on Food Elicited Affective Responses.

We present CROCUFID: a CROss-CUltural Food Image Database that currently contains 840 images, including 479 food images with detailed metadata and 165 images of non-food items. The database includes images of sweet, savory, natural, and processed food from Western and Asian cuisines. To create sufficient variability in valence and arousal we included images of food with different degrees of appetitiveness (fresh, unfamiliar, molded or rotten, spoiled, and partly consumed). We used a standardized photographing protocol, resulting in high resolution images depicting all food items on a standard background (a white plate), seen from a fixed viewing (45°) angle. CROCUFID is freely available under the CC-By Attribution 4.0 International license and hosted on the OSF repository. The advantages of the CROCUFID database over other databases are its (1) free availability, (2) full coverage of the valence - arousal space, (3) use of standardized recording methods, (4) inclusion of multiple cuisines and unfamiliar foods, (5) availability of normative and demographic data, (6) high image quality and (7) capability to support future (e.g., virtual and augmented reality) applications. Individuals from the United Kingdom (N = 266), North-America (N = 275), and Japan (N = 264) provided normative ratings of valence, arousal, perceived healthiness, and desire-to-eat using visual analog scales (VAS). In addition, for each image we computed 17 characteristics that are known to influence affective observer responses (e.g., texture, regularity, complexity, and colorfulness). Significant differences between groups and significant correlations between image characteristics and normative ratings were in accordance with previous research, indicating the validity of CROCUFID. We expect that CROCUFID will facilitate comparability across studies and advance experimental research on the determinants of food-elicited emotions. We plan to extend CROCUFID in the future with images of food from a wide range of different cuisines and with non-food images (for applications in for instance neuro-physiological studies). We invite researchers from all parts of the world to contribute to this effort by creating similar image sets that can be linked to this collection, so that CROCUFID will grow into a truly multicultural food database.

Takotsubo syndrome occurring concomitantly with pre-eclampsia: A case report.

Takotsubo syndrome (TTS) patients show transient ventricular dysfunction without coronary artery stenosis. We report a pregnant woman with TTS occurring concomitantly with severe pre-eclampsia (PE). A primiparous woman complained of dyspnea at 35 weeks of gestation. She showed severe PE, and cardiac ultrasound identified akinesis of the anterior lower wall. On the same day, emergent cesarean section was performed due to a nonreassuring fetus status, yielding a male infant with an umbilical artery pH of 6.851. Unfortunately, the neonate died of multiple organ failure. Following the delivery, her cardiac function markedly improved, and coronary angiography showed no coronary artery stenosis. Considering the clinical findings, we diagnosed the patient with TTS. Regarding antenatally occurring TTS, only six patients have been reported including the present one. Of the six patients, three had severe PE. Although previous reports on pregnancy-associated TTS described good maternal outcomes, antenatally occurring TTS complicated by severe PE may become critical for fetuses.

EmojiGrid: A 2D pictorial scale for cross-cultural emotion assessment of negatively and positively valenced food.

Because of the globalization of world food markets there is a growing need for valid and language independent self-assessment tools to measure food-related emotions. We recently introduced the EmojiGrid as a language-independent, graphical affective self-report tool. The EmojiGrid is a Cartesian grid that is labeled with facial icons (emoji) expressing different degrees of valence and arousal. Users can report their subjective ratings of valence and arousal by marking the location on the area of the grid that corresponds to the emoji that best represent their affective state when perceiving a given food or beverage. In a previous study we found that the EmojiGrid is robust, self-explaining and intuitive: valence and arousal ratings were independent of framing and verbal instructions. This suggests that the EmojiGrid may be a valuable tool for cross-cultural studies. To test this hypothesis, we performed an online experiment in which respondents from Germany (GE), Japan (JP), the Netherlands (NL) and the United Kingdom (UK) rated valence and arousal for 60 different food images (covering a large part of the affective space) using the EmojiGrid. The results show that the nomothetic relation between valence and arousal has the well-known U-shape for all groups. The European groups (GE, NL and UK) closely agree in their overall rating behavior. Compared to the European groups, the Japanese group systematically gave lower mean arousal ratings to low valenced images and lower mean valence ratings to high valenced images. These results agree with known cultural response characteristics. We conclude that the EmojiGrid is potentially a valid and language-independent affective self-report tool for cross-cultural research on food-related emotions. It reliably reproduces the familiar nomothetic U-shaped relation between valence and arousal across cultures, with shape variations reflecting established cultural characteristics.

EmojiGrid: A 2D Pictorial Scale for the Assessment of Food Elicited Emotions.

Research on food experience is typically challenged by the way questions are worded. We therefore developed the EmojiGrid: a graphical (language-independent) intuitive self-report tool to measure food-related valence and arousal. In a first experiment participants rated the valence and the arousing quality of 60 food images, using either the EmojiGrid or two independent visual analog scales (VAS). The valence ratings obtained with both tools strongly agree. However, the arousal ratings only agree for pleasant food items, but not for unpleasant ones. Furthermore, the results obtained with the EmojiGrid show the typical universal U-shaped relation between the mean valence and arousal that is commonly observed for a wide range of (visual, auditory, tactile, olfactory) affective stimuli, while the VAS tool yields a positive linear association between valence and arousal. We hypothesized that this disagreement reflects a lack of proper understanding of the arousal concept in the VAS condition. In a second experiment we attempted to clarify the arousal concept by asking participants to rate the valence and intensity of the taste associated with the perceived food items. After this adjustment the VAS and EmojiGrid yielded similar valence and arousal ratings (both showing the universal U-shaped relation between the valence and arousal). A comparison with the results from the first experiment showed that VAS arousal ratings strongly depended on the actual wording used, while EmojiGrid ratings were not affected by the framing of the associated question. This suggests that the EmojiGrid is largely self-explaining and intuitive. To test this hypothesis, we performed a third experiment in which participants rated food images using the EmojiGrid without an associated question, and we compared the results to those of the first two experiments. The EmojiGrid ratings obtained in all three experiments closely agree. We conclude that the EmojiGrid appears to be a valid and intuitive affective self-report tool that does not rely on written instructions and that can efficiently be used to measure food-related emotions.

Methods for Evaluating Emotions Evoked by Food Experiences: A Literature Review.

Besides sensory characteristics of food, food-evoked emotion is a crucial factor in predicting consumer's food preference and therefore in developing new products. Many measures have been developed to assess food-evoked emotions. The aim of this literature review is (i) to give an exhaustive overview of measures used in current research and (ii) to categorize these methods along measurement level (physiological, behavioral, and cognitive) and emotional processing level (unconscious sensory, perceptual/early cognitive, and conscious/decision making) level. This 3 × 3 categorization may help researchers to compile a set of complementary measures ("toolbox") for their studies. We included 101 peer-reviewed articles that evaluate consumer's emotions and were published between 1997 and 2016, providing us with 59 different measures. More than 60% of these measures are based on self-reported, subjective ratings and questionnaires (cognitive measurement level) and assess the conscious/decision-making level of emotional processing. This multitude of measures and their overrepresentation in a single category hinders the comparison of results across studies and building a complete multi-faceted picture of food-evoked emotions. We recommend (1) to use widely applied, validated measures only, (2) to refrain from using (highly correlated) measures from the same category but use measures from different categories instead, preferably covering all three emotional processing levels, and (3) to acquire and share simultaneously collected physiological, behavioral, and cognitive datasets to improve the predictive power of food choice and other models.

[Evaluation of Educational Effect of Problem-Posing System in Nursing Processing Study].

The nursing processing study is generally difficult, because it is important for nursing college students to understand knowledge and utilize it. We have developed an integrated system to understand, utilize, and share knowledge. We added a problem-posing function to this system, and expected that students would deeply understand the nursing processing study through the new system. This system consisted of four steps: create a problem, create an answer input section, create a hint, and verification. Nursing students created problems related to nursing processing by this system. When we gave a lecture on the nursing processing for second year students of A university, we tried to use the creating problem function of this system. We evaluated the effect by the number of problems and the contents of the created problem, that is, whether the contents consisted of a lecture stage or not. We also evaluated the correlation between those and regular examination and report scores. We derived the following: 1. weak correlation between the number of created problems and report score (r=0.27), 2. significant differences between regular examination and report scores of students who created problems corresponding to the learning stage, and those of students who created problems not corresponding to it (P<0.05). From these results, problem-posing is suggested to be effective to fix and utilize knowledge in the lecture of nursing processing theory.

Reduction of the off-flavor volatile generated by the yogurt starter culture including Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus in soymilk.

Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus establish a symbiotic relationship in milk; however, S. thermophilus predominantly grows in soymilk. This study determined that excess diacetyl was notably generated mainly by S. thermophilus in soymilk, and this flavor compound created an unpleasant odor in fermented soymilk. The addition of l-valine to soymilk reduced the amount of diacetyl and increased the levels of acetoin during fermentation by S. thermophilus . In addition, it was found that the expression of the ilvC gene was repressed and that of the als and aldB genes was stimulated in S. thermophilus by l-valine. Sensory evaluations with the triangle difference test and a preference test showed that the soymilk fermented with l-valine was significantly preferred compared with that without l-valine. In this study, we successfully controlled the metabolic flux of S. thermophilus in soymilk and produced more favorable fermented soymilk without the use of genetically modified lactic acid bacteria strains.

Double-stranded RNA of intestinal commensal but not pathogenic bacteria triggers production of protective interferon-ß.

The small intestine harbors a substantial number of commensal bacteria and is sporadically invaded by pathogens, but the response to these microorganisms is fundamentally different. We identified a discriminatory sensor by using Toll-like receptor 3 (TLR3). Double-stranded RNA (dsRNA) of one major commensal species, lactic acid bacteria (LAB), triggered interferon-ß (IFN-ß) production, which protected mice from experimental colitis. The LAB-induced IFN-ß response was diminished by dsRNA digestion and treatment with endosomal inhibitors. Pathogenic bacteria contained less dsRNA and induced much less IFN-ß than LAB, and dsRNA was not involved in pathogen-induced IFN-ß induction. These results identify TLR3 as a sensor to small intestinal commensal bacteria and suggest that dsRNA in commensal bacteria contributes to anti-inflammatory and protective immune responses.

Fermented soymilk increases voluntary wheel running activity and sexual behavior in male rats.

Wheel running by rodents is thought to reflect voluntary exercise in humans. The present study examined the effect of fermented soymilk (FSM) on voluntary wheel running in rats. FSM was prepared from soymilk (SM) using the bacteria Leuconostoc pseudomesenteroides. The rats were fed a normal diet for 3 weeks followed by a 3-week administration of diet containing FSM or SM (5% w/w), and then the diets were switched back to a normal diet for 3 weeks. The voluntary wheel running activity was increased by FSM administration, although no changes were observed by SM administration. This effect was observed 2 weeks after FSM administration and lasted 1 week after deprivation of FSM. Then we evaluated the effect of FSM on sexual behavior in male rats. FSM administration for 10 days significantly increased the number of mounts. The protein expression of tyrosine hydroxylase (TH) increased in the hippocampus by FSM administration and it is suggested that FSM may change norepinephrine or dopamine signaling in the brain. Our study provides the first evidence that FSM increases voluntary wheel running activity and sexual behavior and suggests that TH may be involved in these effects.