Supertaster, super reactive: oral sensitivity for bitter taste modulates emotional approach and avoidance behavior in the affective startle paradigm.

People differ in both their sensitivity for bitter taste and their tendency to respond to emotional stimuli with approach or avoidance. The present study investigated the relationship between these sensitivities in an affective picture paradigm with startle responding. Emotion-induced changes in arousal and attention (pupil modulation), priming of approach and avoidance behavior (startle reflex modulation), and subjective evaluations (ratings) were examined. Sensitivity for bitter taste was assessed with the 6-n-propylthiouracil (PROP)-sensitivity test, which discriminated individuals who were highly sensitive to PROP compared to NaCl (PROP-tasters) and those who were less sensitive or insensitive to the bitter taste of PROP. Neither pupil responses nor picture ratings differed between the two taster groups. The startle eye blink response, however, significantly differentiated PROP-tasters from PROP-insensitive subjects. Facilitated response priming to emotional stimuli emerged in PROP-tasters but not in PROP-insensitive subjects at shorter startle lead intervals (200-300ms between picture onset and startle stimulus onset). At longer lead intervals (3-4.5s between picture onset and startle stimulus onset) affective startle modulation did not differ between the two taster groups. This implies that in PROP-sensitive individuals action tendencies of approach or avoidance are primed immediately after emotional stimulus exposure. These results suggest a link between PROP taste perception and biologically relevant patterns of emotional responding. Direct perception-action links have been proposed to underlie motivational priming effects of the startle reflex, and the present results extend these to the sensory dimension of taste.

Olfactory and gustatory sensitivity in adults with attention-deficit/hyperactivity disorder.

Recently, research on olfactory functions in attention-deficit/hyperactivity disorder (ADHD) has become prominent, whereas gustation has never been investigated. Increased odor sensitivity was found in medication-naïve children with ADHD, but not in adult ADHD, which might be due to a dopaminergic dysregulation presumed to underlie this disorder. Taste sensitivity, in particular bitter sensitivity as a hereditary trait, also might be altered in ADHD. To examine olfactory and gustatory functions in adult ADHD patients, we assessed odor sensitivity by Sniffin' Sticks, taste sensitivity by taste strips, and bitter sensitivity by the one-solution test in women with ADHD (n = 12), Bulimia Nervosa (n = 12), and healthy control women (n = 12). Bulimia Nervosa as second patient group was included to control for effects of impulsivity. Preliminary results indicate that ADHD patients were significantly more often classified as tasters, i.e. perceived the bitter taste as more intense, compared to both bulimic patients and healthy controls. No group differences were found with regard to general odor and taste sensitivity. It is proposed that the higher frequency of tasters in ADHD patients might underlie a genetic variation of the bitter receptor-dependent signaling pathway associated with ADHD.

Gustofacial and olfactofacial responses in human adults.

Adults' facial reactions in response to tastes and odors were investigated in order to determine whether differential facial displays observed in newborns remain stable in adults who exhibit a greater voluntary facial control. Twenty-eight healthy nonsmokers (14 females) tasted solutions of PROP (bitter), NaCl (salty), citric acid (sour), sucrose (sweet), and glutamate (umami) differing in concentration (low, medium, and high) and smelled different odors (banana, cinnamon, clove, coffee, fish, and garlic). Their facial reactions were video recorded and analyzed using the Facial Action Coding System. Adults' facial reactions discriminated between stimuli with opponent valences. Unpleasant tastes and odors elicited negative displays (brow lower, upper lip raise, and lip corner depress). The pleasant sweet taste elicited positive displays (lip suck), whereas the pleasant odors did not. Unlike newborns, adults smiled with higher concentrations of some unpleasant tastes that can be regarded as serving communicative functions. Moreover, adults expressed negative displays with higher sweetness. Except for the "social" smile in response to unpleasant tastes, adults' facial reactions elicited by tastes and odors mostly correspond to those found in newborns. In conclusion, adults' facial reactions to tastes and odors appear to remain stable in their basic displays; however, some additional reactions might reflect socialization influences.

The Attitudes to Chocolate Questionnaire: psychometric properties and relationship to dimensions of eating.

The aim of the present study was to evaluate the psychometric properties of the Attitudes to Chocolate Questionnaire (ACQ). We analyzed the factor structure of the ACQ by conducting exploratory and confirmatory factor analyses in a sample of healthy adults and a sample of dietician students. Further, the relationship between the resulting ACQ factors and dimensions of eating behavior, personality, emotionality, and tests of the pleasantness, sweetness, and intensity of sugar and chocolate was examined. The results yielded a clear two-factor structure of the ACQ: The first factor (guilt) was composed of items concerning negative consequences of chocolate eating including the feeling of guilt. The second factor (craving) comprised items related to craving and emotional chocolate eating. Guilt correlated significantly with "emotional eating", "restrained eating", and with neuroticism. Craving correlated significantly with "emotional eating" and "external eating", with neuroticism, and with the "difficulty identifying feelings" facet of the Toronto Alexithymia Scale; further, it correlated highly with the average reported chocolate consumption and with the ratings of the intensity of taste of sugar. In conclusion, results support the validity of the German version of the ACQ and showed a stable factor structure and a good internal consistency.

How emotions affect eating: a five-way model.

Despite the importance of affective processes in eating behaviour, it remains difficult to predict how emotions affect eating. Emphasizing individual differences, previous research did not pay full attention to the twofold variability of emotion-induced changes of eating (variability across both individuals and emotions). By contrast, the present paper takes into account both individual characteristics and emotion features, and specifies five classes of emotion-induced changes of eating: (1) emotional control of food choice, (2) emotional suppression of food intake, (3) impairment of cognitive eating controls, (4) eating to regulate emotions, and (5) emotion-congruent modulation of eating. These classes are distinguished by antecedent conditions, eating responses and mediating mechanisms. They point to basic functional principles underlying the relations between emotions and biologically based motives: interference, concomitance and regulation. Thus, emotion-induced changes of eating can be a result of interference of eating by emotions, a by-product of emotions, and a consequence of regulatory processes (i.e., emotions may regulate eating, and eating may regulate emotions).

Interactive effects of emotional and restrained eating on responses to chocolate and affect.

To examine differences and interactions between emotional and restrained-eating healthy adults (56 women, 53 men) were classified into emotional or restrained eaters, and persons scoring high or low on both dimensions. Participants tasted different types of chocolate (with 30, 70, 85, or 99% cocoa content) and completed questionnaires on affect and attitudes towards chocolate. Emotional eaters reported increased craving for and increased consumption of chocolate, whereas restrained eaters experienced chocolate-related guilt. However, restrained eaters rated plain chocolate (70% and 85% cocoa) as more pleasant than other groups. Persons scoring high on both dimensions showed heightened negative affect and may be prone to disturbances of eating and affect.

Immediate effects of chocolate on experimentally induced mood states.

In this work two hypotheses were tested: (1) that eating a piece of chocolate immediately affects negative, but not positive or neutral mood, and (2) that this effect is due to palatability. Experiment 1 (48 normal-weight and healthy women and men) examined the effects of eating a piece of chocolate and drinking water on negative, positive and neutral mood states induced by film clips. Eating chocolate reduced negative mood compared to drinking water, whereas no or only marginal effects were found on neutral and positive moods. Experiment 2 (113 normal-weight and healthy women and men) compared effects of eating palatable and unpalatable chocolate on negative mood, and examined the duration of chocolate-induced mood change. Negative mood was improved after eating palatable chocolate as compared to unpalatable chocolate or nothing. This effect was short lived, i.e., it disappeared after 3 min. In both experiments, chocolate-induced mood improvement was associated with emotional eating. The present studies demonstrate that eating a small amount of sweet food improves an experimentally induced negative mood state immediately and selectively and that this effect of chocolate is due to palatability. It is hypothesized that immediate mood effects of palatable food contribute to the habit of eating to cope with stress.

Predictors of freezing in Parkinson's disease: a survey of 6,620 patients.

Data from a survey of 6,620 Parkinson's disease patients were examined for correlation of freezing with age, sex, duration, subjective severity of Parkinson's disease, and antiparkinsonian medication. Forty-seven percent of the patients reported experiencing freezing regularly. Logistic regression analysis showed that freezing was significantly associated with a longer disease duration and a more advanced stage of the disease. Freezing episodes were more likely in men than in women and in patients taking, in addition to levodopa, Entacapone, Amantadine, or dopamine agonists. Finally, patients considering tremor as their main symptom reported freezing less frequently. Common antiparkinsonian drugs given in combination with levodopa were not negatively correlated with freezing. The results underline the necessity to develop appropriate countermeasures against this phenomenon, which is widely known to cause significant impairment of patients' quality of life and - as our data also showed - may cause traffic accidents in licensed patients.

Patient education in Parkinson's disease: Formative evaluation of a standardized programme in seven European countries.

OBJECTIVE: To evaluate a newly developed education programme for Parkinson's disease (PD) patients. METHODS: The programme consisted of eight sessions and aimed at improving knowledge and skills related to self-monitoring, health promotion, stress management, depression, anxiety, social competence, and social support, all with special reference to PD. The programme was formatively evaluated in seven European countries (Spain, Finland, Italy, The Netherlands, United Kingdom, Estonia, Germany) with 151 patients diagnosed with idiopathic PD. The evaluation included patients' ratings of the comprehensibility and feasibility of the programme as well as mood ratings before and after each session. Patients also completed questionnaires at the beginning and end of the programme to explore possible changes in disease-related psychosocial problems, quality of life, and depression. RESULTS: The programme was feasible to run, and patients were able to understand its elements. Patients reported mood elevations following individual sessions and reduced disease-related psychosocial problems after completing the programme. There were no substantial differences in results between cultures. CONCLUSION: Patient education appears to have potential as a useful and feasible intervention, complementing medical treatment in PD. PRACTICE IMPLICATIONS: The present programme will soon be available in seven European languages and can be tested in different health care systems.

Increased negative emotional responses in PROP supertasters.

Based on animal data it has been suggested that an increased sensitivity to bitter tastes is linked with increased emotional reactivity. The present study examined for the first time in humans whether the intensity of experimentally induced negative emotional responses is related to sensitivity to the bitter tasting compound PROP (6-n-propylthiouracil). Normal-weight participants (61 men, 57 women) with a mean age of 24 years were classified into PROP non-tasters (n=54), medium tasters (n=25), or supertasters (n=39), and were shown two film clips to induce negative emotional response patterns: one pattern predominated by anger and tension, and another predominated by sadness and depressed mood. A third film clip was emotionally neutral. Before and after film clip viewing, self-rated emotional responses were obtained. PROP supertasters showed more intense responses than non-tasters or medium tasters after the anger-inducing film clip (increased anger, tension, sadness and fear as well as decreased mood and joy). Significant correlations were found between emotional responses and a continuos measure of PROP sensitivity. Group differences and correlations could not be attributed to personality measures, trait affectivity, or gender. For emotional responses after the sadness-inducing film clip, no differences between taster groups could be detected. PROP sensitivity appears to be related to arousability of emotions, in particular those emotions that are associated with an increased readiness to respond actively to stimuli from the environment, e.g. anger, disgust and fear.

Stress affects hedonic responses but not reaching-grasping in Parkinson's disease.

Stress can transiently increase motor symptoms of Parkinson's disease (PD), but it is unclear whether other behavioural changes associated with PD are also affected. We found that reaching-grasping was impaired in 19 PD patients compared with 19 matched controls, but these impairments were not amplified by stress. However, patients showed a stress-induced reduction of hedonic responses. Stress may amplify those impairments in PD that are not accessible to cognitive control.

Facial and affective reactions to tastes and their modulation by sadness and joy.

This study examined adults' affective and facial reactions to tastes which differ in quality and valence, and the impact of sadness and joy on these reactions. Thirty-six male and female subjects participated voluntarily. Subjects each tasted 6 ml of a sweet chocolate drink, a bitter quinine solution (0.0015 M) and a bitter-sweet soft drink. Following a baseline period, either joy or sadness was induced using film clips before the same taste stimuli were presented for a second time. Subjects rated the drinks' pleasantness and intensity of taste immediately after each stimulus presentation. Facial reactions were videotaped and analysed using the Facial Action Coding System (FACS [P. Ekman, W.V. Friesen, Facial Action Coding System: Manual. Palo Alto, CA: Consulting Psychologists Press; 1978., P. Ekman, W. Friesen, J. Hager, Facial Action Coding System. Salt Lake City, Utah: Research Nexus; 2002.]). The results strongly indicated that the tastes produced specific facial reactions that bear strong similarities to the facial reactivity patterns found in human newborns. The data also suggest that some adults' facial reactions serve additional communicative functions. Emotions modulated taste ratings, but not facial reactions to tastes. In particular, ratings of the sweet stimulus were modulated in congruence with emotion quality, such that joy increased and sadness decreased the pleasantness and sweetness of the sweet stimulus. No emotion-congruent modulation was found for the pleasantness and intensity ratings of the bitter or the bitter-sweet stimulus. This 'robustness' of bitter taste ratings may reflect a biologically meaningful mechanism.

Everyday mood and emotions after eating a chocolate bar or an apple.

Emotional changes after eating chocolate were examined in everyday life. Thirty-seven healthy, normal-weight women ate a chocolate bar, an apple or nothing and rated their subjective state 5, 30, 60 and 90min after eating. Both chocolate and the apple reduced hunger, elevated mood and increased activation, but the effects of the chocolate were stronger. Eating chocolate was also followed by joy and, in some women, by guilt. Guilt responders experienced less intense positive emotions. Whereas positive emotional responses appear to be due to sensory pleasure and it's anticipation and may also be related to reduced hunger, guilt responses are probably induced by negative food-related cognitions.

Emotion processing in Parkinson's disease: dissociation between early neuronal processing and explicit ratings.

OBJECTIVE: Patients suffering from Parkinson's disease (PD) have a diminished ability to discriminate facial expressions of emotion. We investigated early emotion discrimination deficits in PD by means of event-related potentials (ERPs). METHODS: Emotional pictures were presented to 14 PD patients and 14 healthy controls in a rapid serial visual presentation paradigm (three frames per second) while EEG was recorded. In addition, valence and arousal ratings were obtained for a representative subsample of 54 pictures. RESULTS: PD patients rated pictures of highly arousing content as less exciting than did healthy controls. Pictures of high compared to low emotional arousal were associated with a pronounced relative negative shift in the ERP waveform over parietal and occipital sites developing about 220 ms after picture onset. This early posterior negativity (EPN) did not differ between PD and control group. CONCLUSIONS: This dissociation of affective ratings and early ERP components supports the view that PD is associated with blunted emotional responses, but there is no evidence for a deteriorated early visual processing of emotional stimuli. SIGNIFICANCE: Frequently reported deficits in emotion discrimination are likely not due to deficits in early emotion processing.

The perceived function of eating is changed during examination stress: a field study.

Changes of eating in response to a real life stressor were examined in field study using a control group design with pre- and posttest. Students (n=22) awaiting an exam and control subjects (n=20) were assessed 3-4 weeks and 3-4 days before the exam. They were given a pager, which beeped ten times a day at random intervals. Upon each signal, participants rated their emotional state and motivations to eat. If they had eaten since the last signal they reported the perceived function of their actual eating behavior. Compared to control subjects, students awaiting an exam reported higher emotional stress and an increased tendency to eat in order to distract themselves from stress. Results indicate that emotion regulation through eating is experienced in a student population during stress under real life conditions with distraction as a possible mediating mechanism.

Emotions in overweight and normal-weight women immediately after eating foods differing in energy.

Immediate effects of low-, medium-, and high-energy foods on the emotional state of normal-weight and overweight women were studied experimentally. Nineteen normal-weight (body mass index [BMI]: 19-25 kg/m2) and 19 overweight women (BMI: 26-40 kg/m2) aged 18-40 years received samples of food that differed in energy content (low vs. medium vs. high energy) and rated their emotional state immediately after eating. Perceived characteristics of the foods and associations elicited by the foods were also obtained. Negative emotions (anger, fear, shame, and sadness) and sleepiness increased, while happiness decreased with energy of foods. Emotionally negative associations were more frequent, while positive emotions were less frequent the higher the energy content of the foods. Sadness, shame, fear, and sleepiness after eating high-energy food tended to be more intense in overweight women. Additional analyses demonstrated influences of eating habits, e.g., disinhibition. The higher the energy content of a food stimulus, the more it was viewed as "unhealthy" and "dangerous." It is suggested that immediate food-induced changes of emotions can be explained by activation of associative emotion networks.