Changes in neural processing and evaluation of negative facial expressions after administration of an open-label placebo.

A recent event-related potential (ERP) study found that an open-label placebo (OLP) reduced emotional distress during the viewing of unpleasant scenes and the amplitude of the late positive potential (LPP). The present ERP experiment aimed at a conceptual replication of this finding and investigated OLP effects during affective face processing. The participants (109 females) were presented with images depicting angry and neutral facial expressions after the administration of a saline nasal spray. The spray was either introduced as a placebo that could help reduce the emotional reactions to viewing angry faces (OLP group) or to improve the electrophysiological recordings (Control group). The OLP was associated with reduced LPP amplitudes (1000-6000 ms) to anger expressions across a frontal cluster. Additionally, the OLP reduced LPP amplitudes (400-1000 ms) to both anger and neutral faces across a centroparietal cluster. Compared to the Control group, the OLP group reported less arousal when confronted with angry faces, and rated the anger expressions as less intense. This study demonstrates that an OLP can alter both subjective and neural responses to anger cues. Future research should directly compare OLP treatment with other strategies for emotion regulation (e.g., cognitive reappraisal) to demonstrate the specificity of this approach.

The effects of imaginary eating on visual food cue reactivity: An event-related potential study.

Previous research has demonstrated that imagining consumption of a specific type of food helps individuals to consume less of that food. The present event-related potential study aimed at investigating the underlying neural correlates of this appetite-reducing strategy. A total of 86 women (mean age = 23.65 years) were randomly assigned to one of three imagination conditions. In each condition, they listened to a guided imagery script that either described the eating of 30 colorful button-shaped chocolates (M&Ms), the sorting of 30 M&Ms by color, or the sorting of 30 marbles by color. Subsequently to the imagery task, the participants were presented with images of M&Ms and marbles while their electroencephalogram and craving ratings were recorded. The results showed that imaginary eating did not reduce the appetitive value of M&M pictures. The M&M sorting group reported enhanced craving and showed increased late positivity toward M&M pictures (300-600 ms after picture onset) compared to the two other groups. The present findings indicate that the imagined handling of food increases food cue reactivity and that imaginary eating is not a reliable method to reduce appetite.

Self-Disgust and Its Relationship With Lifetime Suicidal Ideation and Behavior.

Background: The emotion disgust is typically directed toward stimuli in the external environment, but sometimes people develop self-directed disgust responses. Aims: The current questionnaire study focused on the role of self-disgust in lifetime suicidal ideation and behavior. Method: A total of 1,167 individuals participated in an Internet-based survey containing self-report measures of self-disgust, externally directed disgust proneness, coping styles, diagnoses of mental disorders, and suicide risk. Hierarchical regression analyses as well as mediation analyses were computed. Results: Self-disgust was the most relevant predictor of suicide risk among the assessed variables. Self-disgust was negatively associated with the use of support by others, and positively associated with evasive coping (self-blame, venting, denial), which in turn was positively associated with suicidality. Limitations: This cross-sectional study provided information on the relationship between self-disgust and suicidality in a self-selected sample. Longitudinal studies are warranted. Conclusion: Future studies are required to replicate these findings. Additionally, stronger research designs are needed in order to investigate whether self-disgust should be targeted in suicide prevention programs and interventions.

Placebos can change affective contexts: An event-related potential study.

An unpleasant context (bitter aftertaste) is able to reduce the late positive potential (LPP) elicited by affective pictures. This study attempted to influence this context with a placebo. Sixty-eight women were randomly assigned to three groups: Water, Bitter/No-Placebo, Bitter/Placebo. Participants in the 'bitter groups' first rinsed their mouth with wormwood tea that caused a bitter aftertaste. Subsequently, the placebo group received sham light therapy on the tongue to 'reduce the sensitivity of the taste buds'. All groups viewed disgusting and non-disgusting pictures while their electroencephalogram was recorded. The Bitter/Placebo group reported reduced bitterness and disgust for the aftertaste after the sham treatment. The LPP reduction (300-600 ms after picture onset) associated with the bitter aftertaste (as shown by the Bitter/No-Placebo group) was attenuated due to the placebo treatment. This is the first EEG study to demonstrate that a context-targeting placebo is able to change automatic attention allocation.

Disgust Proneness and Personal Space in Children.

Individuals vary in their personal space (PS) size as reflected by the preferred distance to another person during social interactions. A previous study with adults showed that pathogen-relevant disgust proneness (DP) predicted PS magnitude. The present study investigated whether this association between DP and PS already exists in 8- to 12-year-old children (144 girls, 101 boys). The children answered a disgust questionnaire with the two trait dimensions "core disgust (contact with spoiled food and poor hygiene) and "death-relevant disgust" (imagined contact with dead and dying organisms). PS magnitude was assessed with a paper-pencil measure (drawing a PS bubble; Experiment 1) or with the stop-distance task (preferred distance to an approaching woman or man; Experiment 2). In both experiments, only death-related disgust predicted PS magnitude and only if the approaching person was male. The current study questions the relevance of pathogen-related disgust in children for regulating interpersonal distance.

Aversive aftertaste changes visual food cue reactivity: An fMRI study on cross-modal perception.

In western cultures, we are surrounded by appealing visual food cues that stimulate our desire to eat, overeating and subsequent weight gain. Cognitive control of appetite (reappraisal) requires substantial attentional resources and effort in order to work. Therefore, we tested an alternative approach for appetite regulation via functional magnetic resonance imaging. Healthy, normal-weight women were presented with images depicting food (high-/low-caloric), once in combination with a bitter aftertaste (a gustatory stop signal) and once with a neutral taste (water), in a retest design. The aversive aftertaste elicited increased activation in the orbitofrontal/dorsolateral prefrontal cortex (OFC, DLPFC), striatum and frontal operculum during the viewing of high-caloric food (vs. low-caloric food). In addition, the increase in DLPFC activity to high-caloric food in the bitter condition was correlated with reported appetite reduction. The findings indicate that this aftertaste procedure was able to reduce the appetitive value of visual food cues.

Placebo effects in spider phobia: an eye-tracking experiment.

Several eye-tracking studies have revealed that spider phobic patients show a typical hypervigilance-avoidance pattern when confronted with images of spiders. The present experiment investigated if this pattern can be changed via placebo treatment. We conducted an eye-tracking experiment with 37 women with spider phobia. They looked at picture pairs (a spider paired with a neutral picture) for 7 s each in a retest design: once with and once without a placebo pill presented along with the verbal suggestion that it can reduce phobic symptoms. The placebo was labelled as Propranolol, a beta-blocker that has been successfully used to treat spider phobia. In the placebo condition, both the fixation count and the dwell time on the spider pictures increased, especially in the second half of the presentation time. This was associated with a slight decrease in self-reported symptom severity. In summary, we were able to show that a placebo was able to positively influence visual avoidance in spider phobia. This effect might help to overcome apprehension about engaging in exposure therapy, which is present in many phobic patients.

Is this blood? An ERP study on the visual identification of red fluids in patients with blood phobia.

Blood can be easily recognized in situations involving injury. However, very little is known about the ability of humans to identify blood without such context information. We investigated the blood detection capacity and associated electrocortical correlates (event-related potentials) in 20 women with blood phobia and 20 non-phobic females. The participants viewed images depicting droplets of pig blood, and water with pink or red food coloring. They were asked to decide, whether the pictures showed real blood or not. Blood provoked enhanced P100 amplitudes (90-140 ms) in blood phobics. Late positivity (P300: 340-500 ms) as well as classification accuracy did not differ between the groups. However, blood elicited a general P300 enhancement (relative to red and pink fluids) possibly reflecting elevated visual attention to blood as a general characteristic in humans. The P100 augmentation in blood phobics very likely reflects enhanced early selective attention. Patients with BII phobia showed prioritized visual processing of blood without having to rely on contextual information.

Facial affect processing in social anxiety disorder with early onset: evidence of an intensity amplification bias.

The present event-related potential (ERP) study investigated for the first time whether children with early-onset social anxiety disorder (SAD) process affective facial expressions of varying intensities differently than non-anxious controls. Participants were 15 SAD patients and 15 non-anxious controls (mean age of 9 years). They were presented with schematic faces displaying anger and happiness at four intensity levels (25%, 50%, 75%, and 100%), as well as with neutral faces. ERPs in early and later time windows (P100, N170, late positivity [LP]), as well as affective ratings (valence and arousal) for the faces, were recorded. SAD patients rated the faces as generally more arousing, regardless of the type of emotion and intensity. Moreover, they displayed enhanced right-parietal LP (350-650 ms). Both arousal ratings and LP reflect stimulus intensity. Therefore, this study provides first evidence of an intensity amplification bias in pediatric SAD during facial affect processing.

Processing of visual food cues during bitter taste perception in female patients with binge-eating symptoms: A cross-modal ERP study.

OBJECTIVE: In healthy individuals, the perception of an intense bitter taste decreased the reward value of visual food cues, as reflected by the reduction of a specific event-related brain potential (ERP), frontal late positivity. The current cross-modal ERP study investigated responses of female patients with binge-eating symptoms (BES) to this type of visual-gustatory stimulation. METHODS: Women with BES (n=36) and female control participants (n=38) viewed food images after they rinsed their mouth with either bitter wormwood tea or water. RESULTS: Relative to controls, the patients showed elevated late positivity (LPP: 400-700ms) to the food images in the bitter condition. The LPP source was located in the medial prefrontal cortex. Both groups did not differ in the ratings for the fluids (intensity, bitterness, disgust). CONCLUSIONS: This ERP study showed that a bitter taste did not decrease late positivity to visual food cues (reflecting food reward) in women with BES. SIGNIFICANCE: The atypical bitter responding might be a biological marker of this condition and possibly contributes to overeating. Future studies should additionally record food intake behavior to further investigate this mechanism.

Facial emotion processing in pediatric social anxiety disorder: Relevance of situational context.

Social anxiety disorder (SAD) typically begins in childhood. Previous research has demonstrated that adult patients respond with elevated late positivity (LP) to negative facial expressions. In the present study on pediatric SAD, we investigated responses to negative facial expressions and the role of social context information. Fifteen children with SAD and 15 non-anxious controls were first presented with images of negative facial expressions with masked backgrounds. Following this, the complete images which included context information, were shown. The negative expressions were either a result of an emotion-relevant (e.g., social exclusion) or emotion-irrelevant elicitor (e.g., weight lifting). Relative to controls, the clinical group showed elevated parietal LP during face processing with and without context information. Both groups differed in their frontal LP depending on the type of context. In SAD patients, frontal LP was lower in emotion-relevant than emotion-irrelevant contexts. We conclude that SAD patients direct more automatic attention towards negative facial expressions (parietal effect) and are less capable in integrating affective context information (frontal effect).

Influence of Bitter Taste on Affective Facial Processing: An ERP Study.

Previous research showed that a bitter taste in the mouth is able to enhance hostile response tendencies to social rejection. The present event-related potential (ERP) study sought to investigate neuronal components of this effect. We presented 52 participants (39 women and 13 men; mean age = 23.3 years) with images of facial expressions signaling social rejection (angry, disgusted) or no rejection (happy, neural), whereas they either experienced a bitter aftertaste (bitter group [BG]: n = 26) or rinsed their mouth with water (control group [CG]: n = 26). The BG rated the aftertaste as extremely intense and disgusting and showed a decreased parietal P200 to all facial expressions, as well as a lowered parietal P300 to cues of nonrejection. The bitter intervention neither influenced the affective ratings for the images nor self-reported hostility. In conclusion, the ERP findings indicated that bitterness first reduced visual attention to social cues in general (P200) and then specifically to cues of nonrejection (P300). Bitterness was not associated with increased sensitivity to disgust/anger signaled by others neither on a neuronal nor self-report level.

Disgust evoked by strong wormwood bitterness influences the processing of visual food cues in women: An ERP study.

The perception of intense bitterness is associated with disgust and food rejection. The present cross-modal event-related potential (ERP) study investigated whether a bitter aftertaste is able to influence affective ratings and the neuronal processing of visual food cues. We presented 39 healthy normal-weight women (mean age: 22.5 years) with images depicting high-caloric meat dishes, high-caloric sweets, and low-caloric vegetables after they had either rinsed their mouth with wormwood tea (bitter group; n = 20) or water (control group; n = 19) for 30s. The bitter aftertaste of wormwood enhanced fronto-central early potentials (N100, N200) and reduced P300 amplitudes for all food types (meat, sweets, vegetables). Moreover, meat and sweets elicited higher fronto-central LPPs than vegetables in the water group. This differentiation was absent in the bitter group, which gave lower arousal ratings for the high-caloric food. We found that a minor intervention ('bitter rinse') was sufficient to induce changes in the neuronal processing of food images reflecting increased early attention (N100, N200) as well as reduced affective value (P300, LPP). Future studies should investigate whether this intervention is able to influence eating behavior.

The time-course of EEG alpha power changes in creative ideation.

Increases in EEG alpha power during creative ideation are among the most consistent findings in the neuroscientific study of creativity, but existing studies did not focus on time-related changes of EEG alpha activity patterns during the process of creative ideation so far. Since several cognitive processes are involved in the generation of creative ideas, different EEG correlates may result as a function of time. In this study we addressed this crucial point. Forty-five participants worked on the "Alternative Uses Task" while the EEG was recorded and changes in task-related power (relative to rest) in the upper-frequency band (10-12 Hz) for three isochronous time intervals of the idea generation period were determined. Alpha power changes during idea generation followed a characteristic time course: we found a general increase of alpha power at the beginning of idea generation that was followed by a decrease and finally by a re-increase of alpha prior to responding that was most pronounced at parietal and temporal sites of the right hemisphere. Additionally, the production of more original ideas was accompanied by increasing hemispheric asymmetry (more alpha in the right than left hemisphere) with increasing duration of the idea generation period. The observed time course of brain activity may reflect the progression of different but well-known stages in the idea generation process: that is the initial retrieval of common and old ideas followed by the actual generation of novel and more creative ideas by overcoming typical responses through processes of mental simulation and imagination.

First and second language in the brain: neuronal correlates of language processing and spelling strategies.

This study explores oscillatory brain activity by means of event-related synchronization and desynchronization (%ERS/ERD) of EEG activity during the use of phonological and orthographic-morphological spelling strategies in L2 (English) and L1 (German) in native German speaking children. EEG was recorded while 33 children worked on a task requiring either phonological or orthographic-morphological spelling strategies. L2 processing elicited more theta %ERS than L1 processing (particularly at bilateral frontal and right posterior parietal sites) which might suggest a stronger involvement of semantic encoding and retrieval of the less familiar L2. The highest level of theta %ERS was revealed for the orthographic-morphological strategy in L2 which might indicate a more intense way of lexical retrieval compared to the phonological strategy in L2 and the orthographic-morphological strategy in L1. Analyses moreover revealed that phonological processing (both in L1 and L2) was associated with comparatively strong left-hemispheric %ERD in the upper alpha frequency band.

Sensitivity of EEG upper alpha activity to cognitive and affective creativity interventions.

We investigated whether creative cognition can be improved by means of cognitive and affective stimulation and whether these interventions are associated with changes of EEG alpha activity. Participants were required to generate original uses of conventional objects (Alternative Uses task, AU) while the EEG was recorded. In the cognitive stimulation condition, participants worked on the AU task subsequent to the exposure to other people's ideas. In the affective stimulation condition, they had to think creatively in positive affective states, induced via emotionally contagious sound clips. Creative cognition generally elicited alpha synchronization, most prominent in the prefrontal cortex and in the right hemisphere. The interventions were associated with stronger prefrontal alpha activity in the upper alpha band (10-12 Hz) than the control condition (no intervention), possibly indicating a state of heightened internal awareness, which might have a beneficial impact on creativity.