Decomposing unpleasantness: Differential exogenous attention to disgusting and fearful stimuli

Neural mechanisms underlying attentional bias modification in fibromyalgia patients: a double-blind ERP study

There is a growing interest in the potential benefits of attentional bias modification (ABM) training in chronic pain patients. However, studies examining the effectiveness of ABM programs in fibromyalgia patients have demonstrated inconclusive effects on both behavioral indices and clinical symptoms. Additionally, underlying neural dynamics of ABM effects could yield new insights but remain yet unexplored. Current study, therefore, aims to investigate the effects of ABM training on known neural electrophysiological indicators of attentional bias to pain (P2, N2a). Thirty-two fibromyalgia patients were enrolled and randomly assigned to an ABM training (N = 16) or control (N = 16) condition (2 weeks duration). Within the ABM training condition participants performed five sessions consisting of a modified version of the dot-probe task in which patients were trained to avoid facial pain expressions, whereas in the control group participants performed five sessions consisting of a standard version of the dot-probe task. Potential ABM training effects were evaluated by comparing a single pre- and post-treatment session, in which event-related potentials (ERPs) were recorded in response to both facial expressions and target stimuli. Furthermore, patients filled out a series of self-report questionnaires assessing anxiety, depression, pain-related worrying, fear of pain, fatigue and pain status. After training, results indicated an overall reduction of the amplitude of the P2 component followed by an enhancement of N2a amplitude for the ABM condition compared to control condition. In addition, scores on anxiety and depression decreased in patients assigned to the training condition. However, we found no effects derived from the training on pain-related and fatigue status. Present study offers new insights related to the possible neural mechanisms underlying the effect of ABM training in fibromyalgia. Clinical trial (TRN: NCT05905159) retrospectively registered (30/05/2023).

The effects of yohimbine and hydrocortisone on selective attention to fearful faces: An fMRI study

INTRODUCTION

Selective attention to salient emotional information can enable an advantage in the face of danger. The present study aims to investigate the influence of the stress neuromodulators, norepinephrine and cortisol, on selective attention processes to fearful faces and its neuronal activation.

METHODS AND MATERIALS

We used a randomized, double-blind, placebo-controlled design. 167 healthy men between 18 and 35 years (mean [SD] age: 25.23 [4.24] years) participated in the study. Participants received either: (A) yohimbine (n= 41), (B) hydrocortisone (n = 41), (C) yohimbine and hydrocortisone (n = 42) or (D) placebo only (n= 43) and participated in a dot-probe task with fearful and neutral faces in an fMRI scanner.

RESULTS

We found an attentional bias toward fearful faces across all groups and related neuronal activation in the left cuneus. We did not find any differences between experimental treatment groups in selective attention and its neuronal activation.

DISCUSSION

Our results provide evidence that fearful faces lead to an attentional bias with related neuronal activation in the left cuneus. We did not replicate formerly reported activation in the amygdala, intraparietal sulcus, dorsal anterior cingulate cortex, and thalamus. Suitability of the dot-probe task for fMRI studies and insignificant treatment effects are discussed.

Electrophysiological Correlates of Amplified Emotion-Related Cognitive Processing Evoked by Self-Administered Disgust Images

In the processing of emotions, the brain prepares and reacts in distinctive manners depending upon the negative or positive nuance of the emotion elicitors. Previous investigations showed that negative elicitors generally evoke more intense neural activities than positive and neutral ones, as reflected in the augmented amplitude of all sub-components of the event-related potentials (ERP) late posterior positivity (LPP) complex, while less is known about the emotion of disgust. The present study aimed to examine whether the LPP complex during the processing of disgust stimuli showed greater amplitude than other emotion elicitors with negative or positive valences, thus confirming it as a neural marker of disgust-related negativity bias at earlier or later stages. Thus, in the present study, we leveraged the ERP technique during the execution of an affective self-administered visual stimuli task to disentangle the neural contributions associated with images of positive, negative, disgust, or neutral emotions. Crucially, we showed that handling with disgust elicitors prompted the greatest neural activity and the highest delay during self-administration. Overall, we demonstrated progressive neural activities associated with the unpleasantness of the emotion elicitors and peculiar processing for disgust compared with all other emotions.

Disgust as a basic, sexual, and moral emotion

Disgust is a basic emotion that increases the organism's survival success by preventing the transfer of pathogens. In this regard, it directs cognitive processes and motivates avoidance behaviors that prevent pathogens from entering the body. Moreover, disgust has many specific characteristics that distinguish it from other basic emotions. Firstly, unlike other basic emotions, it contaminates neutral objects around it and causes difficult-to-change learning. Another specific characteristic of disgust is that it depends on ideational processes. Objects, situations, and behaviors that do not contain pathogens can also cause disgust. In this regard, disgust appears not only as a basic emotion but also as different adaptations in different fields. In this context, two distinct adaptations of disgust stand out: sexual and moral disgust. These two adaptations of disgust benefit from disgust-related behaviors and motivations in different ways. Sexual disgust works as a gene protection mechanism, while moral disgust helps maintain social rules. The specific characteristics of disgust and its effects on cognitive processes such as attention and memory interact. In conclusion, the multifaceted structure of disgust shows that it needs to be studied more in the subfields of psychology. (Strohminger, Philos Compass 9:478-493, 2014) defines disgust as a psychological nebula that needs to be discovered. However, it is observed that disgust has not been adequately addressed. This review aims to comprehensively explore unique characteristics and diverse aspects of disgust, shedding light on its significance from various perspectives. This study underscores the broader understanding of disgust and its pivotal role in psychological research.

A comparative study of the attentional blink of facial expression in deaf and hearing children

The rapid serial visual presentation paradigm was used to investigate differences in the attentional blink between deaf children and hearing children in response to facial expressions of fear and disgust. The results showed that: (1) deaf and hearing children had a higher accuracy rate for T1 with disgustful facial expression than T1 with fear facial expression, (2) There was no significant difference in attentional blink between deaf and hearing children, (3) When T2 appeared at Lag6, the response accuracy of T2 in the disgust T1 condition was lower than that in fear T1 condition. However, no significant difference in T2 at Lag2 was found between the two conditions. The results showed that deaf children and those with hearing were more sensitive to facial expressions of disgust, which captured more attentional resources, and the ability of visual attention of deaf children was not weaker than hearing children.

Ewww-Investigating the neural basis of disgust in response to naturalistic and pictorial nauseating stimuli

Emotion induction in psychological and neuroscientific research has been mostly done by presenting participants with picture or film material. However, it is debatable whether this passive approach to emotion induction results in an affective state comparable to real-life emotions, and if the neural correlates of emotion processing are ecologically valid. To investigate the appropriateness of pictures for the induction of emotions, we presented 56 participants in a within-subjects design with naturalistic disgusting and neutral stimuli as well as with pictures of said stimulus material while recording continuous EEG data. We calculated asymmetry indices (AIs) for alpha power as an index of emotion processing and emotion regulation at the F3/4, F5/6, F7/8, and O1/2 electrode pairs. Participants reported higher disgust ratings for disgusting naturalistic compared to disgusting pictorial stimuli. Investigating changes in the EEG signal in participants with a pronounced disgust response (n = 38), we found smaller AIs for naturalistic stimuli compared to pictures. Moreover, in this disgusted sub-sample, there were smaller AIs in response to naturalistic disgusting stimuli compared to pictorial disgusting and neutral stimuli at the O1/2 electrode pair indicating stronger activation of the right relative to the left hemisphere by naturalistic stimuli. As the right hemisphere has been shown to display dominance in processing negative and withdrawal-associated emotions, this might indicate that naturalistic stimuli are more appropriate for the induction of emotions than picture stimuli. To improve the validity of results from emotion induction, future research should incorporate stimulus material that is as naturalistic as possible.

Spatial Attention to Emotional Images and Psychopathic Personality Traits

Psychopathy has often been thought to be associated with a deficit in processing of the affective content of stimuli. This hypothesis was tested by examining if stimuli that depicted a threat to the viewer, or stimuli that depicted distressing scenes, would produce an automatic shift in spatial attention, and whether this effect would be modified by individual differences in trait psychopathy as conceptualised by the triarchic model of psychopathy. Using a large mixed gender community sample (N = 286) it was found that spatial attention was averted away from threat stimuli for both short (200 ms) and long (500 ms) periods from cue to target, while the distress cues did not produce any spatial attention shifts. The trait of Meanness was found to be associated with a reduction in the effect of threat stimuli, while the trait of Disinhibition was found to be associated with an increase in this threat effect. However, the dot-probe task showed poor reliability. We conclude that the callous unemotional aspects of psychopathy, as captured by the Meanness scale, are underpinned by a lack of response to affective information, whereas impulsive/irresponsible traits of psychopathy, as captured by the Disinhibition scale, are underpinned by an exaggerated response to such affective information.

Impact of depressed state on attention and language processing during news broadcasts: EEG analysis and machine learning approach

While information enriches daily life, it can also sometimes have a negative impact, depending on an individual's mental state. We recorded electroencephalogram (EEG) signals from depressed and non-depressed individuals classified based on the Beck Depression Inventory-II score while they listened to news to clarify differences in their attention to affective information and the impact of attentional bias on language processing. Results showed that depressed individuals are characterized by delayed attention to positive news and require a more increased load on language processing. The feasibility of detecting a depressed state using these EEG characteristics was evaluated by classifying individuals as depressed and non-depressed individuals. The area under the curve in the models trained by the EEG features used was 0.73. This result shows that individuals' mental states may be assessed based on EEG measured during daily activities like listening to news.

Common and separable behavioral and neural mechanisms underlie the generalization of fear and disgust

Generalization represents the transfer of a conditioned responses to stimuli that resemble the conditioned stimulus (CS). Previous studies on generalization of defensive avoidance responses have primarily focused on fear and have neglected disgust generalization, which represents a key pathological mechanism in some anxiety disorders. In the present study we examined common and distinct mechanisms of fear and disgust generalization by means of a fear or disgust multi-CS conditioning and generalization paradigm with concomitant event-related potential (ERPs) acquisition in n = 62 subjects. We demonstrate that compared to fear, disgust-relevant generalized stimuli (GS) elicited larger expectancy ratings and longer reaction times (RTs) reflecting stronger ratings of 'risk'. On the electrophysiological level, increased P2 amplitudes were found in response to conditioned CS+ versus CS- across both domains, possibly reflecting higher motivational and attentional salience of aversive conditioned stimuli per se. Contingent negative variation (CNV) amplitude was significantly larger for disgust-CS+ than disgust-CS-, reflecting a stronger preparation of the disgust US. Additionally, we found that the contingent negative variation (CNV) fear generalization gradient, and CNV amplitude were increased with similarity to CS+. In contrast the CNV to disgust-GS did not differ and did not reflect disgust generalization. Together this may indicate that the CNV represents a highly fear-specific index for generalization learning. This study provides the first neurobiological evidence for common and distinct generalization learning in fear versus disgust suggesting that dysregulations in separable defensive avoidance mechanisms may underly different anxiety disorder subtypes.

Perception of semantic relations in scenes: A registered report study of attention hold

To what extent the semantic relations present in scenes guide spatial attention automatically remains a matter of debate. Considering that spatial attention can be understood as a sequence of shifts, engagements, and disengagements, semantic relations might affect each stage of this process differently. Therefore, we investigated whether objects that violate semantic rules engage attention for longer than objects that are expected in a given context. The experiment involved a central presentation of a distractor scene that contained a semantically congruent or incongruent object, and a peripheral presentation of a small target letter. We found that incongruent scenes did not delay responses to the peripheral target, which indicates that they did not hold attention for longer than congruent scenes. Therefore, by showing that violations of semantic relations do not engage attention automatically, our study contributes to a better understanding of how attention operates in naturalistic settings.

A reduction in the pupil's response to affective sounds in psychopathy and related personality traits

The pupil of the eye dilates in response to affective information, even if that information is not visual. We used this affective modulation of the pupil to examine the hypothesis that individuals with high traits of psychopathy have an insensitivity to emotional stimuli. We also examined general personality traits related to psychopathy. A sample of 120 healthy young men had their pupils monitored while they listened to sound clips that conveyed either neutral emotion (e.g., rain), negative emotion (e.g., a person screaming) or positive emotion (e.g., people laughing). Psychopathy and general personality traits were measured via self-report questionnaire. As expected, both the positive and negative emotional sounds produced greater dilation in the pupil size than neutral sounds. This affective modulation of the pupil was found to be reduced for the negative sounds for people high on the "callous/affective" components of psychopathy (the Affective facet of the SRP-4 and the Meanness scale of the TriPM) and the general personality traits of Reward Dependence and Cooperativeness. The results indicate that these callous traits of psychopathy and general personality may be underpinned by a reduction in the ability to effectively process or monitor emotional stimuli.

Exploration of Exogenous Attention to Disgust and Fear Pictures with Different Spatial Frequencies Through Event-related Potentials

The study of the effects of fear and disgust on the capture of automatic attention is gaining interest. Most findings reveal a more efficient capture of exogenous attention by disgust than by fear stimuli, although the underlying mechanisms are not completely understood. The manipulation of their spatial frequency may provide new insight that may contribute to clarify this issue. The present study aimed to explore differential processing of disgust and fear scenes containing only low spatial frequencies (LSF) or all spatial frequencies (intact) presented as distractors in an exogenous attention task. Event-related potentials (ERPs) and behavioral responses were recorded as dependent variables from forty participants (29 women). The results showed that disgust and fear distractors captured exogenous attention equally early, as indicated by the augmented amplitude of the N2p, and later disgust distractors are the ones eliciting the highest amplitude of the LPP component. While in an initial stage, both stimuli seem to have similar preferential access to further processing allowing fast responding in both cases, disgust is more deeply processed at a later stage probably facilitating its examination. These findings suggest that exploring the temporal course of processing is relevant for the understanding of the differential capture of exogenous attention by disgust and fear distractors.

Dimensionally Specific Attention Capture in Birds Performing Auditory Streaming Task

Previous studies in budgerigars (Melopsittacus undulatus) have indicated that they experience attention capture in a qualitatively similar way to humans. Here, we apply a similar objective auditory streaming paradigm, using modified budgerigar vocalizations instead of ABAB-… patterned pure tones, in the sound sequences. The birds were trained to respond to deviants in the target stream while ignoring the distractors in the background stream. The background distractor could vary among five different categories and two different sequential positions, while the target deviants could randomly appear at five different sequential positions and vary among two different categories. We found that unpredictable background distractors could deteriorate birds' sensitivity to the target deviants. Compared to conditions where the background distractor appeared right before the target deviant, the attention capture effect decayed in conditions when the background distractor appeared earlier. In contrast to results from the same paradigm using pure tones, the results here are evidence for a faster recovery from attention capture using modified vocalization segments. We found that the temporally modulated background distractor captured birds' attention more and deteriorated birds' performance more than other categories of background distractor, as the temporally modulated target deviant enabled the birds to focus their attention toward the temporal modulation dimension. However, different from humans, birds have lower tolerances for suppressing the distractors from the same feature dimensions as the targets, which is evidenced by higher false alarm rates for the temporally modulated distractor than other distractors from different feature dimensions.

Neural correlates of the attentional bias towards pain-related faces in fibromyalgia patients: An ERP study using a dot-probe task

BACKGROUND

One of the major cognitive deficits in fibromyalgia has been linked to the hypervigilance phenomenon. It is mainly reflected as a negative bias for allocating attentional resources towards both threatening and pain-related information. Although the interest in its study has recently grown, the neural temporal dynamics of the attentional bias in fibromyalgia still remains an open question.

METHOD

Fifty participants (25 fibromyalgia patients and 25 healthy control subjects) performed a dot-probe task. Two types of facial expressions (pain-related and neutral) were employed as signal stimuli. Then, as a target stimulus, a single dot replaced the location of one of these two faces. Event-related potentials (ERP) in response to facial expressions and target stimulation (i.e., dot) were recorded. Reaction time (RT) and accuracy measures in the experimental task were collected as behavioural outcomes.

RESULTS

Temporal dynamics of brain electrical activity were analysed on two ERP components (P2 and N2a) sensitive to the facial expressions meaning. Pain-related faces elicited higher frontal P2 amplitudes than neutral faces for the whole sample. Interestingly, an interaction effect between group and facial expressions was also found showing that pain-related faces elicited enhanced P2 amplitudes (at fronto-central regions, in this case) compared to neutral faces only when the group of patients was considered. Furthermore, higher P2 amplitudes were observed in response to pain-related faces in patients with fibromyalgia compared to healthy control participants. Additionally, a shorter latency of P2 (at centro-parietal regions) was also detected for pain-related facial expressions compared to neutral faces. Regarding the amplitude of N2a, it was lower for patients as compared to the control group. Non-relevant effects of the target stimulation on the ERPs were found. However, patients with fibromyalgia exhibited slower RT to locate the single dot for incongruent trials as compared to congruent and neutral trials.

CONCLUSIONS

Data suggest the presence of an attentional bias in fibromyalgia that it would be followed by a deficit in the allocation of attentional resources to further process pain-related information. Altogether the current results suggest that attentional biases in fibromyalgia might be explained by automatic attentional mechanisms, which seem to be accompanied by an alteration of more strategic or controlled attentional components.

Disgusting Face, Disease-Ridden Place?: Emoji Influence on the Interpretation of Restaurant Inspection Reports

Every year, millions of Americans get sick from foodborne illness and it is estimated half of all reported instances occur at restaurants. To protect the public, regulators are encouraged to conduct restaurant inspections and disclose reports to consumers. However, inspection reporting format is inconsistent and typically contains information unclear to most consumers who often misinterpret the inspection results. Additionally, consumers are increasingly searching for this information in a digital context. Limited research explores inspection reports as communication tools. Using affect-as-information and ELM as theoretical frameworks, this experiment investigated how discrete emotions (e.g., disgust) conveyed through pictorial cues (i.e., emojis) influenced consumers' processing of inspection reports. Participants, recruited from Amazon's MTurk, were randomly assigned to one of six experimental conditions in a 3 (emoji: smiling vs. disgusted vs. none) x 2 (violation level: low vs. high) between-subjects design. Then, participants completed a questionnaire regarding perceptions and cognitive processing of the message. Results revealed that, compared to text, disgusted face emoji increased risk perceptions and avoidance behavior. In terms of emotion, smiling face emoji motivated participants to feel more emotions related to sanitation. In turn, positive feelings decreased elaboration likelihood. As predicted by ELM, involvement also predicted elaboration, such that participants who were highly involved with inspection reports elaborated more than those less involved. Involvement also moderated the relationship between emoji presented and elaboration. Practical implications are also discussed.

Mechanisms underlying memory enhancement for disgust over fear

Disgust is remembered better than fear, despite both emotions being highly negative and arousing. But the mechanisms underlying this effect are not well-understood. Therefore, we compared two proposed mechanisms underlying superior memory for disgust. According to the memory consolidation mechanism, it is harder (but crucial) to remember potentially contaminating vs. threatening stimuli. Hence, disgust elicits additional memory consolidation processes to fear. According to the attention mechanism, it takes longer to establish if disgust (relative to fear) stimuli are dangerous. Hence, people pay more attention to disgust during encoding. Both mechanisms could boost memory for disgust. Ninety-eight participants encoded disgust, fear, and neutral images whilst completing a simple task to measure attention. After 10- or 45-min delay, participants freely recalled the images. We found enhanced memory for disgust relative to fear after 10- and 45-min delay, but this effect was larger after 45-min. Participants paid more attention to disgust than fear images during encoding. However, mixed effect models showed increased attention did not contribute to enhanced memory for disgust. Our results therefore support the memory consolidation mechanism.

In exogenous attention, time is the clue: Brain and heart interactions to survive threatening stimuli

The capture of exogenous attention by negative stimuli has been interpreted as adaptive for survival in a diverse and changing environment. In the present paper, we investigate the neural responses towards two discrete negative emotions with different biological meanings, disgust and fear, and its potential relationships with heart rate variability (HRV) as an index of emotional regulation. With that aim, 30 participants performed a digit categorization task while fear, disgust and neutral distractor pictures were presented. Resting HRV at baseline, behavioral responses, and event-related potentials were recorded. Whereas P1 amplitudes were highest to fear distractors, the disgust stimulation led to augmented P2 amplitudes compared to the rest of distractors. Interestingly, increased N2 amplitudes were also found to disgust distractors, but only in high HRV participants. Neural source estimation data point to the involvement of the insula in this exogenous attentional response to disgust. Additionally, disgust distractors provoked longer reaction times than fear and neutral distractors in the high HRV group. Present findings are interpreted in evolutionary terms suggesting that exogenous attention is captured by negative stimuli following a different time course for fear and disgust. Possible HRV influences on neural mechanisms underlying exogenous attention are discussed considering the potential important role of this variable in emotional regulation processes.

Underlying neurological mechanisms associated with symptomatic convergence insufficiency

Convergence insufficiency (CI) is the most common binocular vision problem, associated with blurred/double vision, headaches, and sore eyes that are exacerbated when doing prolonged near work, such as reading. The Convergence Insufficiency Neuro-mechanism Adult Population Study (NCT03593031) investigates the mechanistic neural differences between 50 binocularly normal controls (BNC) and 50 symptomatic CI participants by examining the fast and slow fusional disparity vergence systems. The fast fusional system is preprogrammed and is assessed with convergence peak velocity. The slow fusional system optimizes vergence effort and is assessed by measuring the phoria adaptation magnitude and rate. For the fast fusional system, significant differences are observed between the BNC and CI groups for convergence peak velocity, final position amplitude, and functional imaging activity within the secondary visual cortex, right cuneus, and oculomotor vermis. For the slow fusional system, the phoria adaptation magnitude and rate, and the medial cuneus functional activity, are significantly different between the groups. Significant correlations are observed between vergence peak velocity and right cuneus functional activity (p = 0.002) and the rate of phoria adaptation and medial cuneus functional activity (p = 0.02). These results map the brain-behavior of vergence. Future therapeutic interventions may consider implementing procedures that increase cuneus activity for this debilitating disorder.

MATTER in emotion research: Spanish standardization of an affective image set

Pictures with affective content have been widely used in the scientific study of emotions, from two main perspectives: on the one hand, dimensional theories claiming that affective experiences can be described according to a few fundamental dimensions such as valence and arousal, and on the other hand, discrete-category theories proposing the presence of a number of basic and universal emotions. Although it has been demonstrated that these two approaches are not mutually exclusive, the existing standardized affective picture databases have been created from the dimensional perspective, which has led to important gaps for research focused on discrete emotions. The present work introduces MATTER, a new database comprising 540 pictures depicting disgusting, fearful, neutral, erotic, mirthful and incongruent content, which provides normative values (total N = 368, mean = 120.47 ratings/picture) in valence and arousal dimensions, as well as in discrete affective (disgust, fear, erotica and mirth) and cognitive (incongruence and interest) features. A tentative classification into discrete categories is presented, and the physical properties of each picture are reported. Our findings suggest that MATTER constitutes a modern and suitable set of affective images including, for the first time, both mirth- and incongruence-related pictures. Additionally, it will enable the examination of affective and cognitive processes in fear/disgust and humor/incongruence fields.

Preparing for the Worst: Attention is Enhanced Prior to Any Upcoming Emotional or Neutral Stimulus

Do people allocate more or fewer attentional resources when preparing for negative emotional visual stimuli to appear? In three experiments (total N = 150), participants performed a change-detection task while expecting a neutral, threatening, disgusting, or joyful stimulus or no stimulus to appear at a fixed moment. Responses to an infrequent dot probe were faster when participants were expecting a distracting stimulus. Importantly, although only negative stimuli impaired change-detection performance, there was no difference between the preparation effect for threatening and neutral stimuli (Experiment 1) or disgusting and joyful stimuli (Experiment 3). The preparation effects were also unaffected by the participant's anxiety level. Experiment 2 confirmed that the threatening images affected performance when the dot probe appeared after the image. These results suggest that the visual system increases alertness in response to any upcoming stimulus and further imply that the effects of emotional stimuli largely occur after, but not before, the stimuli appear.

Understanding the capture of exogenous attention by disgusting and fearful stimuli: The role of interoceptive accuracy

The aim of the study was to explore the role of interoceptive accuracy (IA) on exogenous attention to disgusting and fearful distractors of a main concurrent task. Participants were thirty university students previously identified as high (N = 16) or normal IA according their performance in a heartbeat detection task. Event-related potentials and behavioural responses were recorded. The results showed that disgusting stimuli capture exogenous attention in a first stage as reflected by the augmented amplitude of the P100 component of the ERPs in high IA participants. Fearful distractors may capture attention in a later moment in all participants as revealed by a marginally significant effect on the amplitude of N200. At behavioural level, disgusting distractors provoked a higher number of errors than neutral in normal IA participants. The time course of the effect of disgust and fearful eliciting distractors on exogenous attention appeared to depend on the individual characteristic of participants.

Attentional Processing of Disgust and Fear and Its Relationship With Contamination-Based Obsessive-Compulsive Symptoms: Stronger Response Urgency to Disgusting Stimuli in Disgust-Prone Individuals

Disgust has recently been characterized as a low-urgency emotion, particularly compared to fear. The aim of the present study is to clarify whether behavioral inhibition during disgust engagement is characteristic of a low-urgency emotion and thus indicates self-imposed attentional avoidance in comparison to fear. Therefore, 54 healthy participants performed an emotional go/no-go task with disgust- and fear-relevant as well as neutral pictures. Furthermore, heart rate activity and facial muscle activity on the fear-specific m. corrugator supercilli and the disgust-specific m. levator labii were assessed. The results partially support the temporal urgency hypothesis of disgust. The emotion conditions significantly differed in emotional engagement and in the facial muscle activity of the m. levator labii as expected. However, contrary to our expectations, no differences between the emotion conditions regarding behavioral inhibition as well as heart rate change could be found. Furthermore, individuals with a higher-trait disgust proneness showed faster reactions and higher activity of the m. levator labii in response to disgust stimuli. The results show that different trait levels influence attentional engagement and physiological parameters but have only a small effect on behavioral inhibition.

Investigating the replicability and boundary conditions of the mnemonic advantage for disgust

Research has demonstrated that people remember emotional information better than neutral information. However, such research has almost exclusively defined emotion in terms of valence and arousal. Discrete emotions may affect memory above and beyond such dimensions, with recent research indicating that disgusting information is better remembered than frightening information. We initially sought to determine whether participants are sensitive to the effects of discrete emotions when predicting their future memory performance. Participants in Experiment 1 were more confident in their memory for emotional (both frightening and disgusting) images relative to neutral images, but confidence did not differ between frightening and disgusting images. However, because we did not replicate the mnemonic advantage of disgust, subsequent experiments were concerned with testing the replicability of this effect. Because metamemorial judgments sometimes eliminate memory effects, participants in Experiment 2 did not make such judgments. Even so, the effect did not replicate. The disgust advantage was ultimately replicated in Experiment 3, where participants completed a secondary task at encoding. The disgust advantage is replicable but appears less robust than previously recognised. A single-paper meta-analysis indicated that the effect is more likely under divided attention, perhaps because the mechanisms which mediate disgust-memory are relatively automatic.

The Influence of Discrete Negative and Positive Stimuli on Recognition Memory of Younger vs. Older Adults

Background: The effects of emotional stimuli on memory in older adults are often addressed in terms of socio-emotional selectivity theory and the valence dimension. Older adults usually remember positive stimuli better than negative stimuli. However, studies examining the effects of discrete emotions on the elderly are still limited. The present study examined the effects of negative and positive discrete emotions (fear, disgust, and happiness) on recognition memory of older and younger adults. Method: In the encoding phase, participants studied happiness-, disgust-, fear-, and neutral- related photos while doing a line discrimination task that assessed their attention. After 45 minutes, they completed an old/new recognition memory test on a confidence rating scale and also rated self-relevance of photos. Results: Younger participants showed a more liberal response bias for disgust- and fear-related stimuli, and were also more accurate in recognizing disgust-related photos compared to others. Older adults showed a more liberal bias only for disgust-related stimuli, however, their recognition accuracy did not differ across emotion categories. Conclusion: These results suggested that the effect of disgust-related stimuli on recognition memory may decrease with age and emotion effects cannot solely be accounted for by the valence/arousal dimensions.

Dispositional Self-Construal Modulates Neural Representation of Self: An ERP Study

This study aimed to investigate the influence of dispositional self-construal on self-related processing. Event-related potentials (ERPs) were recorded for a participant’s own and a famous person’s name in a three-stimulus oddball task. The results showed greater P2 and P3 amplitudes induced by one’s own than by a famous person’s name in both independent and interdependent self-construal groups. However, no N2 amplitude differences were found between the partcipant’s own name and a famous person’s name in either group. Moreover, the strength of the P2 effect (own vs. famous person’s name) was stronger in the independent than in the interdependent self-construal group, whereas the P3 effect was similar between these two groups. Thus, these findings might reflect fast modulation of self-related processing by dispositional self-construal.

Interpretation bias and contamination-based obsessive-compulsive symptoms influence emotional intensity related to disgust and fear

Biased processing of disgust-related stimuli is increasingly discussed in addition to fear-related processing as a maintenance factor for contamination-based obsessive-compulsive disorder (C-OCD). However, the differential impact of fear and disgust on biased processing in C-OCD is not yet completely understood. Because it is difficult to distinguish the two emotions in self-report assessment by directly addressing the specific emotions, a text paragraph-based interpretation bias paradigm was applied to more implicitly assess emotions. For the text-based interpretation bias paradigm, disgust-related, fear-related, disgust-fear-ambiguous and neutral text paragraphs describing everyday life situations were developed and validated in a pre-study (N = 205). Fifty-nine healthy participants watched either disgust- or fear-inducing movies and afterwards rated their experienced emotional response to the text paragraphs. The results show that fear and disgust components of an emotional response to mixed-emotional situations are strongly influenced by the situational context, and across the levels of trait contamination fear people did not differ in their fear experiences to everyday situations (which was overall strong), but in their disgust experiences. These findings highlight the strength of situational context on interpretation bias for mixed-emotional disorders and the important role of disgust for C-OCD.

Temporal features of individual and collective self-referential processing: an event-related potential study

Background

Individual and collective self are two fundamental self-representations and are important to human experience. The present study aimed to investigate whether individual and collective self have essential difference in neural mechanism.

Methods

Event-related potentials were recorded to explore the electrophysiological correlates of individual and collective self in a self-referential task in which participants were asked to evaluate whether trait adjectives were suitable to describe themselves (individual self-referential processing), a famous person (individual non-self-referential processing), Chinese (collective self-referential processing) or American (collective non-self-referential processing).

Results

At the early stages, results showed that larger P2 and smaller N2 amplitudes were elicited by individual self-referential than by individual non-self-referential processing whereas no significant differences were observed between collective self-referential and collective non-self-referential processing at these stages. In addition, at the late P3 stage (350–600 ms), larger P3 amplitudes were also elicited by individual self-referential than by individual non-self-referential processing during 350–600 ms interval. However, the collective self-reference effect, indicated by the differences between collective self-referential and collective non-self-referential processing, did not appear until 450 ms and extended to 600 ms. Moreover, individual self-reference effect was more pronounced than collective self-reference effect in the 350–500 ms interval, whereas individual and collective self-reference effect had no significant difference in the 500–600 ms interval. These findings indicated that the time courses of neural activities were different in processing individual and collective self.

Deconstructing threat: Rethinking the interplay between biological and social relevance in the emotional salience of unpleasant images

The type of threat shown in an image influences the emotional salience of unpleasant images. Seventy-four participants (21 male) rated high threat, moderate threat, and neutral images featuring reptiles, firearms, or humans as electroencephalographic activity was recorded. The magnitude of P3b amplitudes coincided with the threat level of firearm and human images, whereas scenes of attacking snakes and aimed handguns evoked more positive late positive component (LPC) activity than non-attacking or neutral versions of these same stimuli. The lateralised early posterior negativity (EPN) in temporal occipital regions was most negative for firearms, followed by reptiles, and then humans, while the midline EPN in occipital regions was most negative for reptiles, followed by firearms, and then humans. These findings imply late event-related potential positivity is influenced by social relevance (the P3b) or the level of aggression displayed by the stimulus (the LPC), whereas stimulus type may be indexed by EPN modulation.

Subliminal emotional pictures are capable of modulating early cerebral responses to pain in fibromyalgia

Pain experience involves a complex relationship between sensory and both emotional and cognitive factors, which appear to be mediated by different neural pathways. Previous evidence has shown that whereas conscious processing of unpleasant stimuli enhances pain perception, the influence of emotions on pain under unaware conditions is much less known. The need to better characterise the relationship between pain processing and emotional factors is crucial for dealing with chronic pain conditions. Therefore, the present study aimed to explore the neural correlates relating to the influence of visual masking emotional stimulation on the processing of painful stimuli in chronic pain patients suffering from fibromyalgia (FM). Twenty FM and 22 healthy control (HC) women participated in the study. The experimental masking paradigm consisted of a rapid succession of two types of stimuli, where a masked picture (neutral, negative or pain-related) was followed by a laser stimulus (painful or not painful). LEP activity was recorded at sixty scalp electrodes. An LEP-amplitude approach was used to quantify the main cerebral waves linked to pain response. ANOVAs indicated that the posterior regions of the P1 component were sensitive to experimental manipulation (p<0.05). Specifically, FM patients showed higher amplitudes to painful stimuli preceded by pain-related pictures compared with painful trials preceded by other emotional pictures. The FM group also showed greater amplitudes than those in the HC group in P2a and P2b waves. In addition to the scalp data, at the neural level the posterior cingulate cortex, lingual gyrus and insular cortex showed higher activation in the FM group than in the HC group. Our findings show an early cerebral modulation of pain (as reflected by the P1) in FM patients, suggesting that only pain-related information, even when it is unconsciously perceived, is capable to enhance exogenous (automatic) attention, increasing the neural activity involved in processing painful stimulation. Further research is needed to fully understand unconscious emotional influences on pain in fibromyalgia.

Distraction by deviant sounds: disgusting and neutral words capture attention to the same extent

Several studies have argued that words evoking negative emotions, such as disgust, grab attention more than neutral words, and leave traces in memory that are more persistent. However, these conclusions are typically based on tasks requiring participants to process the semantic content of these words in a voluntarily manner. We sought to compare the involuntary attention grabbing power of disgusting and neutral words using them as rare and unexpected auditory distractors in a cross-modal oddball task, and then probing the participants’ memory for these stimuli in a surprise recognition task. Frequentist and Bayesian analyses converged to show that, compared to a standard tone, disgusting and neutral auditory words produced significant but equivalent levels of distraction in a visual categorization task, that they elicited comparable levels of memory discriminability in the incidental recognition task, and that the participants’ individual sensitivity to disgust did not influence the results. Our results suggest that distraction by unexpected words is not modulated by their emotional valence, at least when these words are task-irrelevant and are temporally and perceptually decoupled from the target stimuli.

Fronto-central P3a to distracting sounds: An index of their arousing properties

The P3a observed after novel events is an event-related potential comprising an early fronto-central phase and a late fronto-parietal phase. It has classically been considered to reflect the attention processing of distracting stimuli. However, novel sounds can lead to behavioral facilitation as much as behavioral distraction. This illustrates the duality of the orienting response which includes both an attentional and an arousal component. Using a paradigm with visual or auditory targets to detect and irrelevant unexpected distracting sounds to ignore, we showed that the facilitation effect by distracting sounds is independent of the target modality and endures more than 1500 ms. These results confirm that the behavioral facilitation observed after distracting sounds is related to an increase in unspecific phasic arousal on top of the attentional capture. Moreover, the amplitude of the early phase of the P3a to distracting sounds positively correlated with subjective arousal ratings, contrary to other event-related potentials. We propose that the fronto-central early phase of the P3a would index the arousing properties of distracting sounds and would be linked to the arousal component of the orienting response. Finally, we discuss the relevance of the P3a as a marker of distraction.

Individual Differences in Attentional Capture by Pictures of Fear and Disgust as Indexed by Cardiac Responses

Abstract. Emotional stimuli automatically capture attention in ways that are relevant to the survival value of the stimuli. We have previously shown that individual differences in resting heart rate variability (HRV) were related to attentional capture by negative (fearful) and neutral distractors. However, different negative emotions such as fear and disgust may differentially capture attention. In the present study we investigated the effect of automatic attention capture by disgust and fear stimuli on behavioral and phasic heart rate responses as well as its relationship with resting heart rate variability (HRV). Twenty-eight participants (14 men) were divided into two groups based on their resting HRV. Phasic cardiac responses as well as reaction times and errors on a digit categorization task were assessed with disgust, fear, and neutral pictures as distractors. In the high HRV group disgusting distractors produced the strongest interference on the ongoing cognitive task indicated by more errors and longer reaction times as well as a deeper cardiac deceleration compared to fearful or neutral distractors. In contrast, the low HRV group showed faster reaction times to fear evoking pictures, whereas their heart rate responses and number of errors did not distinguish between the three emotional categories. Our results suggest that high HRV participants showed the emotional context appropriate responses while low HRV participants seem to be hypervigilant to fear.

Fractal dimension of EEG signals and heart dynamics in discrete emotional states

In this study, we explored the fractal dimension (FD; a measure of signal complexity) of 28 EEG channels with positive and negative emotional states. The EEG of participants and their ECG were registered while watching short video clips that induced fear, disgust, humour, or neutral emotions. In order to better understand the nature of these emotions, the Higuchi FD of EEG segments and the heart rate variability (HRV) of the ECG associated with each emotion were obtained. Our results exhibited similar patterns of results with both measures. Humour elicited the highest FD scores in most EEG channels and the highest HRV, while fear, among all emotions, produced the lowest scores in both measures. These results may contribute to the understanding of the relationship between cortical and heart dynamics and their role on emotion perception.

Cognitive mechanisms of disgust in the development and maintenance of psychopathology: A qualitative review and synthesis

A growing body of research has implicated disgust in various psychopathologies, especially anxiety-related disorders. Although the observed role of disgust in many disorders is robust, the mechanisms that may explain this role are unclear. Cutting-edge research in cognitive science has the potential to elucidate such mechanisms and consequently improve our understanding of how disgust contributes to the etiology and maintenance of psychopathology. In this qualitative review, we systematically assess cognitive bias mechanisms that have been linked to disgust and its disorders. This review suggests that disgust-related biases may be observed in memory, interpretation, judgment of expectancies, and attention, as well as at implicit levels. Of these cognitive domains, the most robust bias appears to be observed at the level of attention. However, reliable moderators of attentional biases for disgust have not yet been identified, and this bias has not been systematically linked to other levels of analysis. Despite these limitations, the available research indicates that attentional avoidance rather than orienting or maintenance may be the most characteristic of disgust. Attentional avoidance of disgust may have important implications for etiological and treatment models of disorders characterized by excessive disgust reactions. The implications for advancing such models are discussed in the context of a combined cognitive bias hypothesis.

Examination of Responses Involved in Contamination Aversion Based on Threat Type

There is evidence that different types of contaminants produce different responses and have different motivations for avoidance. Contaminants directly associated with disease (direct contaminants) are motivated by disgust avoidance, whereas contaminants indirectly associated with disease (indirect contaminants) and contaminants associated with harmful substances (harm contaminants) are motivated by harm avoidance and threat estimations. This study aims to confirm this distinction between contaminant types and examine the role of cognitive load, awareness and time on processing these threats. One hundred and four participants completed three chain of contagion tasks with direct, indirect, and harm contaminants. Cognitive load, awareness of contamination and time were manipulated during the tasks. Consistent with previous findings, direct contaminants produced stronger disgust responses, while harm and indirect contaminants produced stronger threat estimations. Increasing cognitive load did not impact processing of any type of contaminant. There was evidence that a time delay reduced the spread of contagion for all contaminants. This highlights the importance of time in altering the perception of contamination threat. Implications and future research directions are discussed.

Differential response patterns to disgust-related pictures

In the present study, attentional bias was investigated as a potential predisposing mechanism for the contamination-related subtype of obsessive-compulsive disorder (C-OC disorder). Fifty healthy participants with varying degrees of subclinical C-OC symptoms performed a visual search task to measure differential attentional biases elicited by neutral, disgust-, and fear-specific pictorial material. Participants had to find a target picture within five neutral distractor pictures randomly presented on different locations in an array. The task was to decide whether the array contained an unpleasant target picture or not. In randomly-selected emotional trials, participants were further asked about the content of the picture and the confidence of their answer. The results show that the reaction times significantly differed between the emotional and neutral pictures. Participants were significantly more confident in answering questions referring to fear compared to disgust pictures. This effect was marginally amplified in participants with higher C-OC symptoms. We discuss the results within the framework of the cost and benefit hypothesis, which postulates that disgust evolutionarily elicits stronger uncertainty compared to fear, owing to the ambiguous nature of the stimuli. Increased uncertainty might be an important but underestimated factor for pathological disgust experience, such as in obsessive-compulsive disorder.

The influence of affective state on exogenous attention to emotional distractors: behavioral and electrophysiological correlates

The interplay between exogenous attention to emotional distractors and the baseline affective state has not been well established yet. The present study aimed to explore this issue through behavioral measures and event-related potentials (ERPs). Participants (N = 30) completed a digit categorization task depicted over negative, positive or neutral distractor background pictures, while they experienced negative, positive and neutral affective states elicited by movie scenes. Behavioral results showed higher error rates and longer reaction times for negative distractors than for neutral and positive ones, irrespective of the current emotional state. Neural indices showed that the participants' affective state modulated N1 amplitudes, irrespective of distractor type, while the emotional charge of distractors modulated N2, irrespective of the emotional state. Importantly, an interaction of state and distractor type was observed in LPP. These results demonstrate that exogenous attention to emotional distractors is independent from modulating effects of the emotional baseline state at early, automatic stages of processing. However, attention to emotional distractors and affective state interact at later latencies.

Neural Process of the Preference Cross-category Transfer Effect: Evidence from an Event-related Potential Study

In business practice, companies prefer to find highly attractive commercial spokesmen to represent and promote their products and brands. This study mainly focused on the investigation of whether female facial attractiveness influenced the preference attitudes of male subjects toward a no-named and unfamiliar logo and determined the underlying reasons via neuroscientific methods. We designed two ERP (event-related potential) experiments. Experiment 1 comprised a formal experiment with facial stimuli. The purpose of experiment 2 was to confirm whether the logos that were used did not present a significant difference for the subjects. According to the behavioural results of experiment 1, when other conditions were not significantly different, the preference degree of the logos correlated with attractive female faces was increased compared with the logos correlated with unattractive faces. Reasons to explain these behavioural phenomena were identified via ERP measures, and preference cross-category transfer mainly caused the results. Additionally, the preference developed associated with emotion. This study is the first to report a novel concept referred to as the “Preference Cross-Category Transfer Effect”. Moreover, a three-phase neural process of the face evaluation subsequently explained how the cross-category transfer of preference occurred and influenced subject preference attitude toward brand logos.

Decreased Pain Perception by Unconscious Emotional Pictures

Pain perception arises from a complex interaction between a nociceptive stimulus and different emotional and cognitive factors, which appear to be mediated by both automatic and controlled systems. Previous evidence has shown that whereas conscious processing of unpleasant stimuli enhances pain perception, emotional influences on pain under unaware conditions are much less known. The aim of the present study was to investigate the modulation of pain perception by unconscious emotional pictures through an emotional masking paradigm. Two kinds of both somatosensory (painful and non-painful) and emotional stimulation (negative and neutral pictures) were employed. Fifty pain-free participants were asked to rate the perception of pain they were feeling in response to laser-induced somatosensory stimuli as faster as they can. Data from pain intensity and reaction times were measured. Statistical analyses revealed a significant effect for the interaction between pain and emotional stimulation, but surprisingly this relationship was opposite to expected. In particular, lower pain intensity scores and longer reaction times were found in response to negative images being strengthened this effect for painful stimulation. Present findings suggest a clear pain perception modulation by unconscious emotional contexts. Attentional capture mechanisms triggered by unaware negative stimulation could explain this phenomenon leading to a withdrawal of processing resources from pain.