Negative mood state enhances the susceptibility to unpleasant events: neural correlates from a music-primed emotion classification task

Effect of Taste-Induced Mood on ERP and Emotional Assessment of Images

Tastes affect the body and our emotions. We used tasteless, sweet, and bitter stimuli to induce participants' moods, and we examined the effect of mood on an emotional evaluation of pleasant, neutral, and unpleasant images using event-related potentials, N2, N400, and late positive potential (LPP), which reflect emotional evaluation in the brain. The results indicated that mood valence was most positive for sweetness and most negative for bitterness. Moreover, there was no significant mood effect on subjective valence ratings of emotional images. Furthermore, the N2 amplitude, which is related to the early semantic processing of preceding stimuli, was unaffected by the taste induced mood. In contrast, we found that the N400 amplitude, which is related to the mismatch of emotional valence between stimuli, increased significantly for unpleasant images when participants were in a positive rather than negative mood state. Also, the LPP amplitude, which is related to the emotional valence of images, showed only the main effect of the images' emotional valence. The N2's results suggest that the early semantic processing of taste stimuli might have had a negligible impact on emotional evaluation because taste stimuli minimize semantic processing that accompanies mood induction. In contrast, the N400 reflected the effects of the induced mood, and the LPP reflected the impact of the valence of emotional images. The use of taste stimuli to induce mood revealed different brain processing of taste-induced mood effects on emotional evaluation, including N2's involvement in semantic processing, N400's involvement in matching emotions between mood and stimuli, and LPP's involvement in subjective evaluations of stimuli.

Exogenous Attention to Emotional Stimuli Presenting Realistic (3D) Looming Motion

Previous research shows that dynamic stimuli, on the one hand, and emotional stimuli, on the other, capture exogenous attention due to their biological relevance. Through neural (ERPs) and behavioral measures (reaction times and errors), the present study explored the combined effect of looming motion and emotional content on attentional capture. To this end, 3D-recreated static and dynamic animals assessed as emotional (positive or negative) or neutral were presented as distractors while 71 volunteers performed a line orientation task. We observed a two-phase effect: firstly (before 300 ms), early components of ERPs (P1p and N2po) showed enhanced exogenous attentional capture by looming positive distractors and static threatening animals. Thereafter, dynamic and static threatening distractors received enhanced endogenous attention as revealed by both late ERP activity (LPC) and behavioral (errors) responses. These effects are likely explained by both the emotional valence and the distance of the stimulus at each moment.

Realistic (3D) looming of emotional visual stimuli: Attentional effects at neural and behavioral levels

Previous research shows that endogenous attention (the controlled selection of certain aspects of our environment) is enhanced toward emotional stimuli due to its biological relevance. Although looming affective stimuli such as threat seem even more critical for survival, little is known about their effect on endogenous attention. Here, we recorded neural (event-related potentials, ERPs) and behavioral responses (errors and reaction times) to explore the combined effect of emotion and looming motion. 3D-recreated static and moving animals assessed as emotionally positive, negative, and neutral, were presented to participants (n = 71), who performed an indirect categorization task (vertebrate vs. invertebrate). Behavioral results showed better task performance, as reflected by lower number of errors and reaction times, in response to threatening stimuli. Neural indices revealed significant early (P1p, 150 milliseconds), intermediate (P2p, 240), and late (LPP, 450) effects, the latter being more intensely associated with behavior, as revealed by regression analyses. In general, neural indexes of attention to both static and dynamic stimuli showed a positivity offset in early stages and a negativity bias in subsequent phases. However, and importantly, the progressive inclusion of negative stimuli in the attentional focus is produced earlier in the case of dynamic (at P2p latency) than in static versions (at LPP). These results point to an enhancement of attention, particularly in temporal terms, toward stimuli combining motion and biological significance.

The Childhood Maltreatment Modulates the Impact of Negative Emotional Stimuli on Conflict Resolution

It has been reported that negative emotional stimuli could facilitate conflict resolution. However, it remains unclear about whether and how the impact of negative emotional stimuli on conflict resolution varies depending on childhood maltreatment. To clarify this issue, seventy-nine subjects were required to perform an arrow Eriksen Flanker Task which was presented in the center of emotional pictures. The present study found a significant interaction effect of childhood maltreatment and emotion on executive attention scores in reaction times (RTs) that reflect conflict resolution speed. For subjects in high childhood maltreatment, negative pictures elicited smaller executive attention scores in RTs than neutral and positive pictures, while neutral and positive pictures elicited similar executive attention scores in RTs. By contrast, for subjects in low childhood maltreatment, executive attention scores in RTs were similar across three conditions. These results suggest that the speed of conflict resolution is enhanced in high, instead of low, childhood maltreatment in situations of negative stimuli. This finding extends our understanding of the interaction among emotion, childhood maltreatment and conflict resolution.

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.

The impact of mood on empathy for pain: Evidence from an EEG study

The current work investigated whether the neural correlates of empathy for pain are altered by mood valence of observers. Following mood induction, participants watched pictures representing painful or nonpainful situations. We used EEG to record neural activity and assessed event-related desynchronization at central sites during pain observation. Greater mu desynchronization was observed during painful relative to nonpainful situations in positive and neutral mood but not in negative mood. We also found that the pain empathy effect, indexed by mu suppression differences between painful and nonpainful conditions, was smaller in negative than in neutral and positive mood, while this effect was similar between neutral and positive mood. The current study demonstrates that observers' mood states influence the motoric component of empathy for pain, and specifically the negative mood suppresses the motoric empathic resonance for others' pain.

The neural mechanisms underlying the aging-related enhancement of positive affects: electrophysiological evidences

Background: Previous studies reported that old adults, relative to young adults, showed improvement of emotional stability and increased experiences of positive affects.

Methods: In order to better understand the neural underpinnings behind the aging-related enhancement of positive affects, it is necessary to investigate whether old and young adults differ in the threshold of eliciting positive or negative emotional reactions. However, no studies have examined emotional reaction differences between old and young adults by manipulating the intensity of emotional stimuli to date. To clarify this issue, the present study examined the impact of aging on the brain’s susceptibility to affective pictures of varying emotional intensities. We recorded event-related potentials (ERP) for highly negative (HN), mildly negative (MN) and neutral pictures in the negative experimental block; and for highly positive (HP), mildly positive (MP) and neutral pictures in the positive experimental block, when young and old adults were required to count the number of pictures, irrespective of the emotionality of the pictures.

Results: Event-related potentials results showed that LPP (late positive potentials) amplitudes were larger for HN and MN stimuli compared to neutral stimuli in young adults, but not in old adults. By contrast, old adults displayed larger LPP amplitudes for HP and MP relative to neutral stimuli, while these effects were absent for young adults. In addition, old adults reported more frequent perception of positive stimuli and less frequent perception of negative stimuli than young adults. The post-experiment stimulus assessment showed more positive ratings of Neutral and MP stimuli, and reduced arousal ratings of HN stimuli in old compared to young adults.

Conclusion: These results suggest that old adults are more resistant to the impact of negative stimuli, while they are equipped with enhanced attentional bias for positive stimuli. The implications of these results to the aging-related enhancement of positive affects were discussed.

The time course of emotional picture processing: an event-related potential study using a rapid serial visual presentation paradigm

The present study recorded event-related potentials using rapid serial visual presentation paradigm to explore the time course of emotionally charged pictures. Participants completed a dual-target task as quickly and accurately as possible, in which they were asked to judge the gender of the person depicted (task 1) and the valence (positive, neutral, or negative) of the given picture (task 2). The results showed that the amplitudes of the P2 component were larger for emotional pictures than they were for neutral pictures, and this finding represents brain processes that distinguish emotional stimuli from non-emotional stimuli. Furthermore, positive, neutral, and negative pictures elicited late positive potentials with different amplitudes, implying that the differences between emotions are recognized. Additionally, the time course for emotional picture processing was consistent with the latter two stages of a three-stage model derived from studies on emotional facial expression processing and emotional adjective processing. The results of the present study indicate that in the three-stage model of emotion processing, the middle and late stages are more universal and stable, and thus occur at similar time points when using different stimuli (faces, words, or scenes).

Different timing features in brain processing of core and moral disgust pictures: an event-related potentials study

Disgust, an emotion motivating withdrawal from offensive stimuli, protects us from the risk of biological pathogens and sociomoral violations. Homogeneity of its two types, namely, core and moral disgust has been under intensive debate. To examine the dynamic relationship between them, we recorded event-related potentials (ERPs) for core disgust, moral disgust and neutral pictures while participants performed a modified oddball task. ERP analysis revealed that N1 and P2 amplitudes were largest for the core disgust pictures, indicating automatic processing of the core disgust-evoking pictures. N2 amplitudes were higher for pictures evoking moral disgust relative to core disgust and neutral pictures, reflecting a violation of social norms. The core disgust pictures elicited larger P3 and late positive potential (LPP) amplitudes in comparison with the moral disgust pictures which, in turn, elicited larger P3 and LPP amplitudes when compared to the neutral pictures. Taken together, these findings indicated that core and moral disgust pictures elicited different neural activities at various stages of information processing, which provided supporting evidence for the heterogeneity of disgust.

Suppression dampens unpleasant emotion faster than reappraisal: Neural dynamics in a Chinese sample

The timing dynamics of regulating negative emotion with expressive suppression and cognitive reappraisal were investigated in a Chinese sample. Event-Related Potentials were recorded while subjects were required to view, suppress emotion expression to, or reappraise emotional pictures. The results showed a similar reduction in self-reported negative emotion during both strategies. Additionally, expressive suppression elicited larger amplitudes than reappraisal in central-frontal P3 component (340-480 ms). More importantly, the Late Positive Potential (LPP) amplitudes were decreased in each 200 ms of the 800-1600 ms time intervals during suppression vs. viewing conditions. In contrast, LPP amplitudes were similar for reappraisal and viewing conditions in all the time windows, except for the decreased amplitudes during reappraisal in the 1400-1600 ms. The LPP (but not P3) amplitudes were positively related to negative mood ratings, whereas the amplitudes of P3, rather than LPP, predict self-reported expressive suppression. These results suggest that expressive suppression decreases emotion responding more rapidly than reappraisal, at the cost of greater cognitive resource involvements in Chinese individuals.

Feedback-related negativity in children with two subtypes of attention deficit hyperactivity disorder

OBJECTIVE

The current model of ADHD suggests abnormal reward and punishment sensitivity, although differences in ADHD subgroups are unclear. This study aimed to investigate the effect of feedback valence (reward or punishment) and punishment magnitude (small or large) on Feedback-Related Negativity (FRN) and Late Positive Potential (LPP) in two subtypes of ADHD (ADHD-C and ADHD-I) compared to typically developing children (TD) during a children's gambling task.

METHODS

Children with ADHD-C (n = 16), children with ADHD-I (n = 15) and typically developing children (n = 15) performed a children's gambling task under three feedback conditions: large losses, small losses and gains. FRN and LPP components in brain potentials were recorded and analyzed.

RESULTS

In TD children and children with ADHD-C, large loss feedback evoked more negative FRN amplitudes than small loss feedback, suggesting that brain sensitivity to the punishment and its magnitude is not impaired in children with ADHD-C. In contrast to these two groups, the FRN effect was absent in children with ADHD-I. The LPP amplitudes were larger in children with ADHD-C in comparison with those with ADHD-I, regardless of feedback valence and magnitude.

CONCLUSION

Children with ADHD-C exhibit intact brain sensitivity to punishment similar to TD children. In contrast, children with ADHD-I are significantly impaired in neural sensitivity to the feedback stimuli and in particular, to punishment, compared to TD and ADHD-C children. Thus, FRN, rather than LPP, is a reliable index of the difference in reward and punishment sensitivity across different ADHD-subcategories.