The medial frontal cortex and the rapid processing of monetary gains and losses

Deconstructing Temporal Stages of Prosocial and Antisocial Risky Decision-making in Adolescence

Risk-taking is a prominent aspect of adolescent behavior. A recent neurodevelopmental model suggests that this trait could influence prosocial and antisocial decision-making, proposing a new category known as prosocial and antisocial risk-taking. The primary objective of this study was to examine the electrophysiological underpinnings of prosocial and antisocial risk-taking in adolescence, a developmental period characterized by elevated risky, prosocial, and antisocial decisions. To this end, 32 adolescents aged 13-19 years completed a modified dictator game to choose between three options, representing prosocial and antisocial risk-taking constructs and a risk-free fair one. At the behavioral level, adolescents favored antisocial risky decisions over prosocial risky ones. ERP results at the electrophysiological level in the response selection stage demonstrated that decision preceding negativity was more negative-going before making prosocial risky decisions than other decisions. During the feedback evaluation stage, feedback-related negativity was the least negative after selecting the antisocial risky option and receiving successful feedback. However, choosing the fair option and receiving neutral feedback resulted in the most negative feedback-related negativity. Moreover, P300 showed the most positive mean amplitude following the selection of the antisocial risky option and facing successful feedback, with the lowest positive amplitude observed after choosing the fair option and encountering neutral feedback. These results underscore the distinct electrophysiological underpinnings associated with prosocial and antisocial decisions involving risks.

Does outcome feedback similarly impact the processing of surprised faces in competitive and cooperative contexts? Evidence from ERP

Competition and cooperation are pervasive across diverse domains of human society, and outcome feedback in these contexts has been shown to significantly influence human emotional responses and behavioral strategies. However, there is limited understanding of the mechanisms through which outcome feedback in obstructive and supportive settings affects the perception of facial expressions of interactors. To address this issue, thirty-seven participants in this event-related potential (ERP) study completed a modified version of the Tetris game with randomly assigned interactors (cooperative supporter, competitive hinderer). After receiving outcome feedback (correct, incorrect), participants were asked to rate the valence of surprised faces which were assumed to be displayed by interactors. Behaviorally, surprised faces in supportive correct feedback contexts were rated as more pleasant, while those in obstructive correct feedback contexts were rated as less pleasant. The ERP results showed a significant main effect of outcome feedback on the FRN and LPPfeedback, with enhanced amplitudes for incorrect relative to correct trials. More importantly, face-related P1, N170, and EPN components showed significant interactions between interaction type and outcome feedback. Surprised faces in obstructive correct contexts evoked larger P1 amplitudes compared to those faces in obstructive incorrect contexts. Conversely, amplified N170 and EPN responses were observed for faces in supportive correct contexts compared to those in supportive incorrect contexts. For the LPPface, an amplified response to faces was observed in correct feedback contexts compared to incorrect ones, irrespective of the influence of interaction type. Altogether, these findings offer the first empirical evidence that feedback cues in obstructive and supportive contexts can interactively influence the top-down processing of facial expressions, shifting attention away from the suppression of aversive stimuli towards a focus on self-related positive information, thus providing insights into the neurocognitive mechanisms underlying the impact of complex social information on higher-order cognitive processes.

A measure of event-related potentials (ERP) indices of motivation during cycling

Although motivation is a central aspect of the practice of a physical activity, it is a challenging endeavour to predict an individual's level of motivation during the activity. The objective of this study was to assess the feasibility of measuring motivation through brain recording methods during physical activity, with a specific focus on cycling. The experiment employed the Effort Expenditure for Reward Task (EEfRT), a decision-making task based on effort and reward, conducted under two conditions: one involving cycling on an ergometer at moderate intensity and the other without cycling. The P300, an event-related potential linked to motivation, was recorded using electroencephalography. A total of 20 participants were recruited to complete the EEfRT, which involved making effort-based decisions of increasing difficulty in order to receive varying levels of monetary reward. The results demonstrated that the P300 amplitude was influenced by the act of cycling, exhibiting a reduction during the cycling session. This reduction may be explained by a reallocation of cognitive resources due to the exertion of physical effort, which is consistent with the transient hypofrontality theory. In terms of behaviour, participants demonstrated a tendency to make more challenging choices when the potential rewards were higher or the probability of gaining them was lower. This pattern was observed in both the cycling and non-cycling conditions. A positive correlation was identified between P300 amplitude and the proportion of difficult choices, particularly under conditions of low reward probability. This suggests that P300 may serve as a neural marker of motivation. The study demonstrates the feasibility of using electroencephalography to monitor motivation during exercise in real-time, with potential applications in rehabilitation settings. However, further research is required to refine the design and explore the effects of different exercise types on motivation.

Neural Response to Reward and Loss Following Basic Combat Training

BACKGROUND

The brain's responsiveness to rewarding stimuli is essential for adaptive functioning while deficits in neural reward processing have been linked to the transdiagnostic symptom of anhedonia. Acute or prolonged stressors may negatively impact neural reward responses; however, few studies have examined if real-world naturalistic stressors prospectively predict reductions in brain responses to rewards.

METHODS

This pre-registered analysis (https://osf.io/f6e8w) used data from the ARMOR study to assess whether exposure to basic combat training (BCT), a demanding and stress-inducing 10-week program, led to reductions in electrophysiological measures of reward response. One hundred sixteen military recruits completed a virtual gambling task while electroencephalogram (EEG) was recorded before and after BCT. Mean EEG activity in the time window of the Reward Positivity (RewP; 175 - 325ms post-feedback at FCz) was averaged separately for the gain and loss condition.

RESULTS

We found that neural response to both gain and loss feedback in the time-window of the RewP significantly decreased from baseline following BCT (b = -0.67, p <.001), but the difference between conditions did not (b = 0.28, p = .23). Greater reports of BCT-related stressors predicted decreased neural response to gain, but not loss. Finally, baseline reward-related power in the delta-band frequency prospectively predicted less self-reported BCT-related stress.

CONCLUSIONS

These findings suggest that experiencing the stress of BCT is associated with reductions in neural processing of both reward and loss feedback. Further, those with greater reward-related delta oscillatory activity may perceive less negative impact of real-world stressors.

Altruistic or fair? The influence of empathy on third-party punishment: an event-related potential study

Although most individuals strongly prefer social fairness and punish behaviours that violate fairness norms, recent psychological studies have shown that empathy towards 'perpetrators' who violate fairness norms can affect people's fairness decision-making, resulting in tolerance for unfair behaviour, even as direct 'victims' of unfair behaviour. However, in real life, people more often view unfair events from a third-party perspective, and little is known about how empathy affects fairness decisions by third parties whose self-interests are not threatened and their neurocognitive mechanisms. The present study examined effects of empathy directed towards a 'perpetrator' on third-party punishment using event-related potentials. The results suggest that, in the nonempathy condition, unfair offers induced stronger unfairness aversion in third-party decision makers and increased motivation and cognitive resource investment to alleviate this negative emotion compared to fair offers, reflecting the greater amplitude differences of fairness effects on the anterior N1 component, medial frontal negative, and smaller late positive components in the nonempathy condition. However, in the empathy condition, the differential impact of the fairness effect disappeared. These findings reveal the neural basis for trade-offs between altruistic and fairness motives in third-party fairness decision-making processes involving empathy.

Pathophysiological changes in incentive processing in episodic migraine: a preliminary event-related potential study

This study examined pathophysiological changes in incentive processing in migraineurs. Nineteen episodic migraine (EM) patients and 19 healthy controls (HCs) performed a monetary incentive delay task while their event-related potentials were recorded. During the incentive anticipation phase, both Cue-N2 and Cue-P3 amplitudes were responsive to incentive cues in both groups, indicating no between-group differences in the distinct anticipatory subprocesses that underly incentive cue evaluation. During the outcome phase, the feedback-related negativity amplitude, associated with performance evaluation, was larger for punishing feedback than rewarding feedback across both groups. However, the feedback-P3 amplitude, linked to attentional processing of motivational value of outcome feedback, was significantly larger for rewarding feedback than punishing feedback in HCs, but not in EM patients. Moreover, a significant negative correlation was observed between the feedback-P3 amplitude difference for rewarding minus punishing feedback and subjective pain intensity in EM patients. Finally, the feedback late-positive potential amplitude, related to affective processing of affective value of outcome feedback, was significantly larger for punishing feedback than rewarding feedback only in HCs, but not in EM patients. Our findings suggest that recurrent severe pain may relate to abnormal incentive-related brain activity during the outcome phase of incentive processing.

Reduced Sensitivity to Negative Feedback May Lead to Risky Decision-Making in Amphetamine Users

In Taiwan, amphetamines are the main drug of abuse. While drug abuse is often related to individual risky decision-making, how this relates to underlying neural mechanisms in amphetamine abusers remains unclear. The current study was carried out to help better understand this. A Balloon Analogue Risk Task (BART) was used to examine individual risky decision-making in conjunction with event-related potential (ERP) recording and presentation of questionnaires relating to behavioural control. Compared with healthy controls, amphetamine users had a lower score on the Behavioural Inhibition System (BIS) scale and showed reduced amplitudes in feedback-related negativity (FRN) and error-related negativity (ERN) ERP components following negative feedback on the task. Amphetamine users were less sensitive to punitive or aversive stimuli. This reduced sensitivity might lead to a higher tendency for risky decision-making, with them less able to learn from mistakes and thus repeatedly engage in risky behaviours.

The influence of empathic concern on evaluative processing in self and charity outcomes

Empathy plays a crucial role in determining how one understands others' emotional experiences and behavioral decisions. This study aimed to explore whether empathic concern affects the processing of self-related and charity-related outcome evaluations. In this study, participants performed gambling tasks for themselves and low- and high-empathy charities. The behavioral results showed that low-empathy charities had a significantly higher risk rate than the self, whereas there was no significant difference between low-and high-empathy charities. The event-related potential (ERP) results showed that the P300 valence difference (d-P300) of the self was significantly higher for high-empathy charitable activities than for low-empathy charitable activities, and the d-P300 of high-empathy charitable activities was significantly higher than that of low-empathy charitable activities. The P300 valence differences primarily originated from activation difference in the posterior mid-cingulate cortex (pMCC) and medial prefrontal cortex (mPFC). The time-frequency analysis showed that positive outcomes induced greater β2 event-related desynchronization (ERD) amplitudes for high-empathy charitable activities compared to negative outcomes. These findings suggest that empathic concern increased the distinction between good and bad outcomes for charities and promoted greater cognitive effort allocation toward prosocial rewards. The d-P300 is closely linked to activations in the pMCC and mPFC.

Climate trauma from wildfire exposure impacts cognitive decision-making

Climate trauma refers to the chronic mental health sequalae of climate disaster events. We have previously shown evidence for such trauma with accompanying anxiety and depression symptoms after California's 2018 Camp Fire wildfire. Here, we investigate whether this climate trauma also impacts cognitive decision-making and its neural correlates. One year after the wildfire, we recruited three groups - those directly exposed (n = 27), indirectly exposed (community members who witnessed the wildfire but not directly exposed, n = 21), versus non-exposed controls (n = 27). Participants performed a decision-making task that led to immediate and cumulative point rewards on each trial with simultaneous electroencephalography (EEG) recordings. We evaluated Win-Stay behavior in choosing to stay with the greater expected value (cumulative reward) option. Directly-exposed individuals showed significantly reduced Win-Stay behavior relative to the other groups. EEG analyses showed significantly greater parietal alpha activity for the selected choice and ensuing rewards in directly fire-exposed individuals, with an underlying cortical source of this activity in posterior cingulate cortex. Overall, these findings suggest that climate trauma may significantly impact neuro-cognitive processing in the context of value-based decision-making, which may serve as a useful biomarker target for future mental health interventions in climate change impacted communities.

Post-loss speeding and neurophysiological markers of action preparation and outcome processing in probabilistic reversal learning

Losses and errors often slow down subsequent reaction times (RTs). This is classically explained in terms of a shift towards more cautious, therefore slow, behaviour. Recent studies of gambling, however, reported faster RTs following losses, so-called post-loss speeding, often attributing these to behavioural impulsivity arising from frustration. Here we instead investigated post-loss speeding in the context of a task that allowed behavioural adaptation and learning, namely probabilistic reversal learning (PRL). We additionally used electroencephalography (EEG) to investigate how losses influence subsequent markers of action generation (readiness potential [RP]) and outcome evaluation (feedback-related negativity [FRN] and P300). Our results confirm faster RTs after losses than after wins in PRL, thus extending post-loss speeding from gambling to cognitive contexts where learning is possible. Previous losses did not affect subsequent RP amplitudes. However, compared to wins, previous losses led to more positive FRN and more positive P300 amplitudes elicited by subsequent outcomes. Furthermore, faster RTs were associated with more negative FRN amplitudes irrespective of previous or outcome valence. We hypothesise that post-loss speeding in PRL may represent a form of signal chasing, allowing participants to behaviourally modulate neurophysiological responses and thereby potentially establish agency by influencing internal neurophysiological signals.

Neural Reinforcement Learning Signals Predict Recovery From Impulse Control Disorder Symptoms in Parkinson's Disease

BACKGROUND

Impulse control disorders (ICDs) in Parkinson's disease are associated with a heavy burden on patients and caretakers. While recovery can occur, ICDs persist in many patients despite optimal management. The basis for this interindividual variability in recovery is unclear and poses a major challenge to personalized health care.

METHODS

We adopted a computational psychiatry approach and leveraged the longitudinal, prospective Personalized Parkinson Project (136 people with Parkinson's disease, within 5 years of diagnosis) to combine dopaminergic learning theory-informed functional magnetic resonance imaging with machine learning (at baseline) to predict ICD symptom recovery after 2 years of follow-up. We focused on change in Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease Rating Scale scores in the entire sample regardless of an ICD diagnosis.

RESULTS

Greater reinforcement learning signals during gain trials but not loss trials at baseline, including those in the ventral striatum and medial prefrontal cortex, and the behavioral accuracy score measured while on medication were associated with greater recovery from impulse control symptoms 2 years later. These signals accounted for a unique proportion of the relevant variability over and above that explained by other known factors, such as decreases in dopamine agonist use.

CONCLUSIONS

Our results provide a proof of principle for combining generative model-based inference of latent learning processes with machine learning-based predictive modeling of variability in clinical symptom recovery trajectories. We showed that reinforcement learning modeling parameters predicted recovery from ICD symptoms in Parkinson's disease.

Moral conviction interacts with metacognitive ability in modulating neural activity during sociopolitical decision-making

The extent to which a belief is rooted in one's sense of morality has significant societal implications. While moral conviction can inspire positive collective action, it can also prompt dogmatism, intolerance, and societal divisions. Research in social psychology has documented the functional characteristics of moral conviction and shows that poor metacognition exacerbates its negative outcomes. However, the cognitive and neural mechanisms underlying moral conviction, their relationship with metacognition, and how moral conviction is integrated into the valuation and decision-making process remain unclear. This study investigated these neurocognitive processes during decision-making on sociopolitical issues varying in moral conviction. Participants (N = 44) underwent fMRI scanning while deciding, on each trial, which of two groups of political protesters they supported more. As predicted, stronger moral conviction was associated with faster decision times. Hemodynamic responses in the anterior insula (aINS), anterior cingulate cortex (ACC), and lateral prefrontal cortex (lPFC) were elevated during decisions with higher moral conviction, supporting the emotional and cognitive dimensions of moral conviction. Functional connectivity between lPFC and vmPFC was greater on trials higher in moral conviction, elucidating mechanisms through which moral conviction is incorporated into valuation. Average support for the two displayed groups of protesters was positively associated with brain activity in regions involved in valuation, particularly vmPFC and amygdala. Metacognitive sensitivity, the ability to discriminate one's correct from incorrect judgments, measured in a perceptual task, negatively correlated with parametric effects of moral conviction in the brain, providing new evidence that metacognition modulates responses to morally convicted issues.

The impact of emotional feedback in learning easy and difficult tasks - an ERP study

Learning from the emotional reaction of others is crucial in our everyday lives. We assumed that additional emotional information could be especially beneficial, when a task is difficult and the limits of working memory capacity are reached. For this reason, we examined whether a potential benefit of emotional feedback during reinforcement learning is dependent on working memory load. In addition to learning performance, we analysed the neural mechanisms of reinforcement learning by examining two event-related potentials (ERPs): feedback-related negativity (FRN) and P3b. Participants were divided into two difficulty groups (with n = 21 in the difficult and n = 22 in the easy group), performing a learning task with emotional or non-emotional feedback. Task difficulty was manipulated by varying the number of stimulus-response associations. Participants' showed learning in all conditions. Emotional feedback led to increased accuracy and decreased reaction times in both groups. However, this benefit occurred earlier in the easy condition. The detection of unexpected events, as reflected in the peak-to-peak FRN, as well as working memory updating, as reflected in the P3b, were enhanced after emotional in contrast to non-emotional feedback for both groups. In contrast, task difficulty had no effect on the detection of unexpected events but led to a P3b that was more evenly distributed over the scalp, which could indicate that additional frontal resources were recruited to perform the difficult task. Our results suggest that working memory load and emotional information independently influence feedback processing without interacting.

Decision-making and performance in the Iowa Gambling Task: recent ERP findings and clinical implications

The Iowa Gambling Task (IGT) is a widely used tool for assessing decision-making in clinical populations. In each trial of the task, participants freely select from different playing card decks that vary in the magnitude and frequency of rewards and punishments. Good decks offer relatively smaller rewards on each trial yielding greater overall winnings while bad decks result in a net loss over time as high penalties negate any rewards earned. Comparing participants' rate of selecting good to bad decks can provide insight into learning in uncertain conditions across time. However, inconsistent patterns of deficits and learning within clinical and control populations are often observed in the task (eg., in depression). Thus, a clearer mechanistic understanding of the IGT is needed to fully understand the decision-making process. The goal of the current review is to synthesize the predominant empirical and theoretical literature of the IGT using event-related potentials (ERPs) derived from electroencephalogram (EEG). The review then explores how modifications of the IGT allow for event-related potentials to be captured at each stage of decision-making. Lastly, the review discusses how the modified version with ERPs can be further applied to directly assess the impact of emotion processing on decision-making, using findings from depression research as an example.

Neurophysiological characteristics of reward processing in deaf college students under different social contexts

Background

In the context of social exclusion, individuals tend to make choices that are advantageous to themselves and optimize their interests. Due to hearing impairment, deaf college students face more social exclusion in our society. However, the neural mechanisms of reward processing in deaf college students during different situations of social exclusion remain unknown.

Methods

A total of 27 deaf college students completed the monetary and social reward delay tasks while recording event-related potential (ERP) data.

Results

The behavioral hit rate was sensitive to the main effect of social context; that is, the deaf college students showed a higher hit rate in social inclusion than in social exclusion. The amplitude of Cue P3 elicited by reward cues was found to be higher in social exclusion than in social inclusion, particularly when the amplitudes of monetary cues were higher than those of social cues. In the reward feedback outcome phase, small magnitude induced a greater feedback-evoked P3 than large magnitude. Additionally, they exhibited a large feedback-related negativity amplitude for large-magnitude (but not for small-magnitude) monetary reward cues.

Conclusion

Deaf college students were more sensitive to reward cues in social exclusion than in social inclusion, especially to monetary cues, and more concerned with attaining greater monetary gains.

Test-retest reliability of decisions under risk with outcome evaluation: evidence from behavioral and event-related potentials (ERPs) measures in 2 monetary gambling tasks

The balance between potential gains and losses under risk, the stability of risk propensity, the associated reward processing, and the prediction of subsequent risk behaviors over time have become increasingly important topics in recent years. In this study, we asked participants to carry out 2 risk tasks with outcome evaluation-the monetary gambling task and mixed lottery task twice, with simultaneous recording of behavioral and electroencephalography data. Regarding risk behavior, we observed both individual-specific risk attitudes and outcome-contingent risky inclination following a loss outcome, which remained stable across sessions. In terms of event-related potential (ERP) results, low outcomes, compared to high outcomes, induced a larger feedback-related negativity, which was modulated by the magnitude of the outcome. Similarly, high outcomes evoked a larger deflection of the P300 compared to low outcomes, with P300 amplitude also being sensitive to outcome magnitude. Intraclass correlation coefficient analyses indicated that both the feedback-related negativity and P300 exhibited modest to good test-retest reliability across both tasks. Regarding choice prediction, we found that neural responses-especially those following a loss outcome-predicted subsequent risk-taking behavior at the single-trial level for both tasks. Therefore, this study extends our understanding of the reliability of risky preferences in gain-loss trade-offs.

Revisiting the electrophysiological correlates of valence and expectancy in reward processing - A multi-lab replication

Two event-related brain potential (ERP) components, the frontocentral feedback-related negativity (FRN) and the posterior P300, are key in feedback processing. The FRN typically exhibits greater amplitude in response to negative and unexpected outcomes, whereas the P300 is generally more pronounced for positive outcomes. In an influential ERP study, Hajcak et al., (2005) manipulated outcome valence and expectancy in a guessing task. They found the FRN was larger for negative outcomes regardless of expectancy, and the P300 larger for unexpected outcomes regardless of valence. These findings challenged the dominant Reinforcement Learning Theory of the ERN. We aimed to replicate these results within the #EEGManyLabs project (Pavlov et al., 2021) across thirteen labs. Our replication, including robustness tests, a PCA and Bayesian models, found that both FRN and P300 were significantly modulated by outcome valence and expectancy: FRN amplitudes (no-reward - reward) were largest for unexpected outcomes, and P300 amplitudes were largest for reward outcomes. These results were consistent across different methods and analyses. Although our findings only partially replicate the original study, they underscore the complexity of feedback processing and demonstrate how aspects of Reinforcement Learning Theory may apply to the P300 component, reinforcing the need for rigorous ERP research methodologies.

Attachment Security Priming Reduces Risk-Taking and Emotional Responses to Loss

We examined the effects of attachment security priming on economic risky decisions and their neural underpinnings. Participants were exposed to either attachment security primes (N = 28) or control primes (N = 29) and then completed a gambling task while connected to an electroencephalogram system. We anticipated that attachment security priming would affect risky decision-making at both the behavioral and neural levels. Feedback-related negativity (FRN) and P3 components were analyzed. At the behavioral level, participants in the attachment security priming group selected less risky choices than those in the control group. At the neural level, participants exposed to attachment security primes exhibited attenuated FRN but no significant difference in P3 amplitude. The regression analysis showed that small P3 amplitude predicted large risk-taking tendencies in the control priming group, whereas P3 amplitude did not significantly predict risk-taking tendencies in the attachment security priming group. These findings suggest how boosted attachment security affects economic risky decisions: It lowers people's affective reactions to undesirable outcomes and buffers people's underestimation of the outcome salience. Specifically, attachment security seems to attenuate risk-taking by preventing people from down playing the significance of outcomes. Our findings extend existing knowledge by demonstrating attachment security priming ability to reduce risk-taking tendencies beyond naturalistic to economic decisions.

Theta-Gamma Decoupling - A neurophysiological marker of impaired reward processing in Parkinson's disease

Individuals with Parkinson's disease (PD) exhibit altered reward processing, reflected by a decreased amplitude of an event-related potential (ERP) marker called reward positivity (RewP). Most studies have used RewP to investigate reward behavior due to the high temporal resolution of EEG and its high sensitivity. However, traditional single-electrode ERP analyses often overlook the intricate dynamics of non-phase-locked oscillatory activity and the complex interactions within these neural oscillatory patterns. Studying oscillatory activity is crucial as it provides mechanistic insights into the functional, spatial, and temporal aspects of neuronal processing. To address this gap, we employed a data-driven approach to identify EEG-based markers associated with PD reward processing deficits. Using an openly available 64-channel EEG dataset of 28 age- and sex-matched PD and control participants during a reinforcement learning task, we conducted a comprehensive secondary analysis. First, we employed a cluster-based permutation method to extract ERP markers, finding a consistent decrease in reward positivity in PD, regardless of medication status. Additionally, through region of interest (ROI) analysis on time-frequency data, we identified specific oscillatory patterns during reward processing. PD patients exhibited attenuated theta power and increased gamma power compared to healthy controls (HC). Notably, within the PD group, those off medication showed anterior localization of high gamma power, while those on medication displayed higher posterior gamma power. Building upon these findings, we explored phase-amplitude coupling between theta phase and gamma amplitude measured by the modulation index. We observed a trend of decreased theta-gamma coupling in PD patients, with statistically significant differences between on and off medication conditions. These results highlight the potential role of theta-gamma coupling as a neuromodulatory target for improving goal-oriented behavior in PD. Our correlation analyses suggest that high gamma power is linked to longer disease duration, while reduced reward positivity and low theta-gamma coupling may serve as markers of the dopaminergic impact on reward processing. Thus, our study unveils the intricate time-frequency dynamics underlying reward processing deficits in PD, emphasizing the utility of a data-driven approach to elucidate neural mechanisms and to identify potential therapeutic targets.

Dissociable effects of perceived control on reward-related neural dynamics under risk and ambiguity

Perceived control plays a crucial role in risk-taking behavior, but its neural effect on reward dynamics in risky and ambiguous decision making remains unclear. Here, we addressed this issue by measuring participants' (N = 40) EEG activity while they were performing a wheel-of-fortune task. Participants either made choices themselves (a high control condition) or followed the computer's choice (a low control condition) under risky or ambiguous decision contexts. Behavioral and rating data showed a stronger control effect in the risky compared to the ambiguous decision context. In parallel, we found an effect of perceived control on choice evaluation (indexed by the cue-P3) in the risky but not ambiguous context. However, the control effect was more pronounced during feedback anticipation (indexed by the stimulus-preceding negativity) and outcome appraisal (indexed by delta oscillation) in the ambiguous context compared to the risky context. Together, our findings suggest that experiencing control alters reward dynamics in uncertain decision making, with dissociable effects between risk and ambiguity.

Facial attractiveness influenced cooperative behavior in the Stag Hunt game: Evidence from neural electrophysiology

Facial attractiveness plays a significant role in interpersonal interactions, influencing various aspects of life. This study is the first to explore, from a neurological perspective, the impact of facial attractiveness on individual cooperative behavior in the context of the Stag Hunt game. Twenty-six participants took part in a two-person Stag Hunt experimental task, while their electroencephalogram (EEG) data were recorded. Participants had to decide whether to cooperate with or to defect from a virtual partner in the game, with photos of these partners (high or low attractiveness) shown before the decision. Analysis of the behavioral data indicates that faces with high attractiveness can promote individual cooperative behavior. EEG data analysis revealed that during the facial stimulus presentation phase, low attractiveness faces elicited more negative N2 amplitudes, smaller late positive potential amplitudes, and larger alpha oscillations compared to high attractiveness faces. During the outcome feedback phase, high attractiveness faces elicited smaller feedback-related negativity (FRN) amplitudes, larger P300 amplitudes, and stronger theta oscillations than low attractiveness faces, while loss feedback elicited more negative FRN amplitudes, smaller P300 amplitudes, and larger theta oscillations than gain feedback. These findings indicate that the processing of facial attractiveness occurs early and automatically, and it also influences individuals' evaluation of behavioral outcomes.

Exercising self-control increases responsivity to hedonic and eudaimonic rewards

The reward responsivity hypothesis of self-control proposes that irrespective of self-control success, exercising self-control is aversive and engenders negative affect. To countermand this discomfort, reward-seeking behavior may be amplified after bouts of self-control, bringing individuals back to a mildly positive baseline state. Previous studies indicated that effort-an integral component of self-control-can increase reward responsivity. We sought to test and extend the reward responsivity hypothesis by asking if exercising self-control increases a neural marker of reward responsivity [Reward Positivity (RewP)] differentially for hedonic rewards or eudaimonic rewards. We instructed participants (N = 114) to complete a speeded reaction time task where they exercised self-control (incongruent Stroop trials) or not (congruent Stroop trials) and then had the opportunity to win money for themselves (hedonic rewards) or a charity (eudaimonic rewards) while electroencephalography was recorded. Consistent with the reward responsivity hypothesis, participants evinced a larger RewP after exercising self-control (vs. not exercising self-control). Participants also showed a larger RewP for hedonic over eudaimonic rewards. Self-control and reward type did not interactively modulate RewP, suggesting that self-control increases reward responsivity in a domain-general manner. The findings provide a neurophysiological mechanism for the reward responsivity hypothesis of self-control and promise to revitalize the relevant literature.

Good luck or bad luck? The influence of social comparison on risk-taking decision and the underlying neural mechanism

The present study aimed to investigate the impact of social comparison on risk-taking behaviors and the neural underpinnings within a competitive context. Participants who thought they were playing against a stranger in a gambling task were actually playing against a programmed computer. Eighty-eight college students were assigned to one of three comparison conditions (downward, upward, and parallel) by varying the probability of gain. Behavioral results showed that disadvantage led to increased risk-taking. Event-related potential data analyses showed, in the parallel comparison condition, a significantly larger Feedback-Related Negativity (FRN) was induced by the self's safe decision than the risky decision and by loss rather than gain. However, in the upward and downward comparison conditions, larger FRN emerged solely in response to the loss of risky rather than safe decisions. On the P3 component, participants in the upward comparison condition showed no significant difference in response to their gain or loss, while the other two conditions did. The highest P3 amplitude, delta/theta power, and aperiodic activity were found in the closely matched condition. Finally, in the downward comparison condition, a stronger delta/theta power was correlated with a less risky decision. Overall, the findings indicate that parity heightens emotional arousal and engages more cognitive resources.

Performance monitoring of improvisation and score-playing in a turn-taking piano duet: An EEG study using altered auditory feedback

In music ensemble performance, perception-action coupling enables the processing of auditory feedback from oneself and other players. However, improvised actions may affect this coupling differently from predetermined actions. This study used two-person EEG to examine how pianists responded to altered pitch feedback to their own or their partner's actions while they alternated scores or improvised melodies. Feedback-related negativity (FRN) response for self-action was greater in scored than improvised conditions, indicating the enhanced action encoding by playing the score. However, subsequent P3a and P3b responses for self-action were not different across score and improvisation. Further, the P3b response was greater when the two pianists exchanged similar types of melodies (i.e., both improvised or both scores) compared with different types of melodies, suggesting that later cognitive processes may be associated with the task relevance or level of jointness. The presence of the FRN and P3 complex in self-generated improvised action points to the dynamic nature of performance monitoring even without preconceived action plans. In contrast, the FRN and P3 complex in partner-generated improvised actions were subdued compared to the baseline, likely due to the unpredictable nature of the improvised actions of others. Finally, we found a tendency that higher trait empathy was associated with smaller self-action FRN, possibly implying musicians' prioritization of joint goals. Overall, our results suggest that improvisation in a musical turn-taking task may be distinct from score-playing for the earlier processes of performance monitoring, whereas later processes might involve updating a joint representation of the musical context.

Reward processing dominates the brain during feedback evaluation: Electrophysiological evidence

During reinforcement learning, people learn based on both positive and negative feedback. Researchers have revealed the reward positivity (RewP) that reflects positive feedback evaluation, however, no electrophysiological indicator has been found to explain negative feedback processing. In reinforcement learning, people would like to expect the positive feedback after a choice, which might explain why previous studies usually found neural responses for reward processing, while the negative feedback processing seems absent. However, no study has designed a task to separate positive and negative feedback processing to measure the corresponding electrophysiological responses. Thus, the present study designed gain processing-advantaged (GA) and loss processing-advantaged (LA) contexts using a modified gambling task to measure specific neural responses to gain processing and loss processing. Electroencephalography (EEG) data were processed using time-domain and time-frequency analyses. The results revealed the RewP and delta oscillation following gain feedback in the GA context, while no negativity or other components specific to loss processing was found, even in the loss condition of LA context. The current results indicate that reward processing dominates the brain during feedback evaluation, whereas loss processing can't be captured by electrophysiological signal.

Unravelling the origin of reward positivity: a human intracranial event-related brain potential study

Reward positivity (RewP) is an event-related brain potential component that emerges ∼250-350 ms after receiving reward-related feedback stimuli and is believed to be important for reinforcement learning and reward processing. Although numerous localization studies have indicated that the anterior cingulate cortex (ACC) is the neural generator of this component, other studies have identified sources outside of the ACC, fuelling a debate about its origin. Because the results of EEG and magnetoencephalography source-localization studies are severely limited by the inverse problem, we addressed this question by leveraging the high spatial and temporal resolution of intracranial EEG. We predicted that we would identify a neural generator of rthe RewP in the caudal ACC. We recorded intracranial EEG in 19 patients with refractory epilepsy who underwent invasive video-EEG monitoring at Ghent University Hospital, Belgium. Participants engaged in the virtual T-maze task, a trial-and-error task known to elicit a canonical RewP, while scalp and intracranial EEG were recorded simultaneously. The RewP was identified using a difference wave approach for both scalp and intracranial EEG. The data were aggregated across participants to create a virtual 'meta-participant' that contained all the recorded intracranial event-related brain potentials with respect to their intracranial contact locations. We used both hypothesis-driven (focused on ACC) and exploratory (whole-brain analysis) approaches to segment the brain into regions of interest. For each region of interest, we evaluated the degree to which the time course of the absolute current density (ACD) activity mirrored the time course of the RewP, and we confirmed the statistical significance of the results using permutation analysis. The grand average waveform of the scalp data revealed a RewP at 309 ms after reward feedback with a frontocentral scalp distribution, consistent with the identification of this component as the RewP. The meta-participant contained intracranial event-related brain potentials recorded from 582 intracranial contacts in total. The ACD activity of the aggregated intracranial event-related brain potentials was most similar to the RewP in the left caudal ACC, left dorsolateral prefrontal cortex, left frontomedial cortex and left white matter, with the highest score attributed to caudal ACC, as predicted. To our knowledge, this is the first study to use intracranial EEG aggregated across multiple human epilepsy patients and current source density analysis to identify the neural generator(s) of the RewP. These results provide direct evidence that the ACC is a neural generator of the RewP.

Opening the Pandora box: Neural processing of self-relevant negative social information

Curiosity is a powerful motivator of information-seeking behavior. People seek not only positive, but also aversive social information about others. However, whether people also seek unfavorable social information about themselves, as well as the neural mechanisms that may drive such seemingly counterintuitive behavior remain unclear. To address this gap, we developed a novel electroencephalography-compatible Social Incentive Delay (SID) task, which was implemented in 30 healthy young adults as they responded as fast as possible to a target to receive positive or avoid negative comments about their own or about others' Instagram photos. Reaction times were slower for negative vs positive comments' conditions, but only for participants' own photos, revealing less motivation to avoid negative rather than seek positive self-relevant social feedback. Coherently, receiving negative feedback, as opposed to avoiding it, evoked larger amplitudes in the Reward Positivity (RewP) and FB-P3 time-range, especially for participants' own photos, indicating that receiving a negative comment was more rewarding and more salient than not receiving any comment at all. Our findings challenge prior evidence suggesting that humans instinctively avoid aversive stimuli, and they shed light on the neurophysiological mechanisms that may underlie this counterintuitive behavior.

How individuals evaluate the confidence of advice from advisors with high- and low-status: A behavioural and ERP study

Although previous studies have shown that both advisors' social status and confidence level affect advisees' advice-taking behavior, it is currently unclear the mechanisms of their common actions. Here, using event-related potentials, we investigated how both advisors' social status and confidence level independently or jointly influence advice-taking behavior. Specifically, participants were asked to make choices in a dot-estimation task and then they would receive high- and low-confidence advice from advisors with high- and low-status. Behaviorally, an interaction effect between advisors' status and confidence was found, suggesting that individuals were more likely to take high-confidence (vs. low-confidence) advice whether it was from high-status or low-status advisors. However, such an effect of confidence was larger for high-status advisors rather than for low-status advisors. On the electrophysiological level, during the early stage of processing advice, an interaction effect between advisors' status and confidence was only observed on the theta power rather than the FRN component, suggesting that the larger theta power was observed for low-confidence (vs. high-confidence) advice from low-status advisors rather than high-status advisors. Besides, although the larger P3 and beta power were found for advice from high-status advisors (vs. low-status advisors) or advice with high-confidence (vs. low-confidence), no interaction effect between status and confidence was found. Taken together, our findings suggested that advisors' status and confidence might affect the multiple stages in different ways during processing advice.

The Reward Positivity Mediates the Association Between Adverse Childhood Experiences and Anhedonia in Young Adults With Drug-Naïve Major Depressive Disorder

BACKGROUND

Current clinical studies have indicated that major depressive disorder (MDD) concurrent with adverse childhood experiences (ACEs) is associated with greater anhedonia. However, little is known about whether the change in reward sensitivity among young individuals with MDD and ACEs is related to anhedonia.

METHODS

We evaluated anhedonia and ACEs in 86 patients with MDD (31 with no or 1 ACE and 55 with 2 or more ACEs) and 44 healthy control participants. Then, participants completed the Iowa Gambling Task during electroencephalography to measure the reward positivity (RewP) and its difference (ΔRewP; gains minus losses). Furthermore, we constructed a mediation model to assess whether aberrant ΔRewP mediated the relationship between ACEs and anhedonia.

RESULTS

Compared with healthy control participants and MDD patients with no or 1 ACE, MDD patients with 2 or more ACEs had the most severe symptoms of anhedonia and impaired decision making and showed significantly reduced reward sensitivity (most blunted ΔRewP). More importantly, ΔRewP mediated the relationship between ACEs and anhedonia in MDD.

CONCLUSIONS

We found that the ΔRewP partially mediated the association between ACEs and anhedonia in patients with MDD, which provides evidence for the neurobiological basis of abnormal changes in the reward system in MDD individuals with early adverse experiences.

College students with depression symptom are more sensitive to task difficulty in reinforcement learning

BACKGROUND

Depression is usually characterized by impairments in reward function, and shows altered motivation to reward in reinforcement learning. This study further explored whether task difficulty affects reinforcement learning in college students with and without depression symptom.

METHODS

The depression symptom group (20) and the no depression symptom group (26) completed a probabilistic reward learning task with low, medium, and high difficulty levels, in which task the response bias to reward and the discriminability of reward were analyzed. Additionally, electrophysiological responses to reward and loss feedback were recorded and analyzed while they performed a simple gambling task.

RESULTS

The depression symptom group showed more response bias to reward than the no depression symptom group when the task was easy and then exhibited more quickly decrease in response bias to reward as task difficulty increased. The no depression symptom group showed a decrease in response bias only in the high-difficulty condition. Further regression analyses showed that, the Feedback-related negativity (FRN) and theta oscillation could predict response bias change in the low-difficulty condition, the FRN and oscillations of theta and delta could predict response bias change in the medium and high-difficulty conditions.

LIMITATIONS

The electrophysiological responses to loss and reward were not recorded in the same task as the reinforcement learning behaviors.

CONCLUSIONS

College students with depression symptom are more sensitive to task difficulty during reinforcement learning. The FRN, and oscillations of theta and delta could predict reward leaning behavior.

Neural Mechanism of Musical Pleasure Induced by Prediction Errors: An EEG Study

BACKGROUND/OBJECTIVES

Musical pleasure is considered to be induced by prediction errors (surprise), as suggested in neuroimaging studies. However, the role of temporal changes in musical features in reward processing remains unclear. Utilizing the Information Dynamics of Music (IDyOM) model, a statistical model that calculates musical surprise based on prediction errors in melody and harmony, we investigated whether brain activities associated with musical pleasure, particularly in the θ, β, and γ bands, are induced by prediction errors, similar to those observed during monetary rewards.

METHODS

We used the IDyOM model to calculate the information content (IC) of surprise for melody and harmony in 70 musical pieces across six genres; eight pieces with varying IC values were selected. Electroencephalographic data were recorded during listening to the pieces, continuously evaluating the participants' subjective pleasure on a 1-4 scale. Time-frequency analysis of electroencephalographic data was conducted, followed by general linear model analysis to fit the power-value time course in each frequency band to the time courses of subjective pleasure and IC for melody and harmony.

RESULTS

Significant positive fits were observed in the β and γ bands in the frontal region with both subjective pleasure and IC for melody and harmony. No significant fit was observed in the θ band. Both subjective pleasure and IC are associated with increased β and γ band power in the frontal regions.

CONCLUSIONS

β and γ oscillatory activities in the frontal regions are strongly associated with musical rewards induced by prediction errors, similar to brain activity observed during monetary rewards.

Interpersonal distance affects advisors' responses to feedback on their advice: Evidence from event-related potentials

Advisors typically receive two types of feedback: whether their advice is accepted and benefits the advisee. However, the effect of interpersonal distance on advisors' feedback responses remains unexplored. Therefore, to examine this association, we used an advice-giving task in which participants acted as advisors to either friends or strangers through event-related potentials (ERP). Participants received feedback reflecting whether their advice was accepted or rejected and the advisee's outcome (gains or losses). Participants' electroencephalograms were recorded when receiving feedback. Results revealed that rejections from friends elicited stronger feedback-related negativity (FRN) than acceptances from friends. Furthermore, acceptances from friends triggered larger late positive components (LPCs) than rejections from friends. No such effects were observed when the advisee was a stranger. Moreover, a stronger FRN was observed for losses than gains when strangers accepted the advice; however, this difference was not observed when strangers rejected the advice. In addition, friends' gains elicited a larger P300 than losses, regardless of whether friends accepted the advice; however, for strangers, this P300 difference was observed only when the advice was accepted. When strangers accepted the advice, gains elicited larger LPCs than losses; however, this difference was not observed when strangers rejected the advice. These results revealed that the interpersonal distance between people affected how they responded to feedback on advice. This was demonstrated by the neural responses related to expectations, motivational significance, and emotional arousal. It also suggests that the psychological processes by which interpersonal distance influences feedback processing change over the stages.

Neurophysiological activity following gains and losses among young adults with non-suicidal self-injury: An ERP study

OBJECTIVE

Non-suicidal self-injury (NSSI) is an increasingly concerning issue that is linked to a range of mental health problems. However, little is known about the potential neurophysiological mechanisms underlying risk decision-making in Major depressive disorder (MDD) patients with NSSI-the present study aimed to fill this important literature gap.

METHODS

A total of 81 MDD patients (with NSSI: n = 40, without NSSI: n = 41) and 44 matched healthy controls (HC) underwent a modified version of the Iowa Gambling Task (IGT) while an electroencephalogram was recorded. Feedback-related negativity (FRN) and P300 were examined during the feedback stage of the risky decision-making process.

RESULTS

Behavioural findings revealed that individuals diagnosed with MDD displayed a greater tendency to make risky decisions compared to the control group. Furthermore, MDD patients with NSSI demonstrated a significantly more negative ΔFN (i.e., the difference in neural response to losses compared to gains) than those without NSSI. Further, NSSI patients showed a larger difference ΔFN (loss minus gain), which was associated with enhanced impulsivity.

CONCLUSIONS

Collectively, the findings suggest that there is an altered processing of risky decision-making in the electrophysiology of patients with MDD who engage in NSSI. The ΔFN may serve as a psychophysiological marker indicating risk for NSSI.

The modulation of reward expectancy on the processing of near-miss outcomes: An ERP study

A near-miss is a situation in which a gambler almost wins but falls short by a small margin, which motivates gambling by making it feel like success is within reach. Existing research has extensively investigated the influence of contextual information on near-miss outcome processing; however, the impact of reward expectancy has received limited attention thus far. To address this gap, we utilized the wheel of fortune task and event-related potential technique (ERP) to quantify the electrophysiological responses associated with gambling outcomes at different levels of reward expectancy. Behaviorally, near-miss outcomes elicited a greater occurrence of counterfactual thoughts, feelings of regret, and heightened anticipation of rewards for subsequent trials compared to full-miss outcomes. ERP findings indicated that in contrast to full-miss outcomes, near-miss outcomes diminished feedback-related negativities (FRNs) and amplified P300s when reward expectancy was low, but amplified FRNs and diminished P300s when reward expectancy was high. These findings provide valuable insights into the neural mechanisms underlying the processing of outcome proximity and reward expectancy.

Event-related potentials of social comparisons in depression and social anxiety

Social comparison is central in human life and can be especially challenging in depression and social anxiety. We assessed event-related potentials and emotions using a social comparison task in which participants received feedback on both their own and a co-player's performance, in participants with depression and/or social anxiety (n = 63) and healthy controls (n = 72). Participants reported more negative emotions for downward (being better than the co-player [participant correct, co-player wrong]) and upward (being worse than the co-player [participant wrong, co-player correct]) comparisons versus even outcomes, with these effects being stronger in depression and social anxiety. At the Medial Frontal Negativity, both controls and depressed participants showed a more negative amplitude for upward comparison versus both the participant and co-player performing wrong. Socially anxious subjects showed the opposite effect, possibly due to greater expectations about being worse than others. The P300 decreased for downward and upward comparisons compared to even outcomes, which may relate to the higher levels of conflict of social inequality. Depressed and socially anxious subjects showed a blunted P300 increase over time in response to the task outcomes, suggesting deficits in allocating resources for the attention of incoming social information. The LPP showed increased amplitude for downward and upward comparison versus the even outcomes and no group effect. Emotional findings suggest that social comparisons are more difficult for depressed and socially anxious individuals. Event-related potentials findings may shed light on the neural substrates of these difficulties.

The ERP Components of Reward Processing Modulated by Status-Related Social Comparison

Background

Although social status is closely related to income distribution, few studies have focused on social comparisons caused by income distribution based on social status.

Purpose

The neural indices of status-related social comparisons were investigated by modifying the classical social comparison task with the incorporation of event-related potentials (ERPs).

Methods

The study employed a total of 29 subjects (15 females), the status scores of whom were initially obtained through the utilization of classical measurements of objective (7 items) and subjective (2 items) socioeconomic status. Subsequently, the subjects were required to complete a dot-estimation task. To induce status-related and response-related (upward, equal, and downward) social comparisons, subjects were informed that rewards were distributed based on whether their status score or their response was superior to that of a selected competitor.

Results

The behavioral results demonstrated that status-related social comparisons were perceived as more unfair than response-related social comparisons. The ERP results indicated that the cue-P3 amplitude was lower under status-related cues than response-related cues. Additionally, the amplitude of feedback-related negativity was larger under status-related equal comparisons than response-related equal comparisons. Furthermore, the P3 amplitude was larger under status-related upward comparisons relative to response-related upward comparisons.

Conclusion

The findings indicated that status-related comparisons may contribute to the development of unfair consideration (enhanced FRN) and a reduction in task motivations (lowered cue-P3). Additionally, the status-related upward comparison may serve as a significant factor in the onset of relative deprivation (enhanced P3). It would therefore be beneficial to gain further insight into the neural basis of social comparisons.

Executive control can query hidden human memories

When we try to retrieve a representation from visual long-term memory there is a chance that we will fail to recall seeing it even though the memory is stored in our brain. Here we show that although mechanisms of explicit memory retrieval are sometimes unable to retrieve stored memories, that mechanisms of executive control can quickly query memory and determine if a representation is stored therein. Our findings suggest that the representations stored in human memory that cannot be accessed explicitly at that moment are nonetheless directly accessible by the brain's higher level control mechanisms.

A U-shaped relationship between chronic academic stress and the dynamics of reward processing

Despite the potential link between stress-induced reward dysfunctions and the development of mental problems, limited human research has investigated the specific impacts of chronic stress on the dynamics of reward processing. Here we aimed to investigate the relationship between chronic academic stress and the dynamics of reward processing (i.e., reward anticipation and reward consumption) using event-related potential (ERP) technology. Ninety healthy undergraduates who were preparing for the National Postgraduate Entrance Examination (NPEE) participated in the study and completed a two-door reward task, their chronic stress levels were assessed via the Perceived Stress Scale (PSS). The results showed that a lower magnitude of reward elicited more negative amplitudes of cue-N2 during the anticipatory phase, and reward omission elicited more negative amplitudes of FRN compared to reward delivery especially in high reward conditions during the consummatory phase. More importantly, the PSS score exhibited a U-shaped relationship with cue-N2 amplitudes regardless of reward magnitude during the anticipatory phase; and FRN amplitudes toward reward omission in high reward condition during the consummatory phase. These findings suggest that individuals exposed to either low or high levels of chronic stress, as opposed to moderate stress levels, exhibited a heightened reward anticipation, and an augmented violation of expectations or affective response when faced with relatively more negative outcomes.

Receivers' responses are integrated into costly third-party punishment in a way that interacts with the unfairness of allocations

Costly third-party punishment (TPP) is an effective way to enforce fairness norms and promote cooperation. Recent studies have shown that the third party considers not only the proposer's suggested allocation but also the receiver's response to the allocation, which was typically ignored in traditional TPP studies when making punishment decisions. However, it remains unclear whether and how the varying unfair allocations and receivers' responses are integrated into third-party punishment. The current study addressed these issues at behavioral and electrophysiological levels by employing a modified third-party punishment task involving proposers' highly or moderately unfair allocations and the receivers' acceptance or rejection responses. At the behavioral level, participants punished proposers more often when receivers rejected relative to accepted unfair allocations. This effect was further modulated by the unfairness degree of allocations, indicated by a more pronounced rejection-sensitive effect when participants observed the moderately unfair offers. Electrophysiologically, when the receiver rejected the moderately unfair allocations, a stronger late-stage component P300/LPP, which was considered to be involved in allocations of attention resources, was found. Meanwhile, separated from the P300/LPP, the P200 associated with early attention capture demonstrated a rejection-sensitive effect. Together, in the costly TPP studies, the receiver is typically designated as passive and silent, and her/his responses to unfairness are conventionally ignored. However, our results indicate that except for the proposer's distribution behavior, the receiver's response does have an impact on third-party punishment in a way that interacts with the unfairness of allocations.

The influence of reward and loss outcomes after free- and forced-tasks on voluntary task choice

In four experiments, we investigated the impact of outcomes and processing mode (free versus forced) on subsequent voluntary task-switching behavior. Participants freely chose between two tasks or were forced to perform one, and the feedback they received randomly varied after correct performance (reward or no-reward; loss or no-loss). In general, we reasoned that the most recently applied task goal is usually the most valued one, leading people to prefer task repetitions over switches. However, the task values might be additionally biased by previous outcomes and the previous processing mode. Indeed, negatively reinforcing tasks with no-reward or losses generally resulted in more subsequent switches. Additionally, participants demonstrated a stronger attachment to free- compared to forced-tasks, as indicated by more switches when the previous task was forced, suggesting that people generally value free over forced-choice task goals. Moreover, the reward manipulation had a greater influence on switching behavior following free- compared to forced-tasks in Exp. 1 and Exp. 3, suggesting a stronger emphasis on evaluating rewarding outcomes associated with free-task choices. However, this inflationary effect on task choice seemed to be limited to reward and situations where task choice and performance more strongly overlap. Specifically, there was no evidence that switching behavior was differentially influenced after free-and forced-task as a function of losses (Exp. 2) or reward when task choice and task performance were separated (Exp. 4). Overall, the results provide new insights into how the valuation of task goals based on choice freedom and outcome feedback can influence voluntary task choices.

Neural responses to decision-making in suicide attempters with youth major depressive disorder

An improved understanding of the factors associated with suicidal attempts in youth suffering from depression is crucial for the identification and prevention of future suicide risk. However, there is limited understanding of how neural activity is modified during the process of decision-making. Our study aimed to investigate the neural responses in suicide attempters with major depressive disorder (MDD) during decision-making. Electroencephalography (EEG) was recorded from 79 individuals aged 16-25 with MDD, including 39 with past suicide attempts (SA group) and 40 without (NSA group), as well as from 40 age- and sex- matched healthy controls (HCs) during the Iowa Gambling Task (IGT). All participants completed diagnostic interviews, self-report questionnaires. Our study examined feedback processing by measuring the feedback-related negativity (FRN), ΔFN (FRN-loss minus FRN-gain), and the P300 as electrophysiological indicators of feedback evaluation. The SA group showed poorest IGT performance. SA group and NSA group, compared with HC group, exhibited specific deficits in decision-making (i.e., exhibited smaller (i.e., blunted) ΔFN). Post hoc analysis found that the SA group was the least sensitive to gains and the most sensitive to losses. In addition, we also found that the larger the value of ΔFN, the better the decision-making ability and the lower the impulsivity. Our study highlights the link between suicide attempts and impaired decision-making in individuals with major depressive disorder. These findings constitute an important step in gaining a better understanding of the specific reward-related abnormalities that could contribute to the young MDD patients with suicide attempts.

The impact of stress on the risk decision-making process

The effect of stress on risk-taking or risk-averse behavior in decision-making has been inconclusive in previous research, with few studies revealing the underlying neural mechanisms. This study employed event-related potentials technique and combined a social cold pressor assessment test with a mental arithmetic task to induce stress responses, aiming to investigate the influence of exogenous stress on the risk decision-making process. Stress induction results indicated that, in addition to raising heart rate and blood pressure, stress responses were accompanied by enhanced negative emotions, diminished positive emotions, and alterations in neural activity. The outcomes of risk decision-making showed that stress did not significantly affect risk preference or time of choice but did reduce the feedback-related negativity/reward positivity, with a particularly significant effect observed for large outcomes. Stress also altered the amplitude of the P3 component, with stress decreasing the P3 value for winning outcomes relative to losing outcomes. The study suggests that understanding how stress affects risk preference should consider the emotional valence induced by stress. Contrary to the reward sensitivity hypothesis, stress weakened reward sensitivity. Stress led to changes in the allocation of cognitive resources for outcome evaluation: compared to negative outcomes, stress reduced cognitive resources for positive outcomes, which might be related to the enhanced negative emotions induced by stress. The study highlights the importance of focusing on the subjective emotional experience induced by stress in future research on stress and risk decision-making.

Social and non-social feedback stimuli lead to comparable levels of reward learning and reward responsiveness in an online probabilistic reward task

Social stimuli seem to be processed more easily and efficiently than non-social stimuli. The current study tested whether social feedback stimuli improve reward learning in a probabilistic reward task (PRT), in which one response option is usually rewarded more often than the other via presentation of non-social reward stimuli. In a pre-registered online study with 305 participants, 75 participants were presented with a non-social feedback stimulus (a star) and information about gains, which is typically used in published PRT studies. Three other groups (with 73-82 participants each) were presented with one of three social feedback stimuli: verbal praise, an attractive happy face, or a "thumbs up"-picture. The data were analysed based on classical signal detection theory, drift diffusion modelling, and Bayesian analyses of null effects. All PRT variants yielded the expected behavioural preference for the more frequently rewarded response. There was no processing advantage of social over non-social feedback stimuli. Bayesian analyses further supported the observation that social feedback stimuli neither increased nor decreased behavioural preferences in the PRT. The current findings suggest that the PRT is a robust experimental paradigm independent of the applied feedback stimuli. They also suggest that the occurrence of a processing advantage for social feedback stimuli is dependent on the experimental task and design.

Anticipatory and consummatory neural correlates of monetary and music rewarding stimuli

Most of the literature on the neural bases of human reward and punishment processing has used monetary gains and losses, but less is known about the neurophysiological mechanisms underlying the anticipation and consumption of other types of rewarding stimuli. In the present study, EEG was recorded from 19 participants who completed a modified version of the Monetary Incentive Delay (MID) task. During the task, cues providing information about potential future outcomes were presented to the participants. Then, they had to respond rapidly to a target stimulus to win money or listening to pleasant music, or to avoid losing money or listening to unpleasant music. Results revealed similar responses for monetary and music cues, with increased activity for cues indicating potential gains compared to losses. However, differences emerged in the outcome phase between money and music. Monetary outcomes showed an interaction between the type of the cue and the outcome in the Feedback Related Negativity and Fb-P3 ERPs and increased theta activity increased for negative feedbacks. In contrast, music outcomes showed significant interactions in the Fb-P3 and theta activities. These findings suggest similar neurophysiological mechanisms in processing cues for potential positive or negative outcomes in these two types of stimuli.

Reward positivity affects temporal interval production in a continuous timing task

The neural circuits of reward processing and interval timing (including the perception and production of temporal intervals) are functionally intertwined, suggesting that it might be possible for momentary reward processing to influence subsequent timing behavior. Previous animal and human studies have mainly focused on the effect of reward on interval perception, whereas its impact on interval production is less clear. In this study, we examined whether feedback, as an example of performance-contingent reward, biases interval production. We recorded EEG from 20 participants while they engaged in a continuous drumming task with different realistic tempos (1728 trials per participant). Participants received color-coded feedback after each beat about whether they were correct (on time) or incorrect (early or late). Regression-based EEG analysis was used to unmix the rapid occurrence of a feedback response called the reward positivity (RewP), which is traditionally observed in more slow-paced tasks. Using linear mixed modeling, we found that RewP amplitude predicted timing behavior for the upcoming beat. This performance-biasing effect of the RewP was interpreted as reflecting the impact of fluctuations in reward-related anterior cingulate cortex activity on timing, and the necessity of continuous paradigms to make such observations was highlighted.

Exploring neural correlates of social dominance: Insights from behavioral, resting- state EEG, and ERP indices

Numerous studies have explored the concept of social dominance and its implications for leadership within the behavioral and cognitive sciences in recent years. The current study aims to address the gap regarding the neural correlates of social dominance by investigating the associations between psychological measures of social dominance and neural features among a sample of leaders. Thirty healthy male volunteers engaged in a monetary gambling task while their resting-state and task-based electroencephalography data were recorded. The results revealed a positive association between social dominance and resting-state beta oscillations in central electrodes. Furthermore, a negative association was observed between social dominance and task-based reaction time as well as the amplitude of the feedback-related negativity component of the event-related potentials during the gain, but not the loss condition. These findings suggest that social dominance is associated with enhanced reward processing which has implications for social and interpersonal interactions.

High- and low-social-anxiety individuals process the outcomes of ability comparisons differently: an event-related potential study

Individuals engage in upward or downward comparisons with superiors or inferiors, respectively. Social comparison is associated with social anxiety. Utilizing event-related potentials, we investigated how individuals with high social anxiety (HSA) and low social anxiety (LSA) evaluate self- versus other-outcomes in upward and downward comparison contexts. We found significant valence effects of self- or other-outcomes on feedback-related negativity (FRN) and P300 for both groups, with loss inducing larger FRN and smaller P300 than gain. In the early stage, the valence effect of other-outcomes was significant when LSA participants gained money, but not when they lost money, revealing a social comparison effect on FRN. Conversely, this valence effect was significant whether HSA participants gained or lost money. At the late stage, the valence effect of other-outcomes was significant when HSA or LSA participants gained money but not when they lost, revealing social comparison effects on the P300. Notably, only the social comparison effect in the LSA group was further moderated by comparison direction. These findings suggest that LSA participants engaged in social comparison throughout all evaluation stages, whereas HSA participants started at the late stage. Moreover, LSA participants were more sensitive to different comparison directions in the late stage.

Decomposing loss aversion from a single neural signal

People often display stronger aversion to losses than appetite for equivalent gains, a widespread phenomenon known as loss aversion. The prevailing theory attributes loss aversion to a valuation bias that amplifies losses relative to gains. An alternative account attributes loss aversion to a response bias that avoids choices that might result in loss. By modeling the temporal dynamics of scalp electrical activity during decisions to accept or reject gambles within a sequential sampling framework, we decomposed valuation bias and response bias from a single event-related neural signal, the P3. Specifically, we found valuation bias manifested as larger sensitivity of P3 to losses than gains, which was localizable to reward-related brain regions. By contrast, response bias manifested as larger P3 preceding gamble acceptance than rejection and was localizable to motor cortex. Our study reveals the dissociable neural biomarkers of response bias and valuation bias underpinning loss-averse decisions.

The impact of facial attractiveness and alleged personality traits on fairness decisions in the ultimatum game: Evidence from ERPs

In the mind of the beholder the personality and facial attractiveness of others are interrelated. However, how these specific properties are processed in the neurocognitive system and interact with each other while economic decisions are made is not well understood. Here, we combined the ultimatum game with EEG technology, to investigate how alleged personality traits and the perceived facial attractiveness of proposers of fair and unfair offers influence their acceptance by the responders. As expected, acceptance rate was higher for fair than unfair allocations. Overall, responders were more likely to accept proposals from individuals with higher facial attractiveness and with more positive personality traits. In ERPs, words denoting negative personality traits elicited larger P2 components than positive trait words, and more attractive faces elicited larger LPC amplitudes. Replicating previous findings, FRN amplitudes were larger to unfair than to fair allocations. This effect was diminished if the proposer's faces were attractive or associated with positive personality traits. Hence, facial attractiveness and the valence of personality traits seem to be evaluated independently and at different time points. Subsequent decision making about unfair offers is similarly influenced by high attractiveness and positive personality of the proposer, diminishing the negative response normally elicited by "unfair" proposals, possibly due a "reward" effect. In the ERPs to the proposals the effect of positive personality and attractiveness were seen in the FRN and P300 components but for positive personality traits the effect even preceded the FRN effect. Altogether, the present results indicate that both high facial attractiveness and alleged positive personality mitigate the effects of unfair proposals, with temporally overlapping but independent neurocognitive correlates.

Willingness valued more than ability in partner choice: Insights into behavioral and ERP data

In human cooperation, people prefer to choose partners with high willingness and ability-while both are valued by partners, individuals often prioritize willingness. Two event-related potential (ERP) experiments were conducted to discern the neural processes underpinning this preference. In the first experiment, participants made a choice between two potential partners and received feedback on the selected partner's willingness to cooperate. This was followed by feedback on the partner's task performance (ability) or a gambling outcome. In contrast, the second experiment first provided feedback on ability, then presented feedback on willingness or a gambling outcome. This study revealed that a potential partner's willingness trait significantly influences individuals' emotional evaluations and monetary allocations than the ability trait. Electrophysiological data indicated that low-willingness feedback elicited a diminished feedback-related negative (FRN) and an amplified P3 compared to high-willingness feedback. In contrast, no such difference was discernible between high- and low-ability feedback. Moreover, the P3 difference from high versus low willingness was considerably more pronounced than that from gambling outcomes, whereas the difference wave between high and low ability paralleled gambling outcomes. These findings bolster the novel finding that partner willingness may provide more substantial social rewards than ability. Furthermore, this study provides the first ERP evidence of willingness and ability trait perceptions in partner choice decisions.