Face-induced expectancies influence neural mechanisms of performance monitoring

Modulatory effects of positive mood and approach motivation on reward processing: Two sides of the same coin?

In a previous study (Paul & Pourtois, 2017), we found that positive mood substantially influenced the neural processing of reward, mostly by altering expectations and creating an optimistic bias. Under positive mood, the Reward Positivity (RewP) component and fronto-medial theta activity (FMθ) in response to monetary feedback were both changed compared with neutral mood. Nevertheless, whether positive valence per se or motivational intensity drove these neurophysiological effects remained unclear. To address this question, we combined a mindset manipulation with an imagery procedure to create and maintain three different affective states using a between-subjects design: a neutral mood, and positive mood with either high or low motivational intensity. After mood induction, 161 participants performed a simple gambling task while 64-channel EEG was recorded. FMθ activity results showed that irrespective of motivational intensity, positive compared with neutral mood altered reward expectancy. By comparison, RewP was not affected by positive mood nor motivational intensity. These results suggest that positive mood, rather than motivational intensity, is likely driving the change in reward expectation during gambling, which could reflect the presence of an optimistic bias. Moreover, at the methodological level, they confirm that the RewP ERP component and FMθ activity can capture dissociable effects during reward processing.

The reward positivity reflects the integrated value of temporally threefold-layered decision outcomes

In reinforcement learning, adaptive behavior depends on the ability to predict future outcomes based on previous decisions. The Reward Positivity (RewP) is thought to encode reward prediction errors in the anterior midcingulate cortex (aMCC) whenever these predictions are violated. Although the RewP has been extensively studied in the context of simple binary (win vs. loss) reward processing, recent studies suggest that the RewP scales complex feedback in a fine graded fashion. The aim of this study was to replicate and extend previous findings that the RewP reflects the integrated sum of instantaneous and delayed consequences of a singular outcome by increasing the feedback information content by a third temporal dimension. We used a complex reinforcement-learning task where each option was associated with an immediate, intermediate and delayed monetary outcome and analyzed the RewP in the time domain as well as fronto-medial theta power in the time-frequency domain. To test if the RewP sensitivity to the three outcome dimensions reflect stable trait-like individual differences in reward processing, a retesting session took place 3 months later. The results confirm that the RewP reflects the integrated value of complex temporally extended consequences in a stable manner, albeit there was no relation to behavioral choice. Our findings indicate that the medial frontal cortex receives fine graded information about complex action outcomes that, however, may not necessarily translate to cognitive or behavioral control processes.

Aiming at ecological validity-Midfrontal theta oscillations in a toy gun shooting task

Laboratory electroencephalography (EEG) studies have already provided important insights into the neuronal mechanisms of performance monitoring. However, to our knowledge no study so far has examined neuronal correlates of performance monitoring using an ecologically valid task outside a typical laboratory setting. Therefore, we examined midfrontal theta and the feedback-related negativity (FRN) using mobile EEG in a physical shooting task within an ecologically valid environment with highly dynamical visual feedback. Participants shot a target using a toy gun while moving and looking around freely. Shots that missed the target evoked stronger midfrontal theta activity than hits and this response was rather phase-unlocked. There was no difference between misses and hits in the FRN. The results raise the question whether the absence of certain ERP components like the FRN could be due to methodological reasons or to the fact that partially different neuronal processes may be activated in the laboratory as compared to more ecologically valid tasks. Overall, our results indicate that crucial neurocognitive processes of performance monitoring can be assessed in highly dynamic and ecologically valid settings by mobile EEG.

Converging electrophysiological evidence for a processing advantage of social over nonsocial feedback

We recently demonstrated a processing advantage of social versus nonsocial feedback stimuli in a western sample by assessing phase-locked neural responses. The current study extended our previous findings to another cultural sample (Chinese) to further test whether non-phase-locked neural oscillations also exhibit the social feedback processing advantage. Fifty-three Chinese volunteers performed a time estimation task with social and nonsocial feedback stimuli (matched for complexity) while electroencephalogram was recorded. Almost entirely replicating our previous results, feedback ERPs showed a processing advantage for social compared with nonsocial stimuli. Importantly, non-phase-locked oscillations also revealed this pattern. Frontal midline theta (FMΘ) oscillations differentiated between negative and positive feedback to a larger extent in response to social compared with nonsocial feedback. The current findings imply a rather universal effect of social stimulus characteristics during feedback processing and further corroborate the notion of social content as a distinct stimulus category.

Making mistakes in public: Being observed magnifies physiological responses to errors

As social beings, humans often find themselves in situations in which they are required to act against the backdrop of public observation. In these situations, the presence of observers may influence how we evaluate feedback and learn from it. The neural basis of such observer-induced behavioral changes is not well understood at present. In the current study, we used event-related potentials (ERPs) and event-related spectral perturbations (ERSPs) combined with a gambling task to examine how the presence of others modulates the neural representations of errors and losses. In the alone condition, participants finished the gambling task alone while in the observed condition, they were observed by two others. Results revealed that the observer effect particularly altered the feedback-related negativity (FRN) and the late positive potential (LPP). The difference in FRN amplitude between error and correct feedback was enlarged when participants were being observed. The LPP also showed a marginally enhanced amplitude difference between error and correct feedback in the observed condition. We also found that theta power was enhanced in the observed condition. Taken together, our findings suggest that neural representations of errors were influenced by the presence of others.

Mood congruent tuning of reward expectation in positive mood: evidence from FRN and theta modulations

Positive mood broadens attention and builds additional mental resources. However, its effect on performance monitoring and reward prediction errors remain unclear. To examine this issue, we used a standard mood induction procedure (based on guided imagery) and asked 45 participants to complete a gambling task suited to study reward prediction errors by means of the feedback-related negativity (FRN) and mid-frontal theta band power. Results showed a larger FRN for negative feedback as well as a lack of reward expectation modulation for positive feedback at the theta level with positive mood, relative to a neutral mood condition. A control analysis showed that this latter result could not be explained by the mere superposition of the event-related brain potential component on the theta oscillations. Moreover, these neurophysiological effects were evidenced in the absence of impairments at the behavioral level or increase in autonomic arousal with positive mood, suggesting that this mood state reliably altered brain mechanisms of reward prediction errors during performance monitoring. We interpret these new results as reflecting a genuine mood congruency effect, whereby reward is anticipated as the default outcome with positive mood and therefore processed as unsurprising (even when it is unlikely), while negative feedback is perceived as unexpected.

Electrophysiological Correlates of Cue-Related Processing in a Gambling Task: Early Outcome Evaluation or Outcome Expectation?

Several recent studies have suggested that cues that predict outcomes elicit a feedback-related-like negativity (FRN-like negativity) reflecting initial appraisals of whether desired outcomes are probable. Some other studies, however, have found that the cues that predict outcomes elicited event-related potentials (ERPs) that reflect the expectation to outcomes (e.g., outcome expectations). Given these mixed findings, this study aimed to examine whether the brain activity elicited by predictive cues in a gambling task reflected the initial evaluations of the outcomes, the outcome expectations, or both. We used a gambling task in which the participants were told to guess which of two doors hid a reward. At the beginning of each trial, a cue was presented to inform the participants of how many doors hid a reward. We found that these predictive cues elicited a FRN-like negativity at the frontal sites within around 200–300 ms. However, this negativity did not significantly differ between the cues that fully predicted gains and the cues that fully predicted losses. Furthermore, predictive cues elicited an expectation-related slow wave, and cues that predicted gains with a 50% probability elicited a larger expectation-related slow wave than cues that fully predicted gains or losses. Our results suggest that cues predicting outcomes reflect outcome expectations rather than initial evaluations of the forthcoming outcomes.

Deficits in Response Inhibition in Patients with Attention-Deficit/Hyperactivity Disorder: The Impaired Self-Protection System Hypothesis

Problems in inhibitory control are regarded in Psychology as a key problem associated with attention-deficit/hyperactivity disorder (ADHD). They, however, might not be primary deficits, but instead a consequence of inattention. At least two components have been identified and dissociated in studies in regards to inhibitory control: interference suppression, responsible for controlling interference by resisting irrelevant or misleading information, and response inhibition, referring to withholding a response or overriding an ongoing behavior. Poor error awareness and self-monitoring undermine an individual's ability to inhibit inadequate responses and change course of action. In non-social contexts, an individual depends on his own cognition to regulate his mistakes. In social contexts, however, there are many social cues that should help that individual to perceive his mistakes and inhibit inadequate responses. The processes involved in perceiving and interpreting those social cues are arguably part of a self-protection system (SPS). Individuals with ADHD not only present impulsive behaviors in social contexts, but also have difficulty perceiving their inadequate responses and overriding ongoing actions toward more appropriate ones. In this paper, we discuss that those difficulties are arguably a consequence of an impaired SPS, due to visual attention deficits and subsequent failure in perceiving and recognizing accurately negative emotions in facial expressions, especially anger. We discuss evidence that children with ADHD exhibit problems in a series of components involved in the activation of that system and advocate that the inability to identify the anger expressed by others, and thus, not experiencing the fear response that should follow, is, ultimately, what prevents them from inhibiting the ongoing inappropriate behavior, since a potential threat is not registered. Getting involved in high-risk situations, such as reckless driving, could also be a consequence of not registering a threat and thus, not experiencing fear.

The Feedback-related Negativity Reflects the Combination of Instantaneous and Long-term Values of Decision Outcomes

Hundreds of ERP studies have reported a midfrontal negative-going amplitude shift following negative compared with positive action outcomes. This feedback-related negativity (FRN) effect is typically thought to reflect an early and binary mechanism of action evaluation in the posterior midcingulate cortex. However, in prior research on the FRN effect, the instantaneous value and the long-term value of action outcomes have been perfectly confounded. That is, instantaneously positive outcomes were generally consistent with task goals, whereas instantaneously negative outcomes were inconsistent with task goals. In this study, we disentangled these two outcome aspects in two experiments. Our results reveal an interaction of instantaneous and long-term outcome values. More precisely, our findings strongly suggest that the FRN effect is mainly driven by a reward positivity, which is evoked only by outcomes that possess an instantaneously positive value and also help the organism to reach its long-term goals. These findings add to a recent literature according to which the posterior midcingulate cortex acts as a hierarchical reinforcement learning system and suggest that this system integrates instant and long-term action-outcome values. This, in turn, might be crucial for learning optimal behavioral strategies in a given setting.

Dispositional Anxiety and Frontal-Midline Theta: On the Modulatory Influence of Sex and Situational Threat

In their adaptive control hypothesis, Cavanagh and Shackman (2015) recently claimed that dispositional anxiety is correlated with frontal-midline theta (FMθ) as a generic "need for control" signal of the anterior midcingulate cortex. Here, we tested this assumption, also considering potential modulatory influences of anticipatory threat and individuals' sex. In a nonclinical sample of 168 participants (84 women), electroencephalogram was recorded while individuals performed a simple two-choice task. Half of the participants were assigned to a threat anticipation condition (anticipation of public speaking), whereas the other half was assigned to a control condition. State anxiety was monitored across the experiment. Dispositional anxiety was assessed by self-report scales, which were completed before individuals came to the laboratory. Target stimuli in the two-choice task induced a transient increase in FMθ power that was subject to an interaction of dispositional anxiety, sex, and experimental group. Only in women who anticipated public speaking did we observe a substantial positive relation between dispositional anxiety and general FMθ power. Our results indicate that the link between dispositional anxiety and FMθ is not universal but rather depends on complex interactions of individuals' sex and situational threat.