Daniela M. Pfabigan

Manipulation of feedback expectancy and valence induces negative and positive reward prediction error signals manifest in event-related brain potentials

The feedback-related negativity (FRN) has been hypothesized to be most sensitive to unexpected negative feedback. The present study investigated feedback expectancy and valence using a probabilistic gambling paradigm where subjects encountered expected or unexpected positive and negative feedback outcomes. In line with previous studies, FRN amplitude reflected a negative reward prediction error, but to a minor extent also a positive reward prediction error. Moreover, the P300 amplitude was largest after unexpected feedback, irrespective of valence. We propose to interpret the FRN in terms of a reinforcement learning signal which is detecting mismatch between internal and external representations indexed by the ACC to extract motivationally salient outcomes.

P300 amplitude variation is related to ventral striatum BOLD response during gain and loss anticipation: An EEG and fMRI experiment

The anticipation of favourable or unfavourable events is a key component in our daily life. However, the temporal dynamics of anticipation processes in relation to brain activation are still not fully understood. A modified version of the monetary incentive delay task was administered during separate functional magnetic resonance imaging (fMRI) and electroencephalogram (EEG) sessions in the same 25 participants to assess anticipatory processes with a multi-modal neuroimaging set-up. During fMRI, gain and loss anticipation were both associated with heightened activation in ventral striatum and reward-related areas. EEG revealed most pronounced P300 amplitudes for gain anticipation, whereas CNV amplitudes distinguished neutral from gain and loss anticipation. Importantly, P300, but not CNV amplitudes, were correlated to neural activation in the ventral striatum for both gain and loss anticipation. Larger P300 amplitudes indicated higher ventral striatum blood oxygen level dependent (BOLD) response. Early stimulus evaluation processes indexed by EEG seem to be positively related to higher activation levels in the ventral striatum, indexed by fMRI, which are usually associated with reward processing. The current results, however, point towards a more general motivational mechanism processing salient stimuli during anticipation.

Uncertainty during pain anticipation: The adaptive value of preparatory processes

Objectives: Anticipatory processes prepare the organism for upcoming experiences. The aim of this study was to investigate neural responses related to anticipation and processing of painful stimuli occurring with different levels of uncertainty. Experimental design: Twenty‐five participants (13 females) took part in an electroencephalography and functional magnetic resonance imaging (fMRI) experiment at separate times. A visual cue announced the occurrence of an electrical painful or nonpainful stimulus, delivered with certainty or uncertainty (50% chance), at some point during the following 15 s. Principal observations: During the first 2 s of the anticipation phase, a strong effect of uncertainty was reflected in a pronounced frontal stimulus‐preceding negativity (SPN) and increased fMRI activation in higher visual processing areas. In the last 2 s before stimulus delivery, we observed stimulus‐specific preparatory processes indicated by a centroparietal SPN and posterior insula activation that was most pronounced for the certain pain condition. Uncertain anticipation was associated with attentional control processes. During stimulation, the results revealed that unexpected painful stimuli produced the strongest activation in the affective pain processing network and a more pronounced offset‐P2. Conclusions: Our results reflect that during early anticipation uncertainty is strongly associated with affective mechanisms and seems to be a more salient event compared to certain anticipation. During the last 2 s before stimulation, attentional control mechanisms are initiated related to the increased salience of uncertainty. Furthermore, stimulus‐specific preparatory mechanisms during certain anticipation also shaped the response to stimulation, underlining the adaptive value of stimulus‐targeted preparatory activity which is less likely when facing an uncertain event. Hum Brain Mapp 36:744–755, 2015.

Empathic competencies in violent offenders

Violent offending has often been associated with a lack of empathy, but experimental investigations are rare. The present study aimed at clarifying whether violent offenders show a general empathy deficit or specific deficits regarding the separate subcomponents. To this end, we assessed three core components of empathy (emotion recognition, perspective taking, affective responsiveness) as well as skin conductance response (SCR) in a sample of 30 male violent offenders and 30 healthy male controls. Data analysis revealed reduced accuracy in violent offenders compared to healthy controls only in emotion recognition, and that a high number of violent assaults was associated with decreased accuracy in perspective taking for angry scenes. SCR data showed reduced physiological responses in the offender group specifically for fear and disgust stimuli during emotion recognition and perspective taking. In addition, higher psychopathy scores in the violent offender group were associated with reduced accuracy in affective responsiveness. This is the first study to show that mainly emotion recognition is deficient in violent offenders whereas the other components of empathy are rather unaffected. This divergent impact of violent offending on the subcomponents of empathy suggests that all three empathy components can be targeted by therapeutic interventions separately.

All about the Money – External Performance Monitoring is Affected by Monetary, but Not by Socially Conveyed Feedback Cues in More Antisocial Individuals

This study investigated the relationship between feedback processing and antisocial personality traits measured by the PSSI questionnaire (Kuhl and Kazén, 1997) in a healthy undergraduate sample. While event-related potentials [feedback related negativity (FRN), P300] were recorded, participants encountered expected and unexpected feedback during a gambling task. As recent findings suggest learning problems and deficiencies during feedback processing in clinical populations of antisocial individuals, we performed two experiments with different healthy participants in which feedback about monetary gains or losses consisted either of social–emotional (facial emotion displays) or non-social cues (numerical stimuli). Since the FRN and P300 are both sensitive to different aspects of feedback processing we hypothesized that they might help to differentiate between individuals scoring high and low on an antisocial trait measure. In line with previous evidence FRN amplitudes were enhanced after negative and after unexpected feedback stimuli. Crucially, participants scoring high on antisocial traits displayed larger FRN amplitudes than those scoring low only in response to expected and unexpected negative numerical feedback, but not in response to social–emotional feedback – irrespective of expectancy. P300 amplitudes were not modulated by antisocial traits at all, but by subjective reward probabilities. The present findings indicate that individuals scoring high on antisociality attribute higher motivational salience to monetary compared to emotional–social feedback which is reflected in FRN amplitude enhancement. Contrary to recent findings, however, no processing deficiencies concerning social–emotional feedback stimuli were apparent in those individuals. This indicates that stimulus salience is an important aspect in learning and feedback processes in individuals with antisocial traits which has potential implications for therapeutic interventions in clinical populations.

Comparing neural response to painful electrical stimulation with functional MRI at 3 and 7 T

Progressing from 3T to 7 T functional MRI enables marked improvements of human brain imaging in vivo. Although direct comparisons demonstrated advantages concerning blood oxygen level dependent (BOLD) signal response and spatial specificity, these mostly focused on single brain regions with rather simple tasks. Considering that physiological noise also increases with higher field strength, it is not entirely clear whether the advantages of 7T translate equally to the entire brain during tasks which elicit more complex neuronal processing. Therefore, we investigated the difference between 3T and 7 T in response to transcutaneous electrical painful and non-painful stimulation in 22 healthy subjects. For painful stimuli vs. baseline, stronger activations were observed at 7 T in several brain regions including the insula and supplementary motor area, but not the secondary somatosensory cortex (p<0.05 FWE-corrected). Contrasting painful vs. non-painful stimulation limited the differences between the field strengths to the periaqueductal gray (PAG, p<0.001 uncorrected) due to a similar signal increase at 7 T for both the target and specific control condition in most brain regions. This regional specificity obtained for the PAG at higher field strengths was confirmed by an additional spatial normalization strategy optimized for the brainstem. Here, robust BOLD responses were obtained in the dorsal PAG at 7 T (p<0.05 FWE-corrected), whereas at 3T activation was completely missing for the contrast against non-painful stimuli. To summarize, our findings support previously reported benefits obtained at ultra-high field strengths also for complex activation patterns elicited by painful electrical stimulation. However, this advantage depends on the region and even more on the contrast of interest. The greatest gain at 7 T was observed within the small brainstem region of the PAG, where the increased field strength offered marked improvement for the localization of activation foci with high spatial specificity.

Context-sensitivity of the feedback-related negativity for zero-value feedback outcomes.

The present study investigated whether the same visual stimulus indicating zero-value feedback (€0) elicits feedback-related negativity (FRN) variation, depending on whether the outcomes correspond with expectations or not. Thirty-one volunteers performed a monetary incentive delay (MID) task while EEG was recorded. FRN amplitudes were comparable and more negative when zero-value outcome deviated from expectations than with expected gain or loss, supporting theories emphasising the impact of unexpectedness and salience on FRN amplitudes. Surprisingly, expected zero-value outcomes elicited the most negative FRNs. However, source localisation showed that such outcomes evoked less activation in cingulate areas than unexpected zero-value outcomes. Our study illustrates the context dependency of identical zero-value feedback stimuli. Moreover, the results indicate that the incentive cues in the MID task evoke different reward prediction error signals. These prediction signals differ in FRN amplitude and neuronal sources, and have to be considered in the design and interpretation of future studies.

Affective Empathy Differs in Male Violent Offenders With High- and Low-Trait Psychopathy

This study investigated affective and cognitive empathic processes in incarcerated violent offenders with lower and higher psychopathic traits and healthy controls. Participants witnessed painful expressions of others displayed on video clips. Skin conductance responses (SCR) were recorded to assess autonomic emotional arousal, and various empathy ratings were used as measures of self-reported vicarious responses. Reduced SCRs occurred during the observation of pain in others in lower and higher psychopathic-trait participants alike, compared to controls. Despite these diminished autonomic responses indicating reduced vicarious responses, only inmates with higher psychopathic traits provided empathy ratings comparable to those of the controls. These findings indicate that violent offenders display reduced autonomic arousal in response to distress cues of others, irrespective of psychopathy. However, only higher psychopathic-trait offenders were able to provide self-report in a way that let them appear to be as empathic as controls-enabling them to know, yet not to feel, what others feel.

Feelings of helplessness increase ERN amplitudes in healthyindividuals

Experiencing feelings of helplessness has repeatedly been reported to contribute to depressive symptoms and negative affect. In turn, depression and negative affective states are associated, among others, with impairments in performance monitoring. Thus, the question arises whether performance monitoring is also affected by feelings of helplessness. To this end, after the induction of feelings of helplessness via an unsolvable reasoning task, 37 participants (20 females) performed a modified version of a Flanker task. Based on a previously validated questionnaire, 17 participants were classified as helpless and 20 as not-helpless. Behavioral measures revealed no differences between helpless and not-helpless individuals. However, we observed enhanced Error-Related Negativity (ERN) amplitude differences between erroneous and correct responses in the helpless compared to the not-helpless group. Furthermore, correlational analysis revealed that higher scores of helplessness were associated with increased ERN difference scores. No influence of feelings of helplessness on later stages of performance monitoring was observed as indicated by Error-Positivity (Pe) amplitude. The present study is the first to demonstrate that feelings of helplessness modulate the neuronal correlates of performance monitoring. Thus, even a short-lasting subjective state manipulation can lead to ERN amplitude variation, probably via modulation of mesencephalic dopamine activity.

Fearless Dominance and reduced feedback-related negativity amplitudes in a time-estimation task – Further neuroscientific evidence for dual-process models of psychopathy

Highlights • Dual-process models of psychopathy postulate two underlying dimensions.• Fearless Dominance was associated with altered feedback processing.• Feedback-related negativity amplitudes were reduced.• Self-Centered Impulsivity was unrelated to feedback processing.• These findings provide further evidence for dual-process models of psychopathy.