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How to quickly predict an individual’s behavioral choices is an important issue in the field of human behavior research. Using noninvasive electroencephalography, we aimed to identify neural markers in the prior outcome-evaluation stage and the current option-assessment stage of the chicken game that predict an individual’s behavioral choices in the subsequent decision-output stage. Hierarchical linear modeling-based brain-behavior association analyses revealed that midfrontal theta oscillation in the prior outcome-evaluation stage positively predicted subsequent aggressive choices; also, beta oscillation in the current option-assessment stage positively predicted subsequent cooperative choices. These findings provide electrophysiological evidence for the three-stage theory of decision-making and strengthen the feasibility of predicting an individual’s behavioral choices using neural oscillations.

Midfrontal theta (FMθ) in the human EEG is commonly viewed as a generic and homogeneous mechanism of cognitive control in general and conflict processing in particular. However, the role of FMθ in approach–avoidance conflicts and its cross-task relationship to simpler stimulus-response conflicts remain to be examined more closely. Therefore, we recorded EEG data while 59 healthy participants (49 female, 10 male) completed both an approach–avoidance task and a flanker task. Participants showed significant increases in FMθ power in response to conflicts in both tasks. To our knowledge, this is the first study to show a direct relationship between FMθ and approach–avoidance conflicts. Crucially, FMθ activity was task dependent and showed no cross-task correlation. To assess the possibility of multiple FMθ sources, we applied source separation [generalized eigendecomposition (GED)] to distinguish independent FMθ generators. The activity of the components showed a similar pattern and was again task specific. However, our results did not yield a clear differentiation between task-specific FMθ sources for each of the participants. Overall, our results show FMθ increases in approach–avoidance conflicts, as has been established only for more simple response conflict paradigms so far. The independence of task-specific FMθ increases suggests differential sensitivity of FMθ to different forms of behavioral conflict. SIGNIFICANCE STATEMENT FMθ is well established as an indicator for cognitive conflict in tasks involving simple stimulus–response conflicts. However, we do not yet know about its role in more complex forms of goal ambivalence, such as approach–avoidance conflicts. Thus, we implemented an approach–avoidance task and a flanker task to investigate FMθ in response to simple as well as more complex response conflicts. To our knowledge, this is the first study to show a direct relationship between FMθ and approach–avoidance conflicts. Although the transient FMθ increase is similar to that induced in a simple response conflict task, individual FMθ responsiveness to these two forms of conflict were independent of each other, suggesting intraindividual differences in the sensitivity of FMθ to different forms of behavioral conflict.

Despite a plethora of research, associations between individual differences in personality and electroencephalogram (EEG) parameters remain poorly understood due to concerns of low replicability and insufficiently powered data analyses due to relatively small effect sizes. The present article describes how a multi-laboratory team of EEG-personality researchers aims to alleviate this unsatisfactory status quo. In particular, the present article outlines the design and methodology of the project, provides a detailed overview of the resulting large-scale dataset that is available for use by future collaborators, and forms the basis for consistency and depth to the methodology of all resulting empirical articles. Through this article, we aim to inform researchers in the field of Personality Neuroscience of the freely available dataset. Furthermore, we assume that researchers will generally benefit from this detailed example of the implementation of cooperative forking paths analysis.

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.

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.

Postoperative neurologic complications have a significant effect on morbidity, mortality, and long-term disability in patients undergoing cardiac surgery. The etiology of brain injury in patients undergoing cardiac surgery is multifactorial and remains unclear. There are several perioperative causative factors for neurologic complications, including microembolization, hypoperfusion, and systemic inflammatory response syndrome. Despite technologic advances and the development of new anesthetic drugs, there remains a high rate of postoperative neurologic complications. Moreover, despite the strong evidence that volatile anesthesia exerts cardioprotective effects in patients undergoing cardiac surgery, the neuroprotective effects of volatile agents remain unclear. Several studies have reported an association of using volatile anesthetics with improvement of biochemical markers of brain injury and postoperative neurocognitive function. However, there is a need for additional studies to define the optimal anesthetic drug for protecting the brain in patients undergoing cardiac surgery.

Favourable compared to unfavourable action outcomes typically evoke a positive-going amplitude shift at frontomedial electrodes in the scalp-recorded electroencephalogram. Since prior studies on this Reward Positivity (RewP) have heavily relied on monetary outcomes, it is still debated whether the RewP is also elicited by other kinds of reward. We addressed this issue by focussing on food as another major category of daily reward. Twenty-eight healthy participants completed a decision task, in which they received images of personally liked, neutral or disliked food as outcome stimuli. Importantly, single trial outcomes were of relevance for a prolonged task goal (i.e., obtaining the liked foods and avoiding the disliked foods). The observed amplitude pattern did not correspond to the typical RewP effect observed for monetary outcomes. In particular, disliked foods evoked a similar positive-going amplitude shift as liked foods when compared to neutral foods. Exploratory analyses indicated that this pattern may result from a spatiotemporal overlap between a potential RewP response and other, emotion-related ERP components (i.e., the Early Posterior Negativity and the Late Positive Potential). We discuss our findings with regard to theoretical and methodological implications for the usage of the RewP in the study of reward processing.

In a recent study we have demonstrated that the feedback-related negativity (FRN) reflects the integrated value of instantaneous and delayed decision consequences (Osinsky et al. 2017). In the present work, we extend this research by using a novel choice task in which instant and delayed consequence values of a single decision outcome can be manipulated independently of each other in a trial-wise manner. Fifty-nine healthy participants completed this task while EEG was recorded. Twenty-two of them returned one week later for a retesting, allowing for investigating temporal stability of individual FRN indices. Our results show that the FRN mainly reflects the additively integrated value of instant and delayed outcome consequences. Individual differences in the FRN sensitivity to the two consequence dimensions were specifically predictive for consequence-driven adjustments in choice behavior and moderately stable over time. Altogether, our findings are inconsistent with the idea that the FRN reflects a simple binary distinction between favorable and unfavorable action outcomes. Rather, the FRN appears to mirror a fine-grained scaling of action outcomes, which results from stable personal reward preferences and which is used for adjusting choice behavior. Given that the FRN is generated in the anterior midcingulate cortex, our study adds to recent literature according to which this structure uses multiple information to learn complex action-outcome values.

Task motivation depends on what we did before. A recent theory differentiates between tasks that we want to do and tasks that we have to do. After a have-to task, motivation shifts towards a want-to task. We measured this shift of motivation via brain responses to monetary feedback in a risk game that was used as want-to task in our study. We tested 20 healthy participants that were about 28 years old in a within-subjects design. Participants worked on a Stroop task (have-to task) or an easier version of the Stroop task as a control condition and played a risk game afterwards (want-to task). After the Stroop task, brain responses to monetary feedback in the risk game were larger compared to the easier control task, especially for feedback indicating higher monetary rewards. We conclude that higher amplitudes of feedback-related brain responses in the risk game reflect the shift of motivation after a have-to task towards a want-to task.

We systematically compared different measures of attentional bias (i.e., reaction times, the N2pc component in the EEG, and explicit stimulus ratings) on their ability to reveal attentional engagement to threatening versus neutral facial stimuli in a Dot Probe Task and tested their relation to trait measures of general and social anxiety. We found that the N2pc component reflects a bias toward angry faces with excellent internal consistency. Similar results were obtained for explicit ratings. Reaction time (RT) differences, however, were not indicative of attentional biases and showed zero odd-even reliability. We further found that both higher (i.e., more negative) N2pc amplitudes and earlier peak latencies were associated with more severe symptoms of social anxiety even when controlling for general trait anxiety. The explicit rating biases were also specifically associated with social anxiety. Conversely, the RT bias was not related to social anxiety levels but to general trait anxiety. This highlights the importance of valid and reliable outcome measures for interventions such as attentional bias modification protocols. Mutual exclusivity of different bias operationalizations is discussed.

Several meta-analyses to date have confirmed the efficacy of attentional bias modification (ABM) in shifting reaction times away from threatening stimuli, reducing anxiety symptoms, and buffering against stressor vulnerability. The reliability of reaction time differences, however, has been found to show unacceptable psychometric properties. In this study, we tested the impact of an extensive Dot-Probe ABM procedure, consisting of close to 7000 trials, concurrently with behavioral and electrophysiological measures within a large sample of over 100 highly socially anxious participants. Results indicated that the N2pc component demonstrates superior internal consistency and more statistical power in detecting attentional biases and their modification than reaction time (RT) differences. RTs were neither indicative of an attentional bias before ABM nor of a modification over time. In contrast, the N2pc indexed both an initial attentional preference for threatening stimuli and an alteration of this relationship after training. Outcomes were not specific for attentional training away from threat but also occurred in the no-contingency control procedure, casting doubt on the theoretic underpinnings of ABM. Electrophysiological measures are an important complement to the ABM literature and should be further utilized to assess attentional biases with excellent reliability.

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.

We investigated whether greed would predict risky decision-making and recorded neural responses during a monetary gambling task using the electroencephalogram. We found that individuals high in trait-greed took higher risks to maximize monetary outcome. Furthermore, this relation was moderated by state-greed; specifically, trait-greed had a stronger impact on risky decision-making when activated by situational characteristics. On the neural level, greedy individuals showed a specific response to favorable and unfavorable outcomes. Specifically, they had a reduced feedback-related negativity-difference score to these events, indicating that they might have difficulty in learning from experience, especially from mistakes and negative feedback. It is concluded that greed may explain risky and reckless behavior in diverse settings, such as investment banking, and may account for phenomena such as stock market bubbles.

A relatively new cognitive-affective training procedure, the Attentional Bias Modification (ABM) technique, is thought to decrease biases in the allocation of attention toward negative emotional stimuli. In two studies, we tested in samples of healthy students whether a single session of ABM has an influence on early orienting of spatial attention as indexed by the N2pc. Replicating previous studies, we found an occipitotemporal N2pc (180-300 ms) contralateral to angry versus neutral facial expressions, indicating that threatening faces automatically draw attention in early stages of stimulus processing. However, this N2pc effect did not significantly change during the ABM training session. Our results therefore indicate that a single session of ABM does not affect early attentional orienting. ABM effects reported in prior research may therefore have been mediated by later cognitive-affective mechanisms.

Prior research indicates that the feedback-related negativity (FRN) reflects a good versus bad evaluation of decision outcomes, which is insensitive to the local utilitarian relation between chosen and unchosen outcomes. We tested whether this negative finding holds when the chosen outcome has an objective value of zero and therefore a comparison with the unchosen outcome is needed to identify overall choice valence. Participants completed a gambling task in which chosen and unchosen options could result in monetary wins, losses, or breaking even. Results show that the FRN does not reflect local favorableness but rather a dichotomy of gain versus no-gain for both chosen and unchosen outcomes. In contrast, P300 amplitude appears to reflect motivational salience derived from counterfactual comparisons of chosen and unchosen outcomes. Based on our and prior findings, we propose a threefold taxonomy of contextual factors and their relation to the FRN.

Previous studies have shown that ingroup/outgroup membership influences individual’s fairness considerations. However, it is not clear yet how group membership influences brain activity when a recipient evaluates the fairness of asset distribution. In this study, subjects participated as recipients in an Ultimatum Game with alleged members of both an experimentally induced ingroup and outgroup. They either received extremely unequal, moderately unequal, or equal offers from proposers while electroencephalogram was recorded. Behavioral results showed that the acceptance rates for unequal offers were higher when interacting with ingroup partners than with outgroup partners. Analyses of event related potentials revealed that proposers’ group membership modulated offer evaluation at earlier processing stages. Feedback-related negativity was more negative for extremely and moderately unequal offers compared to equal offers in the ingroup interaction whereas it did not show differential responses to different offers in the outgroup interaction. Analyses of event related oscillations revealed that the theta power (4–6 Hz) was larger for moderately unequal offers than equal offers in the ingroup interaction whereas it did not show differential responses to different offers in the outgroup interaction. Thus, early mechanisms of fairness evaluation are strongly modulated by the ingroup/outgroup membership of the interaction partner.

The feedback negativity (FN) has been repeatedly linked to expectancies about decision outcomes. Sequential outcome order is likely to influence such expectancies but has been widely disregarded. We therefore investigated whether the three-trial order of decision outcomes in a gambling task influences the FN as well as the P200 and P300. All three deflections were not only influenced by the outcome valence of the current trial but also by the outcomes of the two preceding trials. In detail, the FN and P300 to any current trial outcome were largest when the outcomes in the two preceding trials had an opposite valence. The P200 was highest in the context of two directly preceding wins, indicating that it may reflect representations of local outcome history. Our findings demonstrate that neural systems involved in decision outcome processing dynamically and continuously integrate the local outcome history for the evaluation of present outcomes.

Background Gene by environment (G×E) interaction between genetic variation in the promoter region of the serotonin transporter gene (serotonin transporter-linked polymorphic region [5-HTTLPR]) and stressful life events (SLEs) has been extensively studied in the context of depression. Recent findings suggest increased neural and endocrine stress sensitivity as a possible mechanism conveying elevated vulnerability to psychopathology. Furthermore, these G×E mediated alterations very likely reflect interrelated biological processes. Methods In the present functional magnetic resonance imaging study, amygdala reactivity to fearful stimuli was assessed in healthy male adults ( n = 44), who were previously found to differ with regard to endocrine stress reactivity as a function of 5-HTTLPR × SLEs. Furthermore, functional connectivity between the amygdala and the hypothalamus was measured as a potential mechanism linking elevated neural and endocrine responses during stressful/threatening situations. The study sample was carefully preselected regarding 5-HTTLPR genotype and SLEs. Results We report significant G×E interaction on neural response patterns and functional amygdala-hypothalamus connectivity. Specifically, homozygous carriers of the 5-HTTLPR S' allele with a history of SLEs (S'S'/high SLEs group) displayed elevated bilateral amygdala activation in response to fearful faces. Within the same sample, a comparable G×E interaction effect has previously been demonstrated regarding increased cortisol reactivity, indicating a cross-validation of heightened biological stress sensitivity. Furthermore, S'S'/high SLEs subjects were characterized by an increased functional coupling between the right amygdala and the hypothalamus, thus indicating a potential link between neural and endocrine hyperreactivity. Conclusions The present findings contribute to the ongoing debate on 5-HTTLPR × SLEs interaction and are discussed with respect to clinical implications.

The present study investigated the possibility that different aspects of performance monitoring share a common dopaminergic foundation. For this purpose we analyzed the influence of the COMT Val 158 Met polymorphism on electrophysiological markers of conflict and error monitoring, respectively. An EEG was recorded while 65 healthy subjects completed a response-conflict evoking task. In the event-related potential (ERP), both the conflict-N400 as well as the error-related negativity (ERN) were diminished in homozygous carriers of the Met allele. Moreover, the shared variance of both deflections was substantially explained by the COMT Val 158 Met genotype. These findings suggest that the relation between error- and conflict-related processes in the medial frontal cortex is mediated by a common molecular mechanism, namely the individual magnitude of phasic dopaminergic transmission.

While previous behavioural research suggests that attitudes, for example towards elderly people, may be activated automatically, this type of research does not provide information about the detailed time-course of such processing in the brain. We investigated the impact of age related attitude information in a Go/NoGo association task that paired photographs of elderly or young faces with positive or negative words. Event related brain potentials showed an N200 (NoGo) component, which appeared earlier in runs which required similar responses for congruent stimulus pairings (e.g. respond to pictures of elderly faces or negative words) than for incongruent pairings (e.g. respond to elderly faces or positive words). As information processing leading to a certain attitude must precede differential brain activity according to the congruence of the paired words and faces, we show that this type of information is activated almost immediately following the structural encoding of the face, between 170 and 230 ms after onset of the face.

People strongly differ in their emotional reactions to potentially stressing and challenging environmental circumstances. Two classes of individual differences have independently been reported to contribute to such emotional vulnerability: an attentional bias to negative information and a variation in the serotonin transporter gene (5-HTTLPR). The present study was conducted to investigate the possibility that these cognitive and genetic markers interact in their prospective prediction of emotional reactivity to an extended and mild potential stressor. Changes in dysphoria and anxiety across their first university semester were measured in 120 students. Results indicate that attentional bias toward negative information on Week 1 of the semester significantly predicted cross-semester changes in both anxiety and dysphoria. For the latter, this predictive capacity depended on the 5-HTTLPR genotype. Specifically, only in homozygous carriers of the 5-HTTLPR short allele did attentional bias to negative information on Week 1 significantly predict cross-semester change in dysphoria. These results carry important theoretical and practical implications concerning the ability to identify individuals vulnerable to experiencing elevated emotional reactivity to potentially stressing life-events.

Previous research has revealed various relationships between self-reported personality traits and specific variations in genes influencing serotonergic and dopaminergic pathways. In recent studies, however, personality was repeatedly assessed by the use of more indirect measures, such as the implicit association test (IAT). This tool is assumed to access automatic associations, reflecting the sum of former dispositional behavior and experience. The present study aimed to identify potential genetic effects on personality-related associations measured by the IAT. In a sample of 96 women we found correlations between genetic variations of the serotonin and dopamine transporters (5-HTTLPR and DAT 3’-VNTR) and indirectly measured traits of anxiety and agentic extraversion. In detail, the 5-HTTLPR was linked to the anxiety IAT, whereas the DAT 3-’VNTR was associated with performance in the agentic-extraversion IAT. These findings point out genetic influences on personality-related associations and emphasize the usefulness of the IAT in research on the biological foundations of dispositions.

Summary Background Growing evidence suggests that the serotonin transporter polymorphism (5-HTTLPR) interacts with adverse environmental influences to produce an increased risk for the development of depression while the underlying mechanisms of this association remain largely unexplored. As one potential intermediate phenotype, we investigated alterations of hypothalamic–pituitary–adrenal (HPA) axis responses to stress in individuals with no history of psychopathology depending on both 5-HTTLPR and stressful life events. Methods Healthy male adults ( N = 100) were genotyped and completed a questionnaire on severe stressful life events (Life Events Checklist). To test for gene-by-environment interactions on endocrine stress reactivity, subjects were exposed to a standardized laboratory stress task (Public Speaking). Saliva cortisol levels were obtained at 6 time points prior to the stressor and during an extended recovery period. Results Subjects homozygous for the s-allele with a significant history of stressful life events exhibited markedly elevated cortisol secretions in response to the stressor compared to all other groups, indicating a significant gene-by-environment interaction on endocrine stress reactivity. No main effect of either 5-HTTLPR (biallelic and triallelic) or stressful life events on cortisol secretion patterns appeared. Conclusion This is the first study reporting that 5-HTTLPR and stressful life events interact to predict endocrine stress reactivity in a non-clinical sample. Our results underpin the potential moderating role of HPA-axis hyper-reactivity as a premorbid risk factor to increase the vulnerability for depression in subjects with low serotonin transporter efficiency and a history of severe life events.

Evidence suggests that a promoter polymorphism of the tryptophan-hydroxylase 2 gene (TPH2 -703 G/T) is associated with executive control functions. The current study aimed to clarify whether this relation is restricted to a purely cognitive domain or whether such an effect can also be observed in the processing of emotional material. In a sample of 89 student subjects, a 'cognitive' and an 'emotional' Stroop paradigm were applied to measure processing of cognitive and affective conflicts. Our results suggest an impact of the TPH2 -703 G/T polymorphism on executive control in both, the cognitive as well as the emotional task. In detail, homozygous carriers of the T allele showed decelerated responses in low-conflict conditions, pointing to a rather abnormal functioning of higher-order control mechanisms. Thus, the present investigation is consistent with previous behavioural studies and adds further evidence for the impact of serotonin at the interface of cognition and emotion.

We systematically compared different measures of attentional bias (i.e., reaction times, the N2pc component in the EEG, and explicit stimulus ratings) on their ability to reveal attentional engagement to threatening versus neutral facial stimuli in a Dot Probe Task and tested their relation to trait measures of general and social anxiety. We found that the N2pc component reflects a bias toward angry faces with excellent internal consistency. Similar results were obtained for explicit ratings. Reaction time (RT) differences, however, were not indicative of attentional biases and showed zero odd-even reliability. We further found that both higher (i.e., more negative) N2pc amplitudes and earlier peak latencies were associated with more severe symptoms of social anxiety even when controlling for general trait anxiety. The explicit rating biases were also specifically associated with social anxiety. Conversely, the RT bias was not related to social anxiety levels but to general trait anxiety. This highlights the importance of valid and reliable outcome measures for interventions such as attentional bias modification protocols. Mutual exclusivity of different bias operationalizations is discussed.

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.

Theta oscillations in the EEG have been shown to reflect ongoing cognitive processes related to mental effort. Here, we show that the pattern of theta oscillation in response to varying cognitive demands reflects stable individual differences in the personality trait epistemic motivation: Individuals with high levels of epistemic motivation recruit relatively more cognitive resources in response to situations possessing high, compared to low, cognitive demand; individuals with low levels do not show such a specific response. Our results provide direct evidence for the theory of the construct need for cognition and add to our understanding of the neural processes underlying theta oscillations. More generally, we provide an explanation how individual differences in personality traits might be represented on a neural level.

Background/Aims: Early and late event-related potential (ERP) responses, representing early subconscious and late motivational processes, were recorded for positive emotional words related to ‘wanting' and ‘liking', in dependence of the dopamine-related Taq1A genotype (ANKK1/DRD2). Research suggests that ‘wanting' as opposed to ‘liking' is related to dopaminergic processes. Therefore, it was hypothesized that risk allele carriers of the Taq1A polymorphism exhibit late ERP changes in reaction to words representing incentive motivation, i.e. ‘wanting' (word categories ‘lust' and ‘anticipation'), but not to words representing ‘liking' (‘closeness'). Methods: Seventy-two male participants performed an emotional-word Stroop task during EEG recording and were genotyped according to the Taq1A polymorphism of ANKK1/DRD2. Results: Positive emotional words related to anticipation and lust revealed blunted responses in the late positive potential (LPP) in carriers of the A1 allele, an effect absent in response to ‘liking'-related words. These differences were not evident in the earlier posterior negativity (EPN). Conclusion: As no differences in dependence of the Taq1A genotype were observed in reaction to ‘wanting'- and ‘liking'-related words in the EPN, but merely in the LPP, it can be assumed that incentive-motivational stimuli only modify motivation-related ERP responses in carriers of the A1 allele of the Taq1A polymorphism, indicating the role of dopamine in late ERP components.

A relatively new cognitive-affective training procedure, the Attentional Bias Modification (ABM) technique, is thought to decrease biases in the allocation of attention toward negative emotional stimuli. In two studies, we tested in samples of healthy students whether a single session of ABM has an influence on early orienting of spatial attention as indexed by the N2pc. Replicating previous studies, we found an occipitotemporal N2pc (180-300 ms) contralateral to angry versus neutral facial expressions, indicating that threatening faces automatically draw attention in early stages of stimulus processing. However, this N2pc effect did not significantly change during the ABM training session. Our results therefore indicate that a single session of ABM does not affect early attentional orienting. ABM effects reported in prior research may therefore have been mediated by later cognitive-affective mechanisms.

Prior research indicates that the feedback-related negativity (FRN) reflects a good versus bad evaluation of decision outcomes, which is insensitive to the local utilitarian relation between chosen and unchosen outcomes. We tested whether this negative finding holds when the chosen outcome has an objective value of zero and therefore a comparison with the unchosen outcome is needed to identify overall choice valence. Participants completed a gambling task in which chosen and unchosen options could result in monetary wins, losses, or breaking even. Results show that the FRN does not reflect local favorableness but rather a dichotomy of gain versus no-gain for both chosen and unchosen outcomes. In contrast, P300 amplitude appears to reflect motivational salience derived from counterfactual comparisons of chosen and unchosen outcomes. Based on our and prior findings, we propose a threefold taxonomy of contextual factors and their relation to the FRN.

Previous research has shown that receiving an unfair monetary offer in economic bargaining elicits also-called feedback negativity (FN). This scalp-recorded brain potential probably reflects a bad-vs-good evaluation in the medial frontal cortex and has been linked to fundamental processes of reinforcement learning. In the present study, we investigated whether the evaluative mechanism indexed by the FN is also involved in learning who is an unfair vs fair bargaining partner. An electroencephalogram was recorded while participants completed a computerized version of the Ultimatum Game, repeatedly receiving fair or unfair monetary offers from alleged other participants. Some of these proposers were either always fair or always unfair in their offers. In each trial, participants first saw a portrait picture of the respective proposer before the monetary offer was presented. Therefore, the faces could be used as predictive cues for the fairness of the pending offers. We found that not only unfair offers themselves induced a FN, but also (over the task) faces of unfair proposers. Thus, when interaction partners repeatedly behave in an unfair way, their faces acquire a negative valence, which manifests in a basal neural mechanism of bad-vs-good evaluation.

The feedback negativity (FN) has been repeatedly linked to expectancies about decision outcomes. Sequential outcome order is likely to influence such expectancies but has been widely disregarded. We therefore investigated whether the three-trial order of decision outcomes in a gambling task influences the FN as well as the P200 and P300. All three deflections were not only influenced by the outcome valence of the current trial but also by the outcomes of the two preceding trials. In detail, the FN and P300 to any current trial outcome were largest when the outcomes in the two preceding trials had an opposite valence. The P200 was highest in the context of two directly preceding wins, indicating that it may reflect representations of local outcome history. Our findings demonstrate that neural systems involved in decision outcome processing dynamically and continuously integrate the local outcome history for the evaluation of present outcomes.

Fear learning is a crucial process in the pathogeneses of psychiatric disorders, which highlights the need to identify specific factors contributin gt o interindividual variation. We hypothesized variation in the serotonin transporter gene (5-HTTLPR) and stressful life events (SLEs) to be associated with neural correlates of fear conditioning in a sample of healthy male adults (n ¼ 47). Subjects were exposed to a differential fear conditioning paradigm after being preselected regarding 5-HTTLPR genotype and SLEs. Individual differences in brain activity as measured by functional magnetic resonance imaging (fMRI), skin conductance responses and preference ratings were assessed. We report significant variation in neural correlates of fear conditioning as a function of 5-HTTLPR genotype. Specifically, the conditioned stimulus (CS þ ) elicited elevated activity within the fear-network (amygdala, insula, thalamus, occipital cortex) in subjects carrying two copies of the 5-HTTLPR S 0 allele. Moreover, our results revealed preliminary evidence for a significant gene-by-environment interaction, such as homozygous carriers of the 5-HTTLPR S 0 allele with a history of SLEs demonstrated elevated reactivity to the CS þ in the occipital cortex and the insula. Our findings contribute to the current debate on 5-HTTLPR x SLEs interaction by investigating crucial alterations on an intermediate phenotype level which may convey an elevated vulnerability for the development of psychopathology.

According to recent theoretical approaches dispositional anxiety is fundamentally linked to neural mechanisms of cognitive control (Braver et al., 2007; Eysenck et al., 2007). The present study was conducted to further investigate this topic by focusing on the relation between trait anxiety, conflict-processing and dynamic adjustments in attentional allocation. Participants completed a modified version of the face-word Stroop task while an electroencephalogram was recorded. We analyzed behavioral and electrophysiological correlates of conflict processing and conflict-driven modulations in target and distractor processing. Anxiety was not related to general conflict-sensitivity but to individual differences in conflict-driven adjustments in attentional allocation: following a high level of stimulus-response conflict, highly anxious participants allocated more attentional resources to the processing of predominantly task-relevant information and withdrew attention from the processing of predominantly task-irrelevant information. Thus, trait anxiety appears to be closely related to individual differences in dynamic adjustments of attentional control.

Recently, it has been assumed that high- and low-trait-anxious subjects differ in the way they use fundamental cognitive control mechanisms. The present study was designed to further elucidate this topic by focusing on trial-to-trial adjustments in neuronal correlates of conflict processing. An electroencephalogram was recorded while subjects (N = 71) performed a gender discrimination version of the Stroop task. The conflict-related N400 of the ERP was influenced by an interaction between trait anxiety and previous trial context: An additional negative-going deflection in the N400 range was observed when the target-distractor pairing of the directly preceding trial was incongruent, but only in highly anxious subjects. Thus, highly anxious subjects appear to more strongly engage neuronal modules involved in conflict monitoring when previously exposed to a high stimulus-response conflict. These results indicate that trait anxiety is crucially linked to the way the cognitive system dynamically adapts to recent demands.

Catecholamines modulate endocrine stress reactivity by affecting regulatory influences of extra-hypothalamic brain structures on hypothalamus-pituitary-adrenal (HPA)-axis. Therefore, we aimed to investigate combined effects of functional allelic variations that affect dopamine availability in both cortical (COMT Val¹⁵⁸Met polymorphism) and subcortical (DAT1 VNTR) brain regions on HPA-axis reactivity to psychosocial stress. By using a standardized laboratory stress task (public speaking) we obtained saliva cortisol samples during stress exposure and an extended recovery period in 100 healthy male adults. We report for the first time significant epistasis between COMT Val¹⁵⁸Met and DAT1 VNTR on cortisol response patterns. Subjects homozygous for both the Met¹⁵⁸ and the 10-repeat allele of DAT1 VNTR were characterized by markedly elevated cortisol reactivity and impaired stress recovery compared to all other groups. Our results indicate a crucial role of functional genetic variants within the dopaminergic system in the modulation of HPA-axis response patterns and highlight the need to investigate combined effects of specific candidate genes on stress-related endophenotypes.

Summary Background Growing evidence suggests that individual differences in HPA-axis reactivity to psychosocial stress are partly due to heritable influences. However, knowledge about the role of specific genetic variants remains very limited to date. Since brain-derived neurotrophic factor (BDNF) not only exhibits neurotrophic actions but is also involved in the regulation of hypothalamic neuropeptides, we investigated the role of a common functional polymorphism within the BDNF gene (BDNF Val66Met) in the context of endocrine and cardiovascular stress reactivity. Methods Healthy male adults ( N = 100) were genotyped and exposed to a standardized laboratory stress task (Public Speaking). Saliva cortisol and self-reported mood levels were obtained at 6 time points prior to the stressor and during an extended recovery period. Furthermore, heart rate reactivity as an indicator of sympathetic activation was monitored continuously during the experimental procedure. Results We report a small, but significant effect of the BDNF Val66Met polymorphism on stress reactivity. More precisely, carriers of the met-allele showed a significantly attenuated HPA-axis and cardiovascular reactivity to the psychosocial stressor compared to subjects with the val/val genotype. Furthermore, the diminished physiological response in met-allele carriers was also attended by significantly lower self-reported ratings of perceived stress and nervousness. Conclusion Our findings of a diminished endocrine and cardiovascular stress response in healthy male adults is consistent with a previously published study and adds further evidence for a crucial role of the BDNF Val66Met polymorphism in the modulation of stress reactivity.

Serotonin (5-HT) and testosterone (T) have both been implicated in the regulation of aggression. Findings in humans however are very inconclusive, with respect to main effects of either system. Animal models implicate T to modulate 5-HT system activity, and furthermore have shown behaviorally relevant interactions of T and 5-HT with respect to aggression. We tested for associations between habitual T-level and 5-HT system activity, as well as behaviorally relevant interactions of T and 5-HT with respect to trait aggression in 48 healthy male and female subjects. 5-HT activity was measured by means of neuroendocrine challenge paradigm with S-citalopram. T-levels were measured in saliva samples. Trait aggression was assessed by self-report measures. T-levels were not associated with indices of central 5-HT activity. Results showed significant interaction effects between 5-HT and T for trait aggression in men only (p

During past years the 5-HT(1A) C(-1019)G polymorphism has been associated with vulnerability to depression, anxiety-disorder and personality traits related to negative emotionality (e.g. neuroticism). Many of these studies focused on case-control comparisons or associations between genetic markers and personality traits assessed by the use of questionnaires. In contrast, overt behaviour and physiological measures in experimental paradigms, although very promising, have seldom been the focus of studies investigating the role of the 5-HT(1A) polymorphism for behaviour and psychopathology. To fill this gap, we examined the relationship between the 5-HT(1A) C(-1019)G polymorphism and reaction times (in a reward/punishment paradigm) as well as electrodermal activity, as a marker of autonomic arousal, in 123 healthy subjects. This paradigm seems very promising, as sensitivity to punishment in particular, is strongly associated to traits related to negative emotionality. Carriers of the GG genotype, which is related to increased expression of 5-HT(1A) autoreceptors, exhibited increased reaction times when they were able to win money (reward condition). In direct contrast to the reward condition, these subjects show faster reaction times in the punishment condition (losing money). Moreover, GG carriers are characterized by an enhanced electrodermal activity in all experimental conditions (win, lose and verbal feedback). Finally, the reaction-time pattern mentioned was related to higher scores on negative emotionality as revealed by self-reports. These findings demonstrate for the first time that the 5-HT(1A) polymorphism is related to personality on the level of a triadic approach including behaviour, physiology and self-reports.

The 5-HTTLPR is an insertion/deletion polymorphism in the promoter region of the serotonin transporter gene. Prior research has revealed associations between the short-allele variant of this polymorphism, enhanced self-reported negative emotionality, and hypersensitivity of fear relevant neural circuits. In a sample of 50 healthy women we examined the role of 5-HTTLPR for cognitive-affective processing of phylogenetical fear-relevant stimuli (spiders) in a dot probe task. In contrast to homozygote long-allele carriers (11), participants carrying at least 1 short allele (ss and sl) selectively shifted attention toward pictures of spiders, when these were presented for a duration of 2,000 ms. These results argue for an involvement of 5-HTTLPR in cognitive processing of threatening stimuli and thus, underpin its general role for individual differences in negative affect.