Political Orientation as Psychological Defense or Basic Disposition? A Social Neuroscience Examination

Psychological views on political orientation generally agree that conservatism is associated with negativity bias but disagree on the form of that association. Some view conservatism as a psychological defense that insulates from negative stimuli and events. Others view conservatism as a consequence of increased dispositional sensitivity to negative stimuli and events. Further complicating matters, research shows that conservatives are sometimes more and sometimes less sensitive to negative stimuli and events. The current research integrates these opposing views and results. We reasoned that conservatives should typically be less sensitive to negative stimuli if conservative beliefs act as a psychological defense. However, when core components of conservative beliefs are threatened, the psychological defense may fall, and conservatives may show heightened sensitivity to negative stimuli. In two ERP studies, participants were randomly assigned to either an ostensibly real economic threat or a nonthreatening control condition. To measure reactivity to negative stimuli, we indexed the P3 component to aversive white noise bursts in an auditory oddball paradigm. In both studies, the relationship between increased conservatism and P3 mean amplitude was negative in the control condition but positive in threat condition (this relationship was stronger in Study 2). In Study 2, source localization of the P3 component revealed that, after threat, conservatism was associated with increased activity in the anterior cingulate cortex and dorsomedial prefrontal cortex, regions associated with conflict-related processes. These results demonstrate that the link between conservatism and negativity bias is context-dependent, i.e., dependent on threat experiences.

In Identifying the Source of the Incongruent Effect

Emotional signals from the face and body are normally perceived as an integrated whole in everyday life. Previous studies have revealed an incongruent effect which refers to distinctive behavioral and neural responses to emotionally congruent versus incongruent face-body compounds. However, it remains unknown which kind of the face-body compounds caused the incongruence effect. In the present study, we added neutral face and neutral body stimuli to form new face-body compounds. Forty subjects with normal or corrected-to-normal vision participated in this experiment. By comparing the face-body compounds with emotional conflict and face-body compounds with neutral stimuli, we could investigate the source of the incongruent effect. For both behavioral and event-related potential (ERP) data, a 2 (bodily expression: happiness, fear) × 2 (congruence: congruent, incongruent) repeated-measure analysis of variance (ANOVA) was performed to re-investigate the incongruent effect and a 3 (facial expression: fearful, happy, neutral) × 3 (bodily expression: fearful, happy, neutral) repeated-measure ANOVA was performed to clarify the source of the incongruent effect. As expected, both behavioral and ERP results have successfully repeated the incongruent effect. Specifically, the behavioral data showed that emotionally congruent versus incongruent face-body compounds were recognized more accurately ( p < .05). The ERP component of N2 was modulated by the emotional congruency between the facial and bodily expression showing that the emotionally incongruent compounds elicited greater N2 amplitudes than emotionally congruent compounds ( p < .05). No incongruent effect was found for P1 or P3 component ( p = .079, p = .99, respectively). Furthermore, by comparing the emotionally incongruent pairs with the neutral baseline, the present study suggests that the source of the incongruent effect might be from the happy face-fearful body compounds. We speculate that the emotion expressed by the fearful body was much more intensive than the emotion expressed by the happy body and thus caused a stronger interference in judging the facial expressions.

Electrophysiological evidence of different neural processing between visual and audiovisual inhibition of return

Inhibition of return (IOR) refers to the slower response to targets appearing on the same side as the cue (valid locations) than to targets appearing on the opposite side as the cue (invalid locations). Previous behaviour studies have found that the visual IOR is larger than the audiovisual IOR when focusing on both visual and auditory modalities. Utilising the high temporal resolution of the event-related potential (ERP) technique we explored the possible neural correlates with the behaviour IOR difference between visual and audiovisual targets. The behavioural results revealed that the visual IOR was larger than the audiovisual IOR. The ERP results showed that the visual IOR effect was generated from the P1 and N2 components, while the audiovisual IOR effect was derived only from the P3 component. Multisensory integration (MSI) of audiovisual targets occurred on the P1, N1 and P3 components, which may offset the reduced perceptual processing due to audiovisual IOR. The results of early and late differences in the neural processing of the visual IOR and audiovisual IOR imply that the two target types may have different inhibitory orientation mechanisms.

Are They Calling My Name? Attention Capture Is Reflected in the Neural Tracking of Attended and Ignored Speech

Difficulties in selectively attending to one among several speakers have mainly been associated with the distraction caused by ignored speech. Thus, in the current study, we investigated the neural processing of ignored speech in a two-competing-speaker paradigm. For this, we recorded the participant’s brain activity using electroencephalography (EEG) to track the neural representation of the attended and ignored speech envelope. To provoke distraction, we occasionally embedded the participant’s first name in the ignored speech stream. Retrospective reports as well as the presence of a P3 component in response to the name indicate that participants noticed the occurrence of their name. As predicted, the neural representation of the ignored speech envelope increased after the name was presented therein, suggesting that the name had attracted the participant’s attention. Interestingly, in contrast to our hypothesis, the neural tracking of the attended speech envelope also increased after the name occurrence. On this account, we conclude that the name might not have primarily distracted the participants, at most for a brief duration, but that it alerted them to focus to their actual task. These observations remained robust even when the sound intensity of the ignored speech stream, and thus the sound intensity of the name, was attenuated.

Mobile ear-EEG to study auditory attention in everyday life

Most research investigating auditory perception is conducted in controlled laboratory settings, potentially restricting its generalizability to the complex acoustic environment outside the lab. The present study, in contrast, investigated auditory attention with long-term recordings (> 6 h) beyond the lab using a fully mobile, smartphone-based ear-centered electroencephalography (EEG) setup with minimal restrictions for participants. Twelve participants completed iterations of two variants of an oddball task where they had to react to target tones and to ignore standard tones. A rapid variant of the task (tones every 2 s, 5 min total time) was performed seated and with full focus in the morning, around noon and in the afternoon under controlled conditions. A sporadic variant (tones every minute, 160 min total time) was performed once in the morning and once in the afternoon while participants followed their normal office day routine. EEG data, behavioral data, and movement data (with a gyroscope) were recorded and analyzed. The expected increased amplitude of the P3 component in response to the target tone was observed for both the rapid and the sporadic oddball. Miss rates were lower and reaction times were faster in the rapid oddball compared to the sporadic one. The movement data indicated that participants spent most of their office day at relative rest. Overall, this study demonstrated that it is feasible to study auditory perception in everyday life with long-term ear-EEG.

The hierarchical sensitivity to social misalignment during decision-making under uncertainty

Social misalignment occurs when a person’s attitudes and opinions deviate from those of others. We investigated how individuals react to social misalignment in risky (outcome probabilities are known) or ambiguous (outcome probabilities are unknown) decision contexts. During each trial, participants played a forced-choice gamble, and they observed the decisions of four other players after they made a tentative decision, followed by an opportunity to keep or change their initial decision. Behavioral and event-related potential data were collected. Behaviorally, the stronger the participants’ initial preference, the less likely they were to switch their decisions, whereas the more their decisions were misaligned with the majority, the more likely they were to switch. Electrophysiological results showed a hierarchical processing pattern of social misalignment. Misalignment was first detected binarily (i.e. match/mismatch) at an early stage, as indexed by the N1 component. During the second stage, participants became sensitive to low levels of misalignment, which were indexed by the feedback-related negativity. The degree of social misalignment was processed in greater detail, as indexed by the P3 component. Moreover, such hierarchical neural sensitivity is generalizable across different decision contexts (i.e. risky and ambiguous). These findings demonstrate a fine-grained neural sensitivity to social misalignment during decision-making under uncertainty.

Assessing Cognitive Capacity by P3 During a Complex Manual Control Task

Our aim was to adapt a classical P3 method to assess the free cognitive capacity during spacecraft docking training in space. Electroencephalogram (EEG) measurement in space is limited by several conditions. Based on experience with our own EEG experiments on MIR and ISS, we decided to use dry electrodes and restricted the electrode placement to the forehead. We examined whether P3 can be reliably obtained under these conditions. Subjects had to perform a manually controlled docking task simultaneously with an acoustic monitory task. The P3 component was evoked by the acoustic stimuli of the secondary task. Twenty-six subjects participated in this study, situated in a space simulation on earth. After a familiarization session, they performed the docking tasks at three difficulty levels: low, medium, and difficult. In the secondary task, subjects had to discriminate between a low (750 Hz) and a high (1,000 Hz) tone, which differed in probability of 90% and 10%, respectively. The subjects had to count the high tone and after 10 relevant tones and had to give a voice command to a power supply configuration. P3 amplitude was largest and the latency shortest during the medium difficult task. A decision matrix based on differences between the relevant and irrelevant P3 was calculated for each subject and each task. The results suggest that P3 can be recorded during a complex manual control task and can be used to assess individual free cognitive capacity.

A neural turning point - the EEG P3 component tracks unfolding changes of mind

The ability to change one’s mind is a key feature of human cognition. Yet, the neural mechanisms underpinning our capacity to change our minds remain poorly understood. Here, we investigated the neural correlates of evidence accumulation and changes of mind in a two-step sequential sampling task. Participants provided a first, quick guess regarding the relative frequencies of target letters in a visual stream, followed by a slower, more deliberate decision. We found that the P3 amplitude evoked by successive target letters tracks an internal signed decision variable and predicts choices on a single-trial level. Moreover, this neural decision variable offers new insights into the dynamics of changes of mind. In particular, we show that the start of evidence accumulation after the early decision constitutes a neural turning point: the P3 evoked by the first letter contrary to the initial decision can be used to predict subsequent changes of mind. Our results highlight a critical interaction between the processing of external evidence and endogenous modulations of decisional parameters that facilitate reversing an original decision.

Unexpected Sounds Nonselectively Inhibit Active Visual Stimulus Representations

The brain’s capacity to process unexpected events is key to cognitive flexibility. The most well-known effect of unexpected events is the interruption of attentional engagement (distraction). We tested whether unexpected events interrupt attentional representations by activating a neural mechanism for inhibitory control. This mechanism is most well characterized within the motor system. However, recent work showed that it is automatically activated by unexpected events and can explain some of their nonmotor effects (e.g., on working memory representations). Here, human participants attended to lateralized flickering visual stimuli, producing steady-state visual evoked potentials (SSVEPs) in the scalp electroencephalogram. After unexpected sounds, the SSVEP was rapidly suppressed. Using a functional localizer (stop-signal) task and independent component analysis, we then identified a fronto-central EEG source whose activity indexes inhibitory motor control. Unexpected sounds in the SSVEP task also activated this source. Using single-trial analyses, we found that subcomponents of this source differentially relate to sound-induced SSVEP changes: While its N2 component predicted the subsequent suppression of the attended-stimulus SSVEP, the P3 component predicted the suppression of the SSVEP to the unattended stimulus. These results shed new light on the processes underlying fronto-central control signals and have implications for phenomena such as distraction and the attentional blink.

Hits-Based Quantitative Characterization of SOBI-Recovered P3 Network Configuration: an EEG Source-Imaging Study

One frequently studied biomarker for health and disease conditions is the P3 component extracted from scalp recorded electroencephalography (EEG). The spatial origin of this significant neural signal is known to be distributed, typically involving large regions of the cerebral cortex as well as subcortical structures. Unlike the temporal characterization of the P3 by amplitude or latency measures from event-related potentials (ERPs), the spatial characterization of the P3 component is relatively rare, typically qualitative, and often reported as differences between populations (group differences between healthy controls and clinical groups). Here we introduce a novel approach to quantitatively characterize the spatial origin of the P3 component by (1) applying second-order blind identification (SOBI) to continuous, high-density EEG data to extract the P3 component, (2) modeling the underlying generators of the SOBI P3 component as a set of equivalent current dipoles (ECDs) in Talairach space using BESA; (3) using the application Talairach Client to determine the “hits” associated with the anatomical structures at three level of resolution (lobe, gyrus, and cell type). We show that the hits information provided by Talairach Client can enable a quantitative characterization of the spatial configuration of the network underlying the P3 component (P3N) via two quantities: cross-individual reliability (or consistency) of a given brain structure as a part of the P3N, and within-individual contribution of a given brain structure to the whole P3N network. We suggest that this method may be used to further differentiate individuals in the absence of differences in P3 amplitude or latency, or when scientific questions or practical application cannot be supported by a yes-no answer regarding the source of a P3 component. Finally, application of our method to a group of 13 participants revealed that frontal structures, particularly BA10, play a special role in the function of a global cortical network underlying novelty processing.