The effect of panic disorder versus anxiety sensitivity on event-related potentials during anticipation of threat

Unpredictable threat increases early event-related potential amplitudes and cardiac acceleration: A brain-heart coupling study

In the face of unpredictable threat, rapid processing of external events and behavioral mobilization through early psychophysiological responses are crucial for survival. While unpredictable threat generally enhances early processing, it would seem adaptive to particularly increase sensitivity for unexpected events as they may signal danger. To examine this possibility, n = 77 participants performed an auditory oddball paradigm and received unpredictable shocks in threat but not in safe contexts while a stream of frequent (standard) and infrequent (deviant) tones was presented. We assessed event-related potentials (ERP), heart period (HP), and time-lagged within-subject correlations of single-trial EEG and HP (cardio-EEG covariance tracing, CECT) time-locked to the tones. N1 and P2 ERP amplitudes were generally enhanced under threat. The P3 amplitude was enhanced to deviants versus standards and this effect was reduced in the threat condition. Regarding HP, both threat versus safe and unexpected versus expected tones led to stronger cardiac acceleration, suggesting separate effects of threat and stimulus expectancy on HP. Finally, CECTs revealed two correlation clusters, indicating that single-trial EEG magnitudes in the N1/P2 and P3 time-windows predicted subsequent cardiac acceleration. The current results show that an unpredictable threat context enhances N1 and P2 amplitudes and cardiac acceleration to benign auditory stimuli. They further suggest separable cortical correlates of different effects on cardiac activity: an early N1/P2 correlate associated with threat-effects on HP and a later P3 correlate associated with expectedness-effects. Finally, the results indicate that unpredictable threat attenuates rather than enhances the processing of unexpected benign events during the P3 latency.

Neurocognitive Mechanisms Underlying Attention Bias Towards Pain: Evidence From a Drift-Diffusion Model and Event-Related Potentials

Although combining computational modeling with event-related potentials (ERPs) can precisely characterize neurocognitive processes involved in attention bias, it has yet to be applied in the context of pain. Here, a hierarchical drift-diffusion model (DDM) along with ERPs was used to characterize the neurocognitive mechanisms underlying attention bias towards pain. A spatial cueing paradigm was adopted, in which the locations of targets were either validly or invalidly predicted by spatial cues related to pain or nonpain signals. DDM-derived nondecision time was shorter for targets validly cued by pain signals than by nonpain signals, thus indicating speeded attention engagement towards pain; drift rate was slower for targets invalidly cued by pain signals than by nonpain signals, reflecting slower attention disengagement from pain. The facilitated engagement towards pain was partially mediated by the enhanced lateralization of cue-evoked N1 amplitudes, which relate to the bottom-up, stimulus-driven processes of detecting threatening signals. On the other hand, the retarded disengagement from pain was partially mediated by the enhanced target-evoked anterior N2 amplitudes, which relate to the top-down, goal-driven processes of conflict monitoring and behavior regulating. These results demonstrated that engagement and disengagement components of pain-related attention bias are governed by distinct neurocognitive mechanisms. However, it remains possible that the findings are not pain-specific, but rather, are related to threat or aversiveness in general. This deserves to be further examined by adding a control stimulus modality. PERSPECTIVE: This study characterized the neurocognitive processes involved in attention bias towards pain through combining a hierarchical DDM and ERPs. Our results revealed distinctive neurocognitive mechanisms underlying engagement and disengagement components of attention bias. Future studies are warranted to examine whether our findings are pain-specific or not.

Don't worry, it won't be fine. Contributions of worry and anxious arousal to startle responses and event-related potentials in threat anticipation

A widely shared framework suggests that anxiety maps onto two dimensions: anxious apprehension and anxious arousal. Previous research linked individual differences in these dimensions to differential neural response patterns in neuropsychological, imaging, and physiological studies. Differential effects of the anxiety dimensions might contribute to inconsistencies in prior studies that examined neural processes underlying anxiety, such as hypersensitivity to unpredictable threat. We investigated the association between trait worry (as a key component of anxious apprehension), anxious arousal, and the neural processing of anticipated threat. From a large online community sample (N = 1,603), we invited 136 participants with converging and diverging worry and anxious arousal profiles into the laboratory. Participants underwent the NPU-threat test with alternating phases of unpredictable threat, predictable threat, and safety, while physiological responses (startle reflex and startle probe locked event-related potential components N1 and P3) were recorded. Worry was associated with increased startle responses to unpredictable threat and increased attentional allocation (P3) to startle probes in predictable threat anticipation. Anxious arousal was associated with increased startle and N1 in unpredictable threat anticipation. These results suggest that trait variations in the anxiety dimensions shape the dynamics of neural processing of threat. Specifically, trait worry seems to simultaneously increase automatic defensive preparation during unpredictable threat and increase attentional responding to threat-irrelevant stimuli during predictable threat anticipation. The current study highlights the utility of anxiety dimensions to understand how physiological responses during threat anticipation are altered in anxiety and supports that worry is associated with hypersensitivity to unpredictable, aversive contexts.

Fear of negative evaluation modulates the processing of social evaluative feedback with different valence and contexts

Fear of negative evaluation (FNE) is a susceptible and maintaining factor of social anxiety disorders. However, the question, how people process negative evaluation is influenced by individual differences in FNE, is poorly understood. To clarify the habitual processing characteristics of individuals with different levels of FNE, electroencephalography was recorded when two groups of participants with high FNE (hFNE) and low FNE (lFNE) performed a social evaluation perception task in which the feedback context/source (human vs. a computer) and valence (thumb-up/like vs. thumb-down/dislike) were manipulated. We found effects of feedback source and valence on N1, P2, and P3, which reflect early attention, integrated perception, and elaborative processing, respectively, as well as general reward effects on reward positivity (RewP) across contexts. Importantly, compared to the lFNE group, the hFNE group showed larger midfrontal N1 and theta oscillation in response to negative feedback indicating dislike (vs. like), and also showed larger P3. These findings suggest that individuals with hFNE are more attentional vigilance to negative (vs. positive) social feedback, implying that individuals with different levels of FNE assign different implicit threat values to social-evaluation threat stimuli.

Event-related potentials to acoustic startle probes during unpredictable threat are associated with individual differences in intolerance of uncertainty

Individual differences in sensitivity to unpredictable threat may be a critical mechanism for internalizing psychopathology phenotypes. The present study examined whether the startle probe-elicited N100 and P300 during unpredictable threat - two event-related potentials indexing early and elaborative attentional processing of unpredictable threat - may be endophenotypes for internalizing psychopathology, including fear and distress/misery disorders and intolerance of uncertainty (IU), a clinical trait that is transdiagnostically associated with internalizing disorders. A large sample of adult siblings (N = 375) completed the no, predictable, and unpredictable threat task, during which the N100 and P300 were recorded. Relative to the no threat condition, N100 was more strongly enhanced in anticipation of unpredictable than predictable threat while P300 was suppressed to both predictable and unpredictable threat. While neither N100 enhancement nor P300 suppression to unpredictable threat was associated with fear or distress/misery disorders, they were negatively linked to inhibitory IU (a facet of IU). Thus, individuals high in inhibitory IU showed reduced attentional engagement with the threatening context when it was unpredictable. Further, N100 enhancement and, to a lesser degree, P300 suppression to unpredictable threat showed familial aggregation - a key criterion for determining whether a biomarker is an endophenotype. In sum, N100 enhancement and P300 suppression to unpredictable threat may be endophenotypes for dimensional measures of internalizing psychopathology.

The roles of disgust sensitivity and anxiety sensitivity in attentional bias in dental anxiety

Individuals with dental anxiety show biased attentional processing of threat- and dental-related information. Disgust sensitivity and anxiety sensitivity are both associated with dental fears and attentional biases. Whereas disgust sensitivity is generally associated with attentional avoidance (Armstrong et al., 2014), anxiety sensitivity may be associated with attentional engagement (Keogh et al., 2001a). Elucidating the role of these constructs in dental anxiety-relevant attentional biases could inform theoretical models and/or intervention recommendations. Participants (N = 51) with high dental anxiety completed a Posner paradigm to assess attentional biases to dental versus neutral stimuli. We examined whether disgust sensitivity and anxiety sensitivity moderated degree of attentional bias. Results indicated that both disgust sensitivity (mutilation subscale) and anxiety sensitivity (physical concerns subscale) statistically moderated degree of attentional bias at trend level, and in opposite directions. Simple effects analyses further indicated that disgust sensitivity regarding mutilation was associated with less attentional bias toward dental relative to neutral stimuli, potentially indicating attentional avoidance, and remained so when adjusting for anxiety sensitivity. In contrast, simple effects analysis indicated that anxiety sensitivity regarding physical concerns was not associated with magnitude of attentional bias. If replicated, findings highlight the potential role of disgust in dental anxiety.

Neural Processing of Cognitive Control in an Emotionally Neutral Context in Anxiety Patients

Impaired cognitive control plays a crucial role in anxiety disorders and is associated with deficient neural mechanisms in the fronto-parietal network. Usually, these deficits were found in tasks with an emotional context. The present study aimed at investigating electrophysiological and vascular signatures from event-related brain potentials (ERPs) and functional near-infrared spectroscopy (fNIRS) in anxiety patients versus healthy controls during an inhibition task integrated in an emotionally neutral context. Neural markers were acquired during the completion of a classical Eriksen flanker task. The focus of data analysis has been the ERPs N200 and P300 and fNIRS activations in addition to task performance. No behavioral or neural group differences were identified. ERP findings showed a larger N2pc and a delayed and reduced P300 for incongruent stimuli. The N2pc modulation suggests the reorienting of attention to salient stimuli, while the P300 indicates longer lasting stimulus evaluation processes due to increased task difficulty. FNIRS did not result in any significant activation potentially suggesting a contribution from deeper brain areas not measurable with fNIRS. The missing group difference in our non-emotional task indicates that no generalized cognitive control deficit but rather a more emotionally driven deficit is present in anxiety patients.

Facial emotion perception in young female students with subsyndromal panic disorder. Behavioral and ERP study

This study aimed to examine the behavioral and neural correlates of facial emotion recognition in young women with subsyndromal panic disorder (SPD). In the experiment 15 non-medicated women with SPD and 17 matched healthy controls were tasked with recognizing angry, fearful, happy, and neutral facial expressions, and accuracy, reaction time (RT), and event-related potentials (ERPs) were recorded. Significant between-group differences in behavioral characteristics (accuracy of emotion recognition and RT) were not found, however, the SPD subjects demonstrated a slower response to fearful expressions compared to neutral and happy expressions. More distinct between-group differences were observed for the EPRs. The SPD subjects demonstrated increased amplitudes of the P100 ERP component in the occipital area and the P200 component over the occipital and temporal regions. In the frontal regions the SPD group showed a greater amplitude of the N200 component and also an increased negativity 350-450 ms after stimulus presentation. According to the dipole source modeling data, the SPD subjects showed enhanced activation in the extra-striate cortex which increased in intensity when angry and fearful faces were presented. Thus, young women with SPD which manifested in infrequent panic attacks showed significant alterations in ERP characteristics of emotional processing, which may be considered as a more sensitive indicator of early-stage panic disorder than the observed behavioral measures.

From Uncertainty to Anxiety: How Uncertainty Fuels Anxiety in a Process Mediated by Intolerance of Uncertainty

Uncertainty about future events may lead to worry, anxiety, even inability to function. The highly related concept-intolerance of uncertainty (IU)-emerged in the early 1990s, which is further developed into a transdiagnostic risk factor in multiple forms of anxiety disorders. Interests in uncertainty and intolerance of uncertainty have rapidly increased in recent years; little is known about the construct and phenomenology of uncertainty and IU and the association between them. In an attempt to reveal the nature of two concepts, we reviewed broad literature surrounding uncertainty and intolerance of uncertainty (IU). We followed the process in which the whole IU theory developed and extended, including two aspects: (1) from uncertainty to intolerance of uncertainty and (2) definition of uncertainty and intolerance of uncertainty, and further concluded uncertainty fuels to negative emotions, biased expectancy, and inflexible response. Secondly, this paper summarized the experimental research concerning uncertainty and IU, consisted of three parts: (1) uncertainty-based research, (2) measurements of IU, and (3) domain-specific IU. Lastly, we pointed out what remains unknown and needed to be investigated in future research. This result provides a comprehensive overview in this domain, enhancing our understanding of uncertainty and IU and contributing to further theoretical and empirical explorations.

The altered early components and the decisive later process underlying attention bias modification in social anxiety: evidence from event-related potentials

Attention bias modification (ABM) is a potential intervention in relieving social anxiety symptoms, while its underlying neural mechanisms are not yet understood. The current study included 63 college students with social anxiety. Participants were assigned to the attention modification program (AMP, n = 20), the attention control condition (ACC, n = 20) and the passive waiting group (PW, n = 23). Questionnaires and the emotional Stroop task with EEG recordings were used to assess whether and how the 4-week ABM period affected emotional symptoms and specific emotional processing. Results showed that the two training groups (AMP and ACC) produced comparable emotional improvements and both showed a decrease in negative bias compared with the PW group. The ERP results indicated that despite no significant ERP changes in the PW group, the ACC group exhibited a greater N1, whereas the AMP group exhibited a reduced VPP at the post-test stage compared to the pre-test stage. Besides, both training groups showed a similar late positive potential (LPP) reduction. Notably, the reduction in LPP was positively correlated with behavioral and symptom improvement. Thus, manipulations unique to ABM (face-target contingency) primarily modulate the early attention distribution of material-related stimuli. However, the clinical benefits of attention training may be due to later cognitive-affective mechanisms.

Startle during threat longitudinally predicts functional impairment independent of DSM diagnoses

Heightened responsivity to unpredictable, and perhaps predictable, threat characterizes some internalizing disorders and may be vulnerability factors for psychopathology as well. However, few studies have directly tested whether individual differences in unpredictable and/or predictable threat responding longitudinally predict symptoms of psychopathology and functional outcomes. Examining functioning is particularly important given that functioning is separable from symptoms of psychopathology. The present study examined whether electromyography startle measures of predictable and/or unpredictable threat responding was associated with interviewer-assessed symptoms of internalizing psychopathology and functional impairment at baseline (n = 409) and one-year follow-up (n = 104). Elevated startle responding to unpredictable and predictable threat longitudinally predicted a worsening of functioning over time and this effect was independent of change of symptoms over time. Importantly, threat responding at baseline predicted functional impairment during the follow-up independent of the effects of DSM-defined fear-based (e.g., panic disorder) or distress-misery (e.g., major depressive disorder) internalizing disorders. These findings provide initial support for the incremental validity of neurobiological vulnerability markers of threat responding over and above DSM disorders and highlight the importance of distinguishing functional outcomes from symptom outcomes.

Hypervigilance during anxiety and selective attention during fear: Using steady-state visual evoked potentials (ssVEPs) to disentangle attention mechanisms during predictable and unpredictable threat

Anxiety is induced by unpredictable threat, and presumably characterized by enhanced vigilance. In contrast, fear is elicited by imminent threat, and leads to phasic responses with selective attention. In order to investigate attention mechanisms and defensive responding during fear and anxiety, we employed an adaptation of the NPU-threat test and measured cortical (steady-state visual evoked potentials, ssVEPs), physiological (heart rate, HR), and subjective responses (ratings) to predictable (fear-related) and unpredictable (anxiety-related) threat in 42 healthy participants. An aversive unconditioned stimulus (US, loud noise) was 100% predicted by a cue (predictable P-cue) in one context (predictable P-context), but appeared unpredictably within a different context (unpredictable U-context, U-cue), while it was never delivered in a neutral safe context (N-cue, N- context). In response to predictable threat (P-cue), increased ssVEP amplitudes and accelerated HR were found. Both predictable and unpredictable contexts yielded increased ssVEP amplitudes compared to the safe context. Interestingly, in the unpredictable context participants showed longer-lasting visuocortical activation than in the predictable context, supporting the notion of heightened vigilance during anxiety. In parallel, HR decelerated to both threat contexts indicating fear bradycardia to these threatening contexts as compared to the safe context. These results support the idea of hypervigilance in anxiety-like situations reflected in a long-lasting facilitated processing of sensory information, in contrast to increased selective attention to specific imminent threat during fear. Thus, this study further supports the defense-cascade model with vigilance and orienting in the post-encounter phase of threat (anxiety), while selective attention and defensive mobilization in the circa-strike phase of threat (fear).