Brain dynamics of visual attention during anticipation and encoding of threat- and safe-cues in spider-phobic individuals

Electrophysiological Correlates of Amplified Emotion-Related Cognitive Processing Evoked by Self-Administered Disgust Images

In the processing of emotions, the brain prepares and reacts in distinctive manners depending upon the negative or positive nuance of the emotion elicitors. Previous investigations showed that negative elicitors generally evoke more intense neural activities than positive and neutral ones, as reflected in the augmented amplitude of all sub-components of the event-related potentials (ERP) late posterior positivity (LPP) complex, while less is known about the emotion of disgust. The present study aimed to examine whether the LPP complex during the processing of disgust stimuli showed greater amplitude than other emotion elicitors with negative or positive valences, thus confirming it as a neural marker of disgust-related negativity bias at earlier or later stages. Thus, in the present study, we leveraged the ERP technique during the execution of an affective self-administered visual stimuli task to disentangle the neural contributions associated with images of positive, negative, disgust, or neutral emotions. Crucially, we showed that handling with disgust elicitors prompted the greatest neural activity and the highest delay during self-administration. Overall, we demonstrated progressive neural activities associated with the unpleasantness of the emotion elicitors and peculiar processing for disgust compared with all other emotions.

The overgeneralization of pain-related fear in individuals with higher pain sensitivity: A behavioral and event-related potential study

Fear generalization contributes to the development and maintenance of pain. Pain sensitivity has been proposed to predict the strength of fear responses to aversive stimuli. However, whether individual variation in pain sensitivity affects pain-related fear generalization and its underlying cognitive processing remains unclear. To address this gap, we recorded behavioral and event-related potential (ERP) data among 22 high pain sensitivity (HPS) and 22 low pain sensitivity (LPS) healthy adults when exposed to a fear generalization paradigm. The behavioral results indicate that the HPS group displayed higher unconditioned stimulus expectancy and greater fear, arousal, and anxiety ratings to conditioned stimulus and generalization stimulus than the LPS group (all p values < 0.05). The ERP results showed that the HPS group exhibited a larger late positive potential evoked by GS2, GS3 and CS- (all p < 0.005) but a smaller N1 evoked by all CS and GSs (all p values < 0.05) relative to the LPS group. These findings suggest that individuals with a high level of pain sensitivity allocate more attention resources to pain-related threatening stimuli, which contributes to an overgeneralization of pain-related fear.

Transdiagnostic Fear and Anxiety: Prospective Prediction Using the No-Threat, Predictable Threat, and Unpredictable Threat Task

Background

Fear and anxiety are distinct dimensions of psychopathology that may be characterized by differences in dimensional threat reactivity. Heightened response to predictable threat is hypothesized to underlie fear symptomatology, whereas increased response to unpredictable threat may underlie anxiety. Despite widespread acceptance of this model, these purported associations have rarely been tested, and the prognostic value of predictable and unpredictable threat responding is unclear. Here we examined multilevel indicators of predictable and unpredictable threat response as cross-sectional correlates and prospective predictors of transdiagnostic fear and anxiety.

Methods

Fifty-two individuals with varying levels of internalizing psychopathology (31 female) performed the no-threat, predictable threat, and unpredictable threat task. Transdiagnostic fear and anxiety were assessed at baseline (time 1) and approximately 1.5 years later (time 2). We used event-related potential, the stimulus-preceding negativity, as a measure of threat anticipation and startle eyeblink as a measure of defensive reactivity during the no-threat, predictable threat, and unpredictable threat task. These probes were assessed as cross-sectional correlates and prospective predictors of fear and anxiety.

Results

Participants with larger time 1 stimulus-preceding negativities to predictable threat were characterized by greater time 1 fear. Larger time 1 stimulus-preceding negativities to unpredictable threat were associated with greater increases in time 2 anxiety. Heightened time 1 startle to predictable threat predicted larger increases in time 2 fear.

Conclusions

Results validate predictable and unpredictable threat responding as dimensional correlates of transdiagnostic fear versus anxiety and suggest that psychophysiological measures of predictable and unpredictable threat response hold promise as prospective predictors of trajectories of fear and anxiety.

Improved attention and performance monitoring in high procrastinating students after positive relative to negative norm-referenced feedback

Procrastination is an irrational delay of task completion. Previous studies have demonstrated that individuals who often procrastinate present deficits in attentional control and performance monitoring and that these dysfunctions might be differentially manifested depending on the motivational context. Building upon these results, the present event-related potential (ERP) study aimed to investigate the impact of norm-referenced feedback on executive functions among students with high (HP; N = 75) or low (LP; N = 77) procrastination levels. Participants completed the parametric Go/No-Go task, while receiving either positive or negative false feedback indicating how well they performed in comparison to others. The results indicated that positive (as opposed to negative) feedback led to higher self-reported arousal and increased post-error slowing in HP (vs. LP) participants. Moreover, neurophysiological measures indicated lower neural activation linked to attentional control (P300) and performance monitoring (ERN, CRN and Pe) in HP than LP participants, while the groups did not differ in these indices during the positive feedback condition. Obtained findings indicate that HP might be more sensitive to the motivating effects of success and more vulnerable to the detrimental influence of failure.

Understanding anxiety symptoms as aberrant defensive responding along the threat imminence continuum

Threat-anticipatory defensive responses have evolved to promote survival in a dynamic world. While inherently adaptive, aberrant expression of defensive responses to potential threat could manifest as pathological anxiety, which is prevalent, impairing, and associated with adverse outcomes. Extensive translational neuroscience research indicates that normative defensive responses are organized by threat imminence, such that distinct response patterns are observed in each phase of threat encounter and orchestrated by partially conserved neural circuitry. Anxiety symptoms, such as excessive and pervasive worry, physiological arousal, and avoidance behavior, may reflect aberrant expression of otherwise normative defensive responses, and therefore follow the same imminence-based organization. Here, empirical evidence linking aberrant expression of specific, imminence-dependent defensive responding to distinct anxiety symptoms is reviewed, and plausible contributing neural circuitry is highlighted. Drawing from translational and clinical research, the proposed framework informs our understanding of pathological anxiety by grounding anxiety symptoms in conserved psychobiological mechanisms. Potential implications for research and treatment are discussed.

The priming effects of emotional vocal expressions on face encoding and recognition: An ERP study

Previous studies have suggested that emotional primes, presented as visual stimuli, influence face memory (e.g., encoding and recognition). However, due to stimulus-associated issues, whether emotional primes affect face encoding when the priming stimuli are presented in an auditory modality remains controversial. Moreover, no studies have investigated whether the effects of emotional auditory primes are maintained in later stages of face memory, such as face recognition. To address these issues, participants in the present study were asked to memorize angry and neutral faces. The faces were presented after a simple nonlinguistic interjection expressed with angry or neutral prosodies. Subsequently, participants completed an old/new recognition task in which only faces were presented. Event-related potential (ERP) results showed that during the encoding phase, all faces preceded by an angry vocal expression elicited larger N170 responses than faces preceded by a neutral vocal expression. Angry vocal expression also enhanced the late positive potential (LPP) responses specifically to angry faces. In the subsequent recognition phase, preceding angry vocal primes reduced early LPP responses to both angry and neutral faces and late LPP responses specifically to neutral faces. These findings suggest that the negative emotion of auditory primes influenced face encoding and recognition.

The role of selective attention in the positivity offset: Evidence from event related potentials

Some research suggests that positive and negative valence stimuli may be processed differently. For example, negative material may capture and hold attention more readily than equally arousing positive material. This is called the negativity bias, and it has been observed as both behavioural and electroencephalographic (EEG) effects. Consequently, it has been attributed to both automatic and elaborative processes. However, at the lowest levels of arousal, faster reaction times and stronger EEG responses to positive material have been observed. This is called the positivity offset, and the underlying cognitive mechanism is less understood. To study the role of selective attention in the positivity offset, participants completed a negative affective priming (NAP) task modified to dissociate priming for positive and negative words. The task required participants to indicate the valence of a target word, while simultaneously ignoring a distractor. In experiment 1, a behavioural facilitation effect (faster response time) was observed for positive words, in stark contrast to the original NAP task. These results were congruent with a previously reported general categorization advantage for positive material. In experiment 2, participants performed the task while EEG was recorded. In additional to replicating the behavioural results from experiment 1, positive words elicited a larger Late Positive Potential (LPP) component on ignored repetition relative to control trials. Surprisingly, negative words elicited a larger LPP than positive words on control trials. These results suggest that the positivity offset may reflect a greater sensitivity to priming effects due to a more flexible attentional set.

Perceptual processing of stimuli related to an analogue traumatic event: An ERP study

Previous research has suggested that exposure to potentially traumatic events can lead to increased perceptual processing specific to trauma-related stimuli. Moreover, conceptual processing strategies during encoding may reduce the effect of trauma exposure on perceptual processing. The current study investigated the effect of a trauma film on perceptual processing with visual evoked potentials. Participants were primed with perceptual or conceptual processing strategies, then viewed a trauma film and a control film. Participants then looked at emotionally negative and neutral images that were related or unrelated to the films. The amplitude of the P1 evoked potential was measured during image presentation. P1 amplitude was more positive specifically for negative film-related stimuli. Moreover, this effect was stronger in participants primed with perceptual processing. These results suggest that potentially traumatic events increase perceptual processing specifically for trauma-related stimuli, and that conceptual encoding strategies attenuate the effect of exposure to potentially traumatic events on perception.

Contextual Cueing Accelerated and Enhanced by Monetary Reward: Evidence From Event-Related Brain Potentials

The vital role of reward in guiding visual attention has been supported by previous literatures. Here, we examined the motivational impact of monetary reward feedback stimuli on visual attention selection using an event-related potential (ERP) component called stimulus-preceding negativity (SPN) and a standard contextual cueing (CC) paradigm. It has been proposed that SPN reflects affective and motivational processing. We focused on whether incidentally learned context knowledge could be affected by reward. Both behavior and brain data demonstrated that contexts followed by reward feedback not only gave rise to faster implicit learning but also obtained a larger CC effect.

Neuronal correlates of spider phobia in a combined fNIRS-EEG study

Specific phobia is associated with aberrant brain activation in confrontation paradigms with phobic stimuli. In previous EEG research enhanced event-related potentials (ERPs) in the late-positive potential (LPP) window have been observed. Further, studies with functional near-infrared spectroscopy (fNIRS) and fMRI suggest that spider phobia is associated with enhanced activation within cortical and subcortical areas. In the current study we investigated the neuronal correlates of spider phobia in a combined fNIRS-EEG study. To this end, 37 spider phobic patients (PP) and 32 healthy controls (HC) underwent a symptom provocation paradigm during which subjects watched video clips of spiders and domestic animals (confrontation phase) after being primed on the content of the video (anticipation phase). Simultaneously, fNIRS, EEG, electromyography (EMG), electrocardiography and behavioral measures were assessed. Results showed increased LPP amplitudes, increased hemodynamic responses in the cognitive control network, and increased EMG activity and heart rate during spider conditions in PP in comparison to HC. Furthermore, in behavioral ratings PP showed higher emotional distress and avoidance. Behavioral ratings, fNIRS and EEG data showed positive correlations on a between-subject as well as on a within-subject level. Our results merge the existing data on neurophysiological correlates of phobic stimulus processing in hemodynamic and electrophysiological research and extend those of static visual material (pictures) to dynamic visual material (videos).

Level of uncertainty about the affective nature of a pictorial stimulus influences anticipatory neural processes: An event-related potential (ERP) study

Uncertainty about the emotional impact of future events is a common part of everyday life. However, relatively little is known about whether the level of uncertainty about the affective nature of an upcoming visual image influences anticipatory neurocognitive processes. To investigate this, participants viewed a series of negative and neutral pictures, which were preceded by abstract anticipatory cues. Neural activity was measured using event-related potentials (ERPs). In the 'uncertain' cue condition, the cue could be followed by either a negative or a neutral picture with equal probability; in the 'fairly uncertain' condition the cue was followed by a negative picture on 70% of trials, and by a neutral picture on 30% of trials. In the 'certain' condition, the cue was always followed by a negative picture. For the P200 component, reflecting early stages of selective attention, there was no amplitude difference between cue conditions. At later stages of processing, the early posterior negativity (EPN) amplitude was enhanced for cues indicating a greater level of certainty, and the late positive potential (LPP) amplitude was greater for certain, compared to fairly uncertain and uncertain cues. The stimulus preceding negativity (SPN), an index of anticipatory processing, was more negative for certain cues compared to fairly uncertain and uncertain cues. For the SPN there was no difference between fairly uncertain and uncertain cues. These results provide evidence that the level of uncertainty regarding the affective nature of an upcoming picture influenced several stages of processing during the anticipation of the stimulus.

Keep calm and carry on: electrophysiological evaluation of emotional anticipation in the second language

Investigations of the so-called ‘foreign language effect’ have shown that emotional experience is language-dependent in bilingual individuals. Response to negative experiences, in particular, appears attenuated in the second language (L2). However, the human brain is not only reactive, but it also builds on past experiences to anticipate future events. Here, we investigated affective anticipation in immersed Polish–English bilinguals using a priming paradigm in which a verbal cue of controlled affective valence allowed making predictions about a subsequent picture target. As expected, native word cues with a negative valence increased the amplitude of the stimulus preceding negativity, an electrophysiological marker of affective anticipation, as compared with neutral ones. This effect was observed in Polish–English bilinguals and English monolinguals alike. The contrast was non-significant when Polish participants were tested in English, suggesting a possible reduction in affective sensitivity in L2. However, this reduction was not validated by a critical language × valence interaction in the bilingual group, possibly because they were highly fluent in English and because the affective stimuli used in the present study were particularly mild. These results, which are neither fully consistent nor inconsistent with the foreign language effect, provide initial insights into the electrophysiology of affective anticipation in bilingualism.

Neuropsychiatric Disorders as Erratic Attention Regulation - Lessons from Electrophysiology

Attention related electrophysiological waves, such as P300, often deviate from norm in various populations of neuropsychiatric patients. For example, the amplitude is often smaller and the latency is often longer in major depressive disorder, in bipolar disorder and in schizophrenia. On the other hand, in other neuropsychiatric populations, it is often possible to note the opposite phenomena of larger P300 amplitude and shorter latency in comparison with norm, but only for a specific subset of stimuli. This is often reported in various anxiety disorders, substance abuse and various chronic pain syndromes. These findings in the various clinical populations, on their commonalities and differences, are presented in this work. The prevalence of these two types of deviations in the electrophysiological markers of attention, shared by multiple neuropsychiatric populations, raise interesting questions regarding the role of attention deviation and regulation in neuropsychiatry. We present these questions and outline a possible hypothesis in this regard. Furthermore, such potential sensitivity of the attention-related markers to clinical dynamics suggests they could be candidates for monitoring and, potentially, early-sensing of clinical dynamics. Therefore, we discuss the potential usability of such markers.

Impaired early visual categorization of fear in social anxiety

Social anxiety is associated with biased social perception, especially of ambiguous cues. While aberrations in high-level processes (e.g., cognitive appraisal and interpretation) have been implicated in such biases, contributions of early, low-level stimulus processing remain unclear. Categorical perception represents an efficient process to resolve signal ambiguity, and categorical emotion perception can swiftly classify sensory input, "tagging" biologically important stimuli at early stages of processing to facilitate ecological response. However, early threat categorization could be disrupted by exaggerated (or disinhibited) threat processing in anxiety, resulting in biased perception of ambiguous signals. We tested this hypothesis among individuals with low and high trait social anxiety (LSA/HSA; defined relative to the current sample), who performed a two-alternative forced-choice (fear or neutral) task on facial expressions parametrically varied along a neutral-fear continuum. The groups diverged in the reaction time (RT) profile along the neutral-fear continuum, which was characteristic of categorical perception in the LSA (vs. HSA) group with drastically increased RT from neutral to intermediate (boundary) fear intensities, contrasting monotonic, nonsignificant RT changes in the HSA group. Neurometric analysis along the continuum identified an early neutral-fear categorization operation (arising in the P1, an early visual ERP at 100 ms), which was nonetheless impaired in the HSA group (due to disinhibited response at the neutral-fear boundary). Absent group differences in higher-level cognitive operations (identified by later ERPs), current findings highlight a dispositional cognitive vulnerability in early visual categorization of social threat, which could precipitate further cognitive aberrations and, eventually, the onset of social anxiety disorder.

Extinction-resistant attention to long-term conditioned threat is indexed by selective visuocortical alpha suppression in humans

Previous electrophysiological studies in humans have shown rapid modulations of visual attention after conditioned threat vs. safety cues (<500 ms post-stimulus), but it is unknown whether this attentional prioritization is sustained throughout later time windows and whether it is robust to extinction. To investigate sustained visual attention, we assessed visuocortical alpha suppression in response to conditioned and extinguished threat. We reanalysed data from N = 87 male participants that had shown successful long-term threat conditioning and extinction in self reports and physiological measures in a two-day conditioning paradigm. The current EEG time-frequency analyses on recall test data on Day 2 revealed that previously threat-conditioned vs. safety cues evoked stronger occipital alpha power suppression from 600 to 1200 ms. Notably, this suppression was resistant to previous extinction. The present study showed for the first time that threat conditioning enhances sustained modulation of visuocortical attention to threat in the long term. Long-term stability and extinction resistance of alpha suppression suggest a crucial role of visuocortical attention mechanisms in the maintenance of learned fears.

Negative expectations influence behavioral and ERP responses in the subsequent recognition of expectancy-incongruent neutral events

Previous studies have shown that expectancy incongruence in emotional stimuli influences the encoding (i.e., the first stage of memory processing) of the stimuli. However, it is unknown about whether expectancy incongruence influences later stages of memory processing, such as recognition. To this end, expectancy cues were presented prior to emotional pictures. Most often, the cues accurately indicated the emotional consequences of the pictures, but in some cases the consequence was incongruent with the expectations, and a picture from another emotional category was presented. Afterward, participants completed an unexpected recognition task in which old and novel pictures were not preceded by expectancy cues. The results showed that, in the encoding phase, expectancy incongruence reduced response accuracy when categorizing pictorial emotions, and the effect was smaller for neutral pictures than for negative pictures. ERP results showed stronger and weaker responses to expectancy incongruent pictures compared to congruent pictures in time ranges related to the encoding-related early and middle late positive potential (LPP), respectively. In the subsequent recognition phase, d' scores were higher for incongruent neutral pictures than for congruent ones. Expectancy incongruence enlarged the P2 response but reduced the recognition-related early LPP response for neutral pictures. However, effects of expectancy incongruence were not seen for negative pictures. Therefore, the findings in the present study indicate that negative expectations influence the later recognition of expectancy incongruent neutral events, whereas negative events are more resistant to the effects of expectation incongruence.

Expectation Gates Neural Facilitation of Emotional Words in Early Visual Areas

The current study examined whether emotional expectations gate attention to emotional words in early visual cortex. Color cues informed about word valence and onset latency. We observed a stimulus-preceding negativity prior to the onset of cued words that was larger for negative than for neutral words. This indicates that in anticipation of emotional words more attention was allocated to them than to neutral words before target onset. During stimulus presentation the steady-state visual evoked potential (SSVEP), elicited by flickering words, was attenuated for cued compared to uncued words, indicating sharpened sensory activity, i.e., expectation suppression. Most importantly, the SSVEP was more enhanced for negative than neutral words when these were cued. Uncued conditions did not differ in SSVEP amplitudes, paralleling previous studies reporting lexico-semantic but not early visual effects of emotional words. We suggest that cueing mediates re-entrant engagement of visual resources by providing an early “affective gist” of an upcoming word. Consequently, visual single-word studies may have underestimated attentional effects of emotional words and their anticipation during reading.

Contextual effects of angry vocal expressions on the encoding and recognition of emotional faces: An event-related potential (ERP) study

It has been shown that stimulus memory (e.g., encoding and recognition) is influenced by emotion. In terms of face memory, event-related potential (ERP) studies have shown that the encoding of emotional faces is influenced by the emotion of concomitant context, when contextual stimuli were input from a visual modality. Behavioral studies also investigated the effect of contextual emotion on subsequent recognition of neutral faces. However, there might be no studies ever investigating the context effect on face encoding and recognition, when contextual stimuli were input from other sensory modalities (e.g., an auditory modality). Additionally, it may be unknown about the neural mechanisms underlying context effects on recognition of emotional faces. Therefore, the present study aimed to use vocal expressions as contexts to investigate whether contextual emotion influences ERP responses during face encoding and recognition. To this end, participants in the present study were asked to memorize angry and neutral faces. The faces were presented concomitant with either angry or neutral vocal expressions. Subsequently, participants were asked to perform an old/new recognition task, in which only faces were presented. In the encoding phase, ERP results showed that compared to neutral vocal expression, angry vocal expressions led to smaller P1 and N170 responses to both angry and neutral faces. For angry faces, however, late positive potential (LPP) responses were increased in the angry voice condition. In the later recognition phase, N170 responses were larger for neutral-encoded faces that had been presented with angry compared to neutral vocal expressions. Preceding angry vocal expression increased FN400 and LPP responses to both neutral-encoded and angry-encoded faces, when the faces showed the encoded expression. Therefore, the present study indicates that contextual emotion with regard to vocal expression influences neural responses during face encoding and subsequent recognition.

Emotion in Context: How Sender Predictability and Identity Affect Processing of Words as Imminent Personality Feedback

Recent findings suggest that communicative context affects the timing and magnitude of emotion effects in word processing. In particular, social attributions seem to be one important source of plasticity for the processing of affectively charged language. Here, we investigate the timing and magnitude of ERP responses toward positive, neutral, and negative trait adjectives during the anticipation of putative socio-evaluative feedback from different senders (human and computer) varying in predictability. In the first experiment, during word presentation participants could not anticipate whether a human or a randomly acting computer sender was about to give feedback. Here, a main effect of emotion was observed only on the late positive potential (LPP), showing larger amplitudes for positive compared to neutral adjectives. In the second study the same stimuli and set-up were used, but a block-wise presentation was realized, resulting in fixed and fully predictable sender identity. Feedback was supposedly given by an expert (psychotherapist), a layperson (unknown human), and again by a randomly acting computer. Main effects of emotion started with an increased P1 for negative adjectives, followed by effects at the N1 and early posterior negativity (EPN), showing both largest amplitudes for positive words, as well as for the LPP, where positive and negative words elicited larger amplitudes than neutral words. An interaction revealed that emotional LPP modulations occurred only for a human sender. Finally, regardless of content, anticipating human feedback led to larger P1 and P3 components, being highest for the putative expert. These findings demonstrate the malleability of emotional language processing by social contexts. When clear predictions can be made, our brains rapidly differentiate between emotional and neutral information, as well as between different senders. Attributed human presence affects emotional language processing already during feedback anticipation, in line with a selective gating of attentional resources via anticipatory social significance attributions. By contrast, emotion effects occur much later, when crucial social context information is still missing. These findings demonstrate the context-dependence of emotion effects in word processing and are particularly relevant since virtual communication with unknown senders, whose identity is inferred rather than perceived, has become reality for millions of people.

Amygdala reactivity and connectivity during social and non-social aversive stimulation in social anxiety disorder

Social anxiety disorder (SAD) is characterized by exaggerated amygdala reactivity in response to symptom provocation, but it is unclear if such hyper-reactivity is elicited by disorder-specific challenges only or characterizes reactions to aversive stimuli in general. Here, using functional magnetic resonance imaging in 14 patients with SAD, as compared to 12 healthy controls, we found that amygdala hyper-reactivity is confined to disorder-relevant social stimulation. SAD patients displayed increased amygdala reactivity to fearful as compared to neutral facial pictures, but not in response to generally aversive but mainly non-social stimulation when compared to neutral pictorial stimuli taken from the International Affective Picture System. The increased amygdala reactivity was not mediated by an altered prefrontal inhibition among SAD patients as compared to controls, suggesting increased bottom-up processes rather than attenuated top-down control. In conclusion, the enhanced amygdala reactivity in SAD seems specific to socially relevant stimuli rather than aversive stimuli in general.

Seeing is believing: Early perceptual brain processes are modified by social feedback

Over 6 decades ago, experimental evidence from social psychology revealed that individuals could alter their responses in perceptual judgement tasks if they differed from the prevailing view emitted by a group of peers. Responses were thus modulated to agree with the opinion of the social group. An open question remains whether such changes actually reflect modified perception, or whether they are simply the result of a feigned agreement, indicating submissive acceptance. In this study, we addressed this topic by performing a perceptual task involving the assessment of ambiguous and distinct stimuli. Participants were asked to judge the colours of squares, before, and after receiving feedback for their response. In order to pinpoint the moment in time that social feedback affected neural processing, ERP components to ambiguous stimuli were compared before and after participants received supposed social feedback that agreed with, or disputed their response. The comparison revealed the presence of differences beginning already 100ms after stimulus presentation (on the P1 and N1 components) despite otherwise identical stimuli. The modulation of these early components, normally thought to be dependent on low-level visual features, demonstrate that social pressure tangibly modifies early perceptual brain processes.

Event-related potentials to threat of predictable and unpredictable shock

Cognitive affective neuroscience tasks that are straightforward to administer, measure key constructs of interest, and can be used in different lab settings and with multiple psychophysiological methods can lead to a more complete understanding of experimental effects. The no-threat, predictable threat, unpredictable threat (NPU-threat) task assesses constructs of interest to both clinical and basic affective science literatures, is relatively brief to administer, and has been used across labs with a number of different measurements (e.g., startle eyeblink, fMRI, corrugator response, subjective ratings). ERPs provide another means of assessing neurobiological reactivity during the NPU-threat task, but to date such measures have been underutilized. That is, no study has yet evaluated cue-elicited ERPs in the NPU-threat task. Here, cue-elicited ERPs were assessed in 78 participants who completed a version of the NPU-threat task previously shown to reliably moderate startle eyeblink amplitudes. Results showed larger P2 amplitudes for unpredictable versus predictable trials, increased P3s and late positive potentials for threatening versus no-threat trials, as well as larger stimulus preceding negativities for threatening versus no-threat trials (driven primarily by predictable threat cues). In line with prior work, we observed enhanced startle eyeblink for threatening versus no-threat trials and for unpredictable compared to predictable threat interstimulus intervals. In addition, the probe-elicited P3 was suppressed for predictable and unpredictable compared to no-threat trials. Therefore, cue-elicited ERPs, which can be recorded alongside other measures in the NPU-threat task (e.g., startle), may provide useful indices of temporally distinct stages of predictable and unpredictable threat processing.

Fear of pain and event-related potentials during exposure to image-cued somatosensory stimulation

Numerous behavior studies have assessed links of pain-related fear with biases in attention towards pain stimuli but considerably less is known about neural processes underlying such biases. To address this gap, event-related potentials (ERPs) were examined as 39 high pain-fearful (Hi-FOP) and 36 low pain-fearful (Lo-FOP) adults (1) viewed non-painful versus painful images and (2) subsequently received non-painful versus possibly painful somatosensory stimulation, respectively. The Hi-FOP group judged both non-painful and painful somatosensory stimulation to be more intense than Lo-FOP group members did. Hi-FOP group members also displayed smaller N1 amplitudes than Lo-FOP group members did during image presentations, regardless of image type. Finally, Lo-FOP group members exhibited larger P3 amplitudes when processing potentially painful somatosensory stimulation compared to non-painful stimulation while no such difference was observed in Hi-FOP group members. Overall results suggested that the pain-fearful tended to exaggerate the subjective intensity of potentially painful somatosensory stimuli but allocated comparatively fewer cognitive resources to processing such stimulation; arguably, this pattern perpetuates high fear of pain levels.

Neural response patterns in spider, blood-injection-injury and social fearful individuals: new insights from a simultaneous EEG/ECG-fMRI study

In the present simultaneous EEG/ECG-fMRI study we compared the temporal and spatial characteristics of the brain responses and the cardiac activity during fear picture processing between spider, blood-injection-injury (BII) and social fearful as well as healthy (non-fearful) volunteers. All participants were presented with two neutral and six fear-related blocks of pictures: two social, two spider and two blood/injection fear blocks. In a social fear block neutral images were occasionally interspersed with photographs of angry faces and social exposure scenes. In spider and blood/injection fear blocks neutral pictures were interspersed with spider fear-relevant and blood/injection pictures, respectively. When compared to healthy controls the social fear group responded with increased activations in the anterior orbital, middle/anterior cingulate and middle/superior temporal areas for pictures depicting angry faces and with a few elevated superior frontal activations for social exposure scenes. In the blood/injection fear group, heart rate was decreased and the activity in the middle/inferior frontal and visual processing regions was increased for blood/injection pictures. The HR decrease for blood/injection pictures correlated with increased frontal responses. In the spider fear group, spider fear-relevant pictures triggered increased activations within a broad subcortical and cortical neural fear network. The HR response for spider fear-relevant stimuli was increased and correlated with an increased insula and hippocampus activity. When compared to healthy controls, all fear groups showed higher LPP amplitudes for their feared cues and an overall greater P1 hypervigilance effect. Contrasts against the fear control groups showed that the increased responses for fear-specific stimuli are mostly related to specific fears and not to general anxiety proneness. The results suggest different engagement of cognitive evaluation and down-regulation strategies and an overall increased sensitization of the fear system in the three fear groups.

The Set of Fear Inducing Pictures (SFIP): Development and validation in fearful and nonfearful individuals

Emotionally charged pictorial materials are frequently used in phobia research, but no existing standardized picture database is dedicated to the study of different phobias. The present work describes the results of two independent studies through which we sought to develop and validate this type of database—a Set of Fear Inducing Pictures (SFIP). In Study 1, 270 fear-relevant and 130 neutral stimuli were rated for fear, arousal, and valence by four groups of participants; small-animal (N = 34), blood/injection (N = 26), social-fearful (N = 35), and nonfearful participants (N = 22). The results from Study 1 were employed to develop the final version of the SFIP, which includes fear-relevant images of social exposure (N = 40), blood/injection (N = 80), spiders/bugs (N = 80), and angry faces (N = 30), as well as 726 neutral photographs. In Study 2, we aimed to validate the SFIP in a sample of spider, blood/injection, social-fearful, and control individuals (N = 66). The fear-relevant images were rated as being more unpleasant and led to greater fear and arousal in fearful than in nonfearful individuals. The fear images differentiated between the three fear groups in the expected directions. Overall, the present findings provide evidence for the high validity of the SFIP and confirm that the set may be successfully used in phobia research.

Cue reactivity towards bodies in anorexia nervosa - common and differential effects in adolescents and adults

BACKGROUND

Aberrant reward mechanisms with regard to slim body shapes are discussed in patients with anorexia nervosa (AN). The aim of the present study was to examine of cue reactivity toward body shapes in AN via the late positive potential (LPP), an event-related electroencephalography (EEG) component. By including adolescents and adults, aspects of development and chronification could be studied (2 × 2 design).

METHODS

Thirty-two female AN patients (19 adolescents and 13 adults) and 37 control participants (16 adolescents and 21 adults) were included. Standardized photographic stimuli showing women's bodies in underwear from five body mass index (BMI) categories (extremely underweight to extremely overweight) were presented. During picture evaluation, EEG activity was recorded (10-20 system). The LPP was measured in two time windows characterized by different topographies (450-700 ms: posterior; 1000-1300 ms: central).

RESULTS

Regarding the posterior component, LPP amplitudes were clearly reduced in adult but not in adolescent patients; for both time windows the LPP showed differential patterns over BMI categories for patients and controls. Regarding the central component, a highly significant linear decrease from extremely underweight to extremely overweight body shapes was revealed in patients and no significant modulation in control participants.

CONCLUSIONS

Adolescent and adult patients show increased sustained attention toward extremely underweight bodies. In chronically ill patients, this bias appears to be accompanied by generally reduced automatic attention. The LPP findings provide a differentiated picture of aberrant cue reactivity which could be interpreted as motivated attention toward body shapes in AN.

Event-related potential components as measures of aversive conditioning in humans

For more than 60 years, the gold standard for assessing aversive conditioning in humans has been the skin conductance response (SCR), which arises from the activation of the peripheral nervous system. Although the SCR has been proven useful, it has some properties that impact the kinds of questions it can be used to answer. In particular, the SCR is slow, reaching a peak 4-5 s after stimulus onset, and it decreases in amplitude after a few trials (habituation). The present study asked whether the late positive potential (LPP) of the ERP waveform could be a useful complementary method for assessing aversive conditioning in humans. The SCR and LPP were measured in an aversive conditioning paradigm consisting of three blocks in which one color was paired with a loud noise (CS+) and other colors were not paired with the noise (CS-). Participants also reported the perceived likelihood of being exposed to the noise for each color. Both SCR and LPP were significantly larger on CS+ trials than on CS- trials. However, SCR decreased steeply after the first conditioning block, whereas LPP and self-reports were stable over blocks. These results indicate that the LPP can be used to assess aversive conditioning and has several useful properties: (a) it is a direct response of the central nervous system, (b) it is fast, with an onset latency of 300 ms, (c) it does not habituate over time.

Contextual effects of surprised expressions on the encoding and recognition of emotional target faces: An event-related potential (ERP) study

Several studies reported that the encoding and recognition of emotional target faces are modulated by negative contextual expressions. However, it is unknown whether other contextual expressions, such as emotionally ambiguous expressions, affect the encoding and recognition of target faces. To this end, electroencephalography (EEG) was recorded during the presentation of angry or happy target faces after a random sequence of surprised or neutral contextual faces that did not differ in normative valence ratings. Subsequently, participants were asked to perform an unexpected old/new recognition task in which target faces were shown in either the encoded or a non-encoded expression. During the encoding phase, event-related potential (ERP) results showed that surprised as compared to neutral contextual faces led to smaller late positive potentials (LPP) for happy but not for angry target faces. Similar effects were also observed in the N170, even though the interaction of context and target expression failed to reach statistical significance. In the later recognition phase, recognition rates were lower for encoded happy faces when they had been encountered in surprised as compared to neutral context, regardless of whether the target face showed the encoded or a non-encoded expression. However, this context effect was not observed for angry-encoded faces. Taken together, the present study indicates that ambiguous contextual expressions, e.g., surprised faces, affect structural and cognitive encoding and later recognition of happy target faces to a larger extent than neutral contextual faces; whereas angry faces are more resistant to context effects.

Active avoidance and attentive freezing in the face of approaching threat

Defensive behaviors in animals and humans vary dynamically with increasing proximity of a threat and depending upon the behavioral repertoire at hand. The current study investigated physiological and behavioral adjustments and associated brain activation when participants were exposed to dynamically approaching threat that was either inevitable or could be avoided by motor action. When the approaching threat was inevitable, attentive freezing was observed as indicated by fear bradycardia, startle potentiation, and a dynamic increase in activation of the anterior insula and the periaqueductal grey. In preparation for active avoidance a switch in defensive behavior was observed characterized by startle inhibition and heart rate acceleration along with potentiated activation of the amygdala and the periaqueductal grey. Importantly, the modulation of defensive behavior according to threat imminence and the behavioral option at hand was associated with activity changes in the ventromedial prefrontal cortex. These findings improve our understanding of brain mechanisms guiding human behavior during approaching threat depending on available resources.

Glucocorticoid Administration Improves Aberrant Fear-Processing Networks in Spider Phobia

Glucocorticoids reduce phobic fear in patients with anxiety disorders. Previous studies have shown that fear-related activation of the amygdala can be mediated through the visual cortical pathway, which includes the fusiform gyrus, or through other pathways. However, it is not clear which of the pathways that activate the amygdala is responsible for the pathophysiology of a specific phobia and how glucocorticoid treatment alleviates fear processing in these neural networks. We recorded the brain activity with functional magnetic resonance imaging in patients with spider phobia, who received either 20 mg of cortisol or a placebo while viewing pictures of spiders. We also tested healthy participants who did not receive any medication during the same task. We performed dynamic causal modelling (DCM), a connectivity analysis, to examine the effects of cortisol on the networks involved in processing fear and to examine if there was an association between these networks and the symptoms of the phobia. Cortisol administration suppressed the phobic stimuli-related amygdala activity to levels comparable to the healthy participants and reduced subjective phobic fear. The DCM analysis revealed that cortisol administration suppressed the aberrant inputs into the amygdala that did not originate from the visual cortical pathway, but rather from a fast subcortical pathway mediated by the pulvinar nucleus, and suppressed the interactions between the amygdala and fusiform gyrus. This network changes were distinguishable from healthy participants and considered the residual changes under cortisol administration. We also found that the strengths of the aberrant inputs into the amygdala were positively correlated with the severity of spider phobia. This study demonstrates that patients with spider phobia show an aberrant functional connectivity of the amygdala when they are exposed to phobia-related stimuli and that cortisol administration can alleviate this fear-specific neural connectivity.

Better Not to Know? Emotion Regulation Fails to Benefit from Affective Cueing

Often we know whether an upcoming event is going to be good or bad. But does that knowledge help us regulate ensuing emotions? To address this question, we exposed participants to alleged social feedback that was either positive or negative. On half the trials, a preceding cue indicated the feedback’s affective quality. On the remaining trials, the cue was uninformative. In two different blocks, participants either appraised feedback spontaneously or down-regulated ensuing emotions using a controlled appraisal strategy. Event-related potentials (ERPs) recorded throughout both blocks revealed an increased late positive potential (LPP) during cue and feedback epochs when cues were affectively informative as compared to uninformative. Additionally, during feedback epochs only, informative, but not uninformative, cueing was associated with an appraisal effect whereby controlled appraisal reduced the LPP relative to spontaneous appraisal for negative feedback. There was an opposite trend for positive feedback. Together, these results suggest that informative cues allowed individuals to anticipate an emotional response and to adjust emotion regulation. Overall, however, informative cues seemed to have prolonged and intensified emotional responding when compared with uninformative cues. Thus, affective cueing appears to be contraindicated when individuals aim to reduce their emotions.

Prepare for scare-Impact of threat predictability on affective visual processing in spider phobia

The visual processing of emotional faces is influenced by individual's level of stress and anxiety. Valence unspecific affective processing is expected to be influenced by predictability of threat. Using a design of phasic fear (predictable threat), sustained anxiety (unpredictable threat) and safety (no threat), we investigated the magnetoencephalographic correlates and temporal dynamics of emotional face processing in a sample of phobic patients. Compared to non-anxious controls, phobic individuals revealed decreased parietal emotional attention processes during affective processing at mid-latency and late processing stages. While control subjects showed increasing parietal processing of the facial stimuli in line with decreasing threat predictability, phobic subjects revealed the opposite pattern. Decreasing threat predictability also led to increasing neural activity in the orbitofrontal and dorsolateral prefrontal cortex at mid-latency stages. Additionally, unpredictability of threat lead to higher subjective discomfort compared to predictability of threat and no threat safety condition. Our findings indicate that visual processing of emotional information is influenced by both stress induction and pathologic anxiety.

Attentional Bias in Patients with Decompensated Tinnitus: Prima Facie Evidence from Event-Related Potentials

Tinnitus refers to the auditory perception of sound in the absence of external sound or electric stimuli. The influence of tinnitus on cognitive processing is at the cutting edge of ongoing tinnitus research. In this study, we adopted an objective indicator of attentional processing, i.e. the mismatch negativity (MMN), to assess the attentional bias in patients with decompensated tinnitus. Three kinds of pure tones, D1 (8,000 Hz), S (8,500 Hz) and D2 (9,000 Hz), were used to induce event-related potentials (ERPs) in the normal ear. Employing the oddball paradigm, the task was divided into two blocks in which D1 and D2 were set as deviation stimuli, respectively. Only D2 induced a significant MMN in the tinnitus group, while neither D1 nor D2 was able to induce MMN in the control group. In addition, the ERPs in the left hemisphere, which were recorded within the time window of 90-150 ms (ERP 90-150 ms), were significantly higher than those in the right hemisphere in the tinnitus group, while no significant difference was observed in the control group. Lastly, the amplitude of ERP 90-150 ms in the tinnitus group was significantly higher than that in the control group. These findings suggest that patients with decompensated tinnitus showed automatic processing of acoustic stimuli, thereby indicating that these patients allocated more cognitive resources to acoustic stimulus processing. We suggest that the difficulty in disengaging or facilitated attention of patients might underlie this phenomenon. The limitations of the current study are discussed.