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result(s) for
"Wieser, Matthias"
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The effect of trait anxiety on attentional mechanisms in combined context and cue conditioning and extinction learning
by
Stegmann, Yannik
,
Pauli, Paul
,
Reicherts, Philipp
in
631/378/1595/2636
,
631/378/2649/1310
,
Adolescent
2019
Sensory processing and attention allocation are shaped by threat, but the role of trait-anxiety in sensory processing as a function of threat predictability remains incompletely understood. Therefore, we measured steady-state visual evoked potentials (ssVEPs) as an index of sensory processing of predictable and unpredictable threat cues in 29 low (LA) and 29 high (HA) trait-anxious participants during a modified NPU-paradigm followed by an extinction phase. Three different contextual cues indicated safety (N), predictable (P) or unpredictable threat (U), while foreground cues signalled shocks in the P-condition only. All participants allocated increased attentional resources to the central P-threat cue, replicating previous findings. Importantly, LA individuals exhibited larger ssVEP amplitudes to contextual threat (U and P) than to contextual safety cues, while HA individuals did not differentiate among contextual cues in general. Further, HA exhibited higher aversive ratings of all contexts compared to LA. These results suggest that high trait-anxious individuals might be worse at discriminating contextual threat stimuli and accordingly overestimate the probability and aversiveness of unpredictable threat. These findings support the notion of aberrant sensory processing of unpredictable threat in anxiety disorders, as this processing pattern is already evident in individuals at risk of these disorders.
Journal Article
Fearful faces heighten the cortical representation of contextual threat
by
Keil, Andreas
,
Wieser, Matthias J.
in
Adult
,
Arousal - physiology
,
Biological and medical sciences
2014
Perception of facial expressions is typically investigated by presenting isolated face stimuli. In everyday life, however, faces are rarely seen without a surrounding visual context that affects perception and interpretation of the facial expression. Conversely, fearful faces may act as a cue, heightening the sensitivity of the visual system to effectively detect potential threat in the environment. In the present study, we used steady-state visually evoked potentials (ssVEPs) to examine the mutual effects of facial expressions (fearful, neutral, happy) and affective visual context (pleasant, neutral, threat). By assigning two different flicker frequencies (12 vs. 15Hz) to the face and the visual context scene, cortical activity to the concurrent stimuli was separated, which represents a novel approach to independently tracking the cortical processes associated with the face and the context. Twenty healthy students viewed flickering faces overlaid on flickering visual scenes, while performing a simple change-detection task at fixation, and high-density EEG was recorded. Arousing background scenes generally drove larger ssVEP amplitudes than neutral scenes. Importantly, background and expression interacted: When viewing fearful facial expressions, the ssVEP in response to threat context was amplified compared to other backgrounds. Together, these findings suggest that fearful faces elicit vigilance for potential threat in the visual periphery.
•We investigated mutual effects of faces and affective context on visual processing.•Frequency-tagging allows separating cortical processing of faces vs. context scenes.•Presence of fearful faces heightens cortical processing of threatening visual context.•Fearful faces signal danger and lead to vigilance for threat in the observer.
Journal Article
Social aversive generalization learning sharpens the tuning of visuocortical neurons to facial identity cues
2020
Defensive system activation promotes heightened perception of threat signals, and excessive attention to threat signals has been discussed as a contributory factor in the etiology of anxiety disorders. However, a mechanistic account of attentional modulation during fear-relevant processes, especially during fear generalization remains elusive. To test the hypothesis that social fear generalization prompts sharpened tuning in the visuocortical representation of social threat cues, 67 healthy participants underwent differential fear conditioning, followed by a generalization test in which participants viewed faces varying in similarity with the threat-associated face. We found that generalization of social threat sharpens visuocortical tuning of social threat cues, whereas ratings of fearfulness showed generalization, linearly decreasing with decreasing similarity to the threat-associated face. Moreover, individuals who reported greater anxiety in social situations also showed heightened sharpened tuning of visuocortical neurons to facial identity cues, indicating the behavioral relevance of visuocortical tuning during generalization learning.
Journal Article
Examining the impact of cue similarity and fear learning on perceptual tuning
2023
Past research on the effects of associative aversive learning on discrimination acuity has shown mixed results, including increases, decreases, and no changes in discrimination ability. An animal study found that the type of learning experience determined the direction and extent of learning-induced changes. The current preregistered web-based study aimed to translate these findings to humans. Experiment 1 (N = 245) compared changes in stimulus discrimination between simple learning (only one oriented grating cue), coarse differential conditioning (physically distinct cues), and fine differential conditioning (physically similar cues) as well as to their three respective control groups. The discrimination task consisted of a two-alternative-forced-choice task with oriented grating stimuli. During learning, a specific orientation was paired with unpleasant pictures. Our analysis using generative modeling demonstrated weak to moderate evidence that aversive learning did not alter discrimination acuity in any of the groups. In a follow-up experiment (N = 121), we replicated these findings despite successful learning trajectories in all three groups and a more detailed assessment of discrimination acuity. Contrary to prior assumptions, our findings indicate that aversive learning does not enhance perceptual discrimination, and the presence of additional safety cues does not appear to moderate this effect.
Journal Article
Attention mechanisms during predictable and unpredictable threat — A steady-state visual evoked potential approach
by
Wieser, Matthias J.
,
Reicherts, Philipp
,
Juravle, Georgiana
in
Adolescent
,
Adult
,
Anticipation, Psychological - physiology
2016
Fear is elicited by imminent threat and leads to phasic fear responses with selective attention, whereas anxiety is characterized by a sustained state of heightened vigilance due to uncertain danger. In the present study, we investigated attention mechanisms in fear and anxiety by adapting the NPU-threat test to measure steady-state visual evoked potentials (ssVEPs). We investigated ssVEPs across no aversive events (N), predictable aversive events (P), and unpredictable aversive events (U), signaled by four-object arrays (30s). In addition, central cues were presented during all conditions but predictably signaled imminent threat only during the P condition. Importantly, cues and context events were flickered at different frequencies (15Hz vs. 20Hz) in order to disentangle respective electrocortical responses. The onset of the context elicited larger electrocortical responses for U compared to P context. Conversely, P cues elicited larger electrocortical responses compared to N cues. Interestingly, during the presence of the P cue, visuocortical processing of the concurrent context was also enhanced. The results support the notion of enhanced initial hypervigilance to unpredictable compared to predictable threat contexts, while predictable cues show electrocortical enhancement of the cues themselves but additionally a boost of context processing.
Journal Article
Associative learning shapes visual discrimination in a web-based classical conditioning task
by
Stegmann, Yannik
,
Pauli, Paul
,
Andreatta, Marta
in
631/378/1595/1395
,
631/378/1595/2636
,
631/378/2613
2021
Threat detection plays a vital role in adapting behavior to changing environments. A fundamental function to improve threat detection is learning to differentiate between stimuli predicting danger and safety. Accordingly, aversive learning should lead to enhanced sensory discrimination of danger and safety cues. However, studies investigating the psychophysics of visual and auditory perception after aversive learning show divergent findings, and both enhanced and impaired discrimination after aversive learning have been reported. Therefore, the aim of this web-based study is to examine the impact of aversive learning on a continuous measure of visual discrimination. To this end, 205 participants underwent a differential fear conditioning paradigm before and after completing a visual discrimination task using differently oriented grating stimuli. Participants saw either unpleasant or neutral pictures as unconditioned stimuli (US). Results demonstrated sharpened visual discrimination for the US-associated stimulus (CS+), but not for the unpaired conditioned stimuli (CS−). Importantly, this finding was irrespective of the US’s valence. These findings suggest that associative learning results in increased stimulus salience, which facilitates perceptual discrimination in order to prioritize attentional deployment.
Journal Article
Raised Middle-Finger: Electrocortical Correlates of Social Conditioning with Nonverbal Affective Gestures
by
Pauli, Paul
,
Flaisch, Tobias
,
Wieser, Matthias J.
in
Adolescent
,
Anxiety
,
Biology and Life Sciences
2014
Humans form impressions of others by associating persons (faces) with negative or positive social outcomes. This learning process has been referred to as social conditioning. In everyday life, affective nonverbal gestures may constitute important social signals cueing threat or safety, which therefore may support aforementioned learning processes. In conventional aversive conditioning, studies using electroencephalography to investigate visuocortical processing of visual stimuli paired with danger cues such as aversive noise have demonstrated facilitated processing and enhanced sensory gain in visual cortex. The present study aimed at extending this line of research to the field of social conditioning by pairing neutral face stimuli with affective nonverbal gestures. To this end, electro-cortical processing of faces serving as different conditioned stimuli was investigated in a differential social conditioning paradigm. Behavioral ratings and visually evoked steady-state potentials (ssVEP) were recorded in twenty healthy human participants, who underwent a differential conditioning procedure in which three neutral faces were paired with pictures of negative (raised middle finger), neutral (pointing), or positive (thumbs-up) gestures. As expected, faces associated with the aversive hand gesture (raised middle finger) elicited larger ssVEP amplitudes during conditioning. Moreover, theses faces were rated as to be more arousing and unpleasant. These results suggest that cortical engagement in response to faces aversively conditioned with nonverbal gestures is facilitated in order to establish persistent vigilance for social threat-related cues. This form of social conditioning allows to establish a predictive relationship between social stimuli and motivationally relevant outcomes.
Journal Article
Context-Dependent Responses to the Spread of COVID-19 Among National and International Students During the First Lockdown: An Online Survey
by
Andreatta, Marta
,
Wieser, Matthias J.
,
Jongerling, Joran
in
Anxiety
,
COVID-19
,
Disease transmission
2023
Background:Restrictions to minimize social contact was necessary to prevent the spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus but may have impacted individuals’ mental well-being. Emotional responses are modulated by contextual information. Living abroad during the coronavirus disease 2019 (COVID-19) pandemic may have boosted the feeling of isolation as the context is unfamiliar.Objectives:This study compared the psychological impact of social distancing in national students (living in a familiar context) versus international students (living in an unfamiliar context).Methods:During March/April 2020 (first lockdown in the Netherlands), 850 university students completed an online survey. Structural equation modeling (SEM) was conducted to compare how students’ responses to the virus were predicted by health anxiety, emotional distress, and personal traits.Results:Compared with national students, international students showed higher levels in 4 identified factors (COVID-19-related worry, perceived risk of infection, distance from possibly contaminated objects, distance from social situations). The factors were mainly predicted by health anxiety across international students, while emotional distress and individual traits (eg, intolerance of uncertainty) played a role across national students.Conclusions:In the familiar context, individual characteristics (traits) predicted the responses to the virus, while the unfamiliar context drove individuals’ health-focused responses. Living in a foreign country is associated with psychological burdens and this should be considered by universities for more pronounced social support and clear references to health-related institutions.
Journal Article
Facial mimicry and the mirror neuron system: simultaneous acquisition of facial electromyography and functional magnetic resonance imaging
2012
Numerous studies have shown that humans automatically react with congruent facial reactions, i.e., facial mimicry, when seeing a vis-á-vis' facial expressions. The current experiment is the first investigating the neuronal structures responsible for differences in the occurrence of such facial mimicry reactions by simultaneously measuring BOLD and facial EMG in an MRI scanner. Therefore, 20 female students viewed emotional facial expressions (happy, sad, and angry) of male and female avatar characters. During picture presentation, the BOLD signal as well as M. zygomaticus major and M. corrugator supercilii activity were recorded simultaneously. Results show prototypical patterns of facial mimicry after correction for MR-related artifacts: enhanced M. zygomaticus major activity in response to happy and enhanced M. corrugator supercilii activity in response to sad and angry expressions. Regression analyses show that these congruent facial reactions correlate significantly with activations in the IFG, SMA, and cerebellum. Stronger zygomaticus reactions to happy faces were further associated to increased activities in the caudate, MTG, and PCC. Corrugator reactions to angry expressions were further correlated with the hippocampus, insula, and STS. Results are discussed in relation to core and extended models of the mirror neuron system (MNS).
Journal Article
Early cortical processing of natural and artificial emotional faces differs between lower and higher socially anxious persons
2009
Emotional facial expressions provide critical information for social interactions. Above all, angry faces are assumed to reflect potential social threat. We investigated event-related potentials (ERPs) triggered by natural and artificial faces expressing fear, anger, happiness or no emotion in participants with low and high levels of social anxiety. Overall, artificial faces elicited stronger P100 and N170 responses than natural faces. Additionally, the N170 component was larger for emotional compared to neutral facial expressions. Social anxiety was associated with an enhanced emotional modulation of the early posterior negativity (EPN) in response to fearful and angry facial expressions. Additionally, while the late positive potential (LPP) was larger for emotional than for neutral faces in low socially anxious participants, LPPs of higher socially anxious participants did not differ. LPPs might therefore be enhanced in higher socially anxious participants for both emotional and neutral faces. Furthermore, the modulations of the EPN and LPP were comparable between natural and artificial faces. These results indicate that social anxiety influences early perceptual processing of faces and that artificial faces are suitable for psychophysiological emotion research.
Journal Article