Publications by authors named "Markus Junghöfer"

77 Publications

Ratings of Emotional Expressions in Static and Dynamic Facial Recordings Before and After Upper Face Botulinum Injections - An Observational Prospective Study.

Aesthet Surg J 2020 Dec 25. Epub 2020 Dec 25.

Department of Otorhinolaryngology, Jena University Hospital, Jena, Germany.

Background: Botulinum toxin A (BTX) is a neurotoxin widely used for facial aesthetics. It causes dose-dependent muscle paralysis. It was hypothesized that treatment of mimic muscles with BTX might have a positive impact on emotional expression in static images (photos), but a negative impact in dynamic recordings (videos).

Objective: Comparison of emotional expression recorded in photos and videos before and after treatment with BTX.

Methods: Twenty healthy women (mean age: 45) received a dose of 19 mouse units (XEOMIN®, Merz, Frankfurt am Main, Germany) into the procerus, occipitofrontalis and orbicularis oculi muscles. Photos and videos of the participant's faces with neutral and happy expressions were recorded before treatment and two weeks later. Recordings were rated by naïve raters blind to the conditions and in balanced order.

Results: Videos compared to photos were generally rated as more pleasant, arousing, attractive and genuine (all ps>.001). This was especially the case for videos with neutral expression (p=.003). Independent of presentation mode and facial expression, women were rated as more attractive after BTX treatment (p=.03).

Conclusion: In contrast to the hypothesis, the reduced mobility had no detectable negative impact on dynamic emotional expression, but videos received more positive ratings, particularly for neutral expressions. It is thus recommended to assess emotional expression with dynamic recordings in order to evaluate the effects of treatment with BTX. BTX seems to improve perceived attractiveness, though the cause of this effect remains unclear.
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http://dx.doi.org/10.1093/asj/sjaa393DOI Listing
December 2020

Testing the effect of tACS over parietal cortex in modulating endogenous alpha rhythm and temporal integration windows in visual perception.

Eur J Neurosci 2020 Oct 23. Epub 2020 Oct 23.

Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster, Münster, Germany.

Neural oscillations in the alpha band (8-12 Hz) have been proposed as a key mechanism for the temporal resolution of visual perception. Higher alpha frequencies have been related to improved segregation of visual events over time, whereas lower alpha frequencies have been related to improved temporal integration. Similarly, also the phase of ongoing alpha has been shown to correlate with temporal integration/segregation. To test a causal relationship between alpha oscillations and perception, we here employed multi-channel transcranial alternating current stimulation (mc-tACS) over the right parietal cortex, whereas participants performed a visual temporal integration/segregation task that used identical stimuli with different instructions. Before and after mc-tACS we recorded the resting-state electroencephalogram (EEG) to extract the individual alpha frequency (IAF) and delivered electrical stimulation at slightly slower and faster frequencies (IAF±2 Hz). We hypothesized that this would not only drive endogenous alpha rhythms, but also affect temporal integration and segregation in an opposite way. However, the mc-tACS protocol used here did not consistently increase or decrease the IAF after the stimulation and did not affect temporal integration/segregation accuracy as expected. Although we found some preliminary evidence for an influence of tACS phase on temporal integration accuracy, the ongoing phase of mc-tACS oscillations did not reliably modulate temporal integration/segregation accuracy in a sinusoidal way as would have been predicted by an effective entrainment of brain oscillations. These findings may guide future studies using different stimulation montages for investigating the role of cortical alpha oscillations for human vision.
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http://dx.doi.org/10.1111/ejn.15017DOI Listing
October 2020

Acute aerobic exercise enhances pleasant compared to unpleasant visual scene processing.

Brain Cogn 2020 08 13;143:105595. Epub 2020 Jun 13.

Institute for Biomagnetism and Biosignalanalysis, University of Muenster, Muenster, Germany; Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster, Germany.

Although acute aerobic exercise benefits different aspects of emotional functioning, it is unclear how exercise influences the processing of emotional stimuli and which brain mechanisms support this relationship. We assessed the influence of acute aerobic exercise on valence biases (preferential processing of negative/positive pictures) by performing source reconstructions of participants' brain activity after they viewed emotional scenes. Twenty-four healthy participants (12 women) were tested in a randomized and counterbalanced design that consisted of three experimental protocols, each lasting 30 min: low-intensity exercise (Low-Int); moderate-intensity exercise (Mod-Int); and a seated rest condition (REST). After each of the protocols, participants viewed negative and positive pictures, during which event-related magnetic fields were recorded. Analyses revealed that exercise strongly impacted the valence processing of emotional scenes within a widely distributed left hemispheric spatio-temporal cluster between 190 and 310 ms after picture onset. Brain activity in this cluster showed that a negativity bias at REST (negative > positive picture processing) diminished after the Low-Int condition (positive = negative) and even reversed to a positivity bias after the Mod-Int condition (positive > negative). Thus, acute aerobic exercise of low and moderate intensities induces a positivity bias which is reflected in early, automatic processes.
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http://dx.doi.org/10.1016/j.bandc.2020.105595DOI Listing
August 2020

Contextual information resolves uncertainty about ambiguous facial emotions: Behavioral and magnetoencephalographic correlates.

Neuroimage 2020 07 7;215:116814. Epub 2020 Apr 7.

Institute for Biomagnetism and Biosignalanalysis, University Hospital Münster, Münster, Germany; Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster, Germany.

Environmental conditions bias our perception of other peoples' facial emotions. This becomes quite relevant in potentially threatening situations, when a fellow's facial expression might indicate potential danger. The present study tested the prediction that a threatening environment biases the recognition of facial emotions. To this end, low- and medium-expressive happy and fearful faces (morphed to 10%, 20%, 30%, or 40% emotional) were presented within a context of instructed threat-of-shock or safety. Self-reported data revealed that instructed threat led to a biased recognition of fearful, but not happy facial expressions. Magnetoencephalographic correlates revealed spatio-temporal clusters of neural network activity associated with emotion recognition and contextual threat/safety in early to mid-latency time intervals in the left parietal cortex, bilateral prefrontal cortex, and the left temporal pole regions. Early parietal activity revealed a double dissociation of face-context information as a function of the expressive level of facial emotions: When facial expressions were difficult to recognize (low-expressive), contextual threat enhanced fear processing and contextual safety enhanced processing of subtle happy faces. However, for rather easily recognizable faces (medium-expressive) the left hemisphere (parietal cortex, PFC, and temporal pole) showed enhanced activity to happy faces during contextual threat and fearful faces during safety. Thus, contextual settings reduce the salience threshold and boost early face processing of low-expressive congruent facial emotions, whereas face-context incongruity or mismatch effects drive neural activity of easier recognizable facial emotions. These results elucidate how environmental settings help recognize facial emotions, and the brain mechanisms underlying the recognition of subtle nuances of fear.
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http://dx.doi.org/10.1016/j.neuroimage.2020.116814DOI Listing
July 2020

Repeated noninvasive stimulation of the ventromedial prefrontal cortex reveals cumulative amplification of pleasant compared to unpleasant scene processing: A single subject pilot study.

PLoS One 2020 21;15(1):e0222057. Epub 2020 Jan 21.

Institute for Biomagnetism and Biosignalanalysis, University of Muenster, Muenster, Germany.

The ventromedial prefrontal cortex (vmPFC) is a major hub of the reward system and has been shown to activate specifically in response to pleasant / rewarding stimuli. Previous studies demonstrate enhanced pleasant cue reactivity after single applications of transcranial direct current stimulation (tDCS) to the vmPFC. Here we present a pilot case study in which we assess the cumulative impact of multiple consecutive vmPFC-tDCS sessions on the processing of visual emotional stimuli in an event-related MEG recording design. The results point to stable modulation of increased positivity biases (pleasant > unpleasant stimulus signal strength) after excitatory vmPFC stimulation and a reversed pattern (pleasant < unpleasant) after inhibitory stimulation across five consecutive tDCS sessions. Moreover, cumulative effects of these emotional bias modulations were observable for several source-localized spatio-temporal clusters, suggesting an increase in modulatory efficiency by repeated tDCS sessions. This pilot study provides evidence for improvements in the effectiveness and utility of a novel tDCS paradigm in the context of emotional processing.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0222057PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6974138PMC
April 2020

Theranostic markers for personalized therapy of spider phobia: Methods of a bicentric external cross-validation machine learning approach.

Int J Methods Psychiatr Res 2020 06 8;29(2):e1812. Epub 2019 Dec 8.

Department of Psychiatry and Psychotherapy, University of Münster, Münster, Germany.

Objectives: Embedded in the Collaborative Research Center "Fear, Anxiety, Anxiety Disorders" (CRC-TRR58), this bicentric clinical study aims at identifying biobehavioral markers of treatment (non-)response by applying machine learning methodology with an external cross-validation protocol. We hypothesize that a priori prediction of treatment (non-)response is possible in a second, independent sample based on multimodal markers.

Methods: One-session virtual reality exposure treatment (VRET) with patients with spider phobia was conducted on two sites. Clinical, neuroimaging, and genetic data were assessed at baseline, post-treatment and after 6 months. The primary and secondary outcomes defining treatment response are as follows: 30% reduction regarding the individual score in the Spider Phobia Questionnaire and 50% reduction regarding the individual distance in the behavioral avoidance test.

Results: N = 204 patients have been included (n = 100 in Würzburg, n = 104 in Münster). Sample characteristics for both sites are comparable.

Discussion: This study will offer cross-validated theranostic markers for predicting the individual success of exposure-based therapy. Findings will support clinical decision-making on personalized therapy, bridge the gap between basic and clinical research, and bring stratified therapy into reach. The study is registered at ClinicalTrials.gov (ID: NCT03208400).
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http://dx.doi.org/10.1002/mpr.1812DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7301283PMC
June 2020

Biased emotional attention in patients with dental phobia.

Eur J Neurosci 2019 01 21;49(2):290-302. Epub 2018 Dec 21.

Institute for Biomagnetism and Biosignal Analysis, University of Muenster, Muenster, Germany.

Biased motivated attention towards phobia-relevant pictures is a typical finding in specific phobia. In the visual system, the allocation of motivated attention is indexed by two event-related potential components - the Early Posterior Negativity and the Late Positive Potential. Enhanced Early Posterior Negativity and Late Positive Potential amplitudes are reliably observed in specific phobia such as, for instance, snake, spider, or blood-injection-injury phobia and to some extent also in dental phobia. However, regarding dental phobia results are sparse and its theoretical concept is not undisputed. To further elucidate the electrophysiological characteristics of dental phobia, we investigated visual emotional processing in dental phobia patients and controls. Subjects viewed neutral, phobia-irrelevant and phobia-relevant pictures while magnetoencephalographic and behavioural measures were recorded. All patients reported a history of traumatic experiences and depressive and anxiety symptoms, as well as dissociative and posttraumatic symptoms. In the magnetoencephalography, patients showed generally less evoked neural activation at parietal and temporal regions and a reduced differentiation between picture categories compared to controls. At the behavioural level, patients rated phobia-relevant pictures as clearly more negative as did controls. In contrast to previous reports, our results suggest that dental phobia cannot be associated with the typical effects of biased motivated attention seen in other specific phobias. Instead, results indicate that dental phobia shares typical characteristics with mild forms of posttraumatic stress disorder.
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http://dx.doi.org/10.1111/ejn.14295DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6590303PMC
January 2019

Identity and expression processing during classical conditioning with faces.

Psychophysiology 2018 10 2;55(10):e13203. Epub 2018 Aug 2.

Institute for Biomagnetism and Biosignalanalysis, University Hospital Münster, Münster, Germany.

In classical conditioning, conditioned responses (CRs) to aversively paired (CS+) relative to unpaired (CS-) face images are often interpreted in terms of the specific individual displayed in the CS + face image having adopted an aversive emotional connotation. This interpretation requires conditioning to rely on an association between CS + face identity and the occurrence of the aversive event (UCS). Here, we tested this requirement assuming that if an association between CS + face identity and UCS occurrence is established, CRs to originally conditioned face images should transfer to novel images of same-identity faces. Forty-eight participants underwent MultiCS conditioning with eight neutral faces as CSs and electric shock as UCS. Central, peripheral, evaluative, and behavioral CRs signaled successful emotional learning (as reported in Pastor et al., 2015). Behavioral and EEG responses of consecutive passive viewing showed enhanced reactions to novel angry and happy expressions of previously shocked CS + versus nonshocked CS- identities, indicating successful CR transfer within the dimension of face identity. Investigating the nature of CR transfer, EEG revealed an interaction of identity and expression information during face processing that followed emotional congruency (i.e., stronger reactions to congruent angry CS + and happy CS- vs. incongruent angry CS- and happy CS + compounds). While correlates of transfer appeared in late and midlatency time intervals, the congruency interaction became significant within the first 100 ms of face processing. Our results suggest conditioning to rely on an association of UCS occurrence with CS + identity and point to fast dynamic interrelations between identity and expression processing.
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http://dx.doi.org/10.1111/psyp.13203DOI Listing
October 2018

Modulating Emotion Perception: Opposing Effects of Inhibitory and Excitatory Prefrontal Cortex Stimulation.

Biol Psychiatry Cogn Neurosci Neuroimaging 2018 04 29;3(4):329-336. Epub 2017 Dec 29.

Institute for Biomagnetism and Biosignal Analysis and Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster, Germany. Electronic address:

Background: Excitatory repetitive transcranial magnetic stimulation (rTMS) of the left dorsolateral prefrontal cortex (dlPFC) is approved by the U.S. Food and Drug Administration for the treatment of adult patients with treatment-resistant major depressive disorder (MDD). This stimulation is supposed to restore excitability of prefrontal cortex regions that exhibit diminished regulation of emotion-generative systems in MDD. Based on the valence lateralization hypothesis, inhibitory rTMS of the right dlPFC has also been applied in MDD. This approach has proved to be effective, although meta-analyses of emotional perception and affective regulation in healthy control subjects and patients with depression do not support functional asymmetries within dlPFC regions.

Methods: To shed more light on this discrepancy, the effects of excitatory and inhibitory rTMS of the right dlPFC on visual emotional perception were compared in two groups of 41 healthy participants overall. Before and after rTMS stimulation, participants viewed fearful and neutral faces while whole-head magnetoencephalography was recorded and supplemented by behavioral tests.

Results: Visual sensory processing of fearful facial expressions, relative to neutral facial expressions, was reduced after excitatory stimulation and was increased after inhibitory stimulation within right occipital and right temporal regions. Correspondingly, after excitatory rTMS compared with inhibitory rTMS, participants displayed relatively reduced reaction times in an emotion discrimination task and showed reduced emotional arousal.

Conclusions: These results support the hypothesis that excitatory rTMS compared with inhibitory rTMS of the right dlPFC strengthens top-down control of aversive stimuli in healthy control subjects, which should encourage more research on mechanisms of excitatory/inhibitory dlPFC-rTMS protocols in general and on neuromodulatory treatment of MDD.
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http://dx.doi.org/10.1016/j.bpsc.2017.12.007DOI Listing
April 2018

Noninvasive stimulation of the ventromedial prefrontal cortex modulates emotional face processing.

Neuroimage 2018 07 29;175:388-401. Epub 2018 Mar 29.

Institute for Biomagnetism and Biosignalanalysis, University of Muenster, Germany; Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Germany. Electronic address:

The ventromedial prefrontal cortex (vmPFC) is associated with emotional states that can be characterized as positive affect. Moreover, a variety of psychiatric disorders that are associated with disturbed reactions toward reward- or safety-signaling stimuli reveal functional or structural anomalies within this area. Thus, neuromodulation of this region via transcranial direct current stimulation (tDCS) offers an attractive opportunity to noninvasively influence pleasant emotional and reward processing. Recent experiments revealed hemodynamic and electrophysiological evidence for valence specific modulations of emotional scene processing after excitatory and inhibitory tDCS of the vmPFC. Here, we identified that tDCS modulation of vmPFC during emotional face processing results in effects convergent with scene processing, in that excitatory tDCS increased neural reactivity during happy compared to fearful face perception, whereas inhibitory stimulation led to a converse effect. In addition, behavioral data (affect identification of ambiguous expressive faces) revealed a bias toward preferential processing of happy compared to fearful faces after excitatory compared to after inhibitory stimulation. These results further support the vmPFC as an appropriate target for noninvasive neuromodulation of an appetitive processing network in patients suffering from disturbed cognition of reward- and safety-signaling stimuli. It should however be noted that electrophysiological pre-tDCS differences at earlier time intervals of emotional face and scene processing appeared amplified by tDCS, which remains to be investigated.
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http://dx.doi.org/10.1016/j.neuroimage.2018.03.067DOI Listing
July 2018

Targeting Heterogeneous Findings in Neuronal Oscillations in Tinnitus: Analyzing MEG Novices and Mental Health Comorbidities.

Front Psychol 2018 2;9:235. Epub 2018 Mar 2.

Institute for Biomagnetism and Biosignalanalysis, University Hospital of Münster, Münster, Germany.

Tinnitus is a prevalent phenomenon and bothersome for people affected by it. Its occurrence and maintenance have a clear neuroscientific tie and one aspect are differences in the neuronal oscillatory pattern, especially in auditory cortical areas. As studies in this field come to different results, the aim of this study was to analyze a large number of participants to achieve more stable results. Furthermore, we expanded our analysis to two variables of potential influence, namely being a novice to neuroscientific measurements and the exclusion of psychological comorbidities. Oscillatory brain activity of 88 subjects (46 with a chronic tinnitus percept, 42 without) measured in resting state by MEG was investigated. In the analysis based on the whole group, in sensor space increased activity in the delta frequency band was found in tinnitus patients. Analyzing the subgroup of novices, a significant difference in the theta band emerged additionally to the delta band difference (sensor space). Localizing the origin of the activity, we found a difference in theta and gamma band for the auditory regions for the whole group and the same significant difference in the subgroup of novices. However, no differences in oscillatory activity were observed between tinnitus and control groups once subjects with mental health comorbidity were excluded. Against the background of previous studies, the study at hand underlines the fragility of the results in the field of neuronal cortical oscillations in tinnitus. It supports the body of research arguing for low frequency oscillations and gamma band activity as markers associated with tinnitus.
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http://dx.doi.org/10.3389/fpsyg.2018.00235DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5841018PMC
March 2018

No differential effects to facial expressions under continuous flash suppression: An event-related potentials study.

Neuroimage 2017 12 20;163:276-285. Epub 2017 Sep 20.

Institute of Medical Psychology and Systems Neuroscience, Germany. Electronic address:

In recent years continuous flash suppression (CFS) has become a popular "blinding" technique for the investigation of nonconscious affective processing since it elicits potent and long-lasting suppression of conscious visual perception. While the majority of studies provides some positive evidence for nonconscious affective processing, there are also studies reporting their absence. Several methodological variations may give rise to this discrepancy: with respect to the experimental paradigm these variations pertain to the likelihood of residual stimulus visibility on the level of individual participants and single trials. Concerning the statistical analysis they relate to the procedures applied to assess whether detection performance is at chance level and whether the outcome measure does or does not depend on the affective stimulus category. In the present study we determined individual eye dominance and individual stimulus contrast in pretests, measured objective and subjective awareness online and applied Bayesian statistics to estimate the likelihood for the null hypothesis. Event-related potentials (ERPs) were measured while participants were subjected to fearful, happy, and neutral faces in a conscious as well as in a nonconscious CFS condition. In the conscious condition, expected emotion effects were observed in the ERP components N170/EPN and LPP. However, despite high statistical power, no effects of emotional expression were found in the nonconscious condition and the absence of nonconscious affective processing under the tested conditions was substantially more likely than its presence. We discuss whether CFS disrupts affective processing completely if thoroughly applied or whether positive and negative findings should be integrated under a two-threshold framework of nonconscious processing.
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http://dx.doi.org/10.1016/j.neuroimage.2017.09.034DOI Listing
December 2017

Noninvasive Stimulation of the Ventromedial Prefrontal Cortex Enhances Pleasant Scene Processing.

Cereb Cortex 2017 06;27(6):3449-3456

Department of Psychology & Neuroscience, BioImaging Research Center, University of Georgia, Athens, GA 30602, USA.

Depressive patients typically show biased attention towards unpleasant and away from pleasant emotional material. Imaging studies suggest that dysfunctions in a distributed neural network, including the ventromedial prefrontal cortex (vmPFC), are associated with this processing bias. Accordingly, changes in vmPFC activation should mediate changes in processing of emotional stimuli. Here, we investigated the effect of inhibitory and excitatory transcranial direct current stimulation (tDCS) of the vmPFC on emotional scene processing in two within-subject experiments using functional magnetic resonance imaging (fMRI) and magnetoencephalography (MEG). Both studies showed that excitatory relative to inhibitory tDCS amplifies processing of pleasant compared to unpleasant scenes in healthy participants. This modulatory effect occurred in a distributed network including sensory and prefrontal cortex regions and was visible during very early to late processing stages. Findings are discussed with regard to neurophysiological models of emotional processing. The convergence of stimulation effects across independent groups of healthy participants and complementary neuroimaging methods (fMRI, MEG) provides a basis for further investigation of a potentially therapeutic use of this novel stimulation approach in patients with depression or other affective disorders.
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http://dx.doi.org/10.1093/cercor/bhx073DOI Listing
June 2017

An evil face? Verbal evaluative multi-CS conditioning enhances face-evoked mid-latency magnetoencephalographic responses.

Soc Cogn Affect Neurosci 2017 04;12(4):695-705

Department of Psychology, Affective Neuropsychology Unit.

Humans have a remarkable capacity for rapid affective learning. For instance, using first-order US such as odors or electric shocks, magnetoencephalography (MEG) studies of multi-CS conditioning demonstrate enhanced early (<150 ms) and mid-latency (150-300 ms) visual evoked responses to affectively conditioned faces, together with changes in stimulus evaluation. However, particularly in social contexts, human affective learning is often mediated by language, a class of complex higher-order US. To elucidate mechanisms of this type of learning, we investigate how face processing changes following verbal evaluative multi-CS conditioning. Sixty neutral expression male faces were paired with phrases about aversive crimes (30) or neutral occupations (30). Post conditioning, aversively associated faces evoked stronger magnetic fields in a mid-latency interval between 220 and 320 ms, localized primarily in left visual cortex. Aversively paired faces were also rated as more arousing and more unpleasant, evaluative changes occurring both with and without contingency awareness. However, no early MEG effects were found, implying that verbal evaluative conditioning may require conceptual processing and does not engage rapid, possibly sub-cortical, pathways. Results demonstrate the efficacy of verbal evaluative multi-CS conditioning and indicate both common and distinct neural mechanisms of first- and higher-order multi-CS conditioning, thereby informing theories of associative learning.
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http://dx.doi.org/10.1093/scan/nsw179DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5390753PMC
April 2017

Hypervigilance-avoidance in children with anxiety disorders: magnetoencephalographic evidence.

J Child Psychol Psychiatry 2017 01 8;58(1):103-112. Epub 2016 Sep 8.

Institute for Biomagnetism and Biosignalanalysis, University Hospital Münster, Münster, Germany.

Background: An altered pattern of threat processing is deemed critical for the development of anxiety disorders (AD). According to the hypervigilance-avoidance hypothesis, AD patients show hypervigilance to threat cues at early stages of processing but avoid threat cues at later stages of processing. Consistently, adults with AD show enhanced neurophysiological responses to threat in early time windows and reduced responses to threat in late time windows. The presence of such a hypervigilance-avoidance effect and its underlying neural sources remain to be determined in clinically anxious children.

Methods: Twenty-three children diagnosed with an AD and 23 healthy control children aged 8-14 years saw faces with angry and neutral expressions while whole-head magnetoencephalography (MEG) was recorded. Neural sources were estimated based on L2-Minimum Norm inverse source modeling and analyzed in early, midlatency, and late time windows.

Results: In visual cortical regions, early threat processing was relatively enhanced in patients compared to controls, whereas this relation was inverted in a late interval. Consistent with the idea of affective regulation, the right dorsolateral prefrontal cortex revealed relatively reduced inhibition of early threat processing but revealed enhanced inhibition at a late interval in patients. Both visual-sensory and prefrontal effects were correlated with individual trait anxiety.

Conclusions: These results support the hypothesis of early sensory hypervigilance followed by later avoidance of threat in anxiety disordered children, presumably modulated by early reduced and later enhanced prefrontal inhibition. This neuronal hypervigilance-avoidance pattern unfolds gradually with increasing trait anxiety, reflecting a progressively biased allocation of attention to threat.
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http://dx.doi.org/10.1111/jcpp.12617DOI Listing
January 2017

Healthy individuals maintain adaptive stimulus evaluation under predictable and unpredictable threat.

Neuroimage 2016 Aug 18;136:174-85. Epub 2016 May 18.

Institute for Biomagnetism and Biosignalanalysis, University Hospital Muenster, D-48149 Muenster, Germany; Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster, Germany.

The anxiety inducing paradigms such as the threat-of-shock paradigm have provided ample data on the emotional processing of predictable and unpredictable threat, but little is known about the processing of aversive, threat-irrelevant stimuli in these paradigms. We investigated how the predictability of threat influences the neural visual processing of threat-irrelevant fearful and neutral faces. Thirty-two healthy individuals participated in an NPU-threat test, consisting of a safe or neutral condition (N) and a predictable (P) as well as an unpredictable (U) threat condition, using audio-visual threat stimuli. In all NPU-conditions, we registered participants' brain responses to threat-irrelevant faces via magnetoencephalography. The data showed that increasing unpredictability of threat evoked increasing emotion regulation during face processing predominantly in dorsolateral prefrontal cortex regions during an early to mid-latency time interval. Importantly, we obtained only main effects but no significant interaction of facial expression and conditions of different threat predictability, neither in behavioral nor in neural data. Healthy individuals with average trait anxiety are thus able to maintain adaptive stimulus evaluation processes under predictable and unpredictable threat conditions.
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http://dx.doi.org/10.1016/j.neuroimage.2016.05.041DOI Listing
August 2016

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

Behav Brain Res 2016 07 29;307:84-91. Epub 2016 Mar 29.

Institute for Biogmagnetism and Biosignalanalysis, University of Muenster, Germany. Electronic address:

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.
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http://dx.doi.org/10.1016/j.bbr.2016.03.045DOI Listing
July 2016

Impact of electroconvulsive therapy on magnetoencephalographic correlates of dysfunctional emotional processing in major depression.

Eur Neuropsychopharmacol 2016 Apr 8;26(4):684-92. Epub 2016 Feb 8.

Institute for Biogmagnetism and Biosignal Analysis, University of Münster, Germany; Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster, D-48151 Münster, Germany. Electronic address:

In major depressive disorder (MDD), electrophysiological and imaging studies provide evidence for a reduced neural activity in parietal and dorsolateral prefrontal regions. In the present study, neural correlates and temporal dynamics of visual affective perception have been investigated in patients with unipolar depression in a pre/post treatment design using magnetoencephalography (MEG). Nineteen in-patients and 19 balanced healthy controls passed MEG measurement while passively viewing pleasant, unpleasant and neutral pictures. After a 4-week treatment with electroconvulsive therapy or 4-week waiting period without intervention respectively, 16 of these patients and their 16 corresponding controls participated in a second MEG measurement. Before treatment neural source estimations of magnetic fields evoked by the emotional scenes revealed a general bilateral parietal hypoactivation in depressed patients compared to controls predominately at early and mid-latency time intervals. Successful ECT treatment, as reflected by a decline in clinical scores (Hamilton Depression Scale; HAMD) led to a normalization of this distinct parietal hypoactivation. Effective treatment was also accompanied by relatively increased neural activation at right temporo-parietal regions. The present study indicates dysfunctional parietal information processing and attention processes towards emotional stimuli in MDD patients which can be returned to normal by ECT treatment. Since convergent neural hypoactivations and treatment effects have recently been shown in MDD patients before and after pharmacological therapy, this electrophysiological correlate might serve as a biomarker for objective treatment evaluation and thereby potentially advance treatment options and support the prediction of individual treatment responses.
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http://dx.doi.org/10.1016/j.euroneuro.2016.02.005DOI Listing
April 2016

Modulatory Effects of Attention on Lateral Inhibition in the Human Auditory Cortex.

PLoS One 2016 22;11(2):e0149933. Epub 2016 Feb 22.

Institute for Biomagnetism and Biosignalanalysis, University Hospital Muenster, Muenster, Germany.

Reduced neural processing of a tone is observed when it is presented after a sound whose spectral range closely frames the frequency of the tone. This observation might be explained by the mechanism of lateral inhibition (LI) due to inhibitory interneurons in the auditory system. So far, several characteristics of bottom up influences on LI have been identified, while the influence of top-down processes such as directed attention on LI has not been investigated. Hence, the study at hand aims at investigating the modulatory effects of focused attention on LI in the human auditory cortex. In the magnetoencephalograph, we present two types of masking sounds (white noise vs. withe noise passing through a notch filter centered at a specific frequency), followed by a test tone with a frequency corresponding to the center-frequency of the notch filter. Simultaneously, subjects were presented with visual input on a screen. To modulate the focus of attention, subjects were instructed to concentrate either on the auditory input or the visual stimuli. More specific, on one half of the trials, subjects were instructed to detect small deviations in loudness in the masking sounds while on the other half of the trials subjects were asked to detect target stimuli on the screen. The results revealed a reduction in neural activation due to LI, which was larger during auditory compared to visual focused attention. Attentional modulations of LI were observed in two post-N1m time intervals. These findings underline the robustness of reduced neural activation due to LI in the auditory cortex and point towards the important role of attention on the modulation of this mechanism in more evaluative processing stages.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0149933PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4763022PMC
July 2016

The Relevance of Interoception in Chronic Tinnitus: Analyzing Interoceptive Sensibility and Accuracy.

Biomed Res Int 2015 25;2015:487372. Epub 2015 Oct 25.

Institute for Biomagnetism and Biosignalanalysis, University Hospital of Münster, Malmedyweg 15, 48149 Münster, Germany.

In order to better understand tinnitus and distress associated with tinnitus, psychological variables such as emotional and cognitive processing are a central element in theoretical models of this debilitating condition. Interoception, that is, the perception of internal processes, may be such a psychological factor relevant to tinnitus. Against this background, 20 participants suffering from chronic tinnitus and 20 matched healthy controls were tested with questionnaires, assessing interoceptive sensibility, and participated in two tasks, assessing interoceptive accuracy: the Schandry task, a heartbeat estimation assignment, and a skin conductance fluctuations perception task assessing the participants' ability to perceive phasic increases in sympathetic activation were used. To test stress reactivity, a construct tightly connected to tinnitus onset, we also included a stress induction. No differences between the groups were found for interoceptive accuracy and sensibility. However, the tinnitus group tended to overestimate the occurrence of phasic activation. Loudness of the tinnitus was associated with reduced interoceptive performance under stress. Our results indicate that interoceptive sensibility and accuracy do not play a significant role in tinnitus. However, tinnitus might be associated with a tendency to overestimate physical changes.
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http://dx.doi.org/10.1155/2015/487372DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4637048PMC
August 2016

Magnetoencephalographic Correlates of Emotional Processing in Major Depression Before and After Pharmacological Treatment.

Int J Neuropsychopharmacol 2015 Aug 9;19(2). Epub 2015 Aug 9.

Department of Psychiatry, University of Muenster, Germany (Drs Domschke, Zwanzger, Knoke, and Arolt); Department of Psychiatry, University of Wuerzburg, Germany (Dr Domschke); Institute of Biomagnetism and Biosignal Analysis, University of Muenster, Germany (Ms Rehbein and Klinkenberg, Drs Steinberg, Dobel, Pantev, and Junghofer); Department of Radiology, University of Muenster, Germany (Dr Kugel); Department of Psychosomatic Medicine, University of Leipzig, Germany (Dr Kersting).

Background: In major depressive disorder (MDD), electrophysiological and imaging studies suggest reduced neural activity in the parietal and dorsolateral prefrontal cortex regions. In the present study, neural correlates of emotional processing in MDD were analyzed for the first time in a pre-/post-treatment design by means of magnetoencephalography (MEG), allowing for detecting temporal dynamics of brain activation.

Methods: Twenty-five medication-free Caucasian in-patients with MDD and 25 matched controls underwent a baseline MEG session with passive viewing of pleasant, unpleasant, and neutral pictures. Fifteen patients were followed-up with a second MEG session after 4 weeks of antidepressant monopharmacotherapy with mirtazapine. The corresponding controls received no intervention between the measurements. The clinical course of depression was assessed using the Hamilton Depression scale.

Results: Prior to treatment, an overall neocortical hypoactivation during emotional processing, particularly at the parietal regions and areas at the right temporoparietal junction, as well as abnormal valence-specific reactions at the right parietal and bilateral dorsolateral prefrontal cortex (dlPFC) regions were observed in patients compared to controls. These effects occurred <150 ms, suggesting dysfunctional processing of emotional stimuli at a preconscious level. Successful antidepressant treatment resulted in a normalization of the hypoactivation at the right parietal and right temporoparietal regions. Accordingly, both dlPFC regions revealed an increase of activity after therapy.

Conclusions: The present study provides neurophysiological evidence for dysfunctional emotional processing in a fronto-parieto-temporal network, possibly contributing to the pathogenesis of MDD. These activation patterns might have the potential to serve as biomarkers of treatment success.
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http://dx.doi.org/10.1093/ijnp/pyv093DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4772824PMC
August 2015

Rapid prefrontal cortex activation towards aversively paired faces and enhanced contingency detection are observed in highly trait-anxious women under challenging conditions.

Front Behav Neurosci 2015 10;9:155. Epub 2015 Jun 10.

Institute for Biomagnetism and Biosignalanalysis, University Hospital Münster Münster, Germany ; Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster Münster, Germany.

Relative to healthy controls, anxiety-disorder patients show anomalies in classical conditioning that may either result from, or provide a risk factor for, clinically relevant anxiety. Here, we investigated whether healthy participants with enhanced anxiety vulnerability show abnormalities in a challenging affective-conditioning paradigm, in which many stimulus-reinforcer associations had to be acquired with only few learning trials. Forty-seven high and low trait-anxious females underwent MultiCS conditioning, in which 52 different neutral faces (CS+) were paired with an aversive noise (US), while further 52 faces (CS-) remained unpaired. Emotional learning was assessed by evaluative (rating), behavioral (dot-probe, contingency report), and neurophysiological (magnetoencephalography) measures before, during, and after learning. High and low trait-anxious groups did not differ in evaluative ratings or response priming before or after conditioning. High trait-anxious women, however, were better than low trait-anxious women at reporting CS+/US contingencies after conditioning, and showed an enhanced prefrontal cortex (PFC) activation towards CS+ in the M1 (i.e., 80-117 ms) and M170 time intervals (i.e., 140-160 ms) during acquisition. These effects in MultiCS conditioning observed in individuals with elevated trait anxiety are consistent with theories of enhanced conditionability in anxiety vulnerability. Furthermore, they point towards increased threat monitoring and detection in highly trait-anxious females, possibly mediated by alterations in visual working memory.
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http://dx.doi.org/10.3389/fnbeh.2015.00155DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4461824PMC
June 2015

Facing Challenges in Differential Classical Conditioning Research: Benefits of a Hybrid Design for Simultaneous Electrodermal and Electroencephalographic Recording.

Front Hum Neurosci 2015 9;9:336. Epub 2015 Jun 9.

Department of Basic and Clinical Psychology, and Psychobiology, Universitat Jaume I , Castellón , Spain.

Several challenges make it difficult to simultaneously investigate central and autonomous nervous system correlates of conditioned stimulus (CS) processing in classical conditioning paradigms. Such challenges include, for example, the discrepant requirements of electroencephalography (EEG) and electrodermal activity (EDA) recordings with regard to multiple repetitions of conditions and sufficient trial duration. Here, we propose a MultiCS conditioning set-up, in which we increased the number of CSs, decreased the number of learning trials, and used trials of short and long durations for meeting requirements of simultaneous EEG-EDA recording in a differential aversive conditioning task. Forty-eight participants underwent MultiCS conditioning, in which four neutral faces (CS+) were paired four times each with aversive electric stimulation (unconditioned stimulus) during acquisition, while four different neutral faces (CS-) remained unpaired. When comparing after relative to before learning measurements, EEG revealed an enhanced centro-posterior positivity to CS+ vs. CS- during 368-600 ms, and subjective ratings indicated CS+ to be less pleasant and more arousing than CS-. Furthermore, changes in CS valence and arousal were strong enough to bias subjective ratings when faces of CS+/CS- identity were displayed with different emotional expression (happy, angry) in a post-experimental behavioral task. In contrast to a persistent neural and evaluative CS+/CS- differentiation that sustained multiple unreinforced CS presentations, electrodermal differentiation was rapidly extinguished. Current results suggest that MultiCS conditioning provides a promising paradigm for investigating pre-post-learning changes under minimal influences of extinction and overlearning of simple stimulus features. Our data also revealed methodological pitfalls, such as the possibility of occurring artifacts when combining different acquisition systems for central and peripheral psychophysiological measures.
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http://dx.doi.org/10.3389/fnhum.2015.00336DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4460875PMC
June 2015

Cognitive emotion regulation in children: Reappraisal of emotional faces modulates neural source activity in a frontoparietal network.

Dev Cogn Neurosci 2015 Jun 28;13:1-10. Epub 2015 Feb 28.

Institute for Biomagnetism and Biosignalanalysis, University Hospital Münster, Münster, Germany.

Emotion regulation has an important role in child development and psychopathology. Reappraisal as cognitive regulation technique can be used effectively by children. Moreover, an ERP component known to reflect emotional processing called late positive potential (LPP) can be modulated by children using reappraisal and this modulation is also related to children's emotional adjustment. The present study seeks to elucidate the neural generators of such LPP effects. To this end, children aged 8-14 years reappraised emotional faces, while neural activity in an LPP time window was estimated using magnetoencephalography-based source localization. Additionally, neural activity was correlated with two indexes of emotional adjustment and age. Reappraisal reduced activity in the left dorsolateral prefrontal cortex during down-regulation and enhanced activity in the right parietal cortex during up-regulation. Activity in the visual cortex decreased with increasing age, more adaptive emotion regulation and less anxiety. Results demonstrate that reappraisal changed activity within a frontoparietal network in children. Decreasing activity in the visual cortex with increasing age is suggested to reflect neural maturation. A similar decrease with adaptive emotion regulation and less anxiety implies that better emotional adjustment may be associated with an advance in neural maturation.
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http://dx.doi.org/10.1016/j.dcn.2015.01.012DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6989777PMC
June 2015

Abnormal, affect-specific modulatory effects on early auditory processing in schizophrenia: magnetoencephalographic evidence.

Schizophr Res 2015 Feb 10;161(2-3):308-13. Epub 2014 Dec 10.

Department of Psychology, Clinical Psychology and Psychotherapy, University Münster, D-48149 Münster, Germany; Department of Psychology, Clinical Psychology and Psychotherapy, University Kiel, D-24118 Kiel, Germany. Electronic address:

Abnormalities in the perception and identification of emotions have frequently been reported in schizophrenia. Hemodynamic neuroimaging studies found functional abnormalities in cortical and subcortical brain circuits that are involved in normal affective processing, but the temporal dynamics of abnormal emotion processing in schizophrenia remain largely elusive. To investigate this issue, we recorded early auditory evoked field components by means of whole-head magnetoencephalography that were in response to emotion-associated tones in seventeen patients with schizophrenia and in seventeen healthy, matched controls. Forty-two click-like tones (conditioned stimuli; CS) acquired differential emotional meaning through an affective associative learning procedure by pairing each CS three times with either pleasant, unpleasant or neutral auditory scenes. As expected, differential affect-specific modulation in patients vs. controls was evident, starting at the auditory N1m onset latency of approximately 70ms, extending to 230ms. While controls showed the expected enhanced processing of emotion associated CS, patients revealed an inverted pattern with reduced processing of arousal, when compared to neutral stimuli, in the right prefrontal cortex. The present finding suggests impairments in the prioritization of emotionally salient vs. non-salient stimuli in patients with schizophrenia. Dysfunction in higher cognitive processes and behavior in schizophrenia may therefore reflect dysfunction in fundamental, early emotion processing stages.
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http://dx.doi.org/10.1016/j.schres.2014.11.025DOI Listing
February 2015

Rapid plasticity in the prefrontal cortex during affective associative learning.

PLoS One 2014 21;9(10):e110720. Epub 2014 Oct 21.

Institute for Biomagnetism and Biosignalanalysis, University Hospital Münster, Münster, Germany; Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster, Münster, Germany.

MultiCS conditioning is an affective associative learning paradigm, in which affective categories consist of many similar and complex stimuli. Comparing visual processing before and after learning, recent MultiCS conditioning studies using time-sensitive magnetoencephalography (MEG) revealed enhanced activation of prefrontal cortex (PFC) regions towards emotionally paired versus neutral stimuli already during short-latency processing stages (i.e., 50 to 80 ms after stimulus onset). The present study aimed at showing that this rapid differential activation develops as a function of the acquisition and not the extinction of the emotional meaning associated with affectively paired stimuli. MEG data of a MultiCS conditioning study were analyzed with respect to rapid changes in PFC activation towards aversively (electric shock) paired and unpaired faces that occurred during the learning of stimulus-reinforcer contingencies. Analyses revealed an increased PFC activation towards paired stimuli during 50 to 80 ms already during the acquisition of contingencies, which emerged after a single pairing with the electric shock. Corresponding changes in stimulus valence could be observed in ratings of hedonic valence, although participants did not seem to be aware of contingencies. These results suggest rapid formation and access of emotional stimulus meaning in the PFC as well as a great capacity for adaptive and highly resolving learning in the brain under challenging circumstances.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0110720PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4204938PMC
December 2015

Inhibitory repetitive transcranial magnetic stimulation (rTMS) of the dorsolateral prefrontal cortex modulates early affective processing.

Neuroimage 2014 Nov 12;101:193-203. Epub 2014 Jul 12.

Institute for Biomagnetism and Biosignalanalysis, University Hospital Muenster, D-48149 Muenster, Germany. Electronic address:

The dorsolateral prefrontal cortex (dlPFC) has often been suggested as a key modulator of emotional stimulus appraisal and regulation. Therefore, in clinical trials, it is one of the most frequently targeted regions for non-invasive brain stimulation such as repetitive transcranial magnetic stimulation (rTMS). In spite of various encouraging reports that demonstrate beneficial effects of rTMS in anxiety disorders, psychophysiological studies exploring the underlying neural mechanisms are sparse. Here we investigated how inhibitory rTMS influences early affective processing when applied over the right dlPFC. Before and after rTMS or sham stimulation, subjects viewed faces with fearful or neutral expressions while whole-head magnetoencephalography (MEG) was recorded. Due to the disrupted functioning of the right dlPFC, visual processing in bilateral parietal, temporal, and occipital areas was amplified starting at around 90 ms after stimulus onset. Moreover, increased fear-specific activation was found in the right TPJ area in a time-interval between 110 and 170 ms. These neurophysiological effects were reflected in slowed reaction times for fearful, but not for neutral faces in a facial expression identification task while there was no such effect on a gender discrimination control task. Our study confirms the specific and important role of the dlPFC in regulation of early emotional attention and encourages future clinical research to use minimal invasive methods such as transcranial magnetic (TMS) or direct current stimulation (tDCS).
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http://dx.doi.org/10.1016/j.neuroimage.2014.07.003DOI Listing
November 2014

All in its proper time: monitoring the emergence of a memory bias for novel, arousing-negative words in individuals with high and low trait anxiety.

PLoS One 2014 2;9(6):e98339. Epub 2014 Jun 2.

Institute for Biomagnetism and Biosignalanalysis, University Hospital Münster, Münster, Germany.

The well-established memory bias for arousing-negative stimuli seems to be enhanced in high trait-anxious persons and persons suffering from anxiety disorders. We monitored the emergence and development of such a bias during and after learning, in high and low trait anxious participants. A word-learning paradigm was applied, consisting of spoken pseudowords paired either with arousing-negative or neutral pictures. Learning performance during training evidenced a short-lived advantage for arousing-negative associated words, which was not present at the end of training. Cued recall and valence ratings revealed a memory bias for pseudowords that had been paired with arousing-negative pictures, immediately after learning and two weeks later. This held even for items that were not explicitly remembered. High anxious individuals evidenced a stronger memory bias in the cued-recall test, and their ratings were also more negative overall compared to low anxious persons. Both effects were evident, even when explicit recall was controlled for. Regarding the memory bias in anxiety prone persons, explicit memory seems to play a more crucial role than implicit memory. The study stresses the need for several time points of bias measurement during the course of learning and retrieval, as well as the employment of different measures for learning success.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0098339PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4041778PMC
January 2015

Evidence for rapid prefrontal emotional evaluation from visual evoked responses to conditioned gratings.

Biol Psychol 2014 May 31;99:125-36. Epub 2014 Mar 31.

Institute for Biomagnetism and Biosignalanalysis, University of Münster, Germany.

The human brain's ability to rapidly identify emotional stimuli is subject of ongoing debate. The 'standard hypothesis' postulates a fast but coarse screening of the stimulus valence in subcortical regions, the amygdala in particular, followed by a precise, cortically driven analysis. Recent electrophysiological studies reported differential effects of conditioned faces in prefrontal regions as early as 60-80 ms after target onset, suggesting considerably faster cortical processing than traditionally assumed. Evidence for rapid prefrontal evaluation was provided specifically for complex and evolutionarily significant stimuli, i.e. faces. Here we used simple gratings in a conditioning paradigm, testing the generalization of these results. Event-related potentials and source reconstruction identified rapid (60-80 ms) enhanced processing of affectively conditioned gratings in occipital as well as prefrontal areas. Our results support the assumption of a general fast feed-forward sweep of information, partially activating an interconnected network of affective processing encompassing sensory, subcortical and prefrontal cortex regions.
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http://dx.doi.org/10.1016/j.biopsycho.2014.03.010DOI Listing
May 2014

A large N400 but no BOLD effect--comparing source activations of semantic priming in simultaneous EEG-fMRI.

PLoS One 2013 31;8(12):e84029. Epub 2013 Dec 31.

Institute for Biomagnetism and Biosignalanalysis, Medical Faculty, Westfälische Wilhelms-Universität, Münster, Germany.

Numerous studies have reported neurophysiological effects of semantic priming in electroencephalography (EEG) and in functional magnetic resonance imaging (fMRI). Because of differing methodological constraints, the comparability of the observed effects remains unclear. To directly compare EEG and fMRI effects and neural sources of semantic priming, we conducted a semantic word-picture priming experiment while measuring EEG and fMRI simultaneously. The visually presented primes were pseudowords, words unrelated to the target, semantically related words and the identical names of the target. Distributed source analysis of the event-related potentials (ERPs) successfully revealed a large effect of semantic prime-target relatedness (the N400 effect), which was driven by activations in a left-temporal source region. However, no significantly differing activations between priming conditions were found in the fMRI data. Our results support the notion that, for joint interpretations of existing EEG and fMRI studies of semantic priming, we need to fully appreciate the respective methodological limitations. Second, they show that simultaneous EEG-fMRI, including ERP source localization, is a feasible and promising methodological advancement for the investigation of higher-cognitive processes. Third, they substantiate the finding that, compared to fMRI, ERPs are often more sensitive to subtle cognitive effects.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0084029PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3877131PMC
September 2014