Prefrontal mediation of emotion regulation in social anxiety disorder during laughter perception

Neural evidence of face processing in social anxiety disorder: A systematic review with meta-analysis

Numerous previous studies have used event-related potentials (ERPs) to examine facial processing deficits in individuals with social anxiety disorder (SAD). However, researchers still need to determine whether the deficits are general or specific and what the dominant factors are behind different cognitive stages. Meta-analysis was performed to quantitatively identify face processing deficits in individuals with SAD. Ninety-seven results in 27 publications involving 1032 subjects were calculated using Hedges' g. The results suggest that the face itself elicits enlarged P1 amplitudes, threat-related facial expressions induce larger P2 amplitudes, and negative facial expressions lead to enhanced P3/LPP amplitudes in SAD individuals compared with controls. That is, there is face perception attentional bias in the early phase (P1), threat attentional bias in the mid-term phase (P2), and negative emotion attentional bias in the late phase (P3/LPP), which can be summarized into a three-phase SAD face processing deficit model. These findings provide an essential theoretical basis for cognitive behavioral therapy and have significant application value for the initial screening, intervention, and treatment of social anxiety.

Neurobiological correlates and attenuated positive social intention attribution during laughter perception associated with degree of autistic traits

Laughter plays an important role in group formation, signaling social belongingness by indicating a positive or negative social intention towards the receiver. In adults without autism, the intention of laughter can be correctly differentiated without further contextual information. In autism spectrum disorder (ASD), however, differences in the perception and interpretation of social cues represent a key characteristic of the disorder. Studies suggest that these differences are associated with hypoactivation and altered connectivity among key nodes of the social perception network. How laughter, as a multimodal nonverbal social cue, is perceived and processed neurobiologically in association with autistic traits has not been assessed previously. We investigated differences in social intention attribution, neurobiological activation, and connectivity during audiovisual laughter perception in association with the degree of autistic traits in adults [N = 31, M_age (SD) = 30.7 (10.0) years, n_female = 14]. An attenuated tendency to attribute positive social intention to laughter was found with increasing autistic traits. Neurobiologically, autistic trait scores were associated with decreased activation in the right inferior frontal cortex during laughter perception and with attenuated connectivity between the bilateral fusiform face area with bilateral inferior and lateral frontal, superior temporal, mid-cingulate and inferior parietal cortices. Results support hypoactivity and hypoconnectivity during social cue processing with increasing ASD symptoms between socioemotional face processing nodes and higher-order multimodal processing regions related to emotion identification and attribution of social intention. Furthermore, results reflect the importance of specifically including signals of positive social intention in future studies in ASD.

Candidate Biological Markers for Social Anxiety Disorder: A Systematic Review

Social anxiety disorder (SAD) is a common psychiatric condition associated with a high risk of psychiatric comorbidity and impaired social/occupational functioning when not promptly treated. The identification of biological markers may facilitate the diagnostic process, leading to an early and proper treatment. Our aim was to systematically review the available literature about potential biomarkers for SAD. A search in the main online repositories (PubMed, ISI Web of Knowledge, PsychInfo, etc.) was performed. Of the 662 records screened, 61 were included. Results concerning cortisol, neuropeptides and inflammatory/immunological/neurotrophic markers remain inconsistent. Preliminary evidence emerged about the role of chromosome 16 and the endomannosidase gene, as well as of epigenetic factors, in increasing vulnerability to SAD. Neuroimaging findings revealed an altered connectivity of different cerebral areas in SAD patients and amygdala activation under social threat. Some parameters such as salivary alpha amylase levels, changes in antioxidant defenses, increased gaze avoidance and QT dispersion seem to be associated with SAD and may represent promising biomarkers of this condition. However, the preliminary positive correlations have been poorly replicated. Further studies on larger samples and investigating the same biomarkers are needed to identify more specific biological markers for SAD.

A systematic review of the literature on interpretation bias and its physiological correlates

An important, yet under-explored area of interpretation bias research concerns the examination of potential physiological correlates and sequalae of this bias. Developing a better understanding of the physiological processes that underpin interpretation biases will extend current theoretical frameworks underlying interpretation bias, as well as optimising the efficacy of cognitive bias modification for interpretation (CBM-I) interventions aimed at improving symptoms of emotional disorders. To this end, systematic searches were conducted across the Web of Science, PsycInfo and Pubmed databases to identify physiological markers of interpretation bias. In addition, grey literature database searches were conducted to compliment peer-reviewed research and to counter publication bias. From a combined initial total of 898 records, 15 studies were included in qualitative synthesis (1 of which obtained from the grey literature). Eligible studies were assessed using a quality assessment tool adapted from the Quality Checklist for Healthcare Intervention Studies. The searches revealed seven psychophysiological markers of interpretation bias, namely event-related potentials, heart rate and heart rate variability, respiratory sinus arrythmia, skin conductance response, pupillometry, and electromyography. The respective theoretical and practical implications of the research are discussed, followed by recommendations for future research.

ENIGMA-anxiety working group: Rationale for and organization of large-scale neuroimaging studies of anxiety disorders

Anxiety disorders are highly prevalent and disabling but seem particularly tractable to investigation with translational neuroscience methodologies. Neuroimaging has informed our understanding of the neurobiology of anxiety disorders, but research has been limited by small sample sizes and low statistical power, as well as heterogenous imaging methodology. The ENIGMA-Anxiety Working Group has brought together researchers from around the world, in a harmonized and coordinated effort to address these challenges and generate more robust and reproducible findings. This paper elaborates on the concepts and methods informing the work of the working group to date, and describes the initial approach of the four subgroups studying generalized anxiety disorder, panic disorder, social anxiety disorder, and specific phobia. At present, the ENIGMA-Anxiety database contains information about more than 100 unique samples, from 16 countries and 59 institutes. Future directions include examining additional imaging modalities, integrating imaging and genetic data, and collaborating with other ENIGMA working groups. The ENIGMA consortium creates synergy at the intersection of global mental health and clinical neuroscience, and the ENIGMA-Anxiety Working Group extends the promise of this approach to neuroimaging research on anxiety disorders.

Frequency-Specific Alterations in Brain Function in Patients with Primary Dysmenorrhea

OBJECTIVE

Recent neuroimaging studies have found that brain function is abnormal in primary dysmenorrhea (PDM). The present study aimed to explore frequency-specific brain alterations and their occurrence in the PDM.

METHODS

Forty-seven patients with PDM and 36 matched healthy controls were enrolled in the study and underwent resting-state functional magnetic resonance imaging. The alterations in brain function in patients with PDM were assessed using different frequency filter bands (Slow5, Slow4, Slow3, and full low frequency) and functional connectivity density (FCD) approach. The clinical significance of the altered FCD was then explored. Additionally, mediation analysis was employed to detect the altered FCD-mediated clinical relationships in PDM.

RESULTS

Frequency-specific FCD alterations have been observed in patients with PDM, especially in the central executive, default mode, sensorimotor networks, and the hippocampus. The altered full low-frequency FCD in the hippocampus was associated with the duration of disease and pain severity scores. The altered Slow 5 FCD in the second somatosensory area (S2) was associated with the severity of pain in PDM. Furthermore, the FCD in S2 mediated the duration associated with pain symptoms in PDM.

CONCLUSION

The present study identified frequency-specific FCD alterations in PDM and suggested that the S2 area is a potential treatment target for PDM.

Intensified electrical stimulation targeting lateral and medial prefrontal cortices for the treatment of social anxiety disorder: A randomized, double-blind, parallel-group, dose-comparison study

BACKGROUND

Social Anxiety Disorder (SAD) is the most common anxiety disorder while remains largely untreated. Disturbed amygdala-frontal network functions are central to the pathophysiology of SAD, marked by hypoactivity of the lateral prefrontal cortex (PFC), and hypersensitivity of the medial PFC and the amygdala. The objective of this study was to determine whether modulation of the dorsolateral and medial PFC activity with a novel intensified stimulation protocol reduces SAD core symptoms, improves treatment-related variables, and reduces attention bias to threatening stimuli.

METHODS

In this randomized, sham-controlled, double-blind trial, we assessed the efficacy of an intensified stimulation protocol (20 min, twice-daily sessions with 20 min intervals, 5 consecutive days) in two intensities (1 vs 2 mA) compared to sham stimulations. 45 patients with SAD were randomized in three tDCS arms (1-mA, 2-mA, sham). SAD symptoms, treatment-related variables (worries, depressive state, emotion regulation, quality of life), and attention bias to threatening stimuli (dot-probe paradigm) were assessed before and right after the intervention. SAD symptoms were also assessed at 2-month follow-up.

RESULTS

Both 1-mA and 2-mA protocols significantly reduced fear/avoidance symptoms, worries and improved, emotion regulation and quality of life after the intervention compared to the sham group. Improving effect of the 2-mA protocol on avoidance symptoms, worries and depressive state was significantly larger than the 1-mA group. Only the 2-mA protocol reduced attention bias to threat-related stimuli, the avoidance symptom at follow-up, and depressive states, as compared to the sham group.

CONCLUSIONS

Modulation of lateral-medial PFC activity with intensified stimulation can improve cognitive control, motivation and emotion networks in SAD and might thereby result in therapeutic effects. These effects can be larger with 2-mA vs 1-mA intensities, though a linear relationship between intensity and efficacy should not be concluded. Our results need replication in larger trials.

Aggression differentially modulates neural correlates of social intention attribution to benevolent, tickling and taunting laughter: An fMRI study in children and adolescents

Human laughter is a powerful means of communicating social intention, ranging from welcoming and friendly to hostile and ridiculing. To be communicated accurately, the recipient must correctly identify the laugher's underlying social intention. Regular misattribution of the social intention of others has been associated with maladaptive psychosocial development, in particular with aggressive behavior. We investigated the relationship between self-reported aggressive behavior and the neural correlates of social intention attributions to different audiovisual laughter types in 50 healthy children and adolescents (29 female, 10-18 years, M 15.5, SD 2.2) using functional magnetic resonance imaging. Trial-by-trial associations of neural response and behavioral attributions were distinctly modulated by aggression for benevolent versus taunting and tickling laughter. With increasing aggression, hostile misattributions of benevolent laughter were associated with decreased dorsolateral prefrontal and anterior insular cortex activation. In contrast, hostile attributions of taunting and tickling laughter were associated with increased superior frontal, superior temporal, medial prefrontal, supplementary motor, and anterior and mid-cingulate cortex activation. We argue that aggression may be associated with down-regulated emotional saliency of benevolent laughter, whereas up-regulated neural responses to taunting laughter may underlie a heightened sensitivity to hostility or acceptance of taunting behavior in more aggressive individuals.

Interpretation bias in social anxiety: A systematic review and meta-analysis

BACKGROUND

Interpretation bias, which involves interpreting ambiguous social events negatively and catastrophising even mildly negative social events, has been suggested as a key maintenance factor of Social Anxiety Disorder. Although some individual studies and narrative reviews have demonstrated a role for negative interpretation bias in social anxiety (disorder), findings have been mixed. Given the lack of a quantitative synthesis of the evidence, the current systematic review and meta-analysis examined the strength of the relationship between interpretation bias and social anxiety. It also investigated potential moderators of this relationship (i.e., types of measures and stimuli, samples, and study designs).

METHODS

Five databases (PsycINFO, PubMed, Medline, Scopus, and CINAHL) were searched. Of 46 studies identified, 44 were suitable for meta-analysis (N = 3859).

RESULTS

There was a large effect for the relationship between social anxiety and interpretation bias (g = 0.83). Types of measures (subjective versus objective) and stimuli (verbal versus visual) were identified as significant moderators, with subjective measures and verbal stimuli particularly adept at capturing interpretation bias in socially anxious individuals.

LIMITATIONS

The effect sizes displayed significant heterogeneity between studies, which likely reflects some publication bias, and thus, the overall effect size may be inflated.

CONCLUSION

Findings may help to refine clinical models and interventions for Social Anxiety Disorder, which in turn may maximise evidence-based interventions that target negative interpretation bias in this disorder.

Tune in to the right frequency: Theta changes when distancing from emotions elicited by unpleasant images and words

Emotion regulation allows humans to successfully modulate their reactions to life events. Whether regulation strategies may alter brain oscillatory activity and how they are influenced by format and emotional dimensions is still under debate. We investigated oscillatory brain dynamics during the implementation of the strategy of Distancing and during the regulation of the emotions elicited by neutral and unpleasant pictures and, for the first time, words. When implementing the strategy, an early increase in theta band in posterior regions was observed (Effect of Strategy). We interpret this effect as a marker of emotion regulation, and we suggest an integrative framework of the role of theta on regulatory processes. When regulating the emotional impact elicited by stimuli, a decrease in the theta and beta bands in posterior regions for pictures, but not for words, was observed (Effect of Regulation). Behaviorally, the Effect of Regulation was evident for both pictures and words and more pronounced for Valence than for Arousal. These results contribute to better understand the neural and behavioral features of Distancing (both Effect of Strategy and of Regulation), and open up the possibility to clarify which strategy works better to modulate specific stimulus types and emotional dimensions.

Are you laughing at me? Neural correlates of social intent attribution to auditory and visual laughter

Laughter is a multifaceted signal, which can convey social acceptance facilitating social bonding as well as social rejection inflicting social pain. In the current study, we addressed the neural correlates of social intent attribution to auditory or visual laughter within an fMRI study to identify brain areas showing linear increases of activation with social intent ratings. Negative social intent attributions were associated with activation increases within the medial prefrontal cortex/anterior cingulate cortex (mPFC/ACC). Interestingly, negative social intent attributions of auditory laughter were represented more rostral than visual laughter within this area. Our findings corroborate the role of the mPFC/ACC as key node for processing “social pain” with distinct modality‐specific subregions. Other brain areas that showed an increase of activation included bilateral inferior frontal gyrus and right superior/middle temporal gyrus (STG/MTG) for visually presented laughter and bilateral STG for auditory presented laughter with no overlap across modalities. Similarly, positive social intent attributions were linked to hemodynamic responses within the right inferior parietal lobe and right middle frontal gyrus, but there was no overlap of activity for visual and auditory laughter. Our findings demonstrate that social intent attribution to auditory and visual laughter is located in neighboring, but spatially distinct neural structures.

Tuned to voices and faces: Cerebral responses linked to social anxiety

Voices and faces are the most common sources of threat in social anxiety (SA) where the fear of negative evaluation and social exclusion is the central element. SA itself is spectrally distributed among the general population and its clinical manifestation, termed social anxiety disorder, is one of the most common anxiety disorders. While heightened cerebral responses to angry or contemptuous facial or vocal expressions are well documented, it remains unclear if the brain of socially anxious individuals is generally more sensitive to voices and faces. Using functional magnetic resonance imaging, we investigated how SA affects the cerebral processing of voices and faces as compared to various other stimulus types in a study population with greatly varying SA (N = 50, 26 female). While cerebral voice-sensitivity correlated positively with SA in the left temporal voice area (TVA) and the left amygdala, an association of face-sensitivity and SA was observed in the right fusiform face area (FFA) and the face processing area of the right posterior superior temporal sulcus (pSTSFA). These results demonstrate that the increase of cerebral responses associated with social anxiety is not limited to facial or vocal expressions of social threat but that the respective sensory and emotion processing structures are also generally tuned to voices and faces.

Cerebral resting state markers of biased perception in social anxiety

Social anxiety (SA) comprises a multitude of persistent fears around the central element of dreaded negative evaluation and exclusion. This very common anxiety is spectrally distributed among the general population and associated with social perception biases deemed causal in its maintenance. Here, we investigated cerebral resting state markers linking SA and biased social perception. To this end, resting state functional connectivity (RSFC) was assessed as the neurobiological marker in a study population with greatly varying SA using fMRI in the first step of the experiment. One month later the impact of unattended laughter-exemplifying social threat-on a face rating task was evaluated as a measure of biased social perception. Applying a dimensional approach, SA-related cognitive biases tied to the valence, dominance and arousal of the threat signal and their underlying RSFC patterns among central nodes of the cerebral emotion, voice and face processing networks were identified. In particular, the connectivity patterns between the amygdalae and the right temporal voice area met all criteria for a cerebral mediation of the association between SA and the laughter valence-related interpretation bias. Thus, beyond this identification of non-state-dependent cerebral markers of biased perception in SA, this study highlights both a starting point and targets for future research on the causal relationships between cerebral connectivity patterns, SA and biased perception, potentially via neurofeedback methods.

Aggression modulates neural correlates of hostile intention attribution to laughter in children

The tendency to interpret nonverbal social signals as hostile in intention is associated with aggressive responding, poor social functioning and mental illness, and can already be observed in childhood. To investigate the neural correlates of such hostile attributions of social intention, we performed a functional magnetic imaging study in 10-18 year old children and adolescents. Fifty healthy participants rated videos of laughter, which they were told to imagine as being directed towards them, as friendly versus hostile in social intention. Hostile intention ratings were associated with neural response in the right temporal voice area (TVA). Moreover, self-reported trait physical aggression modulated this relationship in both the right TVA and bilateral lingual gyrus, with stronger associations between hostile intention ratings and neural activation in children with higher trait physical aggression scores. Functional connectivity results showed decreased connectivity between the right TVA and left dorsolateral prefrontal cortex with increasing trait physical aggression for making hostile social intention attributions. We conclude that children's social intention attributions are more strongly related to activation of early face and voice-processing regions with increasing trait physical aggression.

Speech Disfluency-dependent Amygdala Activity in Adults Who Stutter: Neuroimaging of Interpersonal Communication in MRI Scanner Environment

Affective states, such as anticipatory anxiety, critically influence speech communication behavior in adults who stutter. However, there is currently little evidence regarding the involvement of the limbic system in speech disfluency during interpersonal communication. We designed this neuroimaging study and experimental procedure to sample neural activity during interpersonal communication between human participants, and to investigate the relationship between the amygdala activity and speech disfluency. Participants were required to engage in live communication with a stranger of the opposite sex in the MRI scanner environment. In the gaze condition, the stranger gazed at the participant without speaking, while in the live conversation condition, the stranger asked questions that the participant was required to answer. The stranger continued to gaze silently at the participant while the participant answered. Adults who stutter reported significantly higher discomfort than fluent controls during the experiment. Activity in the right amygdala, a key anatomical region in the limbic system involved in emotion, was significantly correlated with stuttering occurrences in adults who stutter. Right amygdala activity from pooled data of all participants also showed a significant correlation with discomfort level during the experiment. Activity in the prefrontal cortex, which forms emotion regulation neural circuitry with the amygdala, was decreased in adults who stutter than in fluent controls. This is the first study to demonstrate that amygdala activity during interpersonal communication is involved in disfluent speech in adults who stutter.