Stephan Stevens

Interoceptive sensitivity in anxiety and anxiety disorders: An overview and integration of neurobiological findings

Interoceptive sensitivity, particularly regarding heartbeat, has been suggested to play a pivotal role in the pathogenesis of anxiety and anxiety disorders. This review provides an overview of methods which are frequently used to assess heartbeat perception in clinical studies and summarizes presently available results referring to interoceptive sensitivity with respect to heartbeat in anxiety-related traits (anxiety sensitivity, state/trait anxiety), panic disorder and other anxiety disorders. In addition, recent neurobiological studies of neuronal activation correlates of heartbeat perception using positron emission tomography (PET), functional magnetic resonance imaging (fMRI) or electroencephalographic (EEG) techniques are presented. Finally, possible clinical and therapeutic implications (e.g., beta-blockers, biofeedback therapy, cognitive interventions and interoceptive exposure) of the effects of heartbeat perception on anxiety and the anxiety disorders and the potential use of interoceptive sensitivity as an intermediate phenotype of anxiety disorders in future neurobiological and genetic studies are discussed.

Heartbeat perception in social anxiety before and during speech anticipation

According to current cognitive models of social phobia, individuals with social anxiety create a distorted image of themselves in social situations, relying, at least partially, on interoceptive cues. We investigated differences in heartbeat perception as a proxy of interoception in 48 individuals high and low in social anxiety at baseline and while anticipating a public speech. Results revealed lower error scores for high fearful participants both at baseline and during speech anticipation. Speech anticipation improved heartbeat perception in both groups only marginally. Eight of nine accurate perceivers as determined using a criterion of maximum difference between actual and counted beats were high socially anxious. Higher interoceptive accuracy might increase the risk of misinterpreting physical symptoms as visible signs of anxiety which then trigger negative evaluation by others. Treatment should take into account that in socially anxious individuals perceived physical arousal is likely to be accurate rather than false alarm.

Influence of alcohol on the processing of emotional facial expressions in individuals with social phobia

OBJECTIVES Individuals with social phobia are at an increased risk to develop alcohol problems. However, the mechanism responsible for this association is unclear. It has been suggested that alcohol reduces anxiety by impairing initial appraisal of threatening stimuli. Information that is especially threatening, however, may be resistant to such an effect of alcohol. We tested the influence of alcohol on the appraisal of five emotional facial expressions. METHODS 40 social phobia patients and 40 controls performed a dot probe task, after drinking either alcohol or orange juice. Stimuli were faces with happy, angry, neutral and also two ambiguous expressions that were formed by blending angry or happy faces and neutral faces. Stimuli were presented for either 175 or 600 ms. RESULT Sober patients showed an attentional bias towards angry faces, indicating preferential processing of threat stimuli. Alcohol significantly reduced this bias. Only in sober participants, this attentional bias correlated with measures of social anxiety. In controls, no biases were observed. CONCLUSIONS Alcohol seems to attenuate the impact of threatening social stimuli on social phobia patients, which may negatively reinforce the consumption of alcohol and at least partially explain the heightened comorbidity with alcohol related problems known from epidemiological studies. The dot probe task with short stimulus presentation times seems to provide an adequate method to demonstrate alcohol effects on information processing.

Blood-Injury Phobia With and Without a History of Fainting: Disgust Sensitivity Does Not Explain the Fainting Response

Objective: Individuals diagnosed with blood-injury phobia respond to venipuncture with strong psychophysiological responses. We investigated whether disgust sensitivity contributes to the fainting response and is associated with parasympathetic activation, as suggested by previous research. Methods: Twenty individuals diagnosed with blood-injury phobia (9 with a history of fainting to the sight of blood, 11 without such a fainting history) and 20 healthy controls were compared. Psychophysiological responses and self-report measures of anxiety, disgust, and embarrassment were monitored during rest, a paced breathing task, and venipuncture. In addition, trait disgust sensitivity and blood-injury fears were assessed. Results: Blood-injury phobics reported enhanced anxiety, disgust, and embarrassment during venipuncture. They also experienced heightened arousal, as indicated by heart rate, respiration rate, and minute ventilation. Blood-injury phobics without a fainting history tended toward higher anxiety and disgust scores. There was no evidence for increased parasympathetic activation in either blood-injury phobic subgroup or of an association of disgust and parasympathetic activation. Conclusion: The tendency to faint when exposed to blood-injury stimuli may suffice as a conditioning event leading into phobia, without specific involvement of disgust sensitivity and parasympathetic activation. BIP+ = blood-injury phobia with a history of fainting; BIP− = blood injury phobia without a history of fainting; RSA = respiratory sinus arrhythmia; PSD HR = log-transformed power spectral density of heart rate oscillations (0.15–0.50 Hz); CMTR LV-HR = coherence-corrected magnitude of the transfer function-relating lung volume oscillations to heart rate oscillations at the peak respiratory frequency; BIFQ = blood-injury-fear questionnaire; FEE = Fragebogen zur Erfassung der Ekelempfindlichkeit.

What does the facial dot-probe task tell us about attentional processes in social anxiety? A systematic review.

BACKGROUND/OBJECTIVES Current models of SAD assume that attentional processes play a pivotal role in the etiology and maintenance of social anxiety disorder. Social anxiety is supposedly associated with an attentional bias towards disorder related stimuli such as threatening faces. Using the facial dot probe task in socially anxious individuals has, however, revealed inconsistent findings. METHODS The current systematic review aims at disentangling the heterogeneous findings using effect sizes across results by systematically taking into account potential moderating variables (stimulus type, stimulus duration, situational anxiety, disorder severity). RESULTS Results provide some evidence that socially anxious individuals preferentially allocate their attention towards threat faces compared to non-anxious controls. This bias seems to depend on the type of reference stimulus, stimulus duration and clinical level of social anxiety. Avoidance of threat was neither found at early, nor at later stages of attentional processing. LIMITATIONS Importantly, the results have to be considered in the light of the only few studies available. Given the heterogeneity of results and some methodological restrictions of the studies included, the picture of attentional bias seems to be much less clear than suggested in the recent social anxiety literature. CONCLUSIONS Methodologically, combined measures of dot-probe and eye movement measures might be beneficial to detect overt attentional biases. Importantly, our results show that preferential processing of threat cues might guide early attentional processes in social anxiety, depending however on several contextual and situational factors. Clinically, patients with greater severity of SAD may be more prone to such an attentional bias, thus therapists should take this into account when planning behavioral experiments and exposure therapy.

Eye movement assessment in individuals with social phobia: differential usefulness for varying presentation times?

Visual dot probe tasks are used to examine attentional biases towards threat faces in social phobia. Based on eye movement assessments, short presentation times of stimuli have been proposed to investigate initial attentional processes. However, it remains unclear if eye movements contribute to anxiety related biases as measured in dot probe tasks when presentation times below 200 ms are used. In this study the electrooculogram (EOG) was recorded in a sample of 17 participants with social phobia and 13 controls performing a visual dot probe task in two presentation time conditions. In the 175 ms condition, half of the participants moved their eyes in only 10% of the trials. Significantly more participants moved their eyes in the 600 ms condition and individuals with social phobia directed their gaze more often to the threat faces than to the neutral faces. Eye movement measures were not related to reaction time measures but the number of initial eye movements towards threatening faces correlated with measures of social anxiety. For dot probe paradigms, the additional use of eye movement measures seems to be particularly appropriate for longer presentation times. The dissociation between attentional bias scores as measured with reaction time versus eye movement measures and their relation to different presentation times underlines the need for both measures when conducting visual probe studies.

Blushing propensity in social anxiety disorder: influence of serotonin transporter gene variation.

Blushing is considered to be one of the prime pathophysiological markers of social anxiety disorder, potentially mediated by serotonergic function. Therefore, in the present study 62 patients with social anxiety disorder and 62 age- and sex-matched healthy controls were investigated for the influence of serotonin transporter (5-HTT) gene variation (5-HTTLPR, rs25531) on blushing propensity as measured by the blushing propensity scale (BPS). The less active 5-HTTLPR genotypes were nominally significantly associated with increased blushing propensity in patients with social anxiety disorder as compared to controls with an equidirectional trend for the less active 5-HTTLPR/rs25531 haplotypes. Even when statistically controlled for influence of depression, this association remained significant. In summary, the present pilot study suggests a potential role of functional serotonin transporter gene variation in blushing propensity warranting replication and encouraging genetic analyses of further intermediate phenotypes of social anxiety disorder.

Predicting post-event processing in social anxiety disorder following two prototypical social situations: state variables and dispositional determinants.

This study investigated self-reported state (anxiety, physical symptoms, cognitions, internally focused attention, safety behaviors, social performance) and trait (social anxiety, depressive symptoms, dysfunctional self-consciousness) predictors of post-event processing (PEP) subsequent to two social situations (interaction, speech) in participants with a primary diagnosis of social anxiety disorder (SAD) and healthy controls (HC). The speech triggered significantly more intense PEP, especially in SAD. Regardless of the type of social situation, PEP was best predicted by situational anxiety and dysfunctional cognitions among the state variables. If only trait variables were considered, PEP following both situations was accounted for by trait social anxiety. In addition, dysfunctional self-consciousness contributed to PEP-speech. If state and trait variables were jointly considered, for both situations, situational anxiety and dysfunctional cognitions were confirmed as the most powerful PEP predictors above and beyond trait social anxiety (interaction) and dysfunctional self-consciousness (speech). Hence, PEP as assessed on the day after a social situation seems to be mainly determined by state variables. Trait social anxiety and dysfunctional self-consciousness also significantly contribute to PEP depending on the type of social situation. The present findings support dysfunctional cognitions as a core cognitive mechanism for the maintenance of SAD. Implications for treatment are discussed.

Self-referential and anxiety-relevant information processing in subclinical social anxiety: an fMRI study

The fear of negative evaluation is one of the hallmark features of social anxiety. Behavioral evidence thus far largely supports cognitive models which postulate that information processing biases in the face of socially relevant information are a key factor underlying this widespread phobia. So far only one neuroimaging study has explicitly focused on the fear of negative evaluation in social anxiety where the brain responses of social phobics were compared to healthy participants during the processing of self-referential relative to other-referential criticism, praise or neutral information. Only self-referential criticism led to stronger activations in emotion-relevant regions of the brain, such as the amygdala and medial prefrontal cortices (mPFC), in the social phobics. The objective of the current study was to determine whether these findings could be extended to subclinical social anxiety. In doing so, the specificity of this self-referential bias was also examined by including both social and non-social (physical illness-related) threat information as well as a highly health anxious control group in the experimental paradigm. The fMRI findings indicated that the processing of emotional stimuli was accompanied by activations in the amygdala and the ventral mPFC, while self-referential processing was associated with activity in regions such as the mPFC, posterior cingulate and temporal poles. Despite the validation of the paradigm, the results revealed that the previously reported behavioral and brain biases associated with social phobia could not be unequivocally extended to subclinical social anxiety. The divergence between the findings is explored in detail with reference to paradigm differences and conceptual issues.

The motive to drink due to social anxiety and its relation to hazardous alcohol use

Although studies on social anxiety and alcohol-related problems are numerous, the exact nature of the relationship remains unclear. In the present study, we investigate how the motive to drink due to social anxiety is associated with hazardous alcohol use over and above habitual alcohol use, social anxiety, and alcohol outcome expectancies. We also examine which factors define the motive to drink due to social anxiety and clarify the impact of the type of social situation. Drinking due to social anxiety, habitual alcohol use, and gender, but not social anxiety, were associated with hazardous alcohol use. Social anxiety increased the motive to drink due to social anxiety, but fear of cognitive performance deficits after drinking reduced it. Alcohol was used to reduce anxiety more frequently in situations where intake of alcohol is deemed socially acceptable. These findings suggest that the motive drinking due to social anxiety, not social anxiety per se, is related to hazardous alcohol use. The motive is weakened by the expectation of alcohol-induced cognitive deficits, as well as by the type of social situation in which alcohol is to be used.