The Relationship Between Social Anxiety and Anxious Thinking Styles

A 24-item self-report scale assessing social anxiety symptoms over the past 7 days (Consbruch, Stangier & Heidenreich, 2016; Liebowitz, 1987). Possible scores range from 0 (minimum) to 144 (maximum), with higher scores reflecting higher levels of social anxiety (i.e. worse outcomes). The primary outcome measure is change in score on the LSAS-SR from baseline to follow-up.

A 24-item self-report scale assessing social anxiety symptoms over the past 7 days (Consbruch, Stangier & Heidenreich, 2016; Liebowitz, 1987). Possible scores range from 0 (minimum) to 144 (maximum), with higher scores reflecting higher levels of social anxiety (i.e. worse outcomes).

A 22-item self-report scale used for screening different levels of social anxiety (Turner et al., 1989; Fydrich, 2016). Possible scores range from 0 (minimum) to 132 (maximum), with higher scores reflecting higher levels of social anxiety (i.e. worse outcomes).

A 21-item self-report questionnaire assessing symptoms of depression, stress and anxiety (7 items per subscale) over the past week (Lovibond & Lovibond, 1995; Nilges & Essau, 2015). Possible scores on each subscale range from 0 (minimum) to 21 (maximum), with higher scores reflecting higher levels of symptoms (i.e. worse outcomes).

A 12-item self-report scale used to assess fear of being negatively evaluated by others in social situations (Leary, 1983; Reichenberger, Schwarz, König, Wilhelm, .. & Blechert, 2016). Possible scores range from 12 (minimum) to 60 (maximum), with higher scores reflecting higher levels of fear (i.e. worse outcomes).

The ERT is a 10-item computerized measure of interpretation bias (Salemink & van den Hout, 2010). Four versions are used, applied in a counterbalanced order across participants.

The SRT is used to assess interpretation biases and their neurophysiological correlates via EEG (N400). Participants read ambiguous scenarios (i.e., sentence stems) that are completed by either congruent or incongruent endings, and have to rate how well the endings complete the sentence stems. Participants will be presented with a total of 96 trials, 48 of which are neutral and 48 of which are social anxiety-related. In addition to behavioural responses, the N400 amplitude will be measured via EEG in the 300-450 ms time window post-stimulus onset (i.e., the target word, e.g., Feng et al., 2019; Moser et al., 2008).

The Anagram task is used to investigate stress reactivity towards social-evaluative threats in performance situations (Van Bockstaele et al., 2020). During the Anagram Task, heart rate, heart rate variability, and corrugator activity will be recorded. The state mood ratings (listed below) are used to measure mood response to the task.

Salivary concentrations of cortisol will be collected during both lab assessments. During the first lab assessment, it will be collected once at baseline prior to the administration of the questionnaires. During the second lab assessment, it will be collected four times, at baseline prior to the administration of the questionnaires, pre-Anagram Task, post-Anagram task, post-Anagram task+25 min.

Salivary concentrations alpha-amylase will be collected during both lab assessments. During the first lab assessment, it will be collected once at baseline prior to the administration of the questionnaires. During the second lab assessment, it will be collected four times, at baseline prior to the administration of the questionnaires, pre-Anagram Task, post-Anagram task, post-Anagram task+25 min.

Following Moscovitch et al. (2011), resting frontal alpha asymmetry will be recorded using EEG during an 8-minute resting period (in alternating 1-min eyes-open/eyes-closed segments) at both pre- and post-training. In addition, frontal assymetry will be recorded during the SRT, i.e., when presenting the ambiguous stems.

Expectancy effects will be assessed prior to training using the three expectancy items from the Credibility and Expectancy Questionnaire (Borkovec & Mathews, 1988). A total score is made by standardizing (z-transforming) the three items and adding the z-transformed scores together (i.e. no minimum or maximum scores). Higher scores indicate higher expectancy of improvement.

A questionnaire asking for feedback about the CBM/Sham intervention will be used, adapted from Woud et al. (2021). Each individual item is interpreted separately (i.e. no sum score is created).

The short (20-item) version of the Negative Effects Questionnaire (Rozental et al., 2019) will be used to assess potential negative effects and adverse events linked to the study. The scale will be adapted for the purpose of the study with terms like 'therapy' and 'therapist' changed to e.g. 'study' and 'researchers' (as per Blackwell et al., 2022). The number of reported negative effects for each category are summed for reporting purposes.

State affect will be measured repeatedly throughout the assessment sessions (i.e., at baseline, pre-stressor, post-stressor, during and after the recovery phase) using a 7-item scale developed by Becker et al. (2016). This scale includes the following items: "I feel… tense / sad / anxious / confident / relaxed / happy / relieved", with each item being judged via a 5-point Likert scale.