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Chapter 238May et al., 2015). Therefore, we also aimed to explore whether the link between autistic trait levels and the attentional bias towards angry faces would depend on simultaneously heightened social anxiety trait levels (i.e., a moderation effect) in our healthy sample.MethodParticipantsWe tested 104 participants (75 female) with a mean age of 31.4 years (SD = 14.5, Range: 17 -71) and the majority (n = 95) being right-handed. All participants reported to have no prior or current psychological or neural disorder and performed the experiment either in English (n = 14) or in Dutch (n = 90). Data was collected in three different settings in the Netherlands: the primate park %u2018Apenheul%u2018 in Apeldoorn (n = 30), the science festival %u2018Night of Discoveries%u2019 in Leiden (n = 22) and a laboratory at Leiden University (n = 52). One participant at the primate park and one participant at the science festival had incomplete task data and were disregarded from the analysis (N = 102). Sample characteristics for each location can be found in Table S1 in Online Resource 1. The total sample size was not predetermined as we could not predict the motivation of the primate park/science festival to participate in our study. Yet, the sample size for the laboratory setting was matched to the public settings to balance our sample. All participants provided informed consent prior to participation and there was no monetary reward in either setting but student participants could receive one course credit. The study was conducted in accordance with the Declaration of Helsinki and received approval by the local ethics committee of the Faculty of Social and Behavioural Sciences at Leiden University.Stimuli and TaskTo create our facial emotional expression stimuli, six identities (three female) displaying acted angry, happy, sad, fearful and neutral expressions were chosen from the NimStim database (Tottenham et al., 2009). The face (including the neck) of each stimulus was cut out and the remainder replaced by a grey background (RGB: 145, 145,145), matching the colour of the task background. In order to ensure that observed effects in the dot-probe task were likely to not be caused by systematic differences in low-level features between emotion categories (e.g., de Cesarei & Codispoti, 2013), we employed the Protosc toolbox (Stuit et al., 2021) to