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Chapter 5136was no direct monetary reimbursement for participation. Yet, all participants could enter a lottery (10% chance of winning) to either receive a 10%u20ac vouchers for an online store in the EU or to donate 10%u20ac to %u2018Give Well%u2019 charity (https://www.givewell.org/). Leiden university students could additionally receive 2 course credits. All participants provided informed consent prior to participation. The study was conducted according to the Declaration of Helsinki and the protocol was approval by the local ethics committee of the Faculty of Social and Behavioural Sciences at Leiden University (2020-12-18-M.E. Kret-V1-2834).StimuliColor videos of 5 male and 5 female individuals, showing spontaneous facial expressions of anger, happiness, fear, sadness and neutral in full frontal view, were selected from a previous standardization (Folz et al., 2023) of the FEEDTUM stimulus database (Wallhoff et al., 2006). All videos had a length of 2s (500ms neutral expression followed by 1500ms expression of the respective category) and a gray background. The size of the videos was automatically adjusted to the participants viewport size (4: 3 ratio). All participant viewed all 50 videos once in a random order. ProcedureThe experiment was performed on the online experiment platform Gorilla (AnwylIrvine et al., 2020) (https://gorilla.sc/). Participants were instructed to complete it on a PC screen in a quiet room, without any disturbances. As first part of the experiment, participants performed an emotion recognition task. Each trial started with a central fixation cross for 1s. Afterwards, a facial expression video (see Stimuli section) was presented in the centre of the screen for 2s and followed by a 100ms blank screen. On the next screen, participants chose a label for the displayed expression (%u2018Which type of expression was displayed by the person in the video?%u2019) out of the 5 potential categories (angry/happy/sad/fearful/neutral). They additionally rated the confidence in their decision (%u2018How confident are you about your decision?%u2019) on a visual analogue scale from %u201cnot confident at all%u2019 to %u2018very confident%u2019. Integer values ranged from 0-100 but were not visible to the participant. As last rating on the same screen, participant indicated the perceived emotional intensity of the expression (%u2018How emotionally intense was the expression displayed in the video?%u2019) on a visual analogue scale from %u2018not intense at all%u2019 to %u2018very intense%u2019. Integer values again ranged from 0-100 but were not visible to the participant. Participants could move on to the next trial in a self-paced manner once all three questions had been answered. After the emotion