Page 92 - Like me, or else... - Michelle Achterberg

Chapter 4
finger. As soon as the participant started the button press, the volume bar started to fill up with a new colored block appearing every 350 ms. After releasing the button, or at maximum intensity (after 3500 ms), the volume bar stopped increasing and stayed on the screen for the remainder of the 5000 ms. Before the start of the next trial, another jittered fixation cross was presented (0 -11550 ms) (Figure 1). The length of the noise blast duration (i.e., length of button press) in milliseconds was used as a measure of imagined aggression.
Figure 1. Example of one trial of the social network aggression task. Social feedback manipulation check
The social feedback manipulation was checked using an exit interview with questions on how much they liked the feedback (‘How much did you like reactions with a thumb up?’, ‘How much did you like reactions with a circle?’, and ‘How much did you like reactions with a thumb down?’). Participants rated the reactions on a 6-point scale, with 1 representing very little and 6 representing very much. In addition, we asked two open questions: ‘what did you think of the game?’, and ‘what did you think of the noises that you could deliver’. None of the participants expressed doubts about the cover story.
To verify whether children differentially evaluated the social feedback conditions (positive, negative, neutral), we analyzed answers to the exit questions with a repeated measures ANOVA. Data from the exit questions were missing for 5 participants. Results (Greenhouse-Geisser corrected) showed a significant main effect of type of feedback on the subjective evaluation of social feedback with a large effect size (F(2, 1002)= 19.16, p<.001, ω2=0.62). Pairwise comparisons showed that participants liked negative feedback (M=2.27, SD=1.18) significantly less than neutral feedback (M=4.14, SD=0.87, p<.001, d= 1.80) and positive feedback (M=5.33, SD=0.88, p<.001, d= 2.94). Participants also liked neutral feedback significantly less than positive feedback (p<.001, d= 1.37).
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