Extended Data Fig. 8: Within-group Averaged Neural Activity at Channel 8 in the rDLPFC after Winning or Losing.
From: Within-group synchronization in the prefrontal cortex associates with intergroup conflict
We compared the within-group averaged neural activity in rDLPFC after the group won or lost the last round. We conducted Bonding (in-group bonding vs. control) × Outcome of last-round T-1 (win(T-1) vs. lose(T-1)) mixed-model ANOVAs on the within-group averaged neural activity of round T. First, we found a significant main effect of Outcome, i.e., stronger neural activity in the rDLPFC during the next-round decision-making phase after the group lost (relative to won) the game, for both the attacker (a, channel 8: F1,82 = 29.791, p = 5.00 × 10−7, η2 = 0.266) and defender (b, channel 8: F1,82 = 26.595, p = 1.71 × 10−6, η2 = 0.245). Moreover, for the attacker group, we found a significant interaction of Bonding and Outcome on within-group averaged rDLPFC activity (channel 8: F1,82 = 13.207, p = 4.85 × 10−4, η2 = 0.139). Outcome-by-Bonding mixed-model ANOVAs (n = 84, 42 three-person groups under no-bonding control and 42 three-person groups under in-group bonding separately for attacker groups and defender groups). Data from two sessions were excluded as attackers in these two sessions did not win any of the 24 rounds. Data are plotted as boxplots for each condition in which horizontal lines indicate median values, boxes indicate 25/75% quartiles, and whiskers indicate the 2.5-97.5% percentile range. Data points outside the range are shown separately as circles. Solid lines start from the mean and reflect the intervals for the Mean ± S.E. ***p < 0.001.
