Extended Data Fig. 4: Task controls and behavioural performances.
From: Frontal neurons driving competitive behaviour and ecology of social groups
a, A 3-D representation of the custom-designed arena with automated gates and food dispenser (Extended Data Fig. 1) but with dividers now placed in the staging area (SA) for the pre-trial partitioning control. b, Spatial trajectories of all animals across all trials within one representative session with SA dividers. Squares indicate the instantaneous position of the animals when the first mouse reaches the reward zone (RZ). c, Higher ranked animals displayed greater success when compared to their subordinates both in trials with and without SA partitioning (rs=0.419, p=9.1x10-7 for divider trials; rs=0.593, p=1.22x10-16 for open trials; Spearman correlation). The presence of dividers, however, significantly affected the effect that the animals’ rank had on their competitive success (*Fdivider*rank(6,223)=2.34, p=0.032; two-way ANOVA). N=16 sessions across n=3 unique groups of 7 mice. Shaded areas denote mean±95%CI. d, Left, For trials with SA partitioning, the dominant animals were more likely to be the first to reach the reward zone compared to subordinate partners (*rs=-0.702, p=6.74x10-18; Spearman correlation). However, there was no relation between dominance rank and leaving the staging area (rs=-0.095, p=0.12). Right, In trials without SA partitioning, the dominant animals were more likely to be the first to exit the staging area (*rs=-0.43, p=2.41x10-6) and reach the reward zone (*rs=-0.742, p=8.15x10-21). There was a significant interaction between the animal’s absolute dominance in their respective hierarchies and the presence of dividers in the staging area (***Fdivider*rank(6,447)=2.58, p=0.018; two-way ANOVA), together suggesting that the animals took into account information about the relative ranks of the other animals both prior to and after trial start during competition. N=16 sessions across n=3 unique groups of 7 mice. e, Graphic depicting a dynamic non-social context control where inanimate totems were pulled from the staging area until the entrance point of the reward zone using an automated retractor while one mouse foraged for a food pellet (see Methods). f, Spatial trajectories of all moving totems and mouse across all trials within one representative session. Squares indicate the instantaneous position of the animals and totems when the mouse reached the entrance point. g, The mice and moving totems reached the entrance point at approximately the same time (n=54 sessions across n=14 mice; F(3,197)=0.27, p=0.85; one-way ANOVA). h, There were no main effects of hierarchical rank (Frank(6,107)=0.89, p=0.50; two-way RM-ANOVA) or interaction effects of rank and totem movement (Frank*totemtype(6,107)=0.68, p=0.67; two-way RM-ANOVA) on the animals’ latency to reach reward during the totem trials; together suggesting that presence of the moving totems did not influence the animals’ behaviour. There was no difference in latency to reach the reward zone based on absolute dominance rank when the animals foraged alone. N=54 total sessions across n=2 mice per rank. Error bars denote mean±95%CI. i, To evaluate whether the more dominant animals were stronger or were more perseverant, the animals were required to move a mass of variable weight at the reward entrance point. There was no significant difference in latency for animals to reach the entrance point between different weighted blockers (F(4,255)=2.16, p=0.07) but did display an expected difference in for the different staging areas (*F(1,255)=35.2, p≈0). There was no interaction between terms describing the weight amount and staging area location (F(4,255)=0.23, p=0.92; Two-way ANOVA). N=26 mice per blocker weight. Error bars denote mean±95%CI. j, There was a significant difference in latency to enter the reward zone based on the weight of the blockers (*F(4,255)=27.9, p≈0), but no difference between staging area locations (F(1,255)=0.08, p=0.78). There was no interaction between terms describing the weight amount and staging area location (F(4,255)=0.25, p=0.91; Two-way ANOVA). N=26 mice per blocker weight. Error bars denote mean±95%CI. k, There was no difference in latency to enter the reward zone based on ranks across any of the weights (F(24,255)=7.9, p=0.32; Two-way ANOVA); suggesting that hierarchical rank did not significantly affect the animals’ strength or perseverance. N=26 mice per blocker weight (n=3,3,4,4,5,3,4 for absolute ranks 1-7, respectively). Error bars denote mean ± s.e.m. Dots represent session averages. Box-plot edges represent 25th/75th percentiles with centre=median and whiskers=1st-99th percentile range.
