Fig. 2

HCAR1-deficient mice exhibit altered social behavior. 3-chamber social test for social behavior: a Representative images showing subject mouse movement from social novelty phase of the test (3^rd phase). b-e Quantitative behavioral measure for sociability phase of the test (2^nd phase); 1^st latency to enter (b) and the number of entries (c) in the interaction zones and the sociability did not show any changes between HCAR1 KO and WT mice. However, KO mice spent less time in the chambers with novel mice or the chamber with novel object (d) indicating lower curiosity level in KO animals. f-i Quantitative behavioral measure for social novelty phase of the test (3^rd phase); 1^st latency to enter (f) and the resting time (h) in the interaction zones in the social novelty phase of the test did not show any changes between HCAR1 KO and WT mice. However, KO mice spent significantly more time in the interaction zone with the familiar mice (g) and had an overall lower social novelty score (i). j-k Total time that mice spent rotating clock or counter clockwise (j) and total number of clock or counter clockwise rotations (k) in the whole 3 phases of the test indicate that KO mice exhibit a higher rate of repetitive behavior. Data are mean ± s.d. from n = 12 for KO animal and n = 8 for WT animal. Analysis of Variance (ANOVA) was followed by Bonferroni post hoc correction test with * P < 0.05, ** P < 0.01 significance levels