Fig. 2.

Fear memory deficits in Rap1b cKO but not in Rap1a cKO mice. a Schematic diagram of tone-fear conditioning in the present study. In 1st day, mice were subjected to 4 times CS without US for habituation and were subsequently 3 times CS-US paired for fear acquisition in context A. 24 h later, fear memory test was conducted by placing mice in context B. b No difference of freezing response during habituation, fear conditioning and test between Rap1a^f/f and Rap1a cKO mice. n = 14–15 mice per group. c Impaired fear memory expression in Rap1b cKO mice, compared with Rap1b^f/f mice. n = 12 mice per group. Data are presented as mean ± SEM; **p < 0.01