Fig. 4

Learned fear-related behaviour in CamKIIa-Cre XRCC1 KO mice. A Cued Pavlovian fear conditioning. The line plots show the fear response (indexed by percent time freezing) acquired to three successive presentations of the conditioned stimulus (CS) (tone) followed by the unconditioned stimulus (US) (foot shock) for male and female animals. The bar plots depict the expression of conditioned fear towards the context (contextual fear expression) during the context test and the expression of auditory-cued conditioned fear during the tone-CS test (CS-cued fear expression) as measured by percentage time freezing. N = 5 Con and 6 KO males, 5 Con and 5 KO females. Shown are all individual values, means ± SEM. ****p < 0.001 based on repeated-measures ANOVA, *p < 0.05 based on independent Student’s two-tailed t-test. B Acquisition, expression and extinction of contextual fear. The line plots show percent time freezing acquired following three successive presentations of foot shocks (unconditioned stimulus, US). The bar plots represent percent time freezing during the fear expression (day 2) and extinction (day 3 and day 4) phases. N = 10 Con and 7 KO males, 9 Con and 5 KO females. Shown are all individual values, means ± SEM. *p < 0.05, based on post hoc comparisons following repeated-measures ANOVA