Figure 1.

The effect of ketamine (K) on contextual fear conditioning (CFC). 25 mg/kg K induced a state-dependent contextual fear memory. K (25 mg/kg) or saline (S) vehicle were administered intraperitoneally (IP) 30 min before conditioning and Recall 2 (R2), indicated by blue/red arrows, n=6. Data represented by mean±standard error of the mean (SEM) of percentage freezing response normalised to post-unconditioned stimulus (post-US). ***p<0.001, *p<0.05 in Student’s t-test. R1: Recall 1; R3: Recall 3.