FIG. 3.
Freezing behavior. (A) Upper panel: percentage (%) freezing (±SEM) evoked by the CS− (gray) and CS+ (black) during pre-exposure, Day 2 of training, and extinction. Lower panel: the difference contrast (CS+ minus CS− ± standard error of the difference, SED) for the data shown in the upper panel. (B) Upper panel: % freezing (±SEM) evoked by the CS−1 and CS+1 (left) and CS−5 and CS+5 (right) during extinction (CS−, gray; CS+, black). Lower panel: the difference contrast (±SED) for the freezing data shown in the upper panel. Pre-ex, pre-exposure session. *P < 0.01; **P < 0.001. CS, conditioned stimulus.