Figure 4.

Experiment 4.1. Effects of atenolol, applied 10 min before the conditioning session on defensive behavior exhibited by rats exposed to a cat odor. The familiarization, the conditioning to the cat odor, and the context sessions were conducted during 3 consecutive days, during which the percentage of approach time, the percentage of hide time, and the head-out time were recorded in 10 min sessions each. Hatched horizontal bars represent the mean and the confidence limits (±95%) for the data obtained during the familiarization session. PBS (n = 9), 10 nmol atenolol (A10; n = 7), and 40 nmol atenolol (A40; n = 7) in the PMd and the A-out group (n = 15) were microinjected (0.2 μl) 10 min before the conditioning to the cat odor. *p < 0.05 compared with PBS group.