Fig. 4.

Reducing fear before immediate extinction. (A) Freezing behavior on the conditioning day. Data are 1-min averages for the periods before (baseline, BL) and after a single tone–shock conditioning trial. (B) Freezing behavior during the extinction session in a novel context, which occurred either 15 min (IMMED) or 24 h (DELAY) after conditioning. Control rats were exposed to the context but did not receive CS presentations during extinction (NO-EXT). (C) Freezing behavior during the retention test 48 h after conditioning; data from the retention test were normalized as in Fig. 1D. All data are means ± SEM. ∗, P < 0.005.