Figure 1.

Timolol injections in the prelimbic cortex. Latency to make the correct response over the last training trial and the retention trials. Groups were treated 5 min or 2 h after training with timolol or saline. The retention was 48 h later. The Tim-2 h group is significantly different from the sal-2 h (*P < 0.01) and from the Tim-5 min group ( P < 0.01) at the retention test. The performances at the first test trial for the Tim-2 h group were significantly different from both the last acquisition trial (♦P < 0.01) and the second test trial (*P < 0.01), showing an amnesic effect and the ability to relearn the task, respectively.