Fig. 1.

Experimental protocol. Recordings were made on 2 consecutive days. On the first day, at least two cells were identified and recorded in the familiar environment, shown here as a white cylinder with a black cue. This was followed by a session in a novel environment: a cylinder of the same size but of a different color, and with different cues on its walls. Immediately after removal from the novel environment, the animal was injected with either drug or saline. The gray box indicates the duration of protein synthesis inhibition. We recorded from the animals in both the novel and familiar environments at 1, 6, and 24 h postinjection.