Assessment of cFos labeling in the hippocampus and anterior cingulate cortex following recent and remote re-exposure to an unreinforced open field in preadolescent and postadolescent rats.

Spatial tasks are often goal-directed or reward-facilitated confounding the assessment of "pure" recent and remote spatial memories. The current work re-exposed preadolescent and postadolescent male rats to a non-reinforced, free exploration task to investigate cFos patterns within the hippocampus and anterior cingulate cortex (ACC) associated with recent and remote periods. Male rats were exposed to an open field task for one, 30 min session on postnatal day (P) 20, 25, or 50 and re-exposed for 30 min at either a recent (24 hours) or remote (3 weeks) timepoint.