Understanding hippocampal activity by using purposeful behavior: Place navigation induces place cell discharge in both task-relevant and task-irrelevant spatial reference frames

Continuous rotation of an arena in a cue-rich room dissociates the stationa ry room-bound information from the rotating arena-bound information. This d isrupted spatial discharge in the majority of place cells from rats trained to collect randomly scattered food. In contrast, most place cell firing pa tterns recorded from rats trained to solve a navigation task on the rotatin g arena were preserved during the rotation. Spatial discharge was preserved in both the task-relevant stationary and the task-irrelevant rotating refe rence frames, but firing was more organized in the task-relevant frame. It is concluded that, (i) the effects of environmental manipulations can be un derstood with confidence only when the rat's purposeful behavior is used to formulate interpretations of the data, and (ii) hippocampal place cell act ivity is organized in multiple overlapping spatial reference frames.