Examples of hippocampal “splitter” cells that fire when the rat is traversing the central stem of a T-maze while performing a spatial alternation task. On the left and middle panels of each example, the paths taken by the animals are plotted in light gray: (left-turn trials) and dark-gray (right-turn trials) and the location of the rat when individual spikes occurred is indicated separately for left-turn trials (blue dots), and right-turn trials (red dots). In the right panel, the mean firing rate of the cell for each of four sequential sectors of the central stem, adjusted for variations in the animal's speed, lateral position, and head direction, is shown separately for left-turn trials (blue) and right-turn trials (red). A. A cell that fired almost exclusively on left-turn trials as the rat traversed later sectors of the stem. B. A cell that fired almost exclusively on right-turn trials as the rat traversed early sectors of the stem. ** p<.01, *** p<.001.