Fig. 11.

Polar plots illustrating the shift in preferred directions for HD cells in the HPC and CTX groups during the 90° cue card rotation sessions. A value of 90° corresponds to an equivalent shift of the preferred direction of a cell, and a 0° shift indicates an absence of cue control by the white card. In both groups of animals, most HD cells exhibited a change in preferred direction that followed the angular rotation of the novel cue. This result occurred in the first set of cue-rotation sessions after the 4 hr delay (insert-cue vs rotate-cue) and when the cue card was returned to its initial position a few minutes later (rotate-cue vs return-cue sessions). These data indicate that the novel environmental cue was able to rapidly establish control over the preferred directions of HD cells in the lesioned animals.