The effects of lesions to the postsubiculum or the anterior dorsal nucleus of the thalamus on spatial learning in rats.

To investigate the role of the head direction (HD) cell circuit in spatial navigation, rats with bilateral, neurotoxic lesions to the postsubiculum (PoS; Experiment 1) or the anterior dorsal nucleus of the thalamus (ADN; Experiment 2) were compared to sham controls on 2 tasks that could be solved using directional heading. Rats were first trained on a direction problem in a water T maze where they learned to travel either east or west from 2 locations in the experimental room. ADN lesioned rats were impaired relative to sham controls on the first block of 8 trials, but not on the total trials taken to reach criterion.