Comparison of the septal lesion effects on visual and spatial discriminations in rats.

Postoperative performance in acquisition and reversal learning of septal rats was investigated and compared with control rats in three experiments. Experiment I involved a simultaneous black-white discrimination task. The number of errors in normal and septal rats was similar in acquisition and reversal learning. Both septal and normal rats manifested directional response sets. Experiment II examined a position habit discrimination. Acquisition was similar in septal and normal rats, while reversal learning was impaired in septal rats. Experiment III, which investigated a position habit discrimination with available irrelevant visual stimuli indicated that both acquisition and reversal learning were impaired in operated animals. Results suggested that septal rats utilize response produced cues to control their behavior, but the enhanced orienting response to the visual stimuli interferes with the proprioceptive stimuli.