Septal lesions facilitate the shift from conditioned escape to conditioned avoidance behavior in the rat.

Normal rats were given 1000 training trials in a discriminated lever-press avoidance task. Those animals which exhibited consistent escape behavior but minimal avoidance responding were subjected to either septal lesions or control operations. One week later they were retested in the avoidance apparatus for an additional 1000 trials. Rats with large septal lesions exhibited an immediate increase in avoidance performance relative to the control rats. This increase occurred without a concomitant increase in number of lever-press responses. The performance of 3 out of 4 rats with smaller more dorsal septal lesions was unaffected by the surgery.