Effects of septal lesions on the discrimination of fixed-ratio performance

Rats with septal lesions and control rats were required to press the center lever of a three lever operant chamber a fixed number of times before activating the side levers. If the rat pressed the center lever 32 times, then a response on the right lever was correct and food was delivered. If the rat pressed 2, 4, 8, or 16 times on the center lever, then a response on the left lever was correct. Both groups were able to discriminate between long and short fixed-ratio schedules. As expected, more errors were made as the discrimination became more difficult. Septal rats, however, were unable to discriminate as well as control rats. These data suggest that septal lesions interfere with rats' ability to monitor response-produced proprioceptive stimuli.