Response perseveration in the hippocampal lesioned rat

Hippocampal lesions were found to affect a rat’s relearning a previously learned correct arm from a new starting position in a T-maze situation. Hippocampal-damaged rats (HIPP group) perseverated turning responses by entering into the opposite arm from the correct one more than did sham-operated rats (SHAM group). This perseveration phenomenon was seen only for HIPP rats that were required to choose between two similar choice arms. When side arms were differentiated by brightness cues, no differences in relearning the correct arm were found between groups. Greater resistance to extinction of the position habit was also found in HIPP rats, but only in the situation with both side arms similar in color.