Changes in open-field behaviors following septal lesions in rats

Sixteen rats were tested for 10 min in an open field on postoperative Days 6--7, 11--12, 19--20, and 38--39, under two conditions of illumination. Septal lesions produced alterations in activity, rearing, and grooming that changed over the repeated tests. Septal rats initially had low activity scores that increased over testing to a level higher than that of controls, low rearing behavior that increased over sessions but always remained below control levels, and low grooming scores that became equivalent to controls by postoperative Days 38--39. These findings indicated that repeated testing given only postoperatively in an open field resulted in hyperactivity, decreased rearing, but no differential effect in grooming. The time course of change in these three behaviors was not identical.