PCPA-PRODUCED EFFECTS ON BEHAVIOR IN RATS
503
HIPPOCAMRaL
LESION
Neocortical
lesion
nil
UNOPERATED
controls
Groom
Fig. I. The mean preoperative and postoperative frequencies of locomotion, rearing
(Rear), and grooming (Groom) for groups of animals with hippocampal lesions and neocorti-
cal lesions and for operated controls. The shaded bars represent animals treated with PCPA
before surgery. Open bars are those treated with saline.
age in the first week after surgery (0.02 > P > 0.002), but partially
recovered during the second postoperative week. The animals with hip-
pocampal damage still reared less than those with neocortical damage in
the second week following surgery (0.05 > P > 0.025). Animals with
hippocampal lesions pretreated with saline reared less than they had
preoperatively (P < 0.02), but those pretreated with PCPA returned to
preoperative levels. During the second week the PCPA-treated intact
control animals reared less than similar animals that received saline
treatment (P < 0.05). All animals with hippocampal damage, as well as
animals with only neocortical damage and PCPA treatment, showed re-
duced amounts of grooming compared to their preoperative levels, the
grooming of controls (P < 0.05), and their saline-treated counterparts (P
< 0.038).
Both groups of animals with hippocampal damage had deficits in the
passive avoidance task. They continued to approach the water on more
trials than did other groups of animals and entered the shock compart-
ment with shorter latencies than intact animals by the second shock trial
(0.02 > P > 0.002) and with shorter latencies than animals with neocorti-
cal damage by the third shock trial (P < 0.02) (see Fig. 2).