EFFECTS OF SIGNAL-SHOCK CONTINGENCY PROBABILITY ON GASTRIC LESIONS IN RATS AS A FUNCTION OF SHOCK REGION

Effects of signal-shock contingency probability on stress pathology were studied with 2 regions of electric shock and with (a) only sound signal presentations (NS), (b) unrelated presentations of the signal and tail shock (TS) or foot shock (FS) (NPS), (c) signal presentations all of which were paired with the TS or FS (100PS), or (d) signal presentations, 50% of which were paired with a TS or FS (50PS). Rats in NPS and 50PS groups with TS showed more stress-induced pathology than animals in the 100PS group with TS. However, the 100PS group with FS resulted in greater gastric lesions than NPS, 50PS, or NS group. The interaction between shock region and signal-shock contingency probability plays an important role.