Fixed-duration shock treatment: Pre- and posttreatment stimulation, activity, and skin resistance as predictors of escape performance

Abstract

Movement rates and skin resistance levels were recorded during a series of fIxed-duration treatment shocks (ST), some coupled with a feedback stimulus (FB), and others presented in the context of procedures that offset the effects of FB on ST. These measures also were recorded in an escape-training test situation, along with escape latencies. Major fmdings were (1) parallel decreases in both movement and skin resistance levels in response to ST, that (2) developed over blocks of treatment shocks, and that (3) were followed by attenuated movement in the test setting. These changes, in turn, (4) were associated with impaired test escape performances. However, (5) when a FB procedure was introduced that offset the development ofthese movement and skin resistance changes during ST, subjects moved and escaped the same during testing as non-ST controls. Finally, (6) two procedures designed to nullify the effects of FB, introduction (in various ways) of a brief shock following the FB event (Experiment 1) and repetitious pre-ST exposure to the FB stimulus (Experiment 2), were accompanied by reinstatement of attenuated movement rates and skin resistance levels during ST and of impaired test behaviors. These outcomes were consistent with current fear interpretations of inescapable shocktreatment effects, and with condition-inhibition but not disruption or dishabituation (antihypogesic) interpretations of FB effects.