| Abstract: | ![]()
Physiological responses were recorded while 9 females (Group P) who Feared spiders and 9 who did not (Group N) viewed “neutral” and spider slides in a delayed, differential conditioning procedure. Two different tones were the conditioned stimuli, and 12 neutral and 12 spider slides the unconditioned stimuli. Each CS was 11 sec long. Only Group P showed differential HR conditioning-anticipatory acceleration to the CS preceding the spider slides (CS+). For both groups, cephalic vasoconstriction was greater to the CS+ than to the CS-. However, with repeated trials Group P's response to the CS+ became more prolonged, so that by the last block of trials contraction persisted until the end of the CS period. Group N's response, on the other hand, continued to be constriction followed by rapid recovery to the prestimulus level. Although significant electrodermal conditioning did not occur, Group P tended to give larger anticipatory SC. responses to the CS+ than to the CS-. There was little evidence of somatic-autonomic coupling on a group basis. When considered along with post-experimental reports, the results indicate that at least some of the cardiovascular components of the defensive response (DR) are conditionable. |
