Vigilance and Reduction of Uncertainty

Abstract

Two groups of 20 Ss each received a series of shocks either predictably or unpredictably paired with certain stimuli. Although Ss receiving predictable shocks failed to evidence a group vigilance effect to the stimuli signalling shock, they did report experiencing less anxiety than Ss receiving unpredictable shocks, despite the fact that the stimuli were perceptually difficult to identify. Both groups of Ss rated unexpected shocks as more unpleasant than expected shocks.