Cognitive predictors of vigilance

Three studies are reported of individual differences in performance of high event rate vigilance tasks. In each study, measures of attentional resource availability and elementary cognitive components of sustained attention were correlated with vigilance performance. It was predicted that correlates of vigilance should vary with two parameters of the task: the type of target discrimination required (simultaneous or successive) and the type of stimuli used (sensory or symbolic). Speed and accuracy of controlled, resource-demanding visual search predicted overall perceptual sensitivity on three out of four successive tasks used, but only one out of four simultaneous tasks, partially confirming the hypothesis that successive tasks are more strongly resource-limited than simultaneous tasks. Other correlates of overall level vigilance did not appear to vary systematically with task parameters. Few correlates of temporal decrement in perceptual sensitivity were found, possibly for statistical reasons. The data suggest that measures of controlled search may be useful in predicting vigilance on certain real-world tasks, although a substantial part of the variance of vigilance tasks may not be predictable from short cognitive tasks.