Limitations of the Cognitive Vigilance Increment

This paper contrasts the positive evidence for a cognitive vigilance increment with several unsuccessful attempts at replication and reports three further experiments. Experiment 1 employs six different levels of task complexity involving the use of auditory cues, finding a weak overall decrement over time. Experiment 2 obtains similar results using the original simple and complex tasks in conditions of cuing. Experiment 3 compares three uncued conditions, finding a slight improvement in response times on the most complex task. Reviewing the evidence suggests three groups of reasons for nonreplication: differences in tasks and presentation variables, possible sex differences, and the presence of cue tones. Making allowance for these variables, it is concluded that fixed-range tasks produce an increment whereas variable-range tasks do not, although all the cognitive versions are relatively resistant to decrement.