To compare direct and indirect indices of attention we used the ANTI-V paradigm (Roca et al., 2011), which includes a primary task (providing independent measures of phasic alertness, orienting, and executive control) and a secondary task (providing direct measures of vigilance). Fifty-four students participated in the experiment. Accuracy in the primary task was at ceiling, while the pattern of response speeds displayed the expected effects related to phasic alertness, orienting, and executive control. An unexpected correlation between phasic alertness and executive control speed scores was also obtained. As regards the secondary task, both accuracy and speed scores were obtained, allowing us to discover a moderate speed-accuracy trade-off between the two tasks: higher accuracy in the secondary go/no go task was associated with the slowing down of speed in the primary yes/no task. Averaging over various conditions of the primary task (i.e., independent of alerting tone presence, cue validity, and flanker congruency) a strong correlation was obtained between response speeds in primary and secondary tasks. However, CFQ scores (a self-report individual measure of everyday failures of attention) did not correlate with overall speed, but with specific aspects of performance related to phasic alertness and vigilance.
