Effects of Sensitivity, Criterion Shifts, and Subjective Confidence on the Development of Automaticity in Airline Luggage Screening

We examined the effect of cognitive factors on the development of automaticity in a complex task. Participants (n = 24) performed a luggage screening task where we manipulated stimulus mapping (consistent vs. varied), frame size (small vs. large), memory set size (1 vs. 4) and time constraint, and examined their effects on participants’ sensitivities, criterion shifts and confidence. Results revealed that the highest cognitive advantage in terms of high sensitivities and minimal deviations from optimal beta was afforded by the combination of small memory sets and consistent mapping of targets, after extended practice. Varied mapping of stimuli under high memory loads exerted a negative effect on sensitivities and induced a greater shift from optimal beta. The concurrence of high memory loads with varied mapping also led to decreases in confidence that hindered automatic detection of targets. The results have implications for training individuals to develop appropriate decision-making strategies in complex vigilance tasks.