Abstract
Laboratory-based visual searches provide a powerful tool for revealing the nature of cognitive processes and informing visual searches conducted outside of the lab. However, whereas professional searches, such as baggage screening, military searches, and radiological examinations, are often conducted in high-pressure environments and can contain multiple visual targets, laboratory searches tend to be conducted in emotionally-neutral settings and with only one possible target per display. These discrepancies potentially diminish the benefits of laboratory-based searches and leave important questions unanswered. To better emulate high-pressure search conditions, we presented searchers with visual arrays that could contain 0–2 targets while inducing anticipatory anxiety via a threat of shock paradigm. In the threat of shock condition, participants occasionally received an unpredictable (aversive, but not painful) electrical shock to the wrist, unrelated to their performance. In the control condition, participants occasionally heard an innocuous tone, also unrelated to performance. Each participant completed 28 10-trial blocks (alternating between conditions), with electrical stimulation occurring pseudo-randomly on four and a tone occurring on four. To focus on anticipation, blocks that contained a shock or tone were not analyzed. Under anticipatory anxiety (confirmed by increased skin conductance levels), participants' dual-target search accuracy was negatively impacted, but single-target accuracy and time-on-task were unaffected; that is, overall performance was relatively stable, except for their ability to detect a second target in an array after having found a first. Further, this effect was modulated by individual differences in state anxiety prior to testing: participants with higher state anxiety scores had higher autonomic arousal overall and thus showed a reduced relative autonomic response to the threat of shock. Likewise, they had a reduced difference in dual-target accuracy between conditions. These findings reveal key impacts on cognitive processes beyond what standard visual search tasks show, and simultaneously inform cognitive theory and real-world searches.
This work was supported by the Army Research Office (#54528LS) and through a subcontract with the Institute for Homeland Security Solutions (IHSS).