Self-Generated Expectations of Hazard Prevalence Affect Virtual Search and Rescue.

Area of Science:

• Human-Computer Interaction
• Cognitive Psychology
• Emergency Response Simulation

Background:

• Prior expectations influence visual search in controlled settings.
• Limited understanding of expectation-instruction interaction in simulated emergencies.

Purpose of the Study:

• Investigate how prior expectations and hazard prevalence instructions affect high-stakes visual search.
• Examine search performance in a simulated firefighter search and rescue mission.

Main Methods:

• 48 participants trained with varied hazard prevalence (2 or 6 explosive cylinders).
• Test blocks involved explicit instructions on prevalence changes (increase, decrease, similar).
• Stress manipulated via alarm, explosion threat, and reduced speed; performance measured by stimuli removed; stress assessed via self-report and physiology.

Main Results:

• Lower test prevalence than training increased hazard removal and false positives (distractors removed).
• Prevalence changes led to more errors compared to similar prevalence conditions.
• False negative errors remained low across all conditions.

Conclusions:

• Acquired hazard expectations can override explicit instructions, causing persistent search errors.
• Difficulties in adjusting decision criteria likely contribute to these errors.
• Training for high-stakes hazard search needs methods to mitigate outdated expectations.