Corey K. Fallon

Enhancing Perceived Situation Awareness and Reducing Perceived Workload with a Likelihood Alarm Display

The researchers investigated the effects of a likelihood alarm display (LAD) on perceptions of workload and situation awareness (SA) during varying degrees of taskload. Twenty-four psychology students reacted to alarms while performing a complex primary task. The researchers examined participants performances during four experimental sessions. Two conditions of alarm display (binary and likelihood) and task load (low and high) were manipulated within groups. In addition, alarm display order (binary first or likelihood first) and task load order (low first or high first) were examined between groups. Results showed greater SA and reduced workload when participants used a likelihood alarm display and when they experienced low task load. Significant order effects also occurred. This study demonstrated the positive effects of a likelihood alarm display on perceptions of workload and SA, and suggests that LAD use may reduce workload and enhance SA.

Crowd Reactions to Sublethal Weapons: Universal Triggers for Crowd Violence:

Since the end of the cold war, military forces have increasingly been required to manage crowds of people, some of which may quickly turn violent. Frequently, crowd researchers identify “flashpoint” variables: environmental or social triggers that cause a crowd to become hostile. The goal of this research was to identify potential flashpoints, to assist the simulation and training communities in crowd representation. Researchers exhaustively reviewed crowd literature, surveyed subject matter experts in crowd control, and analyzed anecdotal crowd events. Survey results indicated that crowd weapons, alcohol and drugs, crowd commitment, and crowd desperation may be flashpoints for violence. However, none of these variables strongly varied with culture. Anecdotal results revealed additional flashpoint variables, such as aggression and the use of auditory stimuli by control force members, instigators within the crowd, and general masculine culture. These findings agree in part with results from existing literature, and have implications for peacekeeper training.

The Effects of Alarm Mistrust and Signal Duration on Alarm Reactions and Perception of Alarm Validity

Researchers have begun examining variables that may moderate the degrading effects of alarm mistrust on alarm reaction performance. We examined alarm systems of varying reliability levels (60 or 80 percent true alarms) that generated either short or long duration alarms. We studied the impact of these variables on participant response frequency and perception of signal validity. The researchers sampled 40 Old Dominion University psychology students. We predicted that participants would rate long duration alarm signals as more representative of a valid signal. We also believed that participants would use the representativeness heuristic as a response strategy. The results partially supported our hypotheses. Participants rated the long duration signals as significantly more representative of a valid signal (p<.001). However, although participants responded significantly more often to long duration alarms (p<.01), participants in the 80% reliability group responded to significantly more alarms than those in the 60% reliability group (p=.02). The performance results are inconsistent with our hypothesis. Although participants perceived the long duration alarms to be more representative than the short, they did not base their response strategy entirely on alarm representativness. Despite these unexpected findings, the results suggest that alarm signal duration has a significant impact on alarm response frequency. Therefore, designers of complex systems may be able to moderate response degradation due to unreliability by designing systems that generate long duration alarm stimuli.

The Effects of Relative System Reliability and Prioritization on Alarm Reaction Patterns

Alarm system operators often manage multiple alarm systems concurrently. Because such situations often accompany cascading events, it is important to know how operators sequence responses. We examined how the relative reliability and priority of two concurrent alarms affected alarm gauge reset patterns. We hypothesized that operators would respond first to an alarm with higher reliability or higher priority when the other variable was held constant. We also expected participants to respond to alarms with higher priority first when they occurred at the same time as a high-reliability alarm. Sixty-one Old Dominion University undergraduates performed a tracking task and responded to gauge fluctuations (alarms). A between subjects ANOVA revealed that participants responded to alarms with higher priority first when reliability was constant, and to higher reliability alarms first when priority was constant. Our results suggest that relative priority and reliability may be useful parameters to control in complex task situations.

Weather Deviation Decisions by Air Transport Crews during Simulated Flight

As the variety and capabilities of cockpit weather displays have increased, weather deviation decisions have become more complex. Important issues include conflicting or outdated weather information, and teamed reactivity of crews to weather displays. We investigated the influence of onboard and NEXRAD agreement, range to the simulated potential weather event, and the pilot flying on collective weather deviation decisions. Twelve pilot-copilot teams flew a simulated route while reacting to weather events presented in two graphical formats on a separate visual display. Results showed that pilots often chose to deviate from weather rather than confront it. When onboard and NEXRAD displays did not agree, flight crews reacted by trusting the onboard system more but using the NEXRAD system as a backup. These results suggest that future weather displays should exploit existing benefits of NEXRAD presentation for situation awareness while retaining the display structure and logic inherent in the onboard system.

Combating Cry Wolf: The Effects of Synthetic Verbal Alarm Urgency on Choice Reaction Performance:

Researchers have shown that increasing the perceived urgency of nonverbal auditory alarms can meliorate alarm response performance degradation due to the cry wolf effect. We conducted two experiments to examine the effects of verbal alarm urgency on the cry wolf effect. Experiment 1 revealed that participants responded significantly less often and correctly rejected more urgent alarms. Experiment 2 revealed that the results in Experiment 1 were contingent on the presence of additional task critical information. Response degradation due to the cry wolf effect was not moderated by alarm urgency in either study. However, the results suggest that performance may still benefit from increased alarm urgency provided additional task critical information is available. These results can be utilized to design verbal alarm systems that evoke more appropriate reactions to false alarms.

The Effects of Leadership Style and Workload on Team Alarm Reaction Performance and Team Satisfaction

Previous research has indicated that flight crew communication problems cause the majority of human errors in aircraft cockpits. Such problems may further degrade reaction decisions to unreliable alarm signals. In this research we examine how leadership style and workload affect collective reactions to unreliable alarms. Seventeen psychology student dyads from Old Dominion University were randomly assigned to act as pilots or copilots while performing complex psychomotor and alarm response tasks. Dyad leaders (pilots) were assigned to exhibit autocratic or participative leadership behaviors. Dyads reacted to ten alarms in each condition and were randomly assigned to a low or high psychomotor task workload group. Results indicated that dyads in the low workload group reacted to alarms significantly faster than dyads in the high workload group. Also, copilots indicated higher leadership satisfaction in the participative style. These findings suggest that alarm designers consider workload when implementing alarm systems, and that pilots should be trained to exhibit participative leadership qualities.