Alexis A. Fink and Debra A. Major Old Dominion University
Although definitions vary, the following elements are considered key in defining situation awareness (SA): an awareness of surroundings and objectives, comprehension of their meaning, an ability to observe, process and take action on the basis of relevant information, an awareness of the dynamic nature of the situation and one's current temporal place within the dynamic system, and a planful anticipation of future events ( Endsley, 1995; Sarter & Woods, 1991; Shrestha, Prince, Baker, & Salas, 1995). As this definition suggests, situation awareness is not equally relevant and important across performance contexts. SA is most critical to task performance when operating in a context that is complex, dynamic, risky, cognitively demanding, and time-constrained ( Sarter & Woods, 1991). The environment must be constantly scanned for relevant information, which must be processed, prioritized and incorporated in planning. In this type of context critical cues may be subtle, meaningful only in combination, or fleeting ( Gaba & Howard, 1995). The complexity, criticality, and volume of information presented in the SA context often precludes a single individual working alone from effectively operating in that environment; it is simply too demanding. Therefore, teams are often required to ensure safe, effective decision-making, and appropriate action in this context. In general, teams are defined as "distinguishable sets of individuals who interact interdependently and adaptively to achieve specified, shared and valued objectives" ( Morgan, Glickman, Woodard, Blaiwes, & Salas, 1986, p. 3).
With few exceptions, theoretical and empirical work to date has focused primarily upon SA at the individual level with emphasis on cognitive processes. The shared understanding approach to team SA (e.g., Stout et al., 1996/ 1997) is more complex and comprehensive than others that have been suggested in the literature. According to this perspective, team SA is defined as a function of individual team member SA and the degree of shared understanding among team members. Thus, the same level of team SA may exist either because individual team members are maintaining a high degree of individual level situation awareness, or because there is a great degree of shared understanding among team members. However, Stout et al. contend that the largest incremental increases in team SA will be due to increased understanding among team members. Shared understanding is hypothesized to be the direct result of both shared mental models and team process behavior. Although Stout et al. ( 1996/ 1997) provide a more thorough treatment of the role of mental models in contributing to shared understanding and team situation awareness, the importance of team processes is explicitly acknowledged.
Stout et al. ( 1996/ 1997) argue that one way shared mental models among team members develop is as the result of explicit strategizing and that these mental models then allow for the maintenance of SA under dynamic circumstances in which explicit strategizing is not possible. A key point in this argument is that explicit strategizing among team members must occur in order for an accurate and effective shared mental model to exist. We take the position that while mental models are cognitive constructs, the process by which they become shared among team members is necessarily social. Team members must interact with one another to develop a shared understanding. Thus, the focus of the current effort is to explore the interactive processes by which the shared understanding that is so critical to team SA is developed.