Learning Virtual Space
The ability to ‘learn’ the environment before engaging in navigation is an area of interest for a variety of application domains (Egsegian et al., 1993, Foreman et al, 2003). Traditionally spatial training is accomplished by providing users with maps and briefings of an environment. These methods, however, only provide topological knowledge of the environment, which whilst being more flexible, pays little attention to the details of routes and landmarks (Thorndyke, 1980; Golledge, 1991). Procedural learning has a distinct advantage as can be seen in the experiments of Thorndyke and Hayes-Roth (1982); where participants with procedural knowledge of an environment estimated route distances significantly better than participants who had acquired just topological knowledge. Navigation therefore appears to rely heavily on previously acquired visual information, e.g. the process of re-orientation during navigation in a previously visited environments (Montello, 2005), which relies on previously seen “visual references” in order to adjust bearings during navigation. Maps and other traditional navigational equipment cannot provide this level of supporting information. VE training promises to provide procedural knowledge through exploration, and has caught the attention of a variety of researchers all attempting to determine whether virtual training is more efficient than training through more traditional methods (Witmer et al., 1995; Goerger et al., 1998; Waller et al., 1998; Foreman et al., 2003).
Learning in virtual environments relies on the ability of users to develop an understanding of space by creating a cognitive map of the environment (Asthmeir et al., 1993; Cobb and d’Cruz, 1994; Silverman and Spiker, 1997; Clark and Wong, 2000; Riva and Gamberini, 2000). Cognitive maps are mental representations of space that people develop in order to acquire an understanding of space, both virtual and real, through either procedural knowledge or survey knowledge (Thorndyke, 1980; Golledge, 1991; Witmer et al., 1995; Goerger et al., 1998). When learning in a procedural manner, cognitive maps are created through the act of navigation (Montello, 2005). Navigation itself is made up of two separate and very distinct processes. The first of these processes is locomotion, which is the movement of a person within an environment. The second process is way-finding, which is the planning of routes that a person undergoes when trying to get to a specific destination (Montello, 2005). It is understood that during self-directed locomotion (where the person is actively moving about in the environment solving problems - such as avoiding obstacles), there is a tendency to acquire more spatial knowledge (Feldman and Acredolo, 1979). Virtual environment training provides self-directed locomotion without the possibility of a dangerous life-threatening situation, making it very suitable for emergency and military training.
Interestingly, research concerning spatial knowledge acquisition through VEs, provides a variety of contradicting results. The findings, although conflicting, appear to be subject to a key influencing factor, ‘required exposure time’ (Witmer et al., 1996; Darken and Banker, 1998; Waller et al., 1998; Goerger et al., 1998; and Darken and Peterson, 2001). This factor is the exposure time that a user will spend learning the environment in order to achieve spatial knowledge acquisition.