Transactive Memory and Team Mental Models

One construct especially relevant for understanding team knowledge processes is a transactive memory system. Mohammed and Dumville (2001) developed an integrative framework which describes team mental models as the broader concept, and transactive memory systems as addressing a specific dimension of team mental models.

Transactive memory systems were conceived by Wegner (1987), who observed that members of long-tenured groups tend to rely on one another to obtain, process, and communicate information from distinct knowledge domains. Wegner termed this system of cognitive interdependence, a Transactive Memory System (TMS). Wegner (1987) posited that knowledge specialisation is greater in groups with well-developed TMSs. Specialisation enables individuals to define their expertise more deeply. A TMS is the cooperative division of labour for learning, remembering, and communicating relevant team knowledge, where one uses others as memory aids to supplement limited memory (Hollingshead, 2001; Wegner, 1987). By specialising knowledge in a group and having a shared awareness of who knows what information, cognitive load is reduced, greater access to expertise can be achieved, and there is less redundancy of effort. Retrieving the information stored in another person’s memory, however, depends on transactions (communication, interpersonal interactions) between individuals (Lewis, 2003). This specialisation needs to be coordinated, which resolves task dependencies that result from work differentiation (Crowston, 1997).

Transactive memory is concerned with heedful interactions and awareness of the location of expertise and implies the development o f a collective mind (Weick & Roberts, 1993; Berman et al. 2002). Weick and Roberts (1993) introduced the concept of ‘heedful interrelating’ where each action is modified by its predecessor. This is an important concept for understanding how teams coordinate their actions. When people engage in tasks with similar people for a period of time, then collaborative patterns emerge.

It can be concluded from the preceding discussion, that transactive memory involves the awareness of specialisations (or expert knowledge) and coordination of this differentiated knowledge. Specialised knowledge and its coordination may be acquired through experience of working in a domain. Transactive memory associated with expertise and experience, leading to the following predictions:

H ypothesis 2

Hypothesis 3

Transactive memory will be positively related to experience.

2.7.1 T ransactive M em ory and Team Perform ance: E m pirical Studies

Most research in transactive memory and its relationship to team performance, has been conducted in groups which are brought together for the express purpose of studying transactive memory. The teams are generally asked to complete a task and disbanded after the task is complete (Austin, 2003). Team performance in these studies is measured by both the efficient and effective completion of the task, where efficiency refers to budget and schedule and effectiveness is the achievement of project goals (Daft, 2004). The findings of the mostly laboratory based studies are now outlined.

Moreland and colleagues (Liang et al. 1995; Moreland et al. 1996) in a series of laboratory experiments investigated the development of transactive memory through training. Transactive memory was measured by observing student groups as they assembled AM radios. These authors uncovered group dynamics that contributed to the existence of a transactive memory system. These dynamics included specialisation of task, task coordination activities and task credibility and concluded that a ‘transactive memory system can substantially improve a work group’s performance, and that training the group members together is a reliable way to produce such a system’ (p. 18). Studies by Wegner and colleagues (Wegner et al. 1991) and Hollingshead (1998a; 1998b) provide evidence that these cooperative cognitive systems do develop in dyads. Wegner argued that similar systems exist in groups. Like the TMSs of dyads, a group TMS exists when members actively use their transactive memories to draw upon and combine others’ knowledge to perform a joint task.

Lewis (2003) developed a field measure o f TMSs, holding that TMSs could be discerned from the differentiated structure of members’ knowledge (specialisation), members’ beliefs about the reliability of other members’ knowledge (credibility), and effective, orchestrated knowledge processing (coordination). In one study of 64 MBA student teams, Lewis found that total scores on the TMS measure and scores on all three factors were associated with successful performance. However, another study of 27 teams from high technology industries, revealed that total scores on the TMS and the factors of coordination and credibility were associated with successful team

performance, but specialisation was not. Lewis (2003) argued that there were three team types, project, cross-functional and functional and that team type may be a boundary. Functional teams work in parallel where specialisation may be important but its integration is not, the relationship between specialisation and team performance was weak (only r = 0.04). However, Lewis (2003) cautions that the small sample size limits generalisation.

Finally, Austin (2003) examined the relationship between transactive memory and performance in 27 mature, continuing groups and found that transactive memory was related to group performance.

These studies form the basis for the following prediction:

H ypothesis 4

Transactive memory will be positively related to team performance as measured by effectiveness and efficiency.

2.7.2 E valuation o f the T ransactive M em ory C onstruct

According to Moreland (1999) expertise recognition is an important part of transactive memory, as it guides group members to those members with relevant information and to evaluate the information based on the source. There may also be a downside to the benefits of differentiated knowledge and transactive memory systems (Lewis, 2003). Teams do not need to share some overlapping knowledge to perform well, what is not known is how much knowledge must be overlapping, and how much specialisation is too much. Too much specialisation will only create ‘islands of expertise’, without mutual dependence. Members may also possess complementary specialisations that are not efficient but persist anyway. If members have developed tacit coordination patterns they may be less likely to question the credibility o f members’ expertise.

Mohammed and Dumville (2001) point out that developing a transactive memory system reduces the rehashing of shared information and allows for the pooling of unshared information. The development of a transactive memory system is probably slow and gradual (Moreland, 1999). As workers spend time together they become more familiar with one another.

2.7.3 T he R ole o f Social Interaction for the D evelop m en t o f a TM S

Transactive Memory is a form of TMM. As such, it is developed through social interaction within the team, where informal interaction is considered the most successful type o f communication in groups. TMSs develop as team members learn about one another’s expertise (Wegner, 1987), accomplished predominantly through interpersonal communication (Hollingshead, 1998a). Evidence for the relationship between transactive memory and social interaction is found in the field study by Lewis (2003) who measured functional or ‘task-relevant’ communication and found that it was related to transactive memory. Laboratory studies have also consistently shown TMSs to predict higher performance in couples’ recall (Hollingshead, 1998a; Hollingshead, 1998b), and work team performance (Liang et al. 1995; Moreland & Myaskovsky, 2000), than non-interacting dyads. However, it must be noted that these studies do not differentiate between quality and quantity of interaction. On the basis of this discussion the following hypothesis is forwarded:

Hypothesis 5

Social interaction (quality and quantity) will vary according to transactive memory