Now, where was I? Examining the Perceptual Processes while Resuming an Interrupted Task

Now, where was I? Examining the Perceptual Processes while Resuming an Interrupted Task Raj M. Ratwani (rratwani@gmu.edu) George Mason University, Department of Psychology Fairfax, VA J. Gregory Trafton (trafton@itd.nrl.navy.mil) Naval Research Laboratory Washington, D.C applied to interruptions (e.g., Long Term Working Memory, (Ericsson & Kintsch, 1995; Oulasvirta & Sarrlilouma, 2004)), however, these theories do not make clear predictions about the specific processes used to resume an interrupted task. Altmann and Trafton (2002) have put forward an activation based memory model specific to the resumption of an interrupted task. This theory, called Memory for Goals, suggests that an interrupting secondary task results in a suspension of the current subgoal of the primary task. The resumption lag is a consequence of the time it takes to retrieve the suspended subgoal after completing the interrupting task. The most active goal is the goal that will be retrieved and the goal that will be selected to drive behavior. The theory suggests there are two determinants of goal activation, and consequently, two determinants of what goal will be retrieved when resuming the primary task. First, the activation of a goal is based on its history; for example how frequently the goal has been retrieved and how recently the goal was retrieved will impact goal activation. In addition, the activation is based on context and the environment. The context provides priming of the suspended goal resulting in a boost in its activation. Several things should be noted about this description. First, the theory does not make any specific predictions about the perceptual processes used or needed to resume the primary task. Different environmental cues have been shown to facilitate resumption lag (Trafton, Altmann, & Brock, 2005), but the interaction between perceptual processes and environmental cues is currently unspecified. Second, the memory for goals theory (and others) make the assumption that resuming a task is, in large part, a matter of determining what had been done previously. For many tasks (e.g., computer based interactions), however, determining where in the task or interface pre-interruption work had occurred is just as important as determining what had been done previously. The purpose of this paper is to examine the specific perceptual processes involved in resuming the primary task during the resumption lag. In order to examine the perceptual processes during the resumption lag a spreadsheet task was selected that had a flat goal structure. This flat goal structure allowed us to focus on where the resumption point should be rather than on what had been Abstract Several empirical papers have demonstrated that interruptions are disruptive and that after being interrupted it takes some time to resume the primary task. This study examined the cognitive processes, specifically at the perceptual level, that were used to resume a task after being interrupted. Eye movement data showed that participants were able to use spatial memory to return to the general area where they were interrupted. This spatial heuristic was used for interruptions that occurred both early and late in the primary task, however, participants were more imprecise when returning to the task after a late interruption. Introduction There is a great deal of evidence suggesting that in most instances interruptions are disruptive. Several empirical studies have demonstrated how detrimental an interruption can be to primary task performance (Altmann & Trafton, 2004; Monk, Boehm-Davis, & Trafton, 2004; Trafton, Altmann, Brock, & Mintz, 2003). Being interrupted can result in more errors on the primary task, a longer time to complete the primary task and greater feelings of stress and anxiety when performing the task (Adamcyzk & Bailey, 2004; Speier, Vessey, & Valacich, 2003). One dependent measure that has been used to examine how disruptive an interruption can be is the resumption lag (Altmann & Trafton, 2004; Trafton et al., 2003). The resumption lag has been operationally defined as the time interval between the completion of the secondary (interrupting) task and the first action back on the primary task. The resumption lag is essentially the time it takes to resume the primary task after completing the interrupting task. For example, while working on a paper (the primary task) a student may stop by (interrupting task) to talk about research ideas. Once the student leaves, the time it takes to focus one’s thoughts back on the paper and actually resume writing the paper is the resumption lag. How does one go about resuming the primary task after being interrupted? Several studies have illustrated a significantly longer resumption lag after being interrupted as compared to a control condition (Altmann & Trafton, 2004; Monk et al., 2004; Trafton et al., 2003). However, most of the research on interruptions has dealt with reducing or changing the resumption lag, not on the processes used to resume the primary task. Several general memory theories have been