The influence of cue-task association and location on switch cost and alternating-switch cost.

Abstract

Task-switching performance is strongly influenced by whether the imperative stimulus uniquely specifies which task to perform: Switch cost is substantial with bivalent stimuli but is greatly reduced with univalent stimuli, suggesting that available contextual information influences processing in task-switching situations. The present study examined whether task-relevant information provided by task cues influences the magnitude of switch cost in a parallel manner. Cues presented 500 ms prior to a trivalent stimulus indicated which of three tasks to perform. These cues either had a preexisting association with the to-be-performed task (verbal cues), or a recently learned association with the task (spatial and shape cues). The results paralleled the effects of stimulus bivalence: substantial switch cost with recently learned cue-task associations and greatly reduced switch cost with preexisting cue-task associations. This suggests that both stimulus-based and cuebased information can activate the relevant task set, possibly providing external support to endogenous control processes. Alternating-switch cost, a greater cost for switching back to a recently abandoned task, was also observed with both preexisting and recently learned cue-task associations, but only when all tasks were presented in a consistent spatial location. When spatial location was used to cue the to-be-performed tasks, no alternating-switch cost was observed, suggesting that different processes may be involved when tasks are uniquely located in space.

Task inhibition and task repetition in task switching

“…In the experiment conducted by Dreher and Berman (2002), the N Á2 repetition cost was found, but a possible N Á1 shift cost was not reported. Finally, the study of Arbuthnott and Woodward (2002) demonstrated robust N Á1 shift cost under all conditions, whereas the N Á2 repetition cost occurred only under some conditions. Taken together, it seems that there is no consistent data pattern with respect to the occurrence of N Á1 shift cost and NÁ2 repetition cost.…”

“…We are aware of six other studies in which task repetitions occurred in experiments with three tasks, and which thus are relevant to explore the influence of task repetitions on N Á2 repetition cost (Arbuthnott & Frank, 2000;Arbuthnott & Woodward, 2002;Dreher & Berman, 2002;Mayr, 2001Mayr, , 2002Mayr & Keele, 2000). Three of these studies (Mayr, 2001(Mayr, , 2002Mayr & Keele, 2000) report finding N Á1 shift cost and NÁ2 repetition cost.…”

“…In recent years, several studies have been published in which taskswitching experiments with three different tasks included the occurrence of task repetitions (Arbuthnott & Frank, 2000;Arbuthnott & Woodward, 2002;Dreher & Berman, 2002;Mayr, 2001Mayr, , 2002Mayr & Keele, 2000). To our knowledge, only the study by Mayr and Keele (2000) included experiments with and without task repetitions.…”

“…But although these authors argued that there is no change in the size of the N Á2 repetition cost in an experiment with task repetitions (Experiment 4) as compared to an experiment without task repetitions (Experiment 1), no direct betweenexperiment analysis was reported. However, such a direct comparison would be important because the N Á2 repetition cost was not found consistently in all experiments including task repetitions (see, e.g., Arbuthnott & Woodward, 2002). We intend to focus on this question more systematically by manipulating the occurrence of task repetitions between as well as within subjects.…”

Interpreting instructional cues in task switching procedures: The role of mediator retrieval.

“…Several studies have shown that transparent cues produce smaller switch costs than nontransparent cues (Arbuthnott & Woodward, 2002;Logan & Bundesen, 2004;Mayr & Kliegl, 2000;Miyake, Emerson, Padilla, & Ahn, 2004). The present investigation attempted to distinguish between two explanations of the difference in switch costs between transparent and nontransparent cues: association strength and mediated retrieval.…”