Methodological and empirical issues when dissociating cue-related from task-related processes in the explicit task-cuing procedure.
In the explicit cuing version of the task-switching paradigm, each individual task is indicated by a unique task cue. Consequently, a task switch is accompanied by a cue switch. Recently, it has been proposed that priming of cue encoding contributes to the empirically observed switch costs. This proposal was experimentally supported by using a 2:1 mapping of cues to tasks, so that a cue switch does not necessarily imply a task switch. The results indeed suggested a substantial contribution of "cue-switch costs" to task-switch costs. Here we argue that the 2:1 mapping potentially leads to an underestimation of "pure" task-switch costs. To support this argument, we report the results of a new study in which we used "transition cues" that indicate the identity of the current task based on the identity of the preceding task. This new type of cue allows a full factorial manipulation of cue switches and task switches because it includes the condition in which a cue repetition can also indicate a task switch (i.e., when the "switch" cue is repeated). We discuss the methodological implications and argue that the present approach has merits relative to the previously used 2:1 mapping of cues to tasks.
Forstmann
Birte U
BU
Department of Cognitive Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstrasse 1a, 04103 Leipzig, Germany. forstman@cbs.mpg.de
Brass
Marcel
M
Koch
Iring
I
D000328:Adult; D003463:Cues; D036262:Empirical Research; D005260:Female; D006801:Humans; D033182:Intention; D008297:Male; D011584:Psychology / Q000379:methods* / Q000706:statistics & numerical data; D011930:Reaction Time