Effects of response selection on the task repetition benefit in task switching.
A task switch typically leads to worse performance than a repetition does. This shift cost can be reduced with sufficient task preparation time, but a residual cost usually remains. We propose that a large part of this residual cost is caused by an activation bias produced by response selection processes in the preceding trial. In our experiments, we manipulated response selection requirements using a go/no-go methodology. The residual shift cost disappeared after no-go trials, suggesting that response selection is crucial to establish an activation bias for the current category-response rules and that this bias persists into the next trial. A comparison with a go-only group confirmed this analysis by revealing no differences in preparatory strategy due to the inclusion of no-go trials. In addition, no-go trials had no significant effects on subsequent trials in a single-task experiment, suggesting that no-go trials are not coded as a task different from go trials and that there is no inhibition of the prepared task in a no-go trial. We thus conclude that a persisting activation bias of response rules plays a major role in task switching.
Koch
Iring
I
Department of Psychology, Max Planck Institute for Human Cognitive and Brain Sciences, Munich, Germany. iring.koch@cbs.mpg.de
Philipp
Andrea M
AM
D000328:Adult; D002755:Choice Behavior; D005260:Female; D006801:Humans; D008297:Male; D011930:Reaction Time