Dissociating neural indices of dynamic cognitive control in advance task-set preparation: an ERP study of task switching.

Switching between different tasks is associated with performance deficits, or 'switch costs', relative to repeating the same task. Recent evidence suggests that response rather than task selection processes may be a major cause of switch costs [Schuch, S., Koch, I., 2003. The role of response selection for inhibition of task sets in task shifting. J Exp Psychol Hum Percept Perform, 29 (1) 92-105]. Thus, switch costs are not incurred if on the preceding trial a task has been prepared for but no response required (a 'no-go' trial). We investigated the relationship between response selection and the subsequent preparation of an alternative task set. While switch costs were absent following 'no-go' trials, ERP differences during the precueing interval showed that response selection has implications for subsequent task preparation as well as for task performance per se. The results are discussed in relation to the dissociation of intention versus action in behavioural control and the role of inhibition in switching between task sets.