Efficiency of task switching and effects of prediction errors as a function of the number of action alternatives

• Applicant: Professor Dr. Thomas Kleinsorge
• Subject Area: General, Cognitive and Mathematical Psychology
• Term: from 2010 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 173936588

When different tasks are performed in temporal succession, task switches are associated with switch costs, that is, a deceleration of processing speed and an increase in error rates. These switch costs can be reduced by preparation, but at present, it is unclear inasmuch efficient preparation depends on the availability of external stimuli (exogenous preparation) or can proceed solely on the basis of internal representations like plans (endogenous preparation).We could show that the extent of endogenous preparation is smaller when people switch among only two tasks (as in most studies of task switching), whereas switches among four tasks are more susceptible to effects of endogenous preparation. Furthermore, we obtained evidence for a mechanism of establishing antagonistic constraints when switching among two tasks which is thought to facilitate task switching based on external stimuli. In addition, we provided evidence that explicit expectations of a certain task result in a boost of cognitive control when the relevant task differs from the expected one. We plan to follow up on these studies by contrasting processes of expecting a task with processes of choosing among tasks. Task expectation and task choice differ with respect to the degree that people experience control over an upcoming task. We propose a paradigm in which the degree of objective control is the same for task predictions and task choices. Our goal is to investigate whether both situations result in the establishment of antagonistic constraints when the number of tasks is reduced from four to two. Furthermore, we plan to compare the recruitment of cognitive control processes induced by a task that differs from the expected or chosen one, and to examine the modulating effects of different numbers of tasks and, in comparison to that, different numbers of motor actions on these processes. In addition, we plan to investigate whether differences in the degree of experienced control for task predictions and task choices go along with variations in the sense of agency, and whether such variations in turn modulate the recruitment of cognitive control processes.

• DFG Programme: Research Grants