Get access

The many faces of preparatory control in task switching: Reviewing a decade of fMRI research

Authors

  • Hannes Ruge,

    Corresponding author
    1. Department of Psychology, Neuroimaging Center, Department of Psychology and Institute of General Psychology, Biopsychology, and Methods of Psychology, Technische Universität Dresden, Germany
    • Technische Universität Dresden, Fakultät Mathematik und Naturwissenschaften, Fachrichtung Psychologie, 01062 Dresden, Germany
    Search for more papers by this author
  • Sharna Jamadar,

    1. Olin Neuropsychiatry Research Center, Institute of Living, Hartford, Connecticut, U.S.A
    2. Functional Neuroimaging Laboratory, School of Psychology and Centre for Brain and Mental Health Research, University of Newcastle, Callaghan, NSW, Australia
    Search for more papers by this author
  • Uta Zimmermann,

    1. Department of Psychology, Neuroimaging Center, Department of Psychology and Institute of General Psychology, Biopsychology, and Methods of Psychology, Technische Universität Dresden, Germany
    Search for more papers by this author
  • Frini Karayanidis

    1. Functional Neuroimaging Laboratory, School of Psychology and Centre for Brain and Mental Health Research, University of Newcastle, Callaghan, NSW, Australia
    Search for more papers by this author

Abstract

A large body of behavioural research has used the cued task-switching paradigm to characterize the nature of trial-by-trial preparatory adjustments that enable fluent task implementation when demands on cognitive flexibility are high. This work reviews the growing number of fMRI studies on the same topic, mostly focusing on the central hypothesis that preparatory adjustments should be indicated by enhanced prefrontal and parietal BOLD activation in task switch when compared with task repeat trials under conditions that enable advance task preparation. The evaluation of this straight-forward hypothesis reveals surprisingly heterogeneous results regarding both the precise localization and the very existence of switch-related preparatory activation. Explanations for these inconsistencies are considered on two levels. First, we discuss methodological issues regarding (i) the possible impact of different fMRI-specific experimental design modifications and (ii) statistical uncertainty in the context of massively multivariate imaging data. Second, we discuss explanations related to the multidimensional nature of task preparation itself. Specifically, the precise localization and the size of switch-related preparatory activation might depend on the differential interplay of hierarchical control via abstract task goals and attentional versus action-directed preparatory processes. We argue that different preparatory modes can be adopted relying either on advance goal activation alone or on the advance resolution of competition within action sets or attentional sets. Importantly, while either mode can result in a reduction of behavioral switch cost, only the latter two are supposed to be associated with enhanced switch versus repeat BOLD activation in prepared trial conditions. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc.

Ancillary