Imaging the Networks of Voluntary Actions

The concept of voluntary actions is inextricably related to the concept of the will. Accordingly, in the first section of this chapter, the authors examine briefly the neuroimaging evidence for a neuronal mechanism of human will and decision-making and conclude that what evidence is brought to bear on the issue may not be relevant to it after all. In the second section, a review of the known mechanism for self-initiated as well as externally mediated voluntary actions is presented against which the contributions of functional neuroimaging to improving our knowledge for simple and complex actions can be judged. In the final section differences in the neuronal networks mediating decisions as to when to act and what action to select are explored.