“…1 The principles underlying parameter specification have been extensively investigated in human behavioral studies (for a review, see Rosenbaum, 1983), functional neuroimaging studies (e.g., Deiber, Iban˜ez, Sadato, & Hallett, 1996;Lee, Chang, & Roh, 1999), event-related brain potential (ERP) studies (for a review, see Leuthold, Sommer, & Ulrich, 2004), as well as in monkey neurophysiological studies (e.g., Kurata, 1994;Requin, Riehle, & Seal, 1993). However, at least to our knowledge, the issue of parameter specification in relation to action selection has only been addressed by a very few behavioral studies producing mixed results (Lee et al, 1987;Roth, 1988;Wright et al, 2001). In the present article, we therefore propose to use event-related potentials (ERPs) in addition to behavioral measures in an attempt to test whether motor preparation follows a fixed order of motor program selection followed by parameter specification.…”