“…For instance, phase transitions occur earlier for wrist abduction and adduction movements than for wrist flexion and extension movements (see note 3). At a more cognitive level, movements with compatible spatial codes are easier to perform than those in which such codes are incongruent (Franz, Zelaznik, & McCabe, 1991;Semjen, Summers, & Cattaert, 1995), independent of biomechanics. Such codes may be perceptual in nature (Mechsner, 2004a(Mechsner, , 2004bMechsner et al, 2001; see also Kunde & Weigelt, 2005), and/or they may reflect interactions associated with response selection (Ivry et al, 2004).…”