“…Although handedness has been attributed to genetic factors (Sun and Walsh, 2006), the exact basis and neuronal correlates remain to be determined. Several postmortem (Witelson and Kigar, 1992;White et al, 1994;Amunts et al, 1996), structural (Amunts et al, 2000;Good et al, 2001;Büchel et al, 2004;Herve et al, 2005Herve et al, , 2006, and functional magnetic resonance imaging (fMRI) studies (Kim et al, 1993;Dassonville et al, 1997;Singh et al, 1998;Solodkin et al, 2001;Klöppel et al, 2007) have shown structural and functional hemispheric asymmetries between adult rightand left-handers (for review, see Serrien et al, 2006;Sun and Walsh, 2006). However, on the basis of these studies, it is impossible to infer whether handedness-related differences are determinant or reflect a long-term consequence of actual hand use.…”