Neural bases of praxis and target-dyrected actions
Neuroimaging evidence (Kroliczak and Frey 2009) indicates that, in right-handers, the left-hemispheric praxis representation network (PRN) constitutes a general domain neural substrate for the planning of meaningful actions, whether or not they involve objects. Less is known about the relationship between PRN and motor dominance in consistent left-handers. Nevertheless, more recent neuroimaging in healthy left-handed adults also shows that planning either transitive/tool use pantomimes or intransitive gestures is associated with increases of activation in the same cortical regions. In addition to the left parietal cortex, however, these increases tend to be more bilateral and involve the dorsal premotor and pre-supplementary motor cortices, as well as the rostral middle frontal gyri. These data suggest that despite reversed motor dominance and more bilateral PRN, planning any meaningful actions might be represented in a common network. The results will be discussed in the context of cortical areas mediating real, target-directed actions.