The frame/content theory of speech production is restricted to output mechanisms in the target article; we suggest that these ideas might best be viewed in the context of language production proceeding as a coordinated dynamical whole. The role of the medial premotor system in generating frames matches the important role it may play in the internally dependent timing of motor acts. The proposed coevolution of cortical architectonics and language production mechanisms suggests a significant divergence between primate and cetacean species corresponding (...) to major differences in areal differentiation trends in cerebral cortex. (shrink)

Research reported by Posner & Raichle may be usefully applied to the rehabilitation of persons with brain damage. Their findings are related to the “dual premotorsystems hypothesis” that reciprocally interactive medial and lateral brain systems are involved in attention and learning. Recent studies show that “brain healing” occurs through dynamic reorganization involving attentional networks postulated by Posner & Raichle.