MATURATION OF THE HUMAN FRONTAL LOBES - PHYSIOLOGICAL EVIDENCE FOR STAGING

The issue of continuous versus discontinuous cognitive development was evaluated in terms of the nonlinear dynamics of human cerebral maturation. Convergent evidence from studies of the development of cerebral architecture, the development of EEG relative power, and the development of EEG coherence demonstrate oscillations and equilibrium processes that underlay cerebral maturation. Life-span development was shown to be a "wave" process with spectral characteristics determined by anatomy. The frontal regions exhibited different wave characteristics than posterior regions, similarly, the left and right hemispheres exhibited differential developmental features. The establishment of corticocortical connections with different regions of the frontal lobes were shown to sequentially occur and to dominate postnatal cerebral development from birth to age 16.