EVOLUTIONS MISSING LINK - A HYPOTHESIS UPON NEURAL PLASTICITY, PREFRONTAL WORKING-MEMORY AND THE ORIGINS OF MODERN COGNITION

Many activities such as reading, mathematics and chess depend upon cog nitive processes which arose after our evolution. Why could they arise if not evolved? I argue four things fortuitously came together to mak e our nonevolved cognitive skills possible: (i) neural plasticity; (ii ) large functionally uncommitted prefrontal, temporal and parietal cer ebral cortices; (iii) the ability of their neural circuits (due to neu ral plasticity), if trained, to take on novel symbolic and nonsymbolic skills; and (iv) a large prefrontal cortex which could use its workin g memory as a tuition management sketch pad in which to train them. Pr e-evolved for other reasons, these four (together with invented symbol ic systems and technology) together enable modern humans to 'upgrade' our already evolved cognitive skills to do new and nonevolved things.