Human brains are basically primate in design, but in addition have representational mechanisms that give human consciousness a special character. The evolution in hominids of new kinds of representational skill--both nonverbal and verbal--produced our capacity for skilled rehearsal and explicit memory retrieval, and allowed the invention of conventional, or public representations, including languages and external symbols. The latter have created demands at the cultural level that greatly influence the deployment of cerebral resources. The spiralling interaction of brain and culture in evolution has resulted in a unique quasi-modular architecture at the highest levels of human cerebral integration.