On the zombie within

Abstract

To what extent are we conscious of everything going on in our brains? Nietzsche and Freud popularized the notion of the unconscious as a realm of the mind that controls human behaviour but is not itself accessible to conscious introspection or knowledge. By 'unconscious' we mean any neuronal activity that does not give rise to conscious sensation, thought or memory. Although many of Freud's ideas, involving penis envy, the Oedipus complex, the Id and other fanciful creations, are mere myths that lack objective standing, science has provided credible evidence for the existence of sensorimotor systems in the primate brain that function in the absence of consciousness.