One of the final obstacles to understanding consciousness in physical terms concerns the question of whether conscious states can exist in posterior regions of the brain without active connections to the brain's prefrontal lobes. If they can, difficult issues concerning our knowledge of our conscious states can be resolved. This paper contains a list of types of conscious states that may meet this criterion, including states of coma, states in which subjects are absorbed in a perceptual task, states in brains (...) with damaged prefrontal lobes, states of meditation and conscious states of some infants and animals. Recent evidence also suggests that conscious states of some people with autism may meet this criterion. (shrink)