Consciousness is discontinuous. The transition from the raw output of parallel, distributed processors into the unified, serial content of consciousness is not instantaneous. Consciousness is divided into discrete cycles, yet appears to be continuous. The continuity requires temporal integration. The simplest mechanism is the calculation of the direction and magnitude of change from one conscious cycle to the next and then the fusion of these conscious vectors with the content of subsequent cycles. This mechanism, while putative, has supporting evidence. It is based on the same mechanism as motion vision, in which motion vectors are calculated in MT/V5 and then fused with discrete images. Moreover, it is based on the known separation of cognitive timing in the brain, in which temporal integrity is maintained in the prefrontal cortex (PFC) and the rest of the content of consciousness is maintained in the rest of the cortex. In fact, limited activity of the PFC matches the predicted effects of the absence of conscious vectors: thoughts strobe and consciousness disintegrates into a series of discrete cycles. The PFC, for example, is one of the primary brain regions deactivated during dreaming, when thoughts shift without any awareness of the transitions. In addition, the PFC is immature in infants, when there is no memory of the experience of consciousness because there is no temporal integrity to assemble the discrete cycles into a coherent experience. Without temporal integration, the human brain is an advanced biological computer, but is not sentient.