Understanding consciousness is one of the most important and challenging questions in modern science. Existing theories have pursued single unifying mechanisms but do not succeed in explaining consciousness. Importantly, the neural circuits that distinguish messages that arrive from the outside world and attain consciousness have remained unknown. Here we identify signals throughout the entire brain at high spatiotemporal resolution specifically related to consciousness. To accomplish this, we combined a large sample size of electrical and neuroimaging data with a novel experimental approach to remove confounding signal unrelated to consciousness1-3. We discovered three major brain networks driving conscious visual perception. First, we found increases in signal detection regions in visual, fusiform cortex, and frontal eye fields; and in arousal/salience networks involving midbrain, thalamus, nucleus accumbens, anterior cingulate, and anterior insula. Second, we found increases in frontoparietal attention and executive control networks and in the cerebellum. Finally, we found decreases in the default mode network. Our results identify subcortical and cortical networks designed for signal detection, attentional amplification, and perceptual processing that together can explain visual consciousness. These findings provide evidence that understanding consciousness can be reframed as requiring multiple overlapping brain networks to produce consciousness of visual events4.