We usually perceive what we are attending to. How goal-directed attention contributes to conscious perception remains yet elusive. Here we combined a novel psychophysical paradigm with intracranial electroencephalography data to investigate this issue in the human brain. Relative to unattended conditions, goal-directed attention modulated early activity and inter-regional connectivity, even though this part of attention failed to predict image detectability. Later, the coupling between the frontal and posterior brain got established and maintained but the signals exchanged did not inform fine-grained image contents but instead reflect success or failure of attentional capture. This part of captured attention proportionally predicted image detectability. These results attribute consciousness to attention-based coupling between the frontal and posterior brain as a whole, rather than activity of either part alone.