Sustained visual awareness is associated with a negative event-related potential (ERP) that persists for the entire duration a stimulus is consciously perceived. In a visual task, participants viewed line stimuli presented for 500 or 1000 milliseconds. Some participants were informed that the lines sometimes contained a face, enabling them to see the face through visual one-shot learning, while uninformed participants did not perceive the face. Comparing brain activity between groups showed an enhanced negativity over occipitotemporal electrodes that lasted as long as the stimulus was presented. This sustained visual awareness negativity (SVAN) indicates that awareness-related brain signals correspond to the duration of a conscious percept, not just a transient onset response.
Conscious visual experience ranges from basic features to integrated percepts like faces, but it is unclear whether brain signals linked to consciousness reflect only low-level features or also higher-order content. Using an inattentional blindness design with 85 participants, the study measured brain activity while people perceived either no stimulus, only low-level lines, or a high-level face. Low-level perception produced an early occipital negativity, while face perception additionally recruited a right-lateralized occipitotemporal negativity and later medial posterior positivities. These results suggest that distinct spatiotemporal brain patterns correspond to different representational levels of conscious perception, independent of task-related processes.