Different Electrophysiological Correlates of Visual Awareness for Detection and Identification.
Journal of cognitive neuroscience September 1, 2017 Mika Koivisto, Simone Grassini, Niina Salminen-Vaparanta et al.
Conscious detection of an object and conscious identification of that object rely on different neural processes. In an experiment measuring event-related potentials (ERPs), participants performed tasks requiring either detection or identification of a visual stimulus. Behaviorally, a stimulus could be consciously detected without being identified. A posterior electrophysiological signature occurring 200-300 milliseconds after stimulus onset was sensitive to conscious detection but not to identification, which correlated with later widespread brain activity. These findings provide behavioral and neural evidence for elementary visual experiences that are not yet enriched with higher-level knowledge, suggesting that research on consciousness should focus on early phenomenal experiences to avoid confounding effects of higher-level processes.