Tracking the processes behind conscious perception: A review of event-related potential correlates of visual consciousness

• Published in: Consciousness and cognition Vol. 20; no. 3; pp. 972 - 983
• Main Authors: Railo, Henry, Koivisto, Mika, Revonsuo, Antti
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01-09-2011; Elsevier; Elsevier BV
• Subjects: Attention; Awareness; Awareness - physiology; Biological and medical sciences; Cognition & reasoning; Consciousness; Consciousness - physiology; Consciousness and Cognitive Neuroscience; ERP; Evoked Potentials - physiology; Eyes & eyesight; Fundamental and applied biological sciences. Psychology; Humans; Information processing; Kognitiv neurovetenskap och filosofi; Natural sciences; Naturvetenskap; Perception; Perceptions; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Sensory perception; Vision; Visual; Visual Cortex - physiology; Visual Perception - physiology; ERP; Consciousness; Awareness; Visual; Attention; Human; Central nervous system; Electrophysiology; Cognition; Review; Encephalon; Vision; Perception; Event evoked potential
• ISSN: 1053-8100; 1090-2376; 1090-2376
• DOI: 10.1016/j.concog.2011.03.019

► We review the proposed event-related potential correlates of visual consciousness. ► The earliest proposed correlate (P1) reflects preconscious processes. ► Visual consciousness is produced in ventral areas ∼200ms poststimulus (VAN). ► Early contributions from dorsal regions are also essential for visual consciousness. ► Sustained frontoparietal activity is not necessary for visual consciousness.
Event-related potential (ERP) studies have attempted to discover the processes that underlie conscious visual perception by contrasting ERPs produced by stimuli that are consciously perceived with those that are not. Variability of the proposed ERP correlates of consciousness is considerable: the earliest proposed ERP correlate of consciousness (P1) coincides with sensory processes and the last one (P3) marks postperceptual processes. A negative difference wave called visual awareness negativity (VAN), typically observed around 200ms after stimulus onset in occipitotemporal sites, gains strong support for reflecting the processes that correlate with, and possibly enable, aware visual perception. Research suggests that the early parts of conscious processing can proceed independently of top-down attention, although top-down attention may modulate visual processing even before consciousness. Evidence implies that the contents of consciousness are provided by interactions in the ventral stream, but indispensable contributions from dorsal regions influence already low-level visual responses.