Visual awareness of low-contrast stimuli is reflected in event-related brain potentials

Psychophysiology. 2003 Mar;40(2):192-7. doi: 10.1111/1469-8986.00021.

Abstract

Visual awareness was studied in 11 subjects by using coherent and scrambled objects as stimuli. The stimuli were presented near the subjective perceptual threshold. Explicitly recognized stimuli elicited a specific negative ERP deflection peaking at 460 ms. Our reaction time experiment suggests that this visual awareness negativity (VAN) is similar to that found previously at a shorter latency. We propose that VAN might reflect the exact moment of becoming aware of the task-relevant stimulus properties and provide an online marker of the temporal dynamics of visual awareness.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Electroencephalography
  • Evoked Potentials, Visual / physiology*
  • Female
  • Humans
  • Male
  • Reaction Time / physiology
  • Visual Perception / physiology*