Robust single trial identification of conscious percepts triggered by sensory events of variable saliency

PLoS One. 2014 Jan 23;9(1):e86201. doi: 10.1371/journal.pone.0086201. eCollection 2014.

Abstract

The neural correlates of visual awareness are elusive because of its fleeting nature. Here we have addressed this issue by using single trial statistical "brain reading" of neurophysiological event related (ERP) signatures of conscious perception of visual attributes with different levels of saliency. Behavioral reports were taken at every trial in 4 experiments addressing conscious access to color, luminance, and local phase offset cues. We found that single trial neurophysiological signatures of target presence can be observed around 300 ms at central parietal sites. Such signatures are significantly related with conscious perception, and their probability is related to sensory saliency levels. These findings identify a general neural correlate of conscious perception at the single trial level, since conscious perception can be decoded as such independently of stimulus salience and fluctuations of threshold levels. This approach can be generalized to successfully detect target presence in other individuals.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Event-Related Potentials, P300
  • Female
  • Humans
  • Male
  • Photic Stimulation
  • Subliminal Stimulation*
  • Visual Perception*
  • Young Adult

Grants and funding

This work was supported by the Portuguese Foundation for Science and Technology, grants ID: COMPETE, PEst-C/SAU/UI3282/2011, CENTRO-07-ST24-FEDER-00205, FP7-HEALTH-2013-INNOVATION-1 - 602186 - BRAINTRAINPTDC/SAU-NEU/68483/2006, PIC/IC/82986/2007, PTDC/SAU-ORG/118380 (FCT), and a scholarship to the first author, SFRH/BD/64383/2009, Bial Foundation 132 & 133/2013. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.