Closing the gates to consciousness: distractors activate a central inhibition process

J Cogn Neurosci. 2012 Jun;24(6):1294-304. doi: 10.1162/jocn_a_00177. Epub 2011 Dec 20.

Abstract

The paradigm of distractor-induced blindness has previously been used to track the transition from unconscious to conscious visual processing. In a variation of this paradigm used in this study, participants (n = 13) had to detect an orientation change of tilted bars (target) embedded in a dynamic random pattern; the onset of the target was signaled by the presentation of a color cue. Occasional orientation changes preceding the cue served as distractors and severely impaired the target's detection. ERPs showed that a frontal negativity was cumulatively activated by the distractors, and early sensory components were not affected. In a control condition, the target was defined by a coherent motion of the bars. Orientation changes preceding the motion target did not affect its detection, and the frontal suppression process was not observed. However, we obtained a significant reduction of the sensory components. The data support the notion that distractors that share the target's features trigger a cumulative inhibition process preventing the conscious representation of the inhibited features. Explorative source modeling suggests that this process originates in the pFC. A top-down modulation of sensory processing could not be observed.

Publication types

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

MeSH terms

  • Adult
  • Consciousness / physiology*
  • Female
  • Humans
  • Male
  • Neural Inhibition / physiology*
  • Orientation / physiology
  • Photic Stimulation / methods*
  • Psychomotor Performance / physiology*
  • Young Adult