Electrophysiological evidence of the capture of visual attention

J Cogn Neurosci. 2006 Apr;18(4):604-13. doi: 10.1162/jocn.2006.18.4.604.

Abstract

We investigated the ability of salient yet task-irrelevant stimuli to capture attention in two visual search experiments. Participants were presented with circular search arrays that contained a highly salient distractor singleton defined by color and a less salient target singleton defined by form. A component of the event-related potential called the N2pc was used to track the allocation of attention to lateralized positions in the arrays. In Experiment 1, a lateralized distractor elicited an N2pc when a concurrent target was presented on the vertical meridian and thus could not elicit lateralized components such as the N2pc. A similar distractor-elicited N2pc was found in Experiment 2, which was conducted to rule out certain voluntary search strategies. Additionally, in Experiment 2 both the distractor and the target elicited the N2pc component when the two stimuli were presented on opposite sides of the search array. Critically, the distractor-elicited N2pc preceded the target-elicited N2pc on these trials. These results demonstrate that participants shifted attention to the target only after shifting attention to the more salient but task-irrelevant distractor. This pattern of results is in line with theories of attention in which stimulus-driven control plays an integral role.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Attention / physiology*
  • Color Perception / physiology*
  • Electroencephalography / methods
  • Evoked Potentials, Visual / physiology*
  • Female
  • Functional Laterality / physiology
  • Humans
  • Male
  • Pattern Recognition, Visual / physiology*
  • Photic Stimulation / methods
  • Reaction Time / physiology