Attention and the speed of information processing: posterior entry for unattended stimuli instead of prior entry for attended stimuli

PLoS One. 2013;8(1):e54257. doi: 10.1371/journal.pone.0054257. Epub 2013 Jan 30.

Abstract

Why are nearly simultaneous stimuli frequently perceived in reversed order? The origin of errors in temporal judgments is a question older than experimental psychology itself. One of the earliest suspects is attention. According to the concept of prior entry, attention accelerates attended stimuli; thus they have "prior entry" to perceptive processing stages, including consciousness. Although latency advantages for attended stimuli have been revealed in psychophysical studies many times, these measures (e.g. temporal order judgments, simultaneity judgments) cannot test the prior-entry hypothesis completely. Since they assess latency differences between an attended and an unattended stimulus, they cannot distinguish between faster processing of attended stimuli and slower processing of unattended stimuli. Therefore, we present a novel paradigm providing separate estimates for processing advantages respectively disadvantages of attended and unattended stimuli. We found that deceleration of unattended stimuli contributes more strongly to the prior-entry illusion than acceleration of attended stimuli. Thus, in the temporal domain, attention fulfills its selective function primarily by deceleration of unattended stimuli. That means it is actually posterior entry, not prior entry which accounts for the largest part of the effect.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Attention / physiology*
  • Humans
  • Judgment / physiology*
  • Mental Processes / physiology*
  • Photic Stimulation
  • Reaction Time / physiology
  • Time Perception
  • Visual Perception / physiology

Grants and funding

This research was funded by DFG (http://www.dfg.de/index.jsp) grants SCHA 1515/1-1, 1-2 within the ECRP II Programme of the European Science Foundation and SCHA 1515/1-3. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.