The silent period of evidence integration in fast decision making

PLoS One. 2013;8(1):e46525. doi: 10.1371/journal.pone.0046525. Epub 2013 Jan 21.

Abstract

In a typical experiment on decision making, one out of two possible stimuli is displayed and observers decide which one was presented. Recently, Stanford and colleagues (2010) introduced a new variant of this classical one-stimulus presentation paradigm to investigate the speed of decision making. They found evidence for "perceptual decision making in less than 30 ms". Here, we extended this one-stimulus compelled-response paradigm to a two-stimulus compelled-response paradigm in which a vernier was followed immediately by a second vernier with opposite offset direction. The two verniers and their offsets fuse. Only one vernier is perceived. When observers are asked to indicate the offset direction of the fused vernier, the offset of the second vernier dominates perception. Even for long vernier durations, the second vernier dominates decisions indicating that decision making can take substantial time. In accordance with previous studies, we suggest that our results are best explained with a two-stage model of decision making where a leaky evidence integration stage precedes a race-to-threshold process.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Decision Making / physiology*
  • Female
  • Humans
  • Perception / physiology
  • Physical Stimulation
  • Time Factors

Grant support

Johannes Rüter is funded by the Swiss National Science Foundation (SNF) project No. 320030-119736 “The dynamics of feature fusion”. Michael H. Herzog and Wulfram Gerstner receive support from the SNF Sinergia project CRSIK0-122697 “State representation in reward based learning - from spiking neuron models to psychophysics”. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.