Format

Send to

Choose Destination
Curr Biol. 2018 Oct 8;28(19):3128-3135.e8. doi: 10.1016/j.cub.2018.07.052. Epub 2018 Sep 13.

Confirmation Bias through Selective Overweighting of Choice-Consistent Evidence.

Author information

1
Department of Neurophysiology & Pathophysiology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany. Electronic address: bharathchandra.talluri@gmail.com.
2
Department of Neurophysiology & Pathophysiology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; Department of Psychology, University of Amsterdam, 1018 WS Amsterdam, the Netherlands.
3
Department of Neurophysiology & Pathophysiology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
4
School of Psychology, Tel-Aviv University, 69989 Ramat-Aviv, Tel-Aviv, Israel; Sagol School of Neuroscience, Tel-Aviv University, 69989 Ramat-Aviv, Tel-Aviv, Israel.
5
Department of Neurophysiology & Pathophysiology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; Department of Psychology, University of Amsterdam, 1018 WS Amsterdam, the Netherlands. Electronic address: t.donner@uke.de.

Abstract

People's assessments of the state of the world often deviate systematically from the information available to them [1]. Such biases can originate from people's own decisions: committing to a categorical proposition, or a course of action, biases subsequent judgment and decision-making. This phenomenon, called confirmation bias [2], has been explained as suppression of post-decisional dissonance [3, 4]. Here, we provide insights into the underlying mechanism. It is commonly held that decisions result from the accumulation of samples of evidence informing about the state of the world [5-8]. We hypothesized that choices bias the accumulation process by selectively altering the weighting (gain) of subsequent evidence, akin to selective attention. We developed a novel psychophysical task to test this idea. Participants viewed two successive random dot motion stimuli and made two motion-direction judgments: a categorical discrimination after the first stimulus and a continuous estimation of the overall direction across both stimuli after the second stimulus. Participants' sensitivity for the second stimulus was selectively enhanced when that stimulus was consistent with the initial choice (compared to both, first stimuli and choice-inconsistent second stimuli). A model entailing choice-dependent selective gain modulation explained this effect better than several alternative mechanisms. Choice-dependent gain modulation was also established in another task entailing averaging of numerical values instead of motion directions. We conclude that intermittent choices direct selective attention during the evaluation of subsequent evidence, possibly due to decision-related feedback in the brain [9]. Our results point to a recurrent interplay between decision-making and selective attention.

KEYWORDS:

attention; computational model; decision-making; human; numerical cognition; perception; psychophysics

PMID:
30220502
DOI:
10.1016/j.cub.2018.07.052
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center