Confirmation bias in the utilization of others’ opinion strength

Abstract

Humans tend to discount information that undermines past choices and judgements. This confirmation bias has significant impact on domains ranging from politics to science and education. Little is known about the mechanisms underlying this fundamental characteristic of belief formation. Here, we report a novel mechanism underlying the confirmation bias. Specifically, we provide evidence for a failure to use the strength of others' disconfirming opinions to alter confidence in judgements, but adequate use when opinions are confirmatory. This bias is related to reduced neural sensitivity to the strength of others' opinions in the posterior medial prefrontal cortex (pMFC) when opinions are disconfirming. Our results demonstrate that existing judgements alter the neural representation of information strength, leaving the individual less likely to alter opinions in the face of disagreement.

Confidence drives a neural confirmation bias

“…A confirmation bias in the current experiment was observed in low-level perceptual decisions with limited emotional or cognitive content, suggesting that choice-induced biases in evidence accumulation represent a core principle of neural information processing 8,33 . In most real-world decisions, additional motivational 34 and social 35 influences (e.g. not revising a decision in order to appear self-consistent) are presumably also in play.…”

Belief updating in bipolar disorder predicts time of recurrence

“…learning that the likelihood of receiving a job offer is greater than expected) than negative information (e.g. learning it is lower than expected; Kappes et al, 2020 ; Kuzmanovic et al, 2016 ; Ma et al, 2016 ; Moutsiana et al, 2015 ; Sharot et al, 2011 ). Such asymmetry in valence-dependent belief updating leads to optimistic beliefs ( Sharot et al, 2011 ).…”

What Is the Function of Confirmation Bias?

“…This is not only because subjects can often directly influence political affairs via voting, running as a candidate, campaigning, etc. It is also because subjects who are highly confident about their political beliefs are more likely to be able to convince other people of them too (Kappes et al 2020). And the more widespread a political conviction in a population, the higher the probability that the population will adopt political structures that shape reality in line with it (Jost et al 2003;Ordabayeva and Fernandes 2018).…”

“…For subjects have a keen interest in reality corresponding to their ideological conceptions. Since the latter are shaping social reality via their impact on behavior and are more effective in doing so the more convinced people are about them (Kappes et al 2020), it is to be expected that when it comes to ideological propositions in like-minded groups, confirmation bias is more pronounced. And, as noted, the resulting group polarization itself can then be adaptive in strengthening the realitymatching process.…”