Send to

Choose Destination
J Neurosci. 2018 Sep 5;38(36):7901-7911. doi: 10.1523/JNEUROSCI.0716-18.2018. Epub 2018 Aug 6.

Updating Beliefs under Perceived Threat.

Author information

Affective Brain Laboratory, Experimental Psychology, University College London, London WC1H 0AP, United Kingdom,
Princeton Neuroscience Institute, Princeton University, Princeton, New Jersey 08540, and.
Department of Experimental Psychology, University of Oxford, Oxford OX2 6HG.
Affective Brain Laboratory, Experimental Psychology, University College London, London WC1H 0AP, United Kingdom.
Department of Psychology, University of Sheffield, Sheffield S10 2TP, United Kingdom.


Humans are better at integrating desirable information into their beliefs than undesirable information. This asymmetry poses an evolutionary puzzle, as it can lead to an underestimation of risk and thus failure to take precautionary action. Here, we suggest a mechanism that can speak to this conundrum. In particular, we show that the bias vanishes in response to perceived threat in the environment. We report that an improvement in participants' tendency to incorporate bad news into their beliefs is associated with physiological arousal in response to threat indexed by galvanic skin response and self-reported anxiety. This pattern of results was observed in a controlled laboratory setting (Experiment I), where perceived threat was manipulated, and in firefighters on duty (Experiment II), where it naturally varied. Such flexibility in how individuals integrate information may enhance the likelihood of responding to warnings with caution in environments rife with threat, while maintaining a positivity bias otherwise, a strategy that can increase well-being.SIGNIFICANCE STATEMENT The human tendency to be overly optimistic has mystified scholars and lay people for decades: How could biased beliefs have been selected over unbiased beliefs? Scholars have suggested that although the optimism bias can lead to negative outcomes, including financial collapse and war, it can also facilitate health and productivity. Here, we demonstrate that a mechanism generating the optimism bias, namely asymmetric information integration, evaporates under threat. Such flexibility could result in enhanced caution in dangerous environments while supporting an optimism bias otherwise, potentially increasing well-being.


anxiety; information processing; optimism; risk; stress; threat

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center