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How unrealistic optimism is maintained in the face of reality

Nature Neuroscience volume 14, pages 14751479 (2011) | Download Citation


Unrealistic optimism is a pervasive human trait that influences domains ranging from personal relationships to politics and finance. How people maintain unrealistic optimism, despite frequently encountering information that challenges those biased beliefs, is unknown. We examined this question and found a marked asymmetry in belief updating. Participants updated their beliefs more in response to information that was better than expected than to information that was worse. This selectivity was mediated by a relative failure to code for errors that should reduce optimism. Distinct regions of the prefrontal cortex tracked estimation errors when those called for positive update, both in individuals who scored high and low on trait optimism. However, highly optimistic individuals exhibited reduced tracking of estimation errors that called for negative update in right inferior prefrontal gyrus. These findings indicate that optimism is tied to a selective update failure and diminished neural coding of undesirable information regarding the future.

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We thank S. Fleming for assistance with analysis, P. Dayan for discussion, and T. Behrens, D. Schiller, Q. Huys, J. Winston, B. De Martino, S. Fleming, S. Bengtsson, K. Wunderlich, H. Heekeren, S. Kennerley and M. Guitart-Masip for comments on a previous version of this manuscript. This study was supported by a Wellcome Trust Program grant to R.J.D., a British Academy Postdoctoral Fellowship to T.S., and a German Academic Exchange Service (DAAD) scholarship to C.W.K.

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Author notes

    • Tali Sharot
    •  & Christoph W Korn

    These authors contributed equally to this work.


  1. Wellcome Trust Centre for Neuroimaging, University College London, London, UK.

    • Tali Sharot
    •  & Raymond J Dolan
  2. Department of Education and Psychology, Freie Universität Berlin, Berlin, Germany.

    • Christoph W Korn
  3. School of Mind and Brain, Humboldt Universität zu Berlin, Berlin, Germany.

    • Christoph W Korn


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T.S. conceived the study. T.S. and C.W.K. designed the study, developed stimuli, and gathered and analyzed behavioral and fMRI data. T.S., C.W.K. and R.J.D. interpreted the data and wrote the paper.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Tali Sharot.

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    Supplementary Results, Supplementary Table 1, Supplementary Figure 1, List of Stimuli, and Behavioral Studies 1 and 2

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