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2 - Visions

Published online by Cambridge University Press:  17 September 2021

By
Paul Fletcher
Edited by
Andrew Fabian ,
Janet Gibson ,
Mike Sheppard  and
Simone Weyand
With contributions by
Andrew Blake ,
Carolin Crawford ,
Paul Fletcher ,
Sophie Hackford ,
Anya Hurlbert ,
Dan-Eric Nilsson  and
Carlo Rovelli
Andrew Fabian
Affiliation:
University of Cambridge
Janet Gibson
Affiliation:
Darwin College, Cambridge
Mike Sheppard
Affiliation:
University of Cambridge
Simone Weyand
Affiliation:
University of Cambridge
Andrew Blake
Affiliation:
Samsung AI Research Centre
Carolin Crawford
Affiliation:
University of Cambridge
Paul Fletcher
Affiliation:
University of Cambridge
Sophie Hackford
Affiliation:
Wired Magazine
Anya Hurlbert
Affiliation:
Newcastle University
Dan-Eric Nilsson
Affiliation:
Lunds Universitet, Sweden
Carlo Rovelli
Affiliation:
International Centre for Theoretical Physics
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Summary

The brain strives to become a model of the world in which it must survive. It is often more important for it to be functional and efficient than it is to be factually correct. Indeed, there are numerous instances in which it seems to favour usefulness over accuracy, expectation over actuality. This has led many to conclude that even normal perception has a constructive or hallucinatory quality. In extremis, under the influence of fatigue, fear, illness or drugs, an entire reality may be created, one that seems to conflict with the reality accepted by those around us. This condition, known as psychosis, offers us important glimpses into the mechanisms of the mind and the many ways in which they may be altered.

Keywords

visual perceptionillusionhallucinationvisionspsychosisneurology of visionmental modelspredictioninference
Type
Chapter
Information
Vision , pp. 33 - 56
Publisher: Cambridge University Press
Print publication year: 2021

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References

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Conant, R. C., and Ashby, W. R. Every good regulator of a system must be a model of that system. Int. J. Systems Sci. 1970; 1(2): 89–97.CrossRefGoogle Scholar
Teufel, C., Subramaniam, N., Dobler, V., Perez, J., Finnemann, J. et al. Shift toward prior knowledge confers a perceptual advantage in early psychosis and psychosis-prone healthy individuals. Proc. Natl Acad. Sci. USA 2015; 112(43): 13401–13406.Google Scholar
Teufel, C., Dakin, S. C., and Fletcher, P. C. Prior object-knowledge sharpens properties of early visual feature-detectors. Sci Rep. 2018; 8(1): 10853.Google Scholar
Srinivasan, M. V., Laughlin, S. B., and Dubs, A. Predictive coding: A fresh view of inhibition in the retina. Proc. R. Soc. Lond. B Biol. Sci. 1982; 216(1205): 427–459.Google Scholar
Harrison, C. W. Experiments with Linear Prediction in Television. Bell Syst. Tech. J. 1952; 31(July): 764–783.CrossRefGoogle Scholar

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