Delusions and prediction error

Abstract

Different empirical and theoretical traditions approach delusions differently. This chapter is about how cognitive neuroscience-the practice of studying the brain to draw conclusions about the mind-has been applied to the problem of belief and delusion. In particular, the focus is on a particular bridging theory, that of predictive coding. This theory holds that the brain contains a model of the world (and the self as an agent in that world). It uses that model to make predictions in order to adapt to the environment. Errors in those predictions can garner belief updating or be ignored, depending on how each prediction error response sustains adaptive fitness. The discussion will cover how delusions might arise and be maintained under the influence of aberrant prediction errors and what psychological and neural mechanisms of prediction error processing pertain to delusions, comparing and contrasting the theory with other prominent theories of delusions. The conclusion is that the single factor, prediction error account gives a parsimonious account of delusions that generates novel predictions about how best to treat delusions and incorporates numerous biological, clinical and phenomenological data regarding delusions.