Matthew Broome
Matthew is an academic psychiatrist at the University of Oxford and Consultant Psychiatrist to the Warneford Hospital, Oxford Health NHS Foundation Trust.
With colleagues, Matthew co-founded the Maudsley Philosophy Group in 2002
Supervisors: Philippa Garety and Philip McGuire
With colleagues, Matthew co-founded the Maudsley Philosophy Group in 2002
Supervisors: Philippa Garety and Philip McGuire
less
InterestsView All (60)
Uploads
Books by Matthew Broome
Papers by Matthew Broome
Is the prediction-error theory a rival to the two-factor theory? Prediction-error theorists tend to be critical about the two-factor theory and present their views as an alternative to it. Fletcher and Frith wrote, on the two-factor theory: “symptoms reflecting false perception and false beliefs are so intertwined in schizophrenia that a theory relying on coincidental damage seems very unlikely.” (Fletcher & Frith 2009, 51) Again, Corlett and colleagues argue that positing two factors is redundant because “a single deficit in Bayesian inference is able to explain more of what we know about the interactions between perception and belief-based expectation, the neurobiology of the delusions that occur in schizophrenia and the maintenance of delusions in the face of contradictory evidence.” (Corlett et al. 2010, 357)
In this chapter, we examine the relationship between the two-factor theory and the prediction-error theory in some detail. Our view is that the prediction-error theory does not have to be understood as a rival to the two-factor theory. We do not deny that there are some important differences between them. However, those differences are not as significant as they have been presented in the literature. Moreover, the core ideas of the prediction-error theory may be incorporated into the two-factor framework. For instance, the aberrant prediction-error signal that is posited by prediction-error theorists can be (or underlie) the first factor contributing to the formation of some delusions, and help explain the content of those delusions. Alternatively, the aberrant prediction-error signal can be (or underlie) the second factor, and help explain why the delusion is adopted and maintained.
Is the prediction-error theory a rival to the two-factor theory? Prediction-error theorists tend to be critical about the two-factor theory and present their views as an alternative to it. Fletcher and Frith wrote, on the two-factor theory: “symptoms reflecting false perception and false beliefs are so intertwined in schizophrenia that a theory relying on coincidental damage seems very unlikely.” (Fletcher & Frith 2009, 51) Again, Corlett and colleagues argue that positing two factors is redundant because “a single deficit in Bayesian inference is able to explain more of what we know about the interactions between perception and belief-based expectation, the neurobiology of the delusions that occur in schizophrenia and the maintenance of delusions in the face of contradictory evidence.” (Corlett et al. 2010, 357)
In this chapter, we examine the relationship between the two-factor theory and the prediction-error theory in some detail. Our view is that the prediction-error theory does not have to be understood as a rival to the two-factor theory. We do not deny that there are some important differences between them. However, those differences are not as significant as they have been presented in the literature. Moreover, the core ideas of the prediction-error theory may be incorporated into the two-factor framework. For instance, the aberrant prediction-error signal that is posited by prediction-error theorists can be (or underlie) the first factor contributing to the formation of some delusions, and help explain the content of those delusions. Alternatively, the aberrant prediction-error signal can be (or underlie) the second factor, and help explain why the delusion is adopted and maintained.