The First Deluded by Experience Workshop Report

In today's post Harriet Stuart (MRes student in Philosophy at the University of Birmingham) reports on the Deluded by Experience workshop on delusion formation, held online on 12th and 13th July 2021. This was the first workshop of the AHRC funded Project Deluded by Experience and was organised by Ema Sullivan-Bissett and Paul Noordhof.

Poster of the event

Day one started with Kengo Miyazono who presented ‘Salience and Affordance in Schizophrenia’. Kengo proposed a revision of the Aberrant Salience Hypothesis (Kapur, 2003). He claimed that “salience” can be analysed in terms of affordance; an object X is “salient” if and only if X “affords” attention. The altered experience in schizophrenia involves some aberrant salience which is caused by relatively strengthened attentional affordances owing to damage to top-down suppression mechanisms.

Kengo Miyazono

Then Sam Wilkinson presented ‘Agent Representations as Generative Models: The case of Delusional Misidentification’. Sam suggested that delusional misidentification can be explained by errors in the management of mental files whereby mental files are a metaphor for singular (agent) representations. Management of files is to be thought of as a generative model whereby hypotheses are hierarchically arranged and selected based on how well they minimise prediction error.

Sam Wilkinson

Closing day one was Carolina Flores, speaking on ‘The Intelligibility of Schizophrenia’. Carolina introduced her notion of epistemic styles: a unified way of interacting with evidence that express (aspects of) a set of epistemic parameters. The central claim was that the cognitive biases implicated in delusion formation in schizophrenia constitute a distinctive epistemic style. Everyone ordinarily adopts an epistemic style but subjects with schizophrenia can set up their parameters in one specific, extreme way. However, this is not qualitatively different from everyday reasoning. Importantly, the view suggests that intelligibility and rationality should be separated.

Carolina Flores

Day two started with Paul Noordhof and Ema Sullivan-Bissett with their talk ‘The Everyday Irrationality of Monothematic Delusions’. Ema argued that the examination of non-clinical paranormal beliefs and monothematic delusions shows no significant difference that would warrant positing a second irrationality (in addition to the anomalous experience) to explain the latter. Paul went on to claim that monothematic delusions can display features of everyday motivated irrationalities like wishful thinking/weak self-deception and strong self-deception, supporting their claim that delusions are closer to everyday irrationalities than typically thought.

Ema Sullivan-Bissett

Next up was Clara Humpston presenting ‘Isolated by Oneself: Solipsistic Delusions in Schizophrenia’. Clara argued that self-disturbance characterised by paradoxical states of thought is the central background to ‘ontologically impossible’ experiences, which sometimes lead to solipsistic delusions, in schizophrenia. Solipsistic delusions retain the centrality of the self during grave self-disturbance; it is the delusion that ‘adopts’ the patient rather than the other way around, what Clara called ‘autophagy of the self’ or ‘self-eating-self’.

Clara Humpston

Lastly, Dan Williams spoke on ‘Computational Psychiatry and the Social Focus of Delusions’. Dan argued that insights from a predictive coding account and a social account of delusions were possible to integrate without positing the social element as an extra, clinically significant factor. He claimed that the domain-specific content of delusions result from the interaction of a global information-processing dysfunction with various social factors, therefore explaining why delusions tend to cluster around a small number of themes.

Dan Williams