Philosophy of Mind and Psychology Reading Group -- The Predictive Mind chapter 7

Kengo Miyazono

Welcome to the Philosophy of Mind and Psychology Reading Group hosted by the Philosophy@Birmingham blog. This month, Kengo Miyazono, post-doctoral research fellow at the University of Birmingham, introduces chapter 7 of Jakob Hohwy's The Predictive Mind (OUP, 2013).


Chapter 7 - Precarious Prediction
Presented by Kengo Miyazono

In chapter seven, Hohwy describes the ways in which perceptual inference is tuned in order to represent the world correctly and the ways in which it goes wrong.

The chapter discusses many different issues, but the central idea is that maintaining the "balance between trusting the sensory input and consequently keeping on sampling the world, versus distrusting the sensory input and instead relying more on one's prior beliefs" (146) is crucial in the successful operation of perceptual inference. Maintaining it is not a trivial task. And, the failure of the maintenance might be responsible for pathological conditions such as delusions or autism.

In principle, the prediction errors that are expected to be precise are allowed to drive revisions of prior beliefs higher up the hierarchy, while the prediction errors that are expected to be imprecise are not allowed to do so. Ideally, we expect high precision in predictions errors and, hence, allow them to drive belief revisions when they are trustworthy and expect low precision in prediction errors and, hence, do not allow them to drive belief revisions when they are not.

But, the process can go wrong. A possibility is that some people expect sensory prediction errors to be much less precise than they actually are. Hohwy suggests that this is what is happening in people with delusions; "a persistent, exaggerated expectation for noise and uncertainty would lead to imprecise sensory prediction errors mediated by low gain on sensory input and heightened reliance on top-down priors. 

Agent-Responsibility and Psychiatric Diagnosis

In this post PhD student Benjamin Costello talks about his research. Ben is supervised by Lisa Bortolotti and Iain Law, and soon Hanna Pickard will join his supervisory team too.

Benjamin Costello

My research is concerned with the relationship between mental illness, involuntary hospitalisation, and the sequencing of actions and personal identity. My thesis can be broken-down into the following four areas:

Moral Sequencing: Accounting for the nature of and changes in agency, personality, and identity. I am in the process of examining the nature of agency, personality, and identity, ascertaining the link between them, and determining how these alter or change. I am devising new models of moral sequences that can be used to track the actions of agents, which account for changes in personality/identity, and can help ascertain if and when an intervention is justifiable. I argue that these models have ramifications for how personality disorders and dissociative disorders should be discussed and used both in psychiatry and in the DSM/ICD. By constructing these models, I hope to: (a) establish a relationship between agency and personality/identity; (b) assess the dangerousness of an individual and the need to intervene; (c) gauge the extent to which an identity-change undermines agent-responsibility; and (d) elucidate how detentions based solely on the presence of a mental disorder is morally unjustifiable.

The criteria for being labelled ‘dangerous’ and ascertaining when intervention is justifiable. With the aim of positively influencing the way mental disorders are perceived, I aim to debunk the idea that the mentally ill are ipso facto dangerous (either to themselves or to others). Within the models of moral sequencing, I aim to incorporate a method of ascertaining the justifiability of intervening to assess the dangerousness of agents and prevent dangerous people from harming by constructing a “quick but accurate” hybrid decision theory that amalgamates a calculated decision-making mechanism (based on Bayesian probability) with a fast-and-frugal mechanism (based on Damasio’s Somatic Marker Hypothesis).

Emotion and Consciousness: Damasio's Hypothesis

Isaura Peddis

This week PhD student Isaura Peddis writes about her research. Isaura is supervised by Iain Law and Lisa Bortolotti in the Philosophy Department, and her thesis is provisionally entitled 'The Importance of Empathy'.


I am a first year PhD student interested in emotions, particularly in empathy. In the last couple of months, I have researched the cognitive and feeling theories of emotions. During my research, I came across Damasio’s theory of emotions, which I will shortly summarise here. In my opinion, his idea well introduces the important role of consciousness for emotions, as it is a key factor for empathy and any actions deriving from this feeling. This is a topic that I will particularly focus on in my dissertation.

Antonio Damasio thinks that, to feel an emotion, an organism must satisfy three prerequisites. Firstly, the organism has to have a body and represent it through its mind; this excludes plants which do not have neural patterns to process the reaction of the stimuli like a brain would. Secondly, the organism has to have a nervous system able to map body structures and body states and transform this information into a mental representation. Thirdly, the brain creates the neural patterns that generate emotions through a constant interaction with the objects that provoke those emotions (Damasio, 2004: 109-110). Therefore, in simple words, an emotion is a change that happens into our body and is trigged by the interaction that an organism has with a particular object. Through our sensory perception and thoughts, we elaborate a mental representation of the relation between the body and the object, and this causes the bodily changes that we feel and normally label as emotions.

Do Delusions Have Epistemic Value?

Kengo Miyazono

In this post Kengo Miyazono, post-doctoral researcher at the University of Birmingham Philosophy Department, summarises a paper he presented it at the 88th Joint Session of the Aristotelian Society and Mind Association in Cambridge earlier this month. The paper “Do delusions have any epistemic value?”, co-authored by Kengo and Lisa Bortolotti was presented in the open session.

Delusional beliefs are false in most cases. And, probably, they are unjustified according any interesting accounts of epistemic justification. However, we believe that there are some positive things we can say about epistemic status of delusional beliefs. The aim of the paper (or, strictly speaking, the aim of the longer paper upon which the presented paper is based) is to defend two claims about the epistemic status of delusional beliefs. The claims correspond to two kinds of epistemic evaluations; consequentialist and deontological evaluations. First, delusions can have some good epistemic consequences that are at least indirectly related to the acquisition of true beliefs. Second, people with delusions are not epistemically blameworthy for their delusional beliefs.