Recent Work on the Nature and Development of Delusions

What are delusions? Examining the typology problem

Delusions are a heterogenous transdiagnostic phenomenon with a higher prevalence in schizophrenia. One of the most fundamental debates surrounding the philosophical understanding of delusions concerns the question about the type of mental state in which reports that we label as delusional are grounded, namely, the typology problem. The formulation of potential answers for this problem seems to have important repercussions for experimental research in clinical psychiatry and the development of psychotherapeutic tools for the treatment of delusions in clinical psychology. Problematically, such alternatives are scattered in the literature, making it difficult to follow the current development and state of the target discussion. This paper offers an updated critical examination of the alternatives to the typology problem currently available in the literature. After clarifying the two main philosophical views underlying the dominant formulation of the debate (interpretivism and functionalism), we follow the usual distinction between doxastic (the idea that delusions are a type of belief) and anti-doxastic views. We then introduce two new sub-distinctions; on the doxastic camp, we distinguish between revisionist and non-revisionist proposals; on the anti-doxastic camp, we distinguish between commonsensical and non-commonsensical anti-doxasticisms. After analyzing the main claims of each view, we conclude with some of the most fundamental challenges that remain open within the discussion. This article is categorized under: Philosophy > Foundations of Cognitive Science Philosophy > Consciousness Philosophy > Psychological Capacities Neuroscience > Cognition.

Do delusions have and give meaning?

Delusions are often portrayed as paradigmatic instances of incomprehensibility and meaninglessness. Here we investigate the relationship between delusions and meaning from a philosophical perspective, integrating arguments and evidence from cognitive psychology and phenomenological psychopathology. We review some of the empirical and philosophical literature relevant to two claims about delusions and meaning: (1) delusions are meaningful, despite being described as irrational and implausible beliefs; (2) some delusions can also enhance the sense that one's life is meaningful, supporting agency and creativity in some circumstances. Delusions are not incomprehensible representations of reality. Rather, they can help make sense of one's unusual experiences and in some circumstances even support one's endeavours, albeit temporarily and imperfectly. Acknowledging that delusions have meaning and can also give meaning to people's lives has implications for our understanding of psychotic symptoms and for addressing the stigma associated with psychiatric conditions.

In defense of the one-factor doxastic account: A phenomenal account of delusions

According to the doxastic model, delusions are beliefs. In the metacognitive model, delusions are imaginings mistaken for beliefs. I argue that endorsement of false second-order beliefs could also create unpleasant dissonance, that mentally healthy people often endorse irrational or conflicting beliefs, and that the lack of delusion-motivated action can be explained by the influence of nonbelief factors on action. The two-factor doxastic model posits irrationality as necessary, and one metric of rationality many scholars employ is whether a response is easily understood by folk psychology. A precedent for folk-psychological acceptance of contextually bizarre beliefs as a result of personal experience can already be found in the lack of imaginative resistance encountered not in response to the impossibilities portrayed in speculative fiction, but in response to the characters' ability to incorporate these occurrences into their mental frameworks, despite them often being at odds with these characters' bedrock understanding of the world.

Delusions beyond beliefs: a critical overview of diagnostic, aetiological, and therapeutic schizophrenia research from a clinical-phenomenological perspective

Delusions are commonly conceived as false beliefs that are held with certainty and which cannot be corrected. This conception of delusion has been influential throughout the history of psychiatry and continues to inform how delusions are approached in clinical practice and in contemporary schizophrenia research. It is reflected in the full psychosis continuum model, guides psychological and neurocognitive accounts of the formation and maintenance of delusions, and it substantially determines how delusions are approached in cognitive-behavioural treatment. In this Review, we draw on a clinical-phenomenological framework to offer an alternative account of delusion that incorporates the experiential dimension of delusion, emphasising how specific alterations to self-consciousness and reality experience underlie delusions that are considered characteristic of schizophrenia. Against that backdrop, we critically reconsider the current research areas, highlighting empirical and conceptual issues in contemporary delusion research, which appear to largely derive from an insufficient consideration of the experiential dimension of delusions. Finally, we suggest how the alternative phenomenological approach towards delusion could offer new ways to advance current research and clinical practice.

Looking into a Deluded Brain through a Neuroimaging Lens

Delusions are irrational, tenacious, and incorrigible false beliefs that are the most common symptom of a range of brain disorders including schizophrenia, Alzheimer's, and Parkinson's disease. In the case of schizophrenia and other primary delusional disorders, their appearance is often how the disorder is first detected and can be sufficient for diagnosis. At this time, not much is known about the brain dysfunctions leading to delusions, and hindering our understanding is that the complexity of the nature of delusions, and their very unique relevance to the human experience has hampered elucidation of their underlying neurobiology using either patients or animal models. Advances in neuroimaging along with improved psychiatric and cognitive modeling offers us a new opportunity to look with more investigative power into the deluded brain. In this article, based on data obtained from neuroimaging studies, we have attempted to draw a picture of the neural networks involved when delusion is present and evaluate whether different manifestations of delusions engage different regions of the brain.

Are clinical delusions adaptive?

Delusions are symptoms of psychiatric disorders such as schizophrenia and dementia. By and large, delusions are characterized by their behavioral manifestations and defined as irrational beliefs that compromise good functioning. In this overview paper, we ask whether delusions can be adaptive notwithstanding their negative features. Can they be a response to a crisis rather than the source of the crisis? Can they be the beginning of a solution rather than the problem? Some of the psychological, psychiatric, and philosophical literature has recently suggested that they can. We consider different types of delusions and different ways in which they can be considered as adaptive: psychologically (e.g., by increasing wellbeing, purpose in life, intrapsychic coherence, or good functioning) and biologically (e.g., by enhancing genetic fitness). Although further research is needed to map the costs and benefits of adopting and maintaining delusional beliefs, a more nuanced picture of the role of delusions in people's lives has started to emerge.

This article is categorized under:

Philosophy > Representation

Philosophy > Knowledge and Belief

Neuroscience > Cognition