Nature Mental Health
June 1, 2026
George E. Chapman, Philip R. Corlett, Stephen M Fleming et al.
Delusions are a key feature of psychotic disorders, yet their fixity remains underexplored. Here, the authors propose a refined vocabulary for delusion fixity, review influencing factors, and present a working model. The Review calls for interdisciplinary longitudinal studies that could enhance the understanding of delusion fixity and facilitate the advancement of therapeutic strategies. Fixed,...
Brain : a journal of neurology
May 13, 2025
Veith Weilnhammer, Marcus Rothkirch, Deniz Yilmaz et al.
11 citations
Perception integrates external sensory signals with internal predictions that reflect prior knowledge about the world. Previous research suggests that this integration is governed by slow alternations between an external mode, driven by sensory signals, and an internal mode, shaped by prior knowledge. Using a double-blind, placebo-controlled, cross-over experiment in healthy human participants,...
Am J Psychiatry
March 26, 2025
Philip R. Corlett, Kurt M. Fraser
9 citations
" captured the attention of clinicians and cognitive and behavioral neuroscientists. It has become the de facto way of talking about delusion formation in labs and clinics. Here, evidence for this theory is critically evaluated in consideration of evolving data since its publication. A particular focus is placed on its specific predictions regarding the neural and behavioral loci of dopamine...
Commun Psychol
August 1, 2024
Hugh McGovern, Hilary J Grimmer, Manoj K. Doss et al.
48 citations
Psychedelics are recognised for their potential to re-orient beliefs. We propose a model of how psychedelics can, in some cases, lead to false insights and thus false beliefs. We first review experimental work on laboratory-based false insights and false memories. We then connect this to insights and belief formation under psychedelics using the active inference framework. We propose that...
Schizophr Bull
February 1, 2023
Tanya M Luhrmann, Ben Alderson-Day, Ann Chen et al.
AbstractThere are communities in which hearing voices frequently is common and expected, and in which participants are not expected to have a need for care. This paper compares the ideas and practices of these communities. We observe that these communities utilize cultural models to identify and to explain voice-like events—and that there are some common features to these models across...
ACS Chemical Neuroscience
August 24, 2022
Manoj K. Doss, Frederick S. Barrett, Philip R. Corlett
21 citations
A recent paper in Nature Medicine found that psilocybin therapy in patients with depression decreased brain network modularity (measured with task-free functional magnetic resonance imaging), an effect supposedly not found with the selective serotonin reuptake inhibitor S-citalopram. This decrease in network modularity also correlated with depression. Here, we raise several issues with this...
April 28, 2022
Manoj K. Doss, Frederick S. Barrett, Philip R. Corlett
1 citation
preprint
Here we raise issues in Daws et al. (2022) published in Nature Medicine.
September 15, 2021
Hugh McGovern, Pantelis Leptourgos, Brendan Hutchinson et al.
4 citations
preprint
Renewed interest in psychedelics has reignited the debate about whether and how they change human beliefs. In both the clinical and social-cognitive domains, psychedelic consumption may be accompanied by profound, and sometimes lasting, belief changes. We review these changes and their possible underlying mechanisms. Rather than inducing de novo beliefs, we argue psychedelics may instead change...
Schizophrenia Bulletin
August 5, 2020
Pantelis Leptourgos, Martin Fortier-Davy, Robin Carhart-Harris et al.
88 citations
Abstract The recent renaissance of psychedelic science has reignited interest in the similarity of drug-induced experiences to those more commonly observed in psychiatric contexts such as the schizophrenia-spectrum. This report from a multidisciplinary working group of the International Consortium on Hallucinations Research (ICHR) addresses this issue, putting special emphasis on hallucinatory...
Journal of Abnormal Psychology
August 1, 2020
P. Corlett, Aprajita Mohanty, A. MacDonald
The predictive processing framework (PPF) attempts to tackle deep philosophical problems, including how the brain generates consciousness, how our bodies influence cognition, and how cognition alters perception. As such, it provides a zeitgeist that incorporates concepts from physics, computer science, mathematics, artificial intelligence, economics, psychology and neuroscience, leveraging and,...
Schizophrenia Bulletin
August 8, 2018
Tanya M Luhrmann, Ben Alderson-Day, Vaughan Bell et al.
74 citations
That trauma can play a significant role in the onset and maintenance of voice-hearing is one of the most striking and important developments in the recent study of psychosis. Yet the finding that trauma increases the risk for hallucination and for psychosis is quite different from the claim that trauma is necessary for either to occur. Trauma is often but not always associated with...
Biol Psychiatry
May 25, 2018
Philipp Sterzer, Rick A. Adams, Paul Fletcher et al.
901 citations
Fueled by developments in computational neuroscience, there has been increasing interest in the underlying neurocomputational mechanisms of psychosis. One successful approach involves predictive coding and Bayesian inference. Here, inferences regarding the current state of the world are made by combining prior beliefs with incoming sensory signals. Mismatches between prior beliefs and incoming...
PLoS One
June 12, 2013
Philip R. Corlett, Victoria C. Cambridge, Jennifer M. Gardner et al.
104 citations
Delusions are the persistent and often bizarre beliefs that characterise psychosis. Previous studies have suggested that their emergence may be explained by disturbances in prediction error-dependent learning. Here we set up complementary studies in order to examine whether such a disturbance also modulates memory reconsolidation and hence explains their remarkable persistence. First, we...
Cerebral Cortex
November 29, 2012
John D. Murray, Alan Anticevic, Mark G. Gancsos et al.
278 citations
Excitation-inhibition balance (E/I balance) is a fundamental property of cortical microcircuitry. Disruption of E/I balance in prefrontal cortex is hypothesized to underlie cognitive deficits observed in neuropsychiatric illnesses such as schizophrenia. To elucidate the link between these phenomena, we incorporated synaptic disinhibition, via N-methyl-D-aspartate receptor perturbation on...
Proceedings of the National Academy of Sciences
September 25, 2012
Alan Anticevic, Mark G. Gancsos, John D. Murray et al.
260 citations
Glutamatergic neurotransmission mediated by N-methyl-d-aspartate (NMDA) receptors is vital for the cortical computations underlying cognition and might be disrupted in severe neuropsychiatric illnesses such as schizophrenia. Studies on this topic have been limited to processes in local circuits; however, cognition involves large-scale brain systems with multiple interacting regions. A prominent...
Cogn Neuropsychiatry
February 6, 2011
James W. Moore, Danielle C. Turner, Philip R. Corlett et al.
64 citations
INTRODUCTION: Aberrant experience of agency is characteristic of schizophrenia. An understanding of the neurobiological basis of such experience is therefore of considerable importance for developing successful models of the disease. We aimed to characterise the effects of ketamine, a drug model for psychosis, on sense of agency (SoA). SoA is associated with a subjective compression of the...
Biological Psychiatry
2011
H. Morgan, D. Turner, P. Corlett et al.
Background Our sense of body ownership is profound and familiar, yet it may be misleading. In the rubber-hand illusion, synchronous tactile and visual stimulation lead to the experience that a rubber hand is actually one's own. This illusion is stronger in schizophrenia. Given the evidence that ketamine, a noncompetitive N-methyl-D-aspartate antagonist reproduces symptoms of schizophrenia, we...
Psychopharmacology
May 27, 2009
Philip R. Corlett, Chris Frith, Paul C. Fletcher
392 citations
INTRODUCTION: Various experimental manipulations, usually involving drug administration, have been used to produce symptoms of psychosis in healthy volunteers. Different drugs produce both common and distinct symptoms. A challenge is to understand how apparently different manipulations can produce overlapping symptoms. We suggest that current Bayesian formulations of information processing in...