Collerton D, Barnes J, Diederich NJ, Dudley R, Ffytche D, Friston K, Goetz CG, Goldman JG, Jardri R, Kulisevsky J, Lewis SJG, Nara S, O'Callaghan C, Onofrj M, Pagonabarraga J, Parr T, Shine JM, Stebbins G, Taylor JP, Tsuda I, and Weil RS
Despite decades of research, we do not definitively know how people sometimes see things that are not there. Eight models of complex visual hallucinations have been published since 2000, including Deafferentation, Reality Monitoring, Perception and Attention Deficit, Activation, Input, and Modulation, Hodological, Attentional Networks, Active Inference, and Thalamocortical Dysrhythmia Default Mode Network Decoupling. Each was derived from different understandings of brain organisation. To reduce this variability, representatives from each research group agreed an integrated Visual Hallucination Framework that is consistent with current theories of veridical and hallucinatory vision. The Framework delineates cognitive systems relevant to hallucinations. It allows a systematic, consistent, investigation of relationships between the phenomenology of visual hallucinations and changes in underpinning cognitive structures. The episodic nature of hallucinations highlights separate factors associated with the onset, persistence, and end of specific hallucinations suggesting a complex relationship between state and trait markers of hallucination risk. In addition to a harmonised interpretation of existing evidence, the Framework highlights new avenues of research, and potentially, new approaches to treating distressing hallucinations., Competing Interests: Conflicts of interest The following authors report no competing interests: James Barnes, Robert Dudley, Nico Diederich, Dominic ffytche, Karl Friston, Simon Lewis, Shigetoshi Nara, Claire O’Callaghan, Javier Pagonabarraga, James M Shine, Ichiro Tsuda. Daniel Collerton has received royalty payments from Wiley publishers. Christopher C Goetz has received faculty stipends from the International Parkinson and Movement Disorder Society, Guest professorship honoraria provided by University of Chicago and Illinois State Neurological Society, and a stipend as Volume Editor from Elsevier Publishers. He has also received royalty payments from Elsevier Publishers and Wolters Kluwer Publishers. Jennifer G Goldman has received grant/research support from Acadia Pharmaceuticals and honoraria from Medscape. Renaud Jardri has been invited to scientific meetings and expert boards by Lundbeck, Janssen and Otsuka. Jaime Kulisevsky has received fees for presentations or advisory boards from: Teva, UCB, Roche, Abbvie, Zambon, Bial, Sanofii and Neuroderm. Marco Onofrj has served on the scientific advisory boards of GlaxoSmithKline, Novartis, Lundbeck, Eisai, Valeant, Medtronic, and Newron; has received speaker honoraria from Zambon, the World Parkinson Congress, the Movement Disorder Society, and the Atypical Dementias congress; publishing royalties from Springer; was an invited guest and lecturer for the Mental Disorders in Parkinson Disease Congress; serves on the editorial board of Medicine (Baltimore) and Frontiers in Neuroscience; has been employed as a speaker for Boehringer Ingelheim, GlaxoSmithKline, UCB, and Zambon; and has received research support from the Italian Ministry of Health and the Italian Ministry of Education. Glenn Stebbins received compensation for consulting and advisory board membership from Acadia Pharmaceuticals, Adamas Pharmaceuticals, Biogen, Ceregene, CHDI Management, Neurocrine Biosciences, Pfizer, Tools-4-Patients, Ultragenyx and the Sunshine Care Foundation. John-Paul Taylor has received speaker fees from GE Healthcare. He has consulted for Kirin Kyowa and Sosei-Heptares. Rimona S Weil has received speaking honoraria from GE Healthcare and writing honoraria from Britannia., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)