An algorithmic information theory of consciousness

Authors: G. Ruffini Providing objective metrics of conscious state is of great interest across multiple research and clinical fields—from neurology to artificial intelligence. Here we approach this challenge by proposing plausible mechanisms for the phenomenon of structured experience. In earlier work, we argued that the experience we call reality is a mental construct derived from […]

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Repeated stimulation of the posterior parietal cortex in patients in minimally conscious state: A sham-controlled randomized clinical trial

Authors: Huang W; Wannez S; Fregni F; Hu X; Jing S; Martens G; He M; Di H; Laureys S; Thibaut A Patients in unresponsive wakefulness syndrome (UWS e recov- ery of eyes opening while no behavioral sign of consciousness [1]) and in minimally conscious state (MCS e recovery of reproducible purposeful behaviors [2]) have no access to conventional rehabili- tation program, apart from pharmacological or […]

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Controlled clinical trial of repeated prefrontal tDCS in patients with chronic minimally conscious state

Authors: Aurore Thibaut; Sarah Wannez; Anne-Francoise Donneau; Camille Chatelle; Olivia Gosseries; Marie-Aurélie Bruno; Steven Laureys Objectives: To assess the effects of repeated transcranial direct current stimulation (tDCS) sessions on the level of consciousness in chronic patients in minimally conscious state (MCS). Methods: In this randomized double-blind sham-controlled crossover study, we enrolled 16 patients in chronic MCS. For 5 consecutive days, each patient […]

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Models, networks and algorithmic complexity

Authors: Ruffini, G I aim to show that models, classification or generating functions, invariances and datasets are algorithmically equivalent concepts once properly defined, and provide some concrete examples of them. I then show that a) neural networks (NNs) of different kinds can be seen to implement models, b) that perturbations of inputs and nodes in NNs […]

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Transcranial Electric Stimulation for Precision Medicine: A Spatiomechanistic Framework

Authors: Yavari F; Nitsche M; Ekhtiari H During recent years, non-invasive brain stimulation, including transcranial electrical stimulation (tES) in general, and transcranial direct current stimulation (tDCS) in particular, have created new hopes for treatment of neurological and psychiatric diseases. Despite promising primary results in some brain disorders, a more widespread application of tES is hindered by the unsolved […]

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Measures of metabolism and complexity in the brain of patients with disorders of consciousness

Authors: Bodart O; Gosseries O; Wannez S; Thibaut A; Annen J; Boly M; Rossanova M; Casali A; Casarotto S; Tononi G; Massimini M; Laureys S Background Making an accurate diagnosis in patients with disorders of consciousness remains challenging. 18F-fluorodeoxyglucose (FDG)–PET has been validated as a diagnostic tool in this population, and allows identifying unresponsive patients with a capacity for consciousness. In parallel, the perturbational complexity index (PCI), a […]

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Tracking dynamic interactions between structural and functional connectivity: a TMS/EEG-dMRI study

Authors:Amico E; Bodart O; Rosanova M; Gosseries O; Heine L; Van Mierlo P; Martial C; Massimini M; Marianazzo D; Laureys S Transcranial magnetic stimulation (TMS) in combination with neuroimaging techniques allows to measure the effects of a direct perturbation of the brain. When coupled with high-density electroencephalography (TMS/hd-EEG), TMS pulses revealed electrophysiological signatures of different cortical modules in health and disease. However, the neural […]

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Neural correlates of consciousness: progress and problems

Authors: Koch C; Massimini M; Boly M; Tononi G There have been a number of advances in the search for the neural correlates of consciousness — the minimum neural mechanisms sufficient for any one specific conscious percept. In this Review, we describe recent findings showing that the anatomical neural correlates of consciousness are primarily localized to a posterior cortical […]

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Modulation of Total Sleep Time by Transcranial Direct Current Stimulation (tDCS)

Authors: Frase L; Piosczyk H; Zittel S; Jahn F; Selhausen P; Krone L; Feige B; Mainberger F; Maier J M; Kuhn M; Kloppel S; Normann C; Sterr A; Spiegelhalder K; Riemann D; Nitsche M; Nissen C Arousal and sleep are fundamental physiological processes, and their modulation is of high clinical significance. This study tested the hypothesis that total sleep time (TST) in humans can be modulated by the non-invasive brain stimulation technique transcranial […]

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Brain–computer interfaces for communication and rehabilitation

Authors: Chaudhary U; Birbaumer N; Ramos-Murguialday A Brain–computer interfaces (BCIs) use brain activity to control external devices, thereby enabling severely disabled patients to interact with the environment. A variety of invasive and noninvasive techniques for controlling BCIs have been explored, most notably EEG, and more recently, near-infrared spectroscopy. Assistive BCIs are designed to enable paralyzed patients to communicate […]

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