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Inferior temporal cortex leads prefrontal cortex in response to a violation of a learned sequence

CEREBRAL CORTEX 2023年第6期33卷 3124-3141页

作者： Esmailpour, Hamideh Raman, Rajani Vogels, Rufin Katholieke Univ Leuven Dept Neurosci Lab Neuro En Psychofysiol Herestr 49 B-3000 Leuven Belgium Katholieke Univ Leuven Leuven Brain Inst ON V Herestr 49 B-3000 Leuven Belgium

Primates learn statistical regularities that are embedded in visual sequences, a form of statistical learning. Single-unit recordings in macaques showed that inferior temporal (IT) neurons are sensitive to statistical regularities in visual sequences. Here, we asked whether ventrolateral prefrontal cortex (VLPFC), which is connected to IT, is also sensitive to the transition probabilities in visual sequences and whether the statistical learning signal in IT originates in VLPFC. We recorded simultaneously multiunit activity (MUA) and local field potentials (LFPs) in IT and VLPFC after monkeys were exposed to triplets of images with a fixed presentation order. In both areas, the MUA was stronger to images that violated the learned sequence (deviants) compared to the same images presented in the learned triplets. The high-gamma and beta LFP power showed an enhanced and suppressed response, respectively, to the deviants in both areas. The enhanced response was present also for the image following the deviant, suggesting a sensitivity for temporal adjacent dependencies in IT and VLPFC. The increased response to the deviant occurred later in VLPFC than in IT, suggesting that the deviant response in IT was not inherited from VLPFC. These data support predictive coding theories that propose a feedforward flow of prediction errors.

关键词： statistical learning predictive coding inferior temporal cortex prefrontal cortex expectation suppression

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Psilocybin Induces Aberrant Prediction Error Processing of Tactile Mismatch Responses-A Simultaneous EEG-FMRI Study

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CEREBRAL CORTEX 2022年第1期32卷 186-196页

作者： Duerler, Patricia Brem, Silvia Fraga-Gonzalez, Gorka Neef, Tiffany Allen, Micah Zeidman, Peter Staempfli, Philipp Vollenweider, Franz X. Preller, Katrin H. Univ Hosp Psychiat Zurich Dept Psychiat Psychotherapy & Psychosomat Neuropsychopharmacol & Brain Imaging Lenggstr 31 CH-8032 Zurich Switzerland Univ Zurich Univ Hosp Psychiat Dept Child & Adolescent Psychiat & Psychotherapy CH-8032 Zurich Switzerland Aarhus Univ Aarhus Inst Adv Studies DK-8000 C Aarhus Denmark Aarhus Univ Hosp Ctr Funct Integrat Neurosci Dept Clin Med DK-8000 C Aarhus Denmark Univ Cambridge Cambridge Psychiat Cambridge CB2 8AH England UCL Wellcome Ctr Human Neuroimaging London WC1N 3AR England Univ Hosp Psychiat Zurich Dept Psychiat Psychotherapy & Psychosomat CH-8032 Zurich Switzerland

As source of sensory information, the body provides a sense of agency and self/non-self-discrimination. The integration of bodily states and sensory inputs with prior beliefs has been linked to the generation of bodily self-consciousness. The ability to detect surprising tactile stimuli is essential for the survival of an organism and for the formation of mental body representations. Despite the relevance for a variety of psychiatric disorders characterized by altered body and self-perception, the neurobiology of these processes is poorly understood. We therefore investigated the effect of psilocybin (Psi), known to induce alterations in self-experience, on tactile mismatch responses by combining pharmacological manipulations with simultaneous electroencephalography-functional magnetic resonance imaging (EEG-fMRI) recording. Psi reduced activity in response to tactile surprising stimuli in frontal regions, the visual cortex, and the cerebellum. Furthermore, Psi reduced tactile mismatch negativity EEG responses at frontal electrodes, associated with alterations of body- and self-experience. This study provides first evidence that Psi alters the integration of tactile sensory inputs through aberrant prediction error processing and highlights the importance of the 5-HT2A system in tactile deviancy processing as well as in the integration of bodily and self-related stimuli. These findings may have important implications for the treatment of psychiatric disorders characterized by aberrant bodily self-awareness.

关键词： 5-HT2A bodily self disembodiment predictive coding psilocybin tactile mismatch negativity

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Cortical ensembles selective for context

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PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2021年第14期118卷 2026179118-2026179118页

作者： Hamm, Jordan P. Shymkiv, Yuriy Han, Shuting Yang, Weijian Yuste, Rafael Columbia Univ Dept Biol Sci New York NY 10027 USA Univ Calif Davis Dept Elect & Comp Engn Davis CA 95616 USA

Neural processing of sensory information is strongly influenced by context. For instance, cortical responses are reduced to predictable stimuli, while responses are increased to novel stimuli that deviate from contextual regularities. Such bidirectional modulation based on preceding sensory context is likely a critical component or manifestation of attention, learning, and behavior, yet how it arises in cortical circuits remains unclear. Using volumetric two-photon calcium imaging and local field potentials in primary visual cortex (V1) from awake mice presented with visual "oddball" paradigms, we identify both reductions and augmentations of stimulus-evoked responses depending, on whether the stimulus was redundant or deviant, respectively. Interestingly, deviance-augmented responses were limited to a specific subset of neurons mostly in supragranular layers. These deviance-detecting cells were spatially intermixed with other visually responsive neurons and were functionally correlated, forming a neuronal ensemble. Optogenetic suppression of prefrontal inputs to V1 reduced the contextual selectivity of deviance-detecting ensembles, demonstrating a causal role for top-down inputs. The presence of specialized context-selective ensembles in primary sensory cortex, modulated by higher cortical areas, provides a circuit substrate for the brain's construction and selection of prediction errors, computations which are key for survival and deficient in many psychiatric disorders.

关键词： predictive coding circuits neocortex

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An information-theoretic perspective on the costs of cognition

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NEUROPSYCHOLOGIA 2019年第0期123卷 5-18页

作者： Zenon, Alexandre Solopchuk, Oleg Pezzulo, Giovanni Univ Bordeaux Inst Neurosci Cognit & Integrat Aquitaine Bordeaux France Catholic Univ Louvain Inst Neurosci Brussels Belgium CNR Inst Cognit Sci & Technol Via San Martino Battaglia 44 I-00185 Rome Italy

In statistics and machine learning, model accuracy is traded off with complexity, which can be viewed as the amount of information extracted from the data. Here, we discuss how cognitive costs can be expressed in terms of similar information costs, i.e. as a function of the amount of information required to update a person's prior knowledge (or internal model) to effectively solve a task. We then examine the theoretical consequences that ensue from this assumption. This framework naturally explains why some tasks - for example, unfamiliar or dual tasks - are costly and permits to quantify these costs using information-theoretic measures. Finally, we discuss brain implementation of this principle and show that subjective cognitive costs can originate either from local or global capacity limitations on information processing or from increased rate of metabolic alterations. These views shed light on the potential adaptive value of cost-avoidance mechanisms.

关键词： Cognitive effort Information theory Active inference predictive coding Efficient coding Computational neuroscience

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Late deviance detection in rats is reduced, while early deviance detection is augmented by the NMDA receptor antagonist MK-801

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SCHIZOPHRENIA RESEARCH 2018年 191卷 43-50页

作者： Harms, L. Fulham, W. R. Todd, J. Meehan, C. Schall, U. Hodgson, D. M. Michie, P. T. Univ Newcastle Sch Psychol Callaghan NSW Australia Prior Ctr Brain & Mental Hlth Res Callaghan NSW Australia Hunter Med Res Inst Newcastle NSW Australia Schizophrenia Res Inst Randwick NSW Australia Univ Newcastle Sch Med & Publ Hlth Callaghan NSW Australia

One of the most robust electrophysiological features of schizophrenia is reduced mismatch negativity, a component of the event related potential (ERP) induced by rare and unexpected stimuli in an otherwise regular pattern. Emerging evidence suggests that mismatch negativity (MMN) is not the only ERP index of deviance detection in the mammalian brain and that sensitivity to deviant sounds in a regular background can be observed at earlier latencies in both the human and rodent brain. Pharmacological studies in humans and rodents have previously found that MMN reductions similar to those seen in schizophrenia can be elicited by N-methyl-D-aspartate (NMDA) receptor antagonism, an observation in agreement with the hypothesised role of NMDA receptor hypofunction in schizophrenia pathogenesis. However, it is not known how NMDA receptor antagonism affects early deviance detection responses. Here, we show that NMDA antagonism impacts both early and late deviance detection responses. By recording EEG in awake, freely-moving rats in a drug-free condition and after varying doses of NMDA receptor antagonist MK-801, we found the hypothesised reduction of deviance detection for a late, negative potential (N55). However, the amplitude of an early component, P13, as well as deviance detection evident in the same component, were increased by NMDA receptor antagonism. These findings indicate that late deviance detection in rats is similar to human MMN, but the surprising effect of MK-801 in increasing ERP amplitudes as well as deviance detection at earlier latencies suggests that future studies in humans should examine ERPs over early latencies in schizophrenia and after NMDA antagonism. (c) 2017 Elsevier B.V. All rights reserved.

关键词： Mismatch negativity (MMN) MK-801 N-methyl-D-aspartate (NMDA) receptor Rat Schizophrenia predictive coding

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Predictability of what or where reduces brain activity, but a bottleneck occurs when both are predictable

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NEUROIMAGE 2018年 167卷 224-236页

作者： Davis, Ben Hasson, Uri Univ Trento Ctr Mind Brain Sci CIMeC Rovereto TN Italy

Detecting regularities in the sensory environment licenses predictions that enable adaptive behaviour. However, it is unclear whether predictions about object category, location, or both dimensions are mediated by overlapping systems, and relatedly, whether constructing predictions about both category and location is associated with processing bottlenecks. To examine this issue, in an fMRI study, we presented participants with image-series in which non-deterministic transition probabilities enabled predictions about either the location of the next image, its semantic category, both dimensions, or neither (the latter forming a "no-regularity" random baseline condition). Speaking to a common system, all three predictable conditions resulted in reduced BOLD activity in four clusters: left rostral anterior cingulate cortex;bilateral putamen, caudate and thalamus;right precentral gyrus, and left visual cortex. Pointing to a processing bottleneck, in some regions, a significant interaction between the two factors was found whereby category-predictable series were associated with lower activity -but only when location regularity was absent. Finally, category regularity decreased activation in areas of the ventral visual stream and semantic areas of lateral temporal cortex, and location regularity decreased activation in a dorsal fronto-parietal cluster, long implicated in the endogenous control of spatial attention. Our findings confirm and expand a role for dACC/dmPFC and striatum in monitoring or responding to uncertainty in the environment and point to a limited capacity bottleneck when multiple predictions are concurrently licensed.

关键词： Uncertainty Prediction Statistical learning predictive coding Disorder Entropy

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A mathematical model of embodied consciousness

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JOURNAL OF THEORETICAL BIOLOGY 2017年 428卷 106-131页

作者： Rudrauf, David Bennequin, Daniel Granic, Isabela Landini, Gregory Friston, Karl Williford, Kenneth Univ Geneva CISA FAPSE Campus Biotech Geneva Switzerland Univ Paris 07 Dept Math Paris France Radboud Univ Nijmegen Dept Behav Sci Nijmegen Netherlands Univ Iowa Dept Philosophy Iowa City IA USA UCL Welkome Trust Ctr Neuroimaging London England Univ Texas Arlington Dept Philosophy Arlington TX 76019 USA

We introduce a mathematical model of embodied consciousness, the Projective Consciousness Model (PCM), which is based on the hypothesis that the spatial field of consciousness (FoC) is structured by a projective geometry and under the control of a process of active inference. The FoC in the PCM combines multisensory evidence with prior beliefs in memory and frames them by selecting points of view and perspectives according to preferences. The choice of projective frames governs how expectations are transformed by consciousness. Violations of expectation are encoded as free energy. Free energy minimization drives perspective taking, and controls the switch between perception, imagination and action. In the PCM, consciousness functions as an algorithm for the maximization of resilience, using projective perspective taking and imagination in order to escape local minima of free energy. The PCM can account for a variety of psychological phenomena: the characteristic spatial phenomenology of subjective experience, the distinctions and integral relationships between perception, imagination and action, the role of affective processes in intentionality, but also perceptual phenomena such as the dynamics of bistable figures and body swap illusions in virtual reality. It relates phenomenology to function, showing the computational advantages of consciousness. It suggests that changes of brain states from unconscious to conscious reflect the action of projective transformations and suggests specific neurophenomenological hypotheses about the brain, guidelines for designing artificial systems, and formal principles for psychology. (C) 2017 Elsevier Ltd. All rights reserved.

关键词： Consciousness Mathematical model Projective geometry Active inference Embodiment Self-Consciousness Perspective taking Free energy minimization Point of view predictive coding Bayesian approaches to cognition Cognitive resilience Spatial phenomenology Subjective experience

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PICTURE coding FOR VIDEOTELEPHONY, TELEVISION AND HIGH-DEFINITION TELEVISION

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ANNALES DES TELECOMMUNICATIONS-ANNALS OF TELECOMMUNICATIONS 1990年第9-10期45卷 519-527页

作者： DELOGNE, P 1. Laboratoire de télécommunications et d’hyperfréquences batiment Maxwell Université catholique de Louvain B-1348 Louvain-la-Neuve Belgium

After a brief introduction explaining the present-day context of picture coding and bitrate reduction techniques for videotelephony, television and high-definition television, the basic principles of bitrate reduction techniques are reviewed. These techniques include spatiotemporal resolution limitation, decorrelative processes and noise weighting. Each of these topics is reviewed and a typical coding algorithm is presented. Adequate entropic codes are discussed. The paper, which is of a tutorial nature, ends with a brief discussion of the impact of future network techniques and of their influence on further research.

关键词： Image coding Videophone Television Passband compression predictive coding Orthogonal transformation Entropy Didactic paper Codage image Visiophone Télévision Compression bande passante Codage prédictif Transformation orthogonale Entropie Exposé didactique

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EXPERIMENTAL BRAIN RESEARCH 2018年第5期236卷 1519-1530页

作者： Rosburg, Timm Weigl, Michael Thiel, Ronja Mager, Ralph Univ Basel Univ Psychiat Clin Dept Forens Psychiat Wilhelm Klein Str 27 CH-4002 Basel Switzerland Saarland Univ Dept Psychol Expt Neuropsychol Unit Campus A2-4 D-66123 Saarbrucken Germany

Mismatch negativity (MMN) represents an event-related potential (ERP) component which is elicited by deviant sound events in an otherwise regular, repetitive stimulation. The MMN amplitude typically decreases when two identical deviants are presented in direct succession, but it remains stable when the two deviants vary from the standard in different features. Less is known about such repetition effects on another ERP component, the P3a, which usually follows the MMN. In the current study, we investigated how the P3a was affected by identical and non-identical repetitions of sound deviants. The ERP analysis revealed that the P3a amplitudes were strongly diminished when the repeated deviants were identical, but the P3a remained stable when the repeated deviants varied. The findings suggest that not only the deviance detection system, as reflected in the MMN, but also subsequent attention switch systems, as reflected in the P3a, operate independently across different sound features.

关键词： Attention Event-related potentials Mismatch negativity Prefrontal cortex predictive coding

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Onboard Image Processing System for Hyperspectral Sensor

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SENSORS 2015年第10期15卷 24926-24944页

作者： Hihara, Hiroki Moritani, Kotaro Inoue, Masao Hoshi, Yoshihiro Iwasaki, Akira Takada, Jun Inada, Hitomi Suzuki, Makoto Seki, Taeko Ichikawa, Satoshi Tanii, Jun NEC Space Technol Ltd Fuchu Tokyo 1838551 Japan Univ Tokyo Res Ctr Adv Sci & Technol Meguro Ku Tokyo 1538904 Japan NEC Corp Ltd Cent Res Lab Nakahara Ku Kawasaki Kanagawa 2118666 Japan NEC Corp Ltd Div Space Syst Fuchu Tokyo 1838551 Japan Japan Aerosp Explorat Agcy JAXA Inst Space Astronaut Sci Chuo Ku Sagamihara Kanagawa 2525210 Japan Japan Aerosp Explorat Agcy JAXA Aerosp Res & Dev Directorate Tsukuba Ibaraki 3058505 Japan Japan Space Syst Minato Ku Tokyo 1050011 Japan

Onboard image processing systems for a hyperspectral sensor have been developed in order to maximize image data transmission efficiency for large volume and high speed data downlink capacity. Since more than 100 channels are required for hyperspectral sensors on Earth observation satellites, fast and small-footprint lossless image compression capability is essential for reducing the size and weight of a sensor system. A fast lossless image compression algorithm has been developed, and is implemented in the onboard correction circuitry of sensitivity and linearity of Complementary Metal Oxide Semiconductor (CMOS) sensors in order to maximize the compression ratio. The employed image compression method is based on Fast, Efficient, Lossless Image compression System (FELICS), which is a hierarchical predictive coding method with resolution scaling. To improve FELICS's performance of image decorrelation and entropy coding, we apply a two-dimensional interpolation prediction and adaptive Golomb-Rice coding. It supports progressive decompression using resolution scaling while still maintaining superior performance measured as speed and complexity. coding efficiency and compression speed enlarge the effective capacity of signal transmission channels, which lead to reducing onboard hardware by multiplexing sensor signals into a reduced number of compression circuits. The circuitry is embedded into the data formatter of the sensor system without adding size, weight, power consumption, and fabrication cost.

关键词： hyperspectral sensor Golomb-Rice coding hierarchical prediction lossless image compression predictive coding resolution scaling onboard correction smile correction

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