Under the predictive coding hypothesis, specific spatiotemporal patterns of cortical activation are postulated to occur during sensory processing as expectations generate feedback predictions and prediction errors gen...
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Under the predictive coding hypothesis, specific spatiotemporal patterns of cortical activation are postulated to occur during sensory processing as expectations generate feedback predictions and prediction errors generate feedforward signals. Establishing experimental evidence for this information flow within cortical hierarchy has been difficult, especially in humans, due to spatial and temporal limitations of non-invasive measures of cortical activity. This study investigated cortical responses to auditory novelty using the local/global deviant paradigm, which engages the hierarchical network underlying auditory predictive coding over short ('local deviance';LD) and long ('global deviance';GD) time scales. Electrocorticographic responses to auditory stimuli were obtained in neurosurgical patients from regions of interest (ROIs) including auditory, auditory-related and prefrontal cortex. LD and GD effects were assayed in averaged evoked potential (AEP) and high gamma (70-150 Hz) signals, the former likely dominated by local synaptic currents and the latter largely reflecting local spiking activity. AEP LD effects were distributed across all ROIs, with greatest percentage of significant sites in core and non-core auditory cortex. High gamma LD effects were localized primarily to auditory cortex in the superior temporal plane and on the lateral surface of the superior temporal gyrus (STG). LD effects exhibited progressively longer latencies in core, non-core, auditory-related and prefrontal cortices, consistent with feedforward signaling. The spatial distribution of AEP GD effects overlapped that of LD effects, but high gamma GD effects were more restricted to non-core areas. High gamma GD effects had shortest latencies in STG and preceded AEP GD effects in most ROIs. This latency profile, along with the paucity of high gamma GD effects in the superior temporal plane, suggest that the STG plays a prominent role in initiating novelty detection signals over long time
Time, or more specifically temporal structure, is a critical variable in understanding how the auditory system uses acoustic patterns to predict input, and to filter events based on their relevance. A key index of thi...
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Time, or more specifically temporal structure, is a critical variable in understanding how the auditory system uses acoustic patterns to predict input, and to filter events based on their relevance. A key index of this filtering process is the auditory evoked potential component known as mismatch negativity or MMN. In this paper we review findings of smaller MMN in schizophrenia through the lens of time as an influential contextual variable. More specifically, we review studies that show how MMN to a locally rare pattern-deviation is modulated by the longer-term context in which it occurs. Empirical data is presented from a non-clinical sample confirming that the absence of a stable higher-order structure to sound sequences alters the way MMN amplitude changes over time. This result is discussed in relation to how hierarchical pattern learning might enrich our understanding of how and why MMN amplitude modulation is disrupted in schizophrenia. (c) 2017 Elsevier B.V. All rights reserved.
Non-dual meditation aims to undo maladaptive cognitive and affective patterns by recognizing their constructed and transient nature. We previously found high-amplitude spontaneous gamma (25-40 Hz) oscillatory activity...
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Non-dual meditation aims to undo maladaptive cognitive and affective patterns by recognizing their constructed and transient nature. We previously found high-amplitude spontaneous gamma (25-40 Hz) oscillatory activity during such practice. Nonetheless, it is unclear how this meditation state differs from other practices, in terms of perceptual information processing. Here, we hypothesized that non-dual meditation can downregulate the automatic formation of perceptual habits. To investigate this hypothesis, we recorded EEG from expert Buddhist meditation practitioners and matched novices to measure two components of the auditory evoked response: the Mismatch Negativity (MMN) and the Late Frontal Negativity (LFN), a potential observed at a latency sensitive to attentional engagement to the auditory environment, during the practices of Open Presence (OP) and Focused Attention (FA), as well as during a control state, in the context of a passive oddball paradigm. We found an increase in gamma oscillatory power during both meditation states in expert practitioners and an interaction between states and groups in the amplitude of the MMN. A further investigation identified the specific interplay between the MMN and the LFN as a possible marker to differentiate the two meditation states as a function of expertise. In experts, the MMN increased during FA, compared to OP, while the opposite pattern was observed at the LFN latency. We propose that the state of OP in experts is characterized by increased sensory monitoring and reduced perceptual inferences compared to FA. This study represents a first attempt to describe the impact of non-dual meditation states on the regulation of automatic brain predictive processes.
The so-called "dark room problem" makes vivd the challenges that purely predictive models face in accounting for motivation. I argue that the problem is a serious one. Proposals for solving the dark room pro...
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The so-called "dark room problem" makes vivd the challenges that purely predictive models face in accounting for motivation. I argue that the problem is a serious one. Proposals for solving the dark room problem via predictive coding architectures are either empirically inadequate or computationally intractable. The Free Energy principle might avoid the problem, but only at the cost of setting itself up as a highly idealized model, which is then literally false to the world. I draw at least one optimistic conclusion, however. Real-world, real-time systems may embody motivational states in a variety of ways consistent with idealized principles like FEP, including ways that are intuitively embodied and extended. This may allow predictive coding theorists to reconcile their account with embodied principles, even if it ultimately undermines loftier ambitions.
作者:
Vuust, PeterAarhus Univ
Royal Acad Mus Aarhus Aalborg Ctr Mus Brain Dept Clin Med Norrebrogade 44 Aarhus Denmark
A unique feature of music is its potential to make us want to move our feet and bodies to the rhythm of the musical beat. Even though the ability to synchronize our movements to music feels as a completely natural mus...
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ISBN:
(纸本)9783030016920;9783030016913
A unique feature of music is its potential to make us want to move our feet and bodies to the rhythm of the musical beat. Even though the ability to synchronize our movements to music feels as a completely natural music-related behavior to most humans (but see [1, 2] for rare cases of so-called beat-deafness in humans) this ability is rarely observed in animals [3], and usually depends on specific training regimes [4]. Our brains structure the musical beat into strong and weak beats even without any such information present in the auditory stimulus [5]. Furthermore, the tendency to move to a regular beat, with isochronous intervals, may persist even if the music that we listen to emphasizes musical events that lies between these beats as for syncopated rhythms [6] or in the case of polyrhythm [7, 8]. This indicates a cognitive discrepancy between what is heard - the rhythm - and the brain's internal structuring of the beat which in musicology is termed the meter. In the present paper, I shall argue that this discrepancy: (1) is related to prediction as a fundamental principle of brain processing, (2) gives rise to prediction error between lower - possibly sensory - and higher levels - possibly motor networks - in the hierarchical organized brain, and that (3) perception, learning and our inclination to move to the beat depends on the right balance between predictability and surprise. This predictive coding understanding of the brain mechanisms involved in movement related musical behavior may help us understand brain processes related to aesthetic experiences in general and in designing strategies for clinical intervention for patients with movement disorders.
作者:
Strauss, MelanieDehaene, StanislasUniv Paris Saclay
Univ Paris Sud Cognit Neuroimaging Unit NeuroSpin CtrINSERMCEA DSV I2BM Gif Sur Yvette France Univ Paris 05
Hotel Dieu Paris AP HP Sorbonne Paris CiteCtr Sommeil & VigilanceEA VI Paris France Univ Libre Bruxelles
Neuropsychol & Funct Imaging Res Grp Ctr Res Cognit & Neurosci Brussels Belgium Coll France
Paris France Univ Libre Bruxelles
Neuropsychol & Funct Imaging Res Grp UR2NF CRCN 50 Ave FD RooseveltCP191 B-1050 Brussels Belgium
Can the sleeping brain develop predictions of future auditory stimuli? Past research demonstrated disrupted prediction capabilities during sleep in the context of novel, arbitrary auditory sequences, but the availabil...
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Can the sleeping brain develop predictions of future auditory stimuli? Past research demonstrated disrupted prediction capabilities during sleep in the context of novel, arbitrary auditory sequences, but the availability of overlearned knowledge already stored in long-term memory could still be preserved. We tested the sleeping brain capabilities to detect violations of simple arithmetic facts. Sleeping participants were presented with spoken arithmetic facts such as two plus two is nine and brain responses to correct or incorrect results were recorded in electro and magneto-encephalography. Sleep responses were compared to both attentive and inattentive wakefulness. During attentive wakefulness, arithmetic violations elicited a succession of N400 and P600 effects, whereas no such activations could be recorded in sleep or in inattentive wakefulness. Still, small but significant effects remained in sleep, advocating for a preserved but partial accessibility to arithmetic facts stored in long-term memory and preserved predictions of low-level and already learned knowledge. Those effects were very different from residual activities seen in inattention, highlighting the differences of information processing between the sleeping and the inattentive brain.
We review a series of studies exploring distractor suppression. It is often assumed that preparatory distractor suppression is controlled via top-down mechanisms of attention akin to those that prepare brain areas for...
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We review a series of studies exploring distractor suppression. It is often assumed that preparatory distractor suppression is controlled via top-down mechanisms of attention akin to those that prepare brain areas for target enhancement. Here, we consider two alternative mechanisms: secondary inhibition and expectation suppression within a predictive coding framework. We draw on behavioural studies, evidence from neuroimaging and some animal studies. We conclude that there is very limited evidence for selective top-down control of preparatory inhibition. By contrast, we argue that distractor suppression often relies secondary inhibition of non-target items (relatively non-selective inhibition) and on statistical regularities of the environment, learned through direct experience.
Autism is a developmental condition, characterized by difficulties of social interaction and communication, as well as restricted interests and repetitive behaviors. Although several important conceptions have shed li...
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Autism is a developmental condition, characterized by difficulties of social interaction and communication, as well as restricted interests and repetitive behaviors. Although several important conceptions have shed light on specific facets, there is still no consensus about a universal yet specific theory in terms of its underlying mechanisms. While some theories have exclusively focused on sensory aspects, others have emphasized social difficulties. However, sensory and social processes in autism might be interconnected to a higher degree than what has been traditionally thought. We propose that a mismatch in sensory abilities across individuals can lead to difficulties on a social, i.e. interpersonal level and vice versa. In this article, we, therefore, selectively review evidence indicating an interrelationship between perceptual and social difficulties in autism. Additionally, we link this body of research with studies, which investigate the mechanisms of action control in social contexts. By doing so, we highlight that autistic traits are also crucially related to differences in integration, anticipation and automatic responding to social cues, rather than a mere inability to register and learn from social cues. Importantly, such differences may only manifest themselves in sufficiently complex situations, such as real-life social interactions, where such processes are inextricably linked. (C) 2017 The Authors. Published by Elsevier Ltd.
Sensory events produced by ourselves are known to lead to lower neural and perceptual impact than sensory events from other environmental sources. This sensory attenuation is widely assumed to result from control proc...
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Sensory events produced by ourselves are known to lead to lower neural and perceptual impact than sensory events from other environmental sources. This sensory attenuation is widely assumed to result from control processes that are specific to our own motor actions, potentially helping us to distinguish effects produced by ourselves and others. However, previous research cannot rule out that the putative self-attenuation in fact reflect actor-independent, general predictive mechanisms, which, in direct comparison, just highlight external events due to lower predictability of their onset and thus higher surprise. By measuring the auditory-evoked N1 component, we show that self-generation of sounds only lead to cortical attenuation when the onset of other-generated sounds is less predictable due to the absence of any predictive cues. The presence of a cue predicting the onset of auditory stimuli, in contrast, led to a reversal of the attenuation effect, with lower N1 amplitudes for other-generated sounds in contrast to self-generated sounds. Thus, contrary to prevalent assumptions sensory attenuation is not bound to self-generation per se. Rather, it appears to be the result of general mechanisms that does not reliably and selectively attenuate self-induced stimulation but is determined by a flexible processing of sensory input based on its predictability, contextual relevance and attentional salience.
The thalamus has long been suspected to have an important role in cognition, yet recent theories have favored a more corticocentric view. According to this view, the thalamus is an excitatory feedforward relay to or b...
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The thalamus has long been suspected to have an important role in cognition, yet recent theories have favored a more corticocentric view. According to this view, the thalamus is an excitatory feedforward relay to or between cortical regions, and cognitively relevant computations are exclusively cortical. Here, we review anatomical, physiological, and behavioral studies along evolutionary and theoretical dimensions, arguing for essential and unique thalamic computations in cognition. Considering their architectural features as well as their ability to initiate, sustain, and switch cortical activity, thalamic circuits appear uniquely suited for computing contextual signals that rapidly reconfigure task-relevant cortical representations. We introduce a framework that formalizes this notion, show its consistency with several findings, and discuss its prediction of thalamic roles in perceptual inference and behavioral flexibility. Overall, our framework emphasizes an expanded view of the thalamus in cognitive computations and provides a roadmap to test several of its theoretical and experimental predictions.
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