scholarly journals Adjudicating Between Local and Global Architectures of Predictive Processing in the Subcortical Auditory Pathway

2021 ◽  
Vol 15 ◽  
Author(s):  
Alejandro Tabas ◽  
Katharina von Kriegstein

Predictive processing, a leading theoretical framework for sensory processing, suggests that the brain constantly generates predictions on the sensory world and that perception emerges from the comparison between these predictions and the actual sensory input. This requires two distinct neural elements: generative units, which encode the model of the sensory world; and prediction error units, which compare these predictions against the sensory input. Although predictive processing is generally portrayed as a theory of cerebral cortex function, animal and human studies over the last decade have robustly shown the ubiquitous presence of prediction error responses in several nuclei of the auditory, somatosensory, and visual subcortical pathways. In the auditory modality, prediction error is typically elicited using so-called oddball paradigms, where sequences of repeated pure tones with the same pitch are at unpredictable intervals substituted by a tone of deviant frequency. Repeated sounds become predictable promptly and elicit decreasing prediction error; deviant tones break these predictions and elicit large prediction errors. The simplicity of the rules inducing predictability make oddball paradigms agnostic about the origin of the predictions. Here, we introduce two possible models of the organizational topology of the predictive processing auditory network: (1) the global view, that assumes that predictions on the sensory input are generated at high-order levels of the cerebral cortex and transmitted in a cascade of generative models to the subcortical sensory pathways; and (2) the local view, that assumes that independent local models, computed using local information, are used to perform predictions at each processing stage. In the global view information encoding is optimized globally but biases sensory representations along the entire brain according to the subjective views of the observer. The local view results in a diminished coding efficiency, but guarantees in return a robust encoding of the features of sensory input at each processing stage. Although most experimental results to-date are ambiguous in this respect, recent evidence favors the global model.

Author(s):  
A. Greenhouse-Tucknott ◽  
J. B. Butterworth ◽  
J. G. Wrightson ◽  
N. J. Smeeton ◽  
H. D. Critchley ◽  
...  

AbstractFatigue is a common experience in both health and disease. Yet, pathological (i.e., prolonged or chronic) and transient (i.e., exertional) fatigue symptoms are traditionally considered distinct, compounding a separation between interested research fields within the study of fatigue. Within the clinical neurosciences, nascent frameworks position pathological fatigue as a product of inference derived through hierarchical predictive processing. The metacognitive theory of dyshomeostasis (Stephan et al., 2016) states that pathological fatigue emerges from the metacognitive mechanism in which the detection of persistent mismatches between prior interoceptive predictions and ascending sensory evidence (i.e., prediction error) signals low evidence for internal generative models, which undermine an agent’s feeling of mastery over the body and is thus experienced phenomenologically as fatigue. Although acute, transient subjective symptoms of exertional fatigue have also been associated with increasing interoceptive prediction error, the dynamic computations that underlie its development have not been clearly defined. Here, drawing on the metacognitive theory of dyshomeostasis, we extend this account to offer an explicit description of the development of fatigue during extended periods of (physical) exertion. Accordingly, it is proposed that a loss of certainty or confidence in control predictions in response to persistent detection of prediction error features as a common foundation for the conscious experience of both pathological and nonpathological fatigue.


2019 ◽  
Author(s):  
Catalina Valdés-Baizabal ◽  
Guillermo V. Carbajal ◽  
David Pérez-González ◽  
Manuel S. Malmierca

AbstractThe predictive processing framework describes perception as a hierarchical predictive model of sensation. Higher-level neural structures constrain the processing at lower-level structures by suppressing synaptic activity induced by predictable sensory input. But when predictions fail, deviant input is forwarded bottom-up as ‘prediction error’ to update the perceptual model. The earliest prediction error signals identified in the auditory pathway emerge from the nonlemniscal inferior colliculus (IC). The drive that these feedback signals exert on the perceptual model depends on their ‘expected precision’, which determines the postsynaptic gain applied in prediction error forwarding. Expected precision is theoretically encoded by the neuromodulatory (e.g., dopaminergic) systems. To test this empirically, we recorded extracellular responses from the rat nonlemniscal IC to oddball and cascade sequences before, during and after the microiontophoretic application of dopamine or eticlopride (a D2-like receptor antagonist). Hence, we studied dopaminergic modulation on the subcortical processing of unpredictable and predictable auditory changes. Results demonstrate that dopamine reduces the net neuronal responsiveness exclusively to unexpected input, without significantly altering the processing of expected auditory events at population level. We propose that, in natural conditions, dopaminergic projections from the thalamic subparafascicular nucleus to the nonlemniscal IC could serve as a precision-weighting mechanism mediated by D2-like receptors. Thereby, the levels of dopamine release in the nonlemniscal IC could modulate the early bottom-up flow of prediction error signals in the auditory system by encoding their expected precision.


2018 ◽  
Author(s):  
Beren Millidge ◽  
Richard Shillcock

We propose a novel predictive processing account of bottom-up visual saliency in which salience is simply the low-level prediction error between the sense-data and the predictions produced by the generative models in the brain. We test this with modelling in which we use cross-predicting deep autoencoders to create salience maps in an entirely unsupervised way. The resulting maps closely mimic experimentally derived human saliency maps and also spontaneously learn a centre bias, a robust viewing behaviour seen in human participants.


2018 ◽  
Author(s):  
D.R. Quiroga-Martinez ◽  
N.C. Hansen ◽  
A. Højlund ◽  
M. Pearce ◽  
E. Brattico ◽  
...  

AbstractTheories of predictive processing propose that prediction error responses are modulated by the certainty of the predictive model or precision. While there is some evidence for this phenomenon in the visual and, to a lesser extent, the auditory modality, little is known about whether it operates in the complex auditory contexts of daily life. Here, we examined how prediction error responses behave in a more complex and ecologically valid auditory context than those typically studied. We created musical tone sequences with different degrees of pitch uncertainty to manipulate the precision of participants’ auditory expectations. Magnetoencephalography was used to measure the magnetic counterpart of the mismatch negativity (MMNm) as a neural marker of prediction error in a multi-feature paradigm. Pitch, slide, intensity and timbre deviants were included. We compared high-entropy stimuli, consisting of a set of non-repetitive melodies, with low-entropy stimuli consisting of a simple, repetitive pitch pattern. Pitch entropy was quantitatively assessed with an information-theoretic model of auditory expectation. We found a reduction in pitch and slide MMNm amplitudes in the high-entropy as compared to the low-entropy context. No significant differences were found for intensity and timbre MMNm amplitudes. Furthermore, in a separate behavioral experiment investigating the detection of pitch deviants, similar decreases were found for accuracy measures in response to more fine-grained increases in pitch entropy. Our results are consistent with a precision modulation of auditory prediction error in a musical context, and suggest that this effect is specific to features that depend on the manipulated dimension—pitch information, in this case.HighlightsThe mismatch negativity (MMNm) is reduced in musical contexts with high pitch uncertaintyThe MMNm reduction is restricted to pitch-related featuresAccuracy during deviance detection is reduced in contexts with higher uncertaintyThe results suggest a feature-selective precision modulation of prediction errorMaterials, data and scripts can be found in the Open Science Framework repository: http://bit.ly/music_entropy_MMNDOI: 10.17605/OSF.IO/MY6TE


Author(s):  
Lauren Swiney

Over the last thirty years the comparator hypothesis has emerged as a prominent account of inner speech pathology. This chapter discusses a number of cognitive accounts broadly derived from this approach, highlighting the existence of two importantly distinct notions of inner speech in the literature; one as a prediction in the absence of sensory input, the other as an act with sensory consequences that are themselves predicted. Under earlier frameworks in which inner speech is described in the context of classic models of motor control, I argue that these two notions may be compatible, providing two routes to inner speech pathology. Under more recent accounts grounded in the architecture of Bayesian predictive processing, I argue that “active inference” approaches to action generation pose serious challenges to the plausibility of the latter notion of inner speech, while providing the former notion with rich explanatory possibilities for inner speech pathology.


1999 ◽  
Vol 174 (S37) ◽  
pp. 2-6 ◽  
Author(s):  
A. Carlsson ◽  
L. O. Hansson ◽  
N. Waters ◽  
M. L. Carlsson

Although the presence of hyperdopaminergia has been demonstrated in the brains of people with schizophrenia, at least in some circumstances, other neurotransmitters are important in this disorder, and a glutamatergic deficiency model of schizophrenia is proposed. It is suggested that the amount of sensory input allowed to reach the cerebral cortex is restricted by an inhibitory effect of the striatal complexes on the thalamus, thereby protecting it from being overwhelmed. Several strands of evidence are presented to support the concept that a weakened glutamatergic tone increases the risk of sensory overload and of exaggerated responses in the monoaminergic systems that could result in psychosis.


Author(s):  
Michiel Van Elk ◽  
Harold Bekkering

We characterize theories of conceptual representation as embodied, disembodied, or hybrid according to their stance on a number of different dimensions: the nature of concepts, the relation between language and concepts, the function of concepts, the acquisition of concepts, the representation of concepts, and the role of context. We propose to extend an embodied view of concepts, by taking into account the importance of multimodal associations and predictive processing. We argue that concepts are dynamically acquired and updated, based on recurrent processing of prediction error signals in a hierarchically structured network. Concepts are thus used as prior models to generate multimodal expectations, thereby reducing surprise and enabling greater precision in the perception of exemplars. This view places embodied theories of concepts in a novel predictive processing framework, by highlighting the importance of concepts for prediction, learning and shaping categories on the basis of prediction errors.


2021 ◽  
Vol 12 ◽  
Author(s):  
Joerg Fingerhut

This paper argues that the still-emerging paradigm of situated cognition requires a more systematic perspective on media to capture the enculturation of the human mind. By virtue of being media, cultural artifacts present central experiential models of the world for our embodied minds to latch onto. The paper identifies references to external media within embodied, extended, enactive, and predictive approaches to cognition, which remain underdeveloped in terms of the profound impact that media have on our mind. To grasp this impact, I propose an enactive account of media that is based on expansive habits as media-structured, embodied ways of bringing forth meaning and new domains of values. We apply such habits, for instance, when seeing a picture or perceiving a movie. They become established through a process of reciprocal adaptation between media artifacts and organisms and define the range of viable actions within such a media ecology. Within an artifactual habit, we then become attuned to a specific media work (e.g., a TV series, a picture, a text, or even a city) that engages us. Both the plurality of habits and the dynamical adjustments within a habit require a more flexible neural architecture than is addressed by classical cognitive neuroscience. To detail how neural and media processes interlock, I will introduce the concept of neuromediality and discuss radical predictive processing accounts that could contribute to the externalization of the mind by treating media themselves as generative models of the world. After a short primer on general media theory, I discuss media examples in three domains: pictures and moving images; digital media; architecture and the built environment. This discussion demonstrates the need for a new cognitive media theory based on enactive artifactual habits—one that will help us gain perspective on the continuous re-mediation of our mind.


2021 ◽  
Vol 15 ◽  
Author(s):  
Fabian Kiepe ◽  
Nils Kraus ◽  
Guido Hesselmann

Self-generated auditory input is perceived less loudly than the same sounds generated externally. The existence of this phenomenon, called Sensory Attenuation (SA), has been studied for decades and is often explained by motor-based forward models. Recent developments in the research of SA, however, challenge these models. We review the current state of knowledge regarding theoretical implications about the significance of Sensory Attenuation and its role in human behavior and functioning. Focusing on behavioral and electrophysiological results in the auditory domain, we provide an overview of the characteristics and limitations of existing SA paradigms and highlight the problem of isolating SA from other predictive mechanisms. Finally, we explore different hypotheses attempting to explain heterogeneous empirical findings, and the impact of the Predictive Coding Framework in this research area.


2019 ◽  
pp. 191-205 ◽  
Author(s):  
Jakob Hohwy

Andy Clark’s exciting work on predictive processing provides the umbrella under which his hugely influential previous work on embodied and extended cognition seeks a unified home. This chapter argues that in fact predictive processing harbours internalist, inferentialist and epistemic tenets that cannot leave embodied and extended cognition unchanged. Predictive processing cannot do the work Clark requires of it without relying on rich, preconstructive internal representations of the world, nor without engaging in paradigmatically rational integration of prior knowledge and new sensory input. Hence, next to Clark’s image of fluid “uncertainty surfing” is an equally valid image of more emaciated and plodding world-modelling. Rather than underpinning orthodox embodied and extended approches, predictive processing therefore presents an opportunity for a potentially fruitful new synthesis of cognitivist and embodied approaches to cognition.


Sign in / Sign up

Export Citation Format

Share Document