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Unattended processing of hierarchical pitch variations in spoken sentences

BRAIN AND LANGUAGE 2018年 183卷 21-31页

作者： Li, Xiaoqing Chen, Yiya Chinese Acad Sci Inst Psychol CAS Key Lab Behav Sci 16 Lincui Rd Beijing 100101 Peoples R China Leiden Univ Ctr Linguist LUCL Leiden Netherlands LIBC Leiden Netherlands

An auditory oddball paradigm was employed to examine the unattended processing of pitch variation which functions to signal hierarchically different levels of meaning contrasts. Four oddball conditions were constructed by varying the pitch contour of critical words embedded in a Mandarin Chinese sentence. Two conditions included lexical-level word meaning contrasts (i.e. TONE condition) and the other two sentence-level information-status contrasts (i.e. ACCENTUATION condition). Both included stimuli with early vs. late acoustic cue divergence points. Results showed that the two early-cue conditions elicited earlier Mismatch Negativities, regardless of their functional hierarchy. The deviant stimuli induced theta-band power increases in the TONE condition but beta-band power decreases in the ACCENTUATIION condition, regardless of the timing of their acoustic cues. These results suggest that, in an unattentive state, the human brain can functionally disentangle hierarchically different levels of pitch variation, and the brain responses to these pitch variations are time-locked to the presence of the acoustic cues.

关键词： Unattended processing hierarchical processing Neural processing Lexical tone Sentence-level pitch MMN

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hierarchical artificial grammar processing engages Broca's area

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NEUROIMAGE 2008年第2期42卷 525-534页

作者： Bahlmann, Joerg Schubotz, Ricarda I. Friederici, Angela D. Max Planck Inst Human Cognit & Brain Sci D-04103 Leipzig Germany

The present fMRI study investigates the neural basis of hierarchical processing using two types of artificial grammars: one governed by rules of adjacent dependencies and the other by rules of hierarchical dependencies. The adjacent dependency sequences followed the rule (AB)(n), at which simple transitions between two types of syllable categories were generated (e.g. A(1)B(1)A(2)B(2)). The hierarchical syllable sequences. followed the rule A(n)B(n), generating a center-embedded structure (e.g. A(2)A(1)B(1)B(2)) the learning of which required the processing of hierarchical dependencies. When comparing the processing of hierarchical dependencies to adjacent dependencies, significantly higher activations were observed in Broca's area and the adjacent rim of the ventral premotor cortex (BA 44/6) in addition to some several other cortical and subcortical regions. These results indicate that Broca's area is part of a neural circuit that is responsible for the processing of hierarchical structures in an artificial grammar. (C) 2008 Elsevier Inc. All rights reserved.

关键词： artificial grammar fMRI hierarchical processing Broca's area language sequence processing

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Dynamic anticipatory processing of hierarchical sequential events: A common role for Broca's area and ventral premotor cortex across domains?

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CORTEX 2006年第4期42卷 499-502页

作者： Fiebach, Christian J. Schubotz, Ricarda I. Univ Calif Berkeley Helen Wills Neurosci Inst Berkeley CA 94720 USA Heidelberg Univ Neurocognit & Cognit Neurol Grp Inst Psychol Heidelberg Germany Heidelberg Univ Dept Neurol Heidelberg Germany Max Planck Inst Human Cognit & Brain Sci Dept Cognit Neurol Leipzig Germany

This paper proposes a domain-general model for the functional contribution of ventral premotor cortex (PMv) and adjacent Broca's area to perceptual, cognitive, and motor processing. We propose to understand this frontal region as a highly flexible sequence processor, with the PMv mapping sequential events onto stored structural templates and Broca's Area involved in more complex, hierarchical or hypersequential processing. This proposal is supported by reference to previous functional neuroimaging studies investigating abstract sequence processing and syntactic processing.

关键词： sequence processing syntactic processing hierarchical processing Broca's area ventral premotor cortex

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Automatic detection of targets using hierarchical spatial/temporal processing

Automatic detection of targets using hierarchical spatial/te...

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10th Meeting on Optical Engineering in Israel

作者： Haber, E Sylman, Y ElOp Electrooptics Industries Ltd. (Israel)

ISBN: (纸本)081942532X

An algorithm for automatic target detection has been developed. An image is processed using a pyramidal structure in a two stage process. Each frame is spatially filtered to identify potential target areas. The temporal behavior of blobs identified is analyzed;targets are declared where blobs exhibit motion consistent with targets of interest. Targets of different sizes are detected at different pyramid levels. A single target will usually be detected at several levels. Integration of information from the various levels is essential. Two data merging approaches were examined. The first projects blobs from each level to the pyramid base. Blobs exhibiting target-like behavior are extracted. The second innovative approach builds tracks on each level. Only blobs joined to tracks are projected to the base. Tracks are formed on these projections. Targets are declared on tracks that achieve a given quality. This hierarchical approach permits the system to operate with great sensitivity. False detections are eliminated at two stages. Most spurious blobs will not form tracks at the pyramid levels and will not be projected to the base. Tracking at the base eliminates others. Experimental results demonstrate high detection probability and low false alarm rate under a wide variety of conditions.

关键词： automatic target detection hierarchical processing image sequence processing tracking Kalman Filter

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SELF-ADAPTIVE PARALLEL processing NEURAL NETWORKS WITH IRREGULAR NODAL processing POWERS USING hierarchical PARTITIONING

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NEURAL NETWORK WORLD 2009年第6期19卷 657-680页

作者： Kala, Rahul Shukla, Anupam Tiwari, Ritu Indian Inst Informat Technol & Management Gwalior Dept Informat Technol Gwalior MP India

The architecture and working of the Artificial Neural Networks are an inspiration from the human brain. The brain due to its highly parallel nature and immense computational powers still remains the motivation for researchers. A single system-single processor approach is a highly unlikely way to model a neural network for large computational needs. Many approaches have been proposed that adopt a parallel implementation of ANNs. These methods do not consider the difference in processing powers of the constituting units and hence workload distribution among the nodes is not optimal. Human brain not always has equal processing power among the neurons. A person having disability in some part of brain may be able to perform every task with reduced capabilities. Disabilities weaken the processing of some parts. This inspires us to make a self-adaptive system of ANN that would optimally distribute computation among the nodes. The self-adaptive nature of the algorithm makes it possible for the algorithm to taper dynamic changes in node performance. We used data, node and layer partitioning in a hierarchical manner in order to evolve the most optimal architecture comprising of the best features of these partitioning techniques. The adaptive hierarchical architecture enables performance optimisation in whatever condition and problem the algorithm is used. The system was implemented and tested on 20 systems working in parallel. Besides, the computational speed-up, the algorithm was able to monitor changes in performance and adapt accordingly.

关键词： Artificial Neural Networks artificial brain parallel processing partitioning self-adaptive systems hierarchical processing node partitioning data partitioning layer partitioning

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Do the hemispheres differ in their preparation for global/local processing?

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EXPERIMENTAL BRAIN RESEARCH 2007年第3期176卷 525-531页

作者： Volberg, Gregor Huebner, Ronald Univ Regensburg Inst Expt Psychol D-93053 Regensburg Germany Univ Konstanz D-78457 Constance Germany

It has recently been suggested that hemispheric differences for global and local processing already occur in response to visual pre-cues that direct attention to a specific level. However, in the supporting studies cue information was confounded with the form of the cues. In order to dissolve the confound, we compared event-related brain potentials towards cues differing in form with those towards identically formed color cues. As a result, hemispheric differences were found only for the former cue type. The data thus show that the mere cue information does not produce hemispheric asymmetries associated with global/local target stimulus processing.

关键词： event-related potentials hemispheric asymmetry hierarchical processing attention

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Prism adaptation reverses the local processing bias in patients with right temporo-parietal junction lesions

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BRAIN 2009年第PT 6期132卷 1669-1677页

作者： Bultitude, Janet H. Rafal, Robert D. List, Alexandra Bangor Univ Sch Psychol Wolfson Ctr Clin & Cognit Neurosci Bangor LL57 2AS Gwynedd Wales

Lesions to the right temporo-parietal cortex commonly result in hemispatial neglect. Lesions to the same area are also associated with hyperattention to local details of a scene and difficulty perceiving the global structure. This local processing bias is an important factor contributing to neglect and may contribute to the higher prevalence of the disorder following right compared with left hemisphere strokes. In recent years, visuomotor adaptation to rightward-shifting prisms has been introduced as a promising treatment for hemispatial neglect. Explanations for these improvements have generally described a leftward realignment of attention, however, the present investigation provides evidence that prism adaptation reduces the local processing bias. Five patients with right temporal-parietal junction lesions were asked to identify the global or local levels of hierarchical figures before and after visuomotor adaptation to rightward-shifting prisms. Prior to prism adaptation the patients had difficulty ignoring the local elements when identifying the global component. Following prism adaptation, however, this pattern was reversed, with greater global interference during local level identification. The results suggest that prism adaptation may improve non-spatially lateralized deficits that contribute to the neglect syndrome.

关键词： hemispatial neglect visual attention prism adaptation hierarchical processing

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Decreasing predictability of visual motion enhances feed-forward processing in visual cortex when stimuli are behaviorally relevant

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BRAIN STRUCTURE & FUNCTION 2017年第2期222卷 849-866页

作者： Kellermann, Thilo Scholle, Ruben Schneider, Frank Habel, Ute Rhein Westfal TH Aachen Dept Psychiat Psychotherapy & Psychosomat Uniklin RWTH Aachen Pauwelsstr 30 D-52074 Aachen Germany JARA BRAIN Inst 1 Struct Funct Relationship D-52428 Julich Germany

Recent views of information processing in the (human) brain emphasize the hierarchical structure of the central nervous system, which is assumed to form the basis of a functional hierarchy. hierarchical predictive processing refers to the notion that higher levels try to predict activity in lower areas, while lower levels transmit a prediction error up the hierarchy whenever the predictions fail. The present study aims at testing hypothetical modulatory effects of unpredictable visual motion on forward connectivities within the visual cortex. Functional magnetic resonance imaging was acquired from 35 healthy volunteers while viewing a moving ball under three different levels of predictability. In two different runs subjects were asked to attend to direction changes in the ball's motion, where a button-press was required in one of these runs only. Dynamic causal modeling was applied to a network comprising V1, V5 and posterior parietal cortex in the right hemisphere. The winning model of a Bayesian model selection indicated an enhanced strength in the forward connection from V1 to V5 with decreasing predictability for the run requiring motor response. These results support the notion of hierarchical predictive processing in the sense of an augmented bottom-up transmission of prediction error with increasing uncertainty about motion direction. This finding may be of importance for promoting our understanding of trait characteristics in psychiatric disorders, as an increased forward propagation of prediction error is assumed to underlie schizophrenia and may be observable at early stages of the disease.

关键词： Effective connectivity Dynamic causal modeling (DCM) Predictive coding hierarchical processing Prediction error

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A functional magnetic resonance imaging study of local/global processing with stimulus presentation in the peripheral visual hemifields

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NEUROSCIENCE 2004年第1期124卷 113-120页

作者： Lux, S Marshall, JC Ritzl, A Weiss, PH Pietrzyk, U Shah, NJ Zilles, K Fink, GR Res Ctr Julich Inst Med D-52425 Julich Germany Univ Oxford Dept Clin Neurol Oxford OX2 6HE England Rhein Westfal TH Aachen Klinikum Dept Neurol D-52074 Aachen Germany Univ Wuppertal Dept Phys D-42119 Wuppertal Germany Univ Dusseldorf C & O Vogt Hirnforsch Inst D-40225 Dusseldorf Germany

When stimuli are presented in the left or right visual fields, hemispheric specialization for global and local processing in occipital areas is attenuated. Using functional magnetic resonance imaging, we investigated how this attenuation is compensated for when information must cross the corpus callosum to reach the areas specialized for global and local processing. We presented hierarchically nested letters (e.g. a large E made of smaller E's) to the right or the left visual hemifield while subjects fixated centrally. In half the trials, subjects indicated whether the global aspect and in the other half whether the local aspect of the stimulus matched a pre-specified target letter. Visual hemifield presentations showed the expected contralateral activations of occipital cortex. The main effects of locally or globally directed attention did not show any differential occipital activations, but the right anterior cingulate cortex was activated differentially during local processing. Region-of-interest-based analyses showed increased neural activity in left posterior occipital cortex during local processing when stimuli were presented in the left hemifield. During global processing with stimulus presentation to the right hemifield, the right posterior occipital cortex was activated. Activation of right anterior cingulate cortex during local processing is likely to reflect the suppression of global processing precedence in order to select correctly the local stimulus level. The activations in left (local) and right (global) occipital areas are likely to reflect the top-down augmentation of stimulus information that has been degraded by callosal crossing in order to access the hemisphere specialized for local or global processing. (C) 2004 IBRO. Published by Elsevier Ltd. All rights reserved.

关键词： hierarchical processing Navon figures precedence effect callosal crossing

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Multiple asynchronous stimulus- and task-dependent hierarchies (STDH) within the visual brain's parallel processing systems

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EUROPEAN JOURNAL OF NEUROSCIENCE 2016年第8期44卷 2515-2527页

作者： Zeki, Semir UCL Wellcome Lab Neurobiol London WC1E 6BT England

Results from a variety of sources, some many years old, lead ineluctably to a re-appraisal of the twin strategies of hierarchical and parallel processing used by the brain to construct an image of the visual world. Contrary to common supposition, there are at least three 'feed-forward' anatomical hierarchies that reach the primary visual cortex (V1) and the specialized visual areas outside it, in parallel. These anatomical hierarchies do not conform to the temporal order with which visual signals reach the specialized visual areas through V1. Furthermore, neither the anatomical hierarchies nor the temporal order of activation through V1 predict the perceptual hierarchies. The latter shows that we see (and become aware of) different visual attributes at different times, with colour leading form (orientation) and directional visual motion, even though signals from fast-moving, high-contrast stimuli are among the earliest to reach the visual cortex (of area V5). Parallel processing, on the other hand, is much more ubiquitous than commonly supposed but is subject to a barely noticed but fundamental aspect of brain operations, namely that different parallel systems operate asynchronously with respect to each other and reach perceptual endpoints at different times. This re-assessment leads to the conclusion that the visual brain is constituted of multiple, parallel and asynchronously operating task-and stimulus-dependent hierarchies (STDH);which of these parallel anatomical hierarchies have temporal and perceptual precedence at any given moment is stimulus and task related, and dependent on the visual brain's ability to undertake multiple operations asynchronously.

关键词： asynchronous processing dynamic parallelism hierarchical processing parallel processing visual cortex

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