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Feature Coding with a Statistically Independent Cortical Representation [chapter]

Roberto Valerio, Rafael Navarro, Bart M. ter Haar Romeny, Luc Florack
2003 Lecture Notes in Computer Science  
In this communication, we show that such a scheme permits an efficient coding of natural image features.  ...  This nonlinear process extracts significant, statistically independent, visual events in the image.  ...  Coding with a Statistically Independent Cortical Representation 47           + − + = ∑ ∑ ≠ ≠ ) ( 2 exp ) ( 2 1 }) { | ( 2 2 2 2 2 i j j ij i i i j j ij i j i c b a c c b a c c p π (1) In the  ... 
doi:10.1007/3-540-44935-3_4 fatcat:sf5ejnohizfx7mt2iqkdh6lvym

Neural Representation and the Cortical Code

R. Christopher deCharms, Anthony Zador
2000 Annual Review of Neuroscience  
This article defines and reviews how information is represented in the firing rates and temporal patterns of populations of cortical neurons, with a particular emphasis on how this information mediates  ...  The cerebral cortex is one of the primary seats of the internal representations maintained and used in perception, memory, decision making, motor control, and subjective experience, but the basic coding  ...  The Independent-Coding Hypothesis Independent coding suggests that each cortical neuron represents a separate signal.  ... 
doi:10.1146/annurev.neuro.23.1.613 pmid:10845077 fatcat:pzt5hhnmjbf2xcxocsv3r4l5qq

Information coding in the cortex by independent or coordinated populations

R. C. deCharms
1998 Proceedings of the National Academy of Sciences of the United States of America  
The Independent Coding Hypothesis. Independent coding suggests that each cortical neuron represents a separate signal.  ...  Cortical neurons in both sensory and motor systems are broadly tuned for features of the world, with a given sensory stimulus or motor act engaging very large numbers of cortical neurons (4, 6, 10, 13  ... 
doi:10.1073/pnas.95.26.15166 pmid:9860939 pmcid:PMC33931 fatcat:4l27qxqh6bcflipwpxl7vdzcyy

Multivoxel codes for representing and integrating acoustic features in human cortex [article]

Ediz Sohoglu, Sukhbinder Kumar, Maria Chait, Timothy Griffiths
2019 bioRxiv   pre-print
In the superior temporal plane, changes in multivoxel activity due to frequency were largely invariant with respect to AM rate (and vice versa), consistent with an independent representation.  ...  Our findings support the notion that primary auditory cortex can represent component acoustic features in an independent fashion and suggest a role for parietal cortex in feature integration and the structuring  ...  Thus, 441 this ROI analysis suggests that in sub-fields of auditory cortex, cortical 442 activation patterns show a mixture of components: a strong independent code 443 and a weak integrated code.  ... 
doi:10.1101/730234 fatcat:t4q3zngczvcdzcy67sz5jdw5le

Multivoxel codes for representing and integrating acoustic features in human cortex

Ediz Sohoglu, Sukhbinder Kumar, Maria Chait, Timothy D. Griffiths
2020 NeuroImage  
Direct between-region comparisons show that whereas independent coding of frequency weakened with increasing levels of the hierarchy, such a progression for AM and integrated coding was less fine-grained  ...  In the superior temporal plane, changes in multivoxel activity due to frequency were largely invariant with respect to AM rate (and vice versa), consistent with an independent representation.  ...  to which cortical activity patterns show evidence for 1) 441 independent coding of frequency, in which the influence of frequency was 442 invariant with respect to AM, 2) independent coding of AM, in  ... 
doi:10.1016/j.neuroimage.2020.116661 pmid:32081785 pmcid:PMC7339141 fatcat:denh63j7infazjrmqbphfizezm

Efficient image representations and features

Michael Dorr, Eleonora Vig, Erhardt Barth, Bernice E. Rogowitz, Thrasyvoulos N. Pappas, Huib de Ridder
2013 Human Vision and Electronic Imaging XVIII  
A key research question has been: given the (statistical) properties of natural images, what are the most efficient and perceptually relevant image representations, what are the most prominent and descriptive  ...  similar wavelet transforms; the brain uses a sparse code, engineers are currently excited about sparse coding and compressed sensing.  ...  statistical independence.  ... 
doi:10.1117/12.2002300 dblp:conf/hvei/DorrVB13 fatcat:dg66jzktzraarhekg6ro2pbqqa

A mechanism for the cortical computation of hierarchical linguistic structure

Andrea E. Martin, Leonidas A. A. Doumas, David Poeppel
2017 PLoS Biology  
linking hypothesis between linguistic representation and cortical computation.  ...  Such redundancy in the cortical and machine signals is indicative of formal and mechanistic alignment between representational structure building and "cortical" oscillations.  ...  In a system with variable-value independence, statistics about the association between representations can still play an important role, but those statistics are not the sole basis of the representational  ... 
doi:10.1371/journal.pbio.2000663 pmid:28253256 pmcid:PMC5333798 fatcat:654avixjpnfplpxy3p5auz5ln4

Robust Multifactor Speech Feature Extraction Based on Gabor Analysis

Qiang Wu, Liqing Zhang, Guangchuan Shi
2011 IEEE Transactions on Audio, Speech, and Language Processing  
His current research interests cover computational theory for cortical networks, brain signal processing and brain-computer interfaces, perception and cognition computing models, statistical learning,  ...  In this paper, we investigate the speech feature extraction problem in a noisy environment and propose a novel approach based on Gabor filtering and tensor factorization.  ...  Intuitively, the projection matrices preserve the statistical characteristic of clean speech data and transform the cortical representation into a sparse feature space.  ... 
doi:10.1109/tasl.2010.2070495 fatcat:ztrdicj57jfsvp6dw52rou62ui

Dynamic and Task-Dependent Encoding of Speech and Voice by Phase Reorganization of Cortical Oscillations

M. Bonte, G. Valente, E. Formisano
2009 Journal of Neuroscience  
This transient and goal-dependent realignment of neuronal responses to physically different external events provides a robust cortical coding mechanism for forming and processing abstract representations  ...  Vowel categorization leads to a significant temporal realignment of responses to the same vowel, e.g., /a/, independent of who pronounced this vowel, whereas speaker categorization leads to a significant  ...  Both the transient and taskdependent realignment of neuronal responses (EEG) and the spatially distributed cortical fingerprints (fMRI) provide robust cortical coding mechanisms for forming abstract representations  ... 
doi:10.1523/jneurosci.3694-08.2009 pmid:19211877 pmcid:PMC6666288 fatcat:zfjz35w6z5eq5dst72qw7iqed4

Decoding Articulatory Features from fMRI Responses in Dorsal Speech Regions

J. M. Correia, B. M. B. Jansma, M. Bonte
2015 Journal of Neuroscience  
regions, suggesting the representation of sensorimotor information.  ...  Using a passive listening paradigm and multivariate decoding of single-trial fMRI responses to spoken syllables, we investigated brain-based generalization of articulatory features (place and manner of  ...  All maps are projected onto the group-aligned cortical surface with a minimum cluster size of 3 mm 2 and statistically thresholded ( p Ͻ 0.05).  ... 
doi:10.1523/jneurosci.0977-15.2015 pmid:26558773 pmcid:PMC6605359 fatcat:qabhifh7fvhidcxtdluzhbur4u

Population coding of affect across stimuli, modalities and individuals

Junichi Chikazoe, Daniel H Lee, Nikolaus Kriegeskorte, Adam K Anderson
2014 Nature Neuroscience  
Although ventral temporal and anterior insular cortices supported valence codes specific to vision and taste, both the medial and lateral orbitofrontal cortices (OFC) maintained a valence code independent  ...  Representational mapping of population activity evoked by complex scenes and basic tastes in humans revealed a neural code supporting a continuous axis of pleasant-to-unpleasant valence.  ...  Consistent with their substantial independence, visual feature, animacy and valence scores were largely uncorrelated, sharing 0.2% (visual features and animacy, all R 2 = 0.002), 1.0% (visual features  ... 
doi:10.1038/nn.3749 pmid:24952643 pmcid:PMC4317366 fatcat:bcdkhprq7naylmx3h5obyrpt7y

Hierarchical representations in the auditory cortex

Tatyana O Sharpee, Craig A Atencio, Christoph E Schreiner
2011 Current Opinion in Neurobiology  
A common solution that is thought to be employed by diverse sensory systems is to create hierarchical representations of increasing complexity and tolerance.  ...  Here we review the recent progress that begins to probe the hierarchy of auditory representations, and the computational approaches that can be helpful in achieving this feat.  ...  Accordingly, cortical neurons are capable of carrying multiple signals via different codes with regard to AM.  ... 
doi:10.1016/j.conb.2011.05.027 pmid:21704508 pmcid:PMC3223290 fatcat:3xaptqdnonhvfiyjidzeqe3ilq

Visual working memory is independent of the cortical spacing between memoranda [article]

William J Harrison, Paul M Bays
2017 biorxiv/medrxiv   pre-print
due to their nearby cortical representations.  ...  The sensory recruitment hypothesis states that visual short term memory is maintained in the same visual cortical areas that initially encode a stimulus' features.  ...  It is possible that 576 non-spatial features can be bound according to a conjunctive code that links features with 577 their temporal order, but neurophysiological evidence for such a model is scarce.  ... 
doi:10.1101/216341 fatcat:wpyoye3olrcmrmpblapmoi4myq

Generalizable dimensions of human cortical auditory processing of speech in natural soundscapes: A data-driven ultra high field fMRI approach

Moritz Boos, Jörg Lücke, Jochem W. Rieger
2021 NeuroImage  
These results were derived with few a-priori assumptions and provide a detailed and computationally reproducible account of the cortical activity in the temporal lobe elicited by the processing of speech  ...  One is most sensitive to complex auditory features present in speech, another to complex auditory features and fast temporal modulations, that are not specific to speech, and one codes mainly sound level  ...  Murphy (2012)) to statistically infer a set 174 of auditory features (basis functions in sparse coding terminology), optimized to 175 represent natural sounds with a sparse code in which only few basis  ... 
doi:10.1016/j.neuroimage.2021.118106 pmid:33991696 fatcat:f6nlfeefqfatrnbssqddiq2bhi

The Opponent Channel Population Code of Sound Location Is an Efficient Representation of Natural Binaural Sounds

Wiktor Młynarski, Matthias Bethge
2015 PLoS Computational Biology  
This study connects neuronal coding of the auditory space with natural stimulus statistics and generates new experimental predictions.  ...  Moreover, results presented here suggest that cortical regions with seemingly different functions may implement the same computational strategy-efficient coding.  ...  would like to thank Timm Lochmann for many interesting remarks and proofreading of the manuscript, Philipp Benner and Charles Cadieu for helpful discussions, Mikaella Sarrou and Maria Młynarska for help with  ... 
doi:10.1371/journal.pcbi.1004294 pmid:25996373 pmcid:PMC4440638 fatcat:aqreujfxhjdjtgkkkk7brjgwkm
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