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A Two-Stage Cascade Model of BOLD Responses in Human Visual Cortex

Kendrick N. Kay, Jonathan Winawer, Ariel Rokem, Aviv Mezer, Brian A. Wandell, Jörn Diedrichsen
2013 PLoS Computational Biology  
The model has a cascade architecture, consisting of two stages of linear and nonlinear operations.  ...  In this study, we develop a model that accepts an arbitrary band-pass grayscale image as input and predicts blood oxygenation level dependent (BOLD) responses in early visual cortex as output.  ...  Kriegeskorte for providing the object stimuli used in this study; A. Takahashi for spiral pulse sequence development; and M. Ben-Shachar, S. David, J. DiCarlo, K. Grill-Spector, T. Hastie, and A.  ... 
doi:10.1371/journal.pcbi.1003079 pmid:23737741 pmcid:PMC3667759 fatcat:iplqtc74tjbi3grxjmb2qro35i

Representation of Naturalistic Image Structure in the Primate Visual Cortex

J. Anthony Movshon, Eero P. Simoncelli
2014 Cold Spring Harbor Symposia on Quantitative Biology  
The perception of complex visual patterns emerges from neuronal activity in a cascade of areas in the primate cerebral cortex.  ...  The responses of neurons in the primary visual cortex, V1, are relatively insensitive to the statistical information in these textures.  ...  The perception of complex visual patterns emerges from neuronal activity in a cascade of areas in the primate cerebral cortex.  ... 
doi:10.1101/sqb.2014.79.024844 pmid:25943766 pmcid:PMC4800008 fatcat:bl4lar7v6feudpha3of73xw6ni

Uncertainty and Invariance in the Human Visual Cortex

Bosco S. Tjan, Vaia Lestou, Zoe Kourtzi
2006 Journal of Neurophysiology  
Uncertainty and invariance in the human visual cortex. . The way in which input noise perturbs the behavior of a system depends on the internal processing structure of the system.  ...  In particular, our findings provide novel evidence that occipitotemporal areas in the ventral visual pathway form a cascade of decision stages with increasing degree of signal uncertainty and feature invariance  ...  Contrast sensitivity in human visual areas and its relationship to object recognition.  ... 
doi:10.1152/jn.01367.2005 pmid:16723410 pmcid:PMC2699460 fatcat:53zbzesdczeunmh6ipna5bd5ze

Visual Mapping Using Blood Oxygen Level Dependent Functional Magnetic Resonance Imaging

Edgar A. DeYoe, Ryan V. Raut
2014 Neuroimaging clinics of North America  
Neurovascular uncoupling and its detection in visual cortex are key issues for the interpretation of fMRI results in patients with existing brain pathology.  ...  Synopsis Functional magnetic resonance imaging (fMRI) is used clinically to map visual cortex prior to brain surgery or other invasive treatments in order to achieve an optimal balance between therapeutic  ...  the BOLD fMRI signal in visually responsive brain areas.  ... 
doi:10.1016/j.nic.2014.08.001 pmid:25441501 pmcid:PMC4255289 fatcat:butcick4nzbkpn76iuvb2ugzr4

Motion opponency and transparency in the human middle temporal area

Javier O. Garcia, Emily D. Grossman
2009 European Journal of Neuroscience  
rate of primary visual cortex neurons.  ...  We find reduced BOLD amplitude for motion opponency throughout visual cortex, but weakened responses due to perceptual transparency that is most apparent only within the hMT+.  ...  temporal area; hMST+, human medial superior temporal area and surrounding areas; MT, middle temporal area; ROI, region of interest; V1, primary visual cortex.  ... 
doi:10.1111/j.1460-9568.2009.06893.x pmid:19723288 fatcat:mho7j2bw4ff3vcbhudcjpx2beq

Unifying Temporal Phenomena in Human Visual Cortex [article]

Jingyang Zhou, Noah C Benson, Kendrick Kay, Jonathan Winawer
2017 bioRxiv   pre-print
Neuronal responses in visual cortex show a diversity of complex temporal properties.  ...  We propose a model consisting of a linear stage, followed by history-dependent gain control.  ...  We also thank Josef Parvizi and the Stanford Human Intracranial Cognitive Electrophysiology Program for helping us with ECoG data acquisition for a prior paper, which was re-analyzed for this paper.  ... 
doi:10.1101/108639 fatcat:vnz6v653iveupjppw6la3ej6ha

Decoding Successive Computational Stages of Saliency Processing

Carsten Bogler, Stefan Bode, John-Dylan Haynes
2011 Current Biology  
Signals in early visual cortex and posterior intraparietal sulcus (IPS) correlated with graded saliency as defined by a computational saliency model.  ...  Some models assume that salient locations from a visual scene are encoded in a dedicated spatial saliency map [1, 2] .  ...  In pIPS, however, the BOLD response in each voxel was informative of the saliency in two or more quadrants.  ... 
doi:10.1016/j.cub.2011.08.039 pmid:21962709 fatcat:ogrtp7d3vvd5nhonil3rlrexma

Early Suppressive Mechanisms and the Negative Blood Oxygenation Level-Dependent Response in Human Visual Cortex

A. R. Wade, J. Rowland
2010 Journal of Neuroscience  
By measuring BOLD signals in human primary visual cortex while varying the baseline contrast levels in the region affected by the NBR, we tested three physiologically plausible computational models of  ...  However, these positive responses are frequently accompanied by reductions in the BOLD signal in adjacent regions of cortex.  ...  BOLD responses in cortex.  ... 
doi:10.1523/jneurosci.6260-09.2010 pmid:20371821 pmcid:PMC3523120 fatcat:at7nwq6eercpdie2oogujkdtqi

Experimental design and interpretation of functional neuroimaging studies of cognitive processes

David Caplan
2009 Human Brain Mapping  
It is not now known whether there are areas of cortex with higher percentages of inhibitory neurons. If there are, BOLD signal increases in these areas can be interpreted accordingly.  ...  I argue that certain designs in common use-in particular the contrast of qualitatively different representations that are processed at parallel stages of a functional architecture-can never identify the  ...  of the issues raised here and comments on earlier drafts of this article, and to the editors of Human Brain Mapping for suggestions regarding exposition and style.  ... 
doi:10.1002/hbm.20489 pmid:17979122 pmcid:PMC2612094 fatcat:vmmyl3bqpzd4zbdm3pi33fh24q

Multimodal Imaging Evidence for a Frontoparietal Modulation of Visual Cortex during the Selective Processing of Conditioned Threat

Nathan M. Petro, L. Forest Gruss, Siyang Yin, Haiqing Huang, Vladimir Miskovic, Mingzhou Ding, Andreas Keil
2017 Journal of Cognitive Neuroscience  
The resulting single trial steady-state visual evoked potential (ssVEP) amplitude was regressed against the whole-brain BOLD signal, resulting in a measure of ssVEP-BOLD coupling.  ...  Dynamic causal modeling analyses supported connectivity models in which heightened activity in peri-calcarine cortex for threat (CS+) arises from cortico-cortical top-down modulation, specifically from  ...  Acknowledgments This research was supported by grants from the National Institutes of Health (R01MH097320) and the Office of Naval Research (N00014-14-1-0542).  ... 
doi:10.1162/jocn_a_01114 pmid:28253082 pmcid:PMC5529037 fatcat:3sysbwbddbcszbltxucjlrir2m

Retinotopic organization of primary visual cortex in glaucoma: Comparing fMRI measurements of cortical function with visual field loss

Robert O. Duncan, Pamela A. Sample, Robert N. Weinreb, Christopher Bowd, Linda M. Zangwill
2007 Progress in retinal and eye research  
Neuronal degeneration has also been shown in a post-mortem human study of the optic nerve, LGN and visual cortex.  ...  The BOLD signal in human V1 is altered for POAG patients in a manner consistent with the loss of visual function.  ...  In this approach, two-dimensional visual space is projected onto the two-dimensional flattened cortex using the formula w ¼ k  log(z+a), where z is a complex number representing a point in visual space  ... 
doi:10.1016/j.preteyeres.2006.10.001 pmid:17126063 pmcid:PMC1940234 fatcat:kyw63ohfzveqpe5ofv3utbbmci

An image-computable model for the stimulus selectivity of gamma oscillations [article]

Dora Hermes, Natalia Petridou, Kendrick Kay, Jonathan Winawer
2019 bioRxiv   pre-print
To reconcile these findings and gain a better understanding of this signal, we developed a model that predicts gamma responses for arbitrary images and validated this model on data from visual cortex in  ...  Gamma responses are large for only a small subset of stimuli tested, and this pattern of responses (both data and model predictions) differs dramatically from fMRI BOLD signals and ECoG broadband (non-oscillatory  ...  The SOC 198 model is a two-stage LNN (Linear-Nonlinear-Nonlinear) cascade model.  ... 
doi:10.1101/583567 fatcat:bdmaz4ygmbcynlbcdetgguihrq

Nonlinear Aspects of the BOLD Response in Functional MRI

Alberto L. Vazquez, Douglas C. Noll
1998 NeuroImage  
The nonlinear characteristics of the BOLD response were assessed using a Laplacian linear system model cascaded with a broadening function.  ...  Linearity of the BOLD response was examined in the primary visual cortex for manipulations of the stimulus amplitude and duration.  ...  We thank Christopher Genovese for his feedback on the statistical analyses used in this work.  ... 
doi:10.1006/nimg.1997.0316 pmid:9558643 fatcat:diqg7ohfnjecto5qcmyjthzetm

Estimating Neural Signal Dynamics in the Human Brain

Christopher W. Tyler, Lora T. Likova
2011 Frontiers in Systems Neuroscience  
This is the published version of the paper. This version of the publication may differ from the final published version.  ...  , we will not have sufficient power to account for all the parameters of a quantitative model of the response behavior in human cortex.  ...  The responses from primary visual cortex (∼250 voxels) for a 1-h session from a typical subject are shown in Figure 5B .  ... 
doi:10.3389/fnsys.2011.00033 pmid:21713117 pmcid:PMC3112330 fatcat:n6ttytqw4vflzm5uqdmjes2cxy

Compressive Temporal Summation in Human Visual Cortex

Jingyang Zhou, Noah C. Benson, Kendrick N. Kay, Jonathan Winawer
2017 Journal of Neuroscience  
Population receptive field models have been successful in characterizing spatial encoding throughout the human visual pathways.  ...  Importantly, compressive temporal summation directly parallels earlier findings of compressive spatial summation in visual cortex describing responses to stimuli distributed across space.  ...  Discussion Summation and adaptation in visual cortex We report that temporal summation is subadditive throughout human visual cortex.  ... 
doi:10.1523/jneurosci.1724-17.2017 pmid:29192127 pmcid:PMC5777115 fatcat:pwdtkqtf55fibk5m2kghtcu5z4
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