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Pattern classification precedes region-average hemodynamic response in early visual cortex

Peter J. Kohler, Sergey V. Fogelson, Eric A. Reavis, Ming Meng, J. Swaroop Guntupalli, Michael Hanke, Yaroslav O. Halchenko, Andrew C. Connolly, James V. Haxby, Peter U. Tse
2013 NeuroImage  
In primary visual cortex (V1) stimulus information can be detected in the pattern of voxel responses more than a second before the average hemodynamic response of V1 deviates from baseline, and classification  ...  the average response across a given brain region.  ...  Conflict of interest The authors declare that the research was conducted in the absence of any actual or potential conflict of interest including any financial, personal or other relationships with other  ... 
doi:10.1016/j.neuroimage.2013.04.019 pmid:23587693 fatcat:ooj6ghz2ibgzpdbdtopz24yssu

Auditory Cortex Encodes the Perceptual Interpretation of Ambiguous Sound

N. Kilian-Hutten, G. Valente, J. Vroomen, E. Formisano
2011 Journal of Neuroscience  
in the superior temporal cortex, most prominently on the posterior bank of the left Heschl's gyrus and sulcus and in the adjoining left planum temporale.  ...  To overcome this problem, we used functional magnetic resonance imaging (fMRI) in humans and pattern-recognition analysis to identify activation patterns that encode the perceptual interpretation of physically  ...  In all GLMs, predictor time courses were convolved with a hemodynamic response function (where both the BOLD response and undershoot are modeled by a gamma function) to adjust for the hemodynamic delay  ... 
doi:10.1523/jneurosci.4572-10.2011 pmid:21289180 pmcid:PMC6623724 fatcat:cajdvphy6fb7rmewpur7vpvr2q

Decoding Working Memory of Stimulus Contrast in Early Visual Cortex

Y. Xing, T. Ledgeway, P. V. McGraw, D. Schluppeck
2013 Journal of Neuroscience  
Furthermore, classification generalized from perceived to remembered stimuli and vice versa, implying that the corresponding pattern of responses in early visual cortex were highly consistent.  ...  Recent evidence from electrophysiology and neuroimaging studies, however, suggests that early visual cortex may also play a role in retaining stimulus representations in memory for short periods.  ...  role of early visual cortex in working memory.  ... 
doi:10.1523/jneurosci.3754-12.2013 pmid:23785144 pmcid:PMC3722490 fatcat:evztkozjy5fzjnfcwfgvdma6ky

Less Is More: Expectation Sharpens Representations in the Primary Visual Cortex

Peter Kok, Janneke F.M. Jehee, Floris P. de Lange
2012 Neuron  
We find that while perceptual expectation reduces the neural response amplitude in the primary visual cortex (V1), it improves the stimulus representation in this area, as revealed by MVPA.  ...  visual cortex of human volunteers.  ...  Third, binning trials on the basis of angle differences revealed no differences in MVPA orientation classification in any of the early visual cortex regions for ''large orientation difference versus small  ... 
doi:10.1016/j.neuron.2012.04.034 pmid:22841311 fatcat:yhgk4vqqt5bfxix46h7cpaao6a

Sight and Sound Converge to Form Modality-Invariant Representations in Temporoparietal Cortex

K. Man, J. T. Kaplan, A. Damasio, K. Meyer
2012 Journal of Neuroscience  
While several areas became activated in response to both auditory and visual stimulation, only the neural patterns recorded in a region around the posterior part of the superior temporal sulcus displayed  ...  In this functional magnetic resonance imaging study of human subjects, we first identified brain areas that responded to both visual and auditory stimuli and then used crossmodal multivariate pattern analysis  ...  Successful classification of the response patterns was taken to infer content specificity.  ... 
doi:10.1523/jneurosci.2342-12.2012 pmid:23175818 pmcid:PMC3667662 fatcat:ia7lv57yvndvna5gfirq7jh57e

Discriminability of numerosity-evoked fMRI activity patterns in human intra-parietal cortex reflects behavioral numerical acuity

Gabriel Lasne, Manuela Piazza, Stanislas Dehaene, Andreas Kleinschmidt, Evelyn Eger
2018 Cortex  
Sample numerosities were decodable in both early visual and intra-parietal cortex with approximately equal accuracy on average.  ...  fraction measured prior to scanning showed greater discriminability of fMRI activity patterns in intraparietal cortex, and more specifically, the right LIP region).  ...  The detailed pattern of classification performance is displayed in Figure 2A Across all pairwise comparisons, decoding performance was on average 57.1% correct in early visual cortex and 56.7 % correct  ... 
doi:10.1016/j.cortex.2018.03.008 pmid:29655488 fatcat:3doxinw5dnamhcxnotrpv2zfbe

Discriminability of numerosity-evoked fMRI activity patterns in human intra-parietal cortex reflects behavioral numerical acuity [article]

Gabriel Lasne, Manuela Piazza, Stanislas Dehaene, Andreas Kleinschmidt, Evelyn Eger
2017 bioRxiv   pre-print
Sample numerosities were decodable in both early visual and intraparietal cortex with approximately equal accuracy on average.  ...  fraction measured prior to scanning showed greater discriminability of fMRI activity patterns in intraparietal cortex, and more specifically, the right LIP region).  ...  The detailed pattern of classification performance is displayed in Figure 2A Across all pairwise comparisons, decoding performance was on average 57.1% correct in early visual cortex and 56.7 % correct  ... 
doi:10.1101/198002 fatcat:6qzdecpseng4bns463mvcrvyfe

Linking pattern completion in the hippocampus to predictive coding in visual cortex

Nicholas C Hindy, Felicia Y Ng, Nicholas B Turk-Browne
2016 Nature Neuroscience  
We show that such memory-based expectations in human visual cortex are related to the hippocampal mechanism of pattern completion. At least two kinds of expectations guide perception.  ...  Hierarchical models of predictive coding explain how such expectations arise, with feedback signals carrying information about expected levels of activity in earlier layers of visual cortex 1-3 .  ...  representations in early visual cortex.  ... 
doi:10.1038/nn.4284 pmid:27065363 pmcid:PMC4948994 fatcat:7wupipa555gblfa7dg7h3vlovq

Neural correlates of own- and other-race face perception: Spatial and temporal response differences

Vaidehi Natu, David Raboy, Alice J. O'Toole
2011 NeuroImage  
The pattern-classification results indicate the early availability of categorical information about own-versus other-race face status in the spatial pattern of neural activity.  ...  A pattern classifier, applied to voxels across a broad range of ventral temporal areas, discriminated the brain activity maps elicited in response to Asian versus Caucasian faces in the brains of both  ...  The time sensitivity of neural discrimination suggests that the pattern of brain regions activated in response to own-and other-race faces differs most in early processing.  ... 
doi:10.1016/j.neuroimage.2010.10.006 pmid:20937393 fatcat:o6ts37rtsbezfn2pul24jcx6vm

Age differences in neural distinctiveness revealed by multi-voxel pattern analysis

Joshua Carp, Joonkoo Park, Thad A. Polk, Denise C. Park
2011 NeuroImage  
Finally, we investigated whether older adults can compensate for altered processing in visual cortex by encoding stimulus information across larger numbers of voxels within the visual cortex or in regions  ...  Further, we report that age differences in neural distinctiveness extend beyond the ventral visual cortex: older adults also showed decreased distinctiveness in early visual cortex, inferior parietal cortex  ...  early visual cortex in aging humans.  ... 
doi:10.1016/j.neuroimage.2010.04.267 pmid:20451629 pmcid:PMC2962693 fatcat:skxdgqjd6vhelbhjyttixociia

Spatially Invariant Coding of Numerical Information in Functionally Defined Subregions of Human Parietal Cortex

E. Eger, P. Pinel, S. Dehaene, A. Kleinschmidt
2013 Cerebral Cortex  
hemifields in parietal, but not early visual cortex.  ...  In a delayed number comparison paradigm with laterally presented numerosities, parietal cortex discriminated between numerosities better than early visual cortex, and discrimination generalized across  ...  Figure 2A shows classification performance for early visual cortex (left) and parietal cortex (right), where classification performance appears to be better on average when training and testing in the  ... 
doi:10.1093/cercor/bht323 pmid:24293562 fatcat:fpulmwwp25c2te3ii2tfbxryke

Reading-induced shifts of perceptual speech representations in auditory cortex

Milene Bonte, Joao M. Correia, Mirjam Keetels, Jean Vroomen, Elia Formisano
2017 Scientific Reports  
We show that it is possible to retrieve the text-induced perceptual interpretation from fMRI activity patterns in the posterior superior temporal cortex.  ...  In this paradigm, the pairing of visual text and ambiguous speech sounds shifts (i.e. recalibrates) the perceptual interpretation of the ambiguous sounds in subsequent auditory-only trials.  ...  We thank Miriam Löhr and Selma Kemmerer for assistance in data acquisition and Giancarlo Valente for advice on statistical analysis of the behavioural data.  ... 
doi:10.1038/s41598-017-05356-3 pmid:28698606 pmcid:PMC5506038 fatcat:at7q4elowveupjxuvtutbpgqpu

Decoding the future from past experience: learning shapes predictions in early visual cortex

Caroline D. B. Luft, Alan Meeson, Andrew E. Welchman, Zoe Kourtzi
2015 Journal of Neurophysiology  
Decoding the future from past experience: learning shapes predictions in early visual cortex.  ...  responses in early visual areas (Kamitani and Tong 2005) .  ...  and Albright 2007) and early visual (Bosch et al. 2014) cortex.  ... 
doi:10.1152/jn.00753.2014 pmid:25744884 pmcid:PMC4432681 fatcat:p5rr7gdiwvgu5b2ec3fwjjmz5y

Fine-scale activity patterns in high-level visual areas encode the category of invisible objects

P. Sterzer, J. D. Haynes, G. Rees
2008 Journal of Vision  
Overall responses of high-level ventral visual areas to two different types of invisible object stimuli (faces and houses) were very weak and did not differ in amplitude.  ...  These findings demonstrate the presence of category-specific information in high-level visual areas during profound interocular suppression of object stimuli that can only be retrieved when the fine-scale  ...  It should be noted that our experimental paradigm and scanning procedure was not originally designed to assess response patterns in early visual cortex and we cannot therefore attribute the patterns to  ... 
doi:10.1167/8.15.10 pmid:19146294 fatcat:3gfvv6z3wvhl3fhzupgebikzwa

Reward processing in the value-driven attention network: reward signals tracking cue identity and location

Brian A. Anderson
2016 Social Cognitive and Affective Neuroscience  
preceding cue in IPS, while early visual cortex represented both location and identity.  ...  tail, lateral occipital complex (LOC) and early visual cortex] and intraparietal sulcus (IPS).  ...  The funder played no role in the reported research beyond financial support. Conflict of interest. None declared.  ... 
doi:10.1093/scan/nsw141 pmid:27677944 pmcid:PMC5390735 fatcat:4dmz5aibnngexciiln7sahk2fm
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