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Visual learning for perceptual and categorical decisions in the human brain

Zoe Kourtzi
2010 Vision Research  
Here, we review the role of visual learning and experience-dependent plasticity in shaping decisions.  ...  We propose that learning plays an important role in translating sensory experiences to decisions and actions by shaping neural representations across cortical circuits in a task-dependent manner.  ...  areas to the topdown selection of familiar objects in the prefrontal cortex.  ... 
doi:10.1016/j.visres.2009.09.025 pmid:19818361 fatcat:6y75u4x5cnhejgx5hnsdysieu4

The Neural Dynamics of Attentional Selection in Natural Scenes

D. Kaiser, N. N. Oosterhof, M. V. Peelen
2016 Journal of Neuroscience  
The human visual system can only represent a small subset of the many objects present in cluttered scenes at any given time, such that objects compete for representation.  ...  A sensor-space searchlight analysis revealed that this early attention bias was localized to lateral occipitotemporal cortex, reflecting top-down modulation of visual processing.  ...  object processing in lateral occipitotemporal cortex.  ... 
doi:10.1523/jneurosci.1385-16.2016 pmid:27733605 fatcat:nl477maykjaz5hwlni3kogvgoi

Task-Dependent Warping of Semantic Representations During Search for Visual Action Categories [article]

Mo Shahdloo, Emin Çelik, Burcu A Urgen, Jack L. Gallant, Tolga Çukur
2021 bioRxiv   pre-print
Object and action perception in cluttered dynamic natural scenes relies on efficient allocation of limited brain resources to prioritize the attended targets over distractors.  ...  It has been suggested that during visual search for objects, distributed semantic representation of hundreds of object categories is warped to expand the representation of targets.  ...  Acknowledgements Funding This work was supported in part by a Marie Curie Actions Career Integration Grant (PCIG13-GA-2013-618101), by a European Molecular Biology Organisation Installation Grant (IG  ... 
doi:10.1101/2021.06.17.448789 fatcat:jkhycqwigzhhbdkgq65s2u7wyi

Learning and neural plasticity in visual object recognition

Zoe Kourtzi, James J DiCarlo
2006 Current Opinion in Neurobiology  
Supported by funding from The Biotechnology and Biological Sciences Research Council (BBSRC) BB/D52199X/1 to Z Kourtzi and The National Eye Institute R01-EY014970 to JJ DiCarlo.  ...  Acknowledgements We would like to thank S Engel, N Kanwisher, H Op de Beeck and M Riesenhuber for comments and discussion on the manuscript.  ...  scenes across visual occipitotemporal areas to the top-down selection of familiar objects in the prefrontal cortex.  ... 
doi:10.1016/j.conb.2006.03.012 pmid:16563736 fatcat:2726vuzmabd5tczy35nq6abqw4

Distributed Neural Plasticity for Shape Learning in the Human Visual Cortex

Zoe Kourtzi, Lisa R Betts, Pegah Sarkheil, Andrew E Welchman, Robert Desimone
2005 PLoS Biology  
However, the neural implementation of object learning across stages of visual analysis in the human brain remains largely unknown.  ...  In contrast, learning of prominent pop-out shapes is mediated by associations at higher occipitotemporal areas that support sparser coding of the critical features for target recognition.  ...  ZK and AEW wrote the paper.  ... 
doi:10.1371/journal.pbio.0030204 pmid:15934786 pmcid:PMC1150289 fatcat:wjakpcwezfcrxfkf5fd6bpnjhi

Neural Representations for Object Perception: Structure, Category, and Adaptive Coding

Zoe Kourtzi, Charles E. Connor
2011 Annual Review of Neuroscience  
Object perception is one of the most remarkable capacities of the primate brain.  ...  Owing to the large and indeterminate dimensionality of object space, the neural basis of object perception has been difficult to study and remains controversial.  ...  Furthermore, recent work suggests that the representations of object categories in the temporal cortex are modulated by task demands (Koida & Komatsu 2007) and experience (e.g., Op de Beeck et al. 2006  ... 
doi:10.1146/annurev-neuro-060909-153218 pmid:21438683 fatcat:j6nwnuwy75d4nfnhvvtkky4x3q

A neural basis for real-world visual search in human occipitotemporal cortex

M. V. Peelen, S. Kastner
2011 Proceedings of the National Academy of Sciences of the United States of America  
Author contributions: M.V.P. and S.K. designed research; M.V.P. performed research; M.V.P. analyzed data; and M.V.P. and S.K. wrote the paper. The authors declare no conflict of interest.  ...  This work was supported by National Institutes of Health Grants R01-EY017699 and R01-MH064043 and National Science Foundation Grant BCS-1025149.  ...  Consistent with the present findings, it was hypothesized that SOS may maintain an updated representation of scene context to modulate and facilitate object processing in visual cortex (29) .  ... 
doi:10.1073/pnas.1101042108 pmid:21730192 pmcid:PMC3141945 fatcat:zvad35cfj5egnapyytaqv2jewe

Shape Saliency Modulates Contextual Processing in the Human Lateral Occipital Complex

Christian F. Altmann, Arne Deubelius, Zoe Kourtzi
2004 Journal of Cognitive Neuroscience  
& Visual context influences our perception of target objects in natural scenes. However, little is known about the analysis of context information and its role in shape perception in the human brain.  ...  We investigated whether the human lateral occipital complex (LOC), known to be involved in the visual analysis of shapes, also processes information about the context of shapes within cluttered scenes.  ...  Acknowledgments We thank the group of Wolfgang Grodd at the University Clinics in Tübingen for providing the MRI facilities, and Lisa Betts, Elisabeth Huberle, Jan Jastorff, and Andrew Welchman for useful  ... 
doi:10.1162/089892904970825 pmid:15200707 fatcat:il36pvshazejdprcsmrqac7j6e

Attentional control of the processing of neutral and emotional stimuli

Luiz Pessoa, Sabine Kastner, Leslie G Ungerleider
2002 Cognitive Brain Research  
Functional brain imaging studies reveal that biasing signals due to selective attention can modulate neural activity in visual cortex not only in the presence but also in the absence of visual stimulation  ...  Although the competition among stimuli for representation is ultimately resolved within visual cortex, the source of top-down biasing signals likely derives from a distributed network of areas in frontal  ...  Sci. 4 (2000) 215-222. modulated components in occipitotemporal cortex occur [9] C. Cavada, P.S.  ... 
doi:10.1016/s0926-6410(02)00214-8 pmid:12433381 fatcat:dpx7agpcybg3haqk364z3n7nte

Biased competition in semantic representation during natural visual search

Mohammad Shahdloo, Emin Çelik, Tolga Çukur
2019 NeuroImage  
Humans divide their attention among multiple visual targets in daily life, and visual search can get more difficult as the number of targets increases.  ...  Yet, it is unknown whether attentional modulation of semantic representations are consistent with this hypothesis when viewing cluttered, dynamic natural scenes.  ...  Acknowledgement The authors gratefully acknowledge Salman U.H. Dar for his assistance in writing the manuscript, and Kübra Keskin for her assistance in the analyses.  ... 
doi:10.1016/j.neuroimage.2019.116383 pmid:31785423 fatcat:tprnvyyeqvanzarkvjlziozmwa

Contextual and Spatial Associations Between Objects Interactively Modulate Visual Processing

Genevieve L Quek, Marius V Peelen
2020 Cerebral Cortex  
Over right occipitotemporal sites, this signal was larger for typically positioned object streams, indicating that spatial configuration facilitated the extraction of the objects' contextual association  ...  The differential response to nonassociated pairs (measurable at 0.625 Hz in 28/37 participants) served as an index of contextual integration, reflecting the association of object identities in each pair  ...  The authors would like to acknowledge A. Theodorou, L. Billen, N. Parrella, and M. Picó Cabiró for their assistance with data collection. Conflict of Interest. There are no conflicts of interest.  ... 
doi:10.1093/cercor/bhaa197 pmid:32754744 pmcid:PMC7609942 fatcat:afdwiu26uzholbwqbasv3icd54

Parametric Coding of the Size and Clutter of Natural Scenes in the Human Brain

Soojin Park, Talia Konkle, Aude Oliva
2014 Cerebral Cortex  
walls) and functional "clutter" (the organization and quantity of objects that fill up the space).  ...  These data provide support for a property-based representation of spaces, distributed across multiple scene-selective regions of the cerebral cortex.  ...  Notes We thank the Athinoula A. Martinos Imaging Center at McGovern Institute for Brain Research, MIT for help with fMRI data acquisition. Conflict of Interest: None declared.  ... 
doi:10.1093/cercor/bht418 pmid:24436318 pmcid:PMC4459284 fatcat:r7lnxohqzff6np6uxmjcaezlbi

Mechanisms of Visual Attention in the Human Cortex

Sabine Kastner and Leslie G. Ungerleider
2000 Annual Review of Neuroscience  
Functional brain imaging studies reveal that, both in the absence and in the presence of visual stimulation, biasing signals due to selective attention can modulate neural activity in visual cortex in  ...  A typical scene contains many different objects that, because of the limited processing capacity of the visual system, compete for neural representation.  ...  Carol Colby, Robert Desimone, Peter De Weerd, John Duncan, and John Reynolds for valuable discussions, and Mark Pinsk and Christine Rey-Hipolito for help with the preparation of the manuscript.  ... 
doi:10.1146/annurev.neuro.23.1.315 pmid:10845067 fatcat:qskfhm4v6bekzbpgwhgdpzzs3i

Neuronal integration in visual cortex elevates face category tuning to conscious face perception

J. Fahrenfort, T. Snijders, K. Heinen, S. van Gaal, S. Scholte, V. Lamme
2013 Journal of Vision  
The human brain has the extraordinary capability to transform cluttered sensory input into distinct object representations.  ...  Here we show that visible and invisible faces produce similar category-selective responses in the ventral visual cortex.  ...  The human brain has the extraordinary capability to transform cluttered sensory input into distinct object representations.  ... 
doi:10.1167/13.9.1033 fatcat:2mqqddqlanbxjhaawgfjsdmqd4

Neuronal integration in visual cortex elevates face category tuning to conscious face perception

J. J. Fahrenfort, T. M. Snijders, K. Heinen, S. van Gaal, H. S. Scholte, V. A. F. Lamme
2012 Proceedings of the National Academy of Sciences of the United States of America  
The human brain has the extraordinary capability to transform cluttered sensory input into distinct object representations.  ...  Here we show that visible and invisible faces produce similar category-selective responses in the ventral visual cortex.  ...  The human brain has the extraordinary capability to transform cluttered sensory input into distinct object representations.  ... 
doi:10.1073/pnas.1207414110 pmid:23236162 pmcid:PMC3535630 fatcat:rpxp4o6onzfxvlgw4jqg722tuy
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