Grouping of image fragments in primary visual cortex

Sugita, Yoichi

doi:10.1038/45785

Cited by 215 publications

(171 citation statements)

References 20 publications

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“…despite no physical stimulus change within the receptive field ( Figure 2). Neurons in area V1 did not respond to ICs, though subsequent work provides 6 (controversial) evidence for such responses ( [2,13,14]; see also [15] for data from cats). These types of results were taken as support for feed-forward mechanisms of IC sensitivity in V1/V2.…”

Section: Single-unit Studiesmentioning

confidence: 97%

Illusory contours: a window onto the neurophysiology of constructing perception

Murray

Herrmann

2013

Trends in Cognitive Sciences

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Abstract:Seeing seems effortless, despite needing to segregate and integrate visual information that varies in its quality, quantity, and location. The extent to which seeing passively recapitulates the external world is challenged by phenomena such as illusory contours, an example of visual completion whereby borders are perceived despite their physical absence in the image. Instead, visual completion and seeing are increasingly conceived as active processes, dependent on information exchange across neural populations. How this is instantiated in the brain remains controversial. Divergent models emanate from single-unit and population-level electrophysiology, neuroimaging, and neurostimulation studies. We reconcile discrepant findings from different methods and disciplines, and underscore the importance of taking into account spatio-temporal brain dynamics in generating models of brain function and perception. Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation 1 Highlights Illusory contours exemplify core challenges for perception and binding  Competing models stem from diverse neurophysiologic metrics in animals and humans  Consideration of spatio-temporal brain dynamics reconciles these differences 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 2 AbstractSeeing seems effortless, despite needing to segregate and integrate visual information that varies in its quality, quantity, and location. The extent to which seeing passively recapitulates the external world is challenged by phenomena such as illusory contours, an example of visual completion whereby borders are perceived despite their physical absence in the image.Instead, visual completion and seeing are increasingly conceived as active processes, dependent on information exchange across neural populations. How this is instantiated in the brain remains controversial. Divergent models emanate from single-unit and population-level electrophysiology, neuroimaging, and neurostimulation studies. We reconcile discrepant findings from different methods and disciplines, and underscore the importance of taking into account spatio-temporal brain dynamics in generating models of brain function and perception. KeywordsVisual perception; perceptual completion; binding; object recognition; illusory contour; neuroimaging 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 In what follows, we provide a review of these developments as they pertain to Single-unit StudiesPsychology differentiates sensation from perception (Box 1). Sensation reflects the neural representation of physical properties of stimuli, whereas perception refers to consci...

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Section: Single-unit Studiesmentioning

confidence: 97%

Illusory contours: a window onto the neurophysiology of constructing perception

Murray

Herrmann

2013

Trends in Cognitive Sciences

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“…Though many long-range lateral and feedback connections may be modulatory, some may be driving (e.g. Fiorani, et al, 1992;Sugita, 1999;Fitzpatrick, 1996;Muckli and Petro, 2013). There is also in vitro evidence that, in the cortex of mice, V1 and V2 have both driving and modulatory connections in both directions (De Pasquale and Sherman, 2011), as do auditory regions A1 and A2 (Covic and Sherman, 2011).…”

Section: Contextual Modulation Is Widespread Throughout Many Regions mentioning

confidence: 99%

On the functions, mechanisms, and malfunctions of intracortical contextual modulation

Phillips

Clark

Silverstein

2015

Neuroscience & Biobehavioral Reviews

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A broad neuron-centric conception of contextual modulation is reviewed and re-assessed in the light of recent neurobiological studies of amplification, suppression, and synchronization. Behavioural and computational studies of perceptual and higher cognitive functions that depend on these processes are outlined, and evidence that those functions and their neuronal mechanisms are impaired in schizophrenia is summarized. Finally, we compare and assess the long-term biological functions of contextual modulation at the level of computational theory as formalized by the theories of coherent infomax and free energy reduction. We conclude that those theories, together with the many empirical findings reviewed, show how contextual modulation at the neuronal level enables the cortex to flexibly adapt the use of its knowledge to current circumstances by amplifying and grouping relevant activities and by suppressing irrelevant activities.

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“…We can study feedback signals by isolating them from the feedforward inputs by partially 78 occluding the image. The V1 representation of occluded regions of the visual field contains contextual 79 information (Ban et al, 2013;Shushruth, 2011;Smith and Muckli, 2010;Sugita, 1999) fed back to the 80 superficial layers (Muckli et al, 2015). Using a partial occlusion paradigm (Smith and Muckli, 2010 …”

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confidence: 99%

Cortical feedback signals generalise across different spatial frequencies of feedforward inputs

2018

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Primary visual cortex (V1) has small receptive fields and processes feedforward information at a fine-18 grained spatial scale, whereas higher visual areas have larger, spatially invariant receptive fields. Therefore, 19 feedback could provide coarse information about the global scene structure or alternatively recover fine-20 grained structure by targeting small receptive fields in V1. We tested if feedback signals generalise across 21 different spatial frequencies of feedforward inputs, or if they are tuned to the spatial scale of the visual 22 scene. Using a partial occlusion paradigm, functional magnetic resonance imaging (fMRI) and multivoxel 23 pattern analysis (MVPA) we investigated whether feedback to V1 contains coarse or fine-grained 24 information by manipulating the spatial frequency of the scene surround outside an occluded image portion. 25We show that feedback transmits both coarse and fine-grained information as it carries information about 26 both low (LSF) and high spatial frequencies (HSF

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Grouping of image fragments in primary visual cortex

Cited by 215 publications

References 20 publications

Illusory contours: a window onto the neurophysiology of constructing perception

Illusory contours: a window onto the neurophysiology of constructing perception

On the functions, mechanisms, and malfunctions of intracortical contextual modulation

Cortical feedback signals generalise across different spatial frequencies of feedforward inputs

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