Extra-receptive Field Research Articles

Visually induced γ band rhythm in spatial summation beyond the receptive field in mouse primary visual cortex.

Recent studies in many kinds of mammals have established the existence of multiple γ rhythms in the cerebral cortex subserving different functions. In the primary visual cortex (V1), visually induced γ rhythms are dependent on stimulus features. However, experimental findings of γ power induced by varying the size of the drifting grating are inconsistent. Here, we reinvestigated the spatial summation properties of visually induced spike and γ rhythm activities in mouse V1. Our results show that drifting sinusoidal grating stimuli mainly induce 2 γ band rhythms, including a low-frequency band (25-45Hz) and a high-frequency band (55-75Hz). Unlike previous findings, we discovered that visually induced γ power could also exhibit extrareceptive field (ERF) modulatory properties. The modulation by ERF stimulation could be either suppressive, countersuppressive, or nonsuppressive, mostly similar to the local spike activity. Moreover, further analysis of the neuron group exhibiting surround suppression in both spike and γ activity revealed that the strength of the surround suppression and the receptive field size showed moderate correlations between measurements by spike and γ rhythm activity. Our findings improve the understanding of the characteristics and neural mechanisms of induced γ rhythms in visual spatial summation.

The Contrast Response Function of the Inhibitory Extra-Receptive Field Cells

Using extracellular recording methods,the authors measured the contrast response function of the inhibitory extra-receptive field of 41 cells in the cat primary visual cortex,when stimulating the classical receptive field(CRF) only or simultaneously stimulating CRF and extra-receptive field(ERF).The results showed that a large contrast stimulus with the preferred orientation that covered ERF and CRF resulted in the increment in dynamic range of contrast response function and the decrement in contrast gain and response gain.However,the discontinuity between CRF and ERF in stimulation orientation largely removed the inhibitory effects of ERF of some cells,and resulted in the increment of the dynamic range of the contrast response function and increment of contrast gain and response gain.

Neurotransmitter Receptor Bases of the Long-Rage Interactions of Cat Striate Cortical Neurons Revealed by In-Vivo Intracellular Injection

In the primary visual cortex, activity of neurons evoked by stimuli within the classical receptive field (CRF) can be modulated by stimuli in the extra-receptive field (ERF). This modulating effect can be facilitatory (F-ERF) or inhibitory (I-ERF) that play different roles in visual information processing. Little is known on the neurotransmitter receptor bases of the two types of long-range interactions. Using in vivo intracellular injection technique, combined with the technique of immunocytochemistry, we have studied the immunocytochemical features of the F-ERF and I-ERF neurons. Significant differences were found in type, density and distribution of neurotransmitter receptors between the two types of neurons. F-ERF neurons have densely distributed Glu2/3 receptors and relatively small amount of GABAA receptors on the surface of proximal dendrites and cell body, and the reverse is true for I-ERF neurons. As the Glu2/3 receptors are the main targets of excitatory synaptic input and the GABAA receptors are the main targets of inhibibory synaptic input, the differences in receptor characteristics between the I-ERF and F-ERF neurons may underlie the distinct long-range modulation effects of the two types of neurons.

Giacomo Rizzolatti

Giacomo Rizzolatti

Morphological Bases of Suppressive and Facilitative Spatial Summation in the Striate Cortex of the Cat

In V1 of cats and monkeys, activity of neurons evoked by stimuli within the receptive field can be modulated by stimuli in the extra-receptive field (ERF). This modulating effect can be suppressive (S-ERF) or facilitatory (F-ERF) and plays different roles in visual information processing. Little is known about the cellular bases underlying the different types of ERF modulating effects. Here, we focus on the morphological differences between the S-ERF and F-ERF neurons. Single unit activities were recorded from V1 of the cat. The ERF properties of each neuron were assessed by area-response functions using sinusoidal grating stimuli. On completion of the functional tests, the cells were injected intracellularly with biocytin. The labeled cells were reconstructed and morphologically characterized in terms of the ERF modulation effects. We show that the vast majority of S-ERF neurons and F-ERF neurons are pyramidal cells and that the two types of cells clearly differ in the size of the soma, in complexity of dendrite branching, in spine size and density, and in the range of innervations of the axon collaterals. We propose that different pyramidal cell phenotypes reflect a high degree of specificity of neuronal connections associated with different types of spatial modulation.

Modeling Stereopsis via Markov Random Field

Markov random field (MRF) and belief propagation have given birth to stereo vision algorithms with top performance. This article explores their biological plausibility. First, an MRF model guided by physiological and psychophysical facts was designed. Typically an MRF-based stereo vision algorithm employs a likelihood function that reflects the local similarity of two regions and a potential function that models the continuity constraint. In our model, the likelihood function is constructed on the basis of the disparity energy model because complex cells are considered as front-end disparity encoders in the visual pathway. Our likelihood function is also relevant to several psychological findings. The potential function in our model is constrained by the psychological finding that the strength of the cooperative interaction minimizing relative disparity decreases as the separation between stimuli increases. Our model is tested on three kinds of stereo images. In simulations on images with repetitive patterns, we demonstrate that our model could account for the human depth percepts that were previously explained by the second-order mechanism. In simulations on random dot stereograms and natural scene images, we demonstrate that false matches introduced by the disparity energy model can be reliably removed using our model. A comparison with the coarse-to-fine model shows that our model is able to compute the absolute disparity of small objects with larger relative disparity. We also relate our model to several physiological findings. The hypothesized neurons of the model are selective for absolute disparity and have facilitative extra receptive field. There are plenty of such neurons in the visual cortex. In conclusion, we think that stereopsis can be implemented by neural networks resembling MRF.

Figure-ground segregation and spatial phase tuning of extra-receptive field of V1 neurons in awake monkey

Figure-ground segregation and spatial phase tuning of extra-receptive field of V1 neurons in awake monkey

Modulatory effect of intra- and extra-receptive field stimuli on local field potentials and single unit activity in the dorsal lateral geniculate nucleus

Event Abstract Back to Event Modulatory effect of intra- and extra-receptive field stimuli on local field potentials and single unit activity in the dorsal lateral geniculate nucleus Alice Rokszin1, Péter Gombkötő1*, Agnes Ilona Farkas1, Antal Berényi1, Gyorgy Benedek1 and Attila Nagy1 1 Department of Physiology, University of Szeged, Hungary We performed extracellular recording of single unit activity (SUA) and local field potentials (LFP) in the dorsal lateral geniculate nucleus (LGNd) of anesthetized, immobilized cats. The goal of the present study was to compare the information content of the SUA and the LFP elicited by using of intra- and extra-receptive field stimuli. For visual stimulation static light spots of different diameters (1-20 deg in 5 steps) were applied. To estimate the correlation between the two aspects of activity, the power spectra of the LFPs in the range of 0.1-40 Hz were analyzed and correlated to the SUA. We found two frequency domains in correlation with the gross neuronal response. A phasic, positive, short-latency LFP component that is correlating with the SUA at a mean frequency of 12 Hz existed during the onset and the offset of the stimulus. After this phasic response, a slowly attenuating negative LFP waveform at a mean frequency of 5 Hz was observed with long latency, which showed no correlation with the SUA. Based upon our results we conclude that in contrast with the SUA the LFP can be elicited also by using extra-receptive field stimuli. Moreover the negative tonic pattern in the LFP contains additional information to the SUA, which might be generated by intragenicular neuronal circuits. +: equal contribution Conference: 12th Meeting of the Hungarian Neuroscience Society, Budapest, Hungary, 22 Jan - 24 Jan, 2009. Presentation Type: Poster Presentation Topic: Developmental neurobiology and subcortical functions Citation: Rokszin A, Gombkötő P, Farkas A, Berényi A, Benedek G and Nagy A (2009). Modulatory effect of intra- and extra-receptive field stimuli on local field potentials and single unit activity in the dorsal lateral geniculate nucleus. Front. Syst. Neurosci. Conference Abstract: 12th Meeting of the Hungarian Neuroscience Society. doi: 10.3389/conf.neuro.01.2009.04.057 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Feb 2009; Published Online: 27 Feb 2009. * Correspondence: Péter Gombkötő, Department of Physiology, University of Szeged, Szeged, Hungary, peti@phys.szote.u-szeged.hu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Alice Rokszin Péter Gombkötő Agnes Ilona Farkas Antal Berényi Gyorgy Benedek Attila Nagy Google Alice Rokszin Péter Gombkötő Agnes Ilona Farkas Antal Berényi Gyorgy Benedek Attila Nagy Google Scholar Alice Rokszin Péter Gombkötő Agnes Ilona Farkas Antal Berényi Gyorgy Benedek Attila Nagy PubMed Alice Rokszin Péter Gombkötő Agnes Ilona Farkas Antal Berényi Gyorgy Benedek Attila Nagy Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Correlation between single unit activity and local field potentials

Event Abstract Back to Event Correlation between single unit activity and local field potentials Agnes Ilona Farkas1*, Péter Gombkötő1, Alice Rokszin1, Gyorgy Benedek1, Attila Nagy1 and Antal Berényi1 1 Department of Physiology, University of Szeged, Hungary The mechanism of encoding of visual information involves complex interactions between intrinsic neuronal discharge and dendrosomatic potentials generated by multiple types of synapses. The correlation between local field potentials (LFPs) and single-unit activity (SUA) has already been studied in the visual cortex and other cortical structures but less interest was focused on subcortical areas. The dorsal lateral geniculate nucleus (LGNd) is one of the thalamic visual relay nuclei in which this correlation was not investigated. We have, therefore obtained simultaneous multielectrode SUA and LFP recordings using four microelectrodes from the LGNd of three anesthetized, immobilized artificially ventilated cats. The stimulus was firstly presented in the receptive field of each unit; afterwards all four receptive fields were simultaneously stimulated. We have analyzed the signal of each electrode in each condition. We found that responses were present in both LFPs and SUA in many cases even if extra-receptive field stimulus was applied, which can be due to intragenicular connections and spreading potentials from neighboring cells. We found a characteristic positive LFP response with short latency which was in phase with the SUA of the “ON”, or „ON-OFF” cells. Some consequent, out-of-phase negative late components of the LFP were also found that showed no correlation with the SUA pattern. Despite of this finding these components were also different among the electrode positions that recorded “ON” or “OFF” or “ON-OFF” neurons, which can be explained with a domination of one cell type in one electrode area. Conference: 12th Meeting of the Hungarian Neuroscience Society, Budapest, Hungary, 22 Jan - 24 Jan, 2009. Presentation Type: Poster Presentation Topic: Research on the cerebral cortex and related structures Citation: Farkas A, Gombkötő P, Rokszin A, Benedek G, Nagy A and Berényi A (2009). Correlation between single unit activity and local field potentials. Front. Syst. Neurosci. Conference Abstract: 12th Meeting of the Hungarian Neuroscience Society. doi: 10.3389/conf.neuro.01.2009.04.192 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 06 Mar 2009; Published Online: 06 Mar 2009. * Correspondence: Agnes Ilona Farkas, Department of Physiology, University of Szeged, Szeged, Hungary, agiko12@freemail.hu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Agnes Ilona Farkas Péter Gombkötő Alice Rokszin Gyorgy Benedek Attila Nagy Antal Berényi Google Agnes Ilona Farkas Péter Gombkötő Alice Rokszin Gyorgy Benedek Attila Nagy Antal Berényi Google Scholar Agnes Ilona Farkas Péter Gombkötő Alice Rokszin Gyorgy Benedek Attila Nagy Antal Berényi PubMed Agnes Ilona Farkas Péter Gombkötő Alice Rokszin Gyorgy Benedek Attila Nagy Antal Berényi Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Spatial Phase Sensitivity of V1 Neurons in Alert Monkey

The activity of V1 neurons evoked by stimuli within the classical receptive field (CRF) is known to be modulated by stimuli in the surrounding field, the extra-receptive field (ERF). By varying the relative spatial phase (RSP) between a central grating presented in the CRF and a surround grating in the ERF, we studied the contextual modulation in V1 neurons of alert monkeys (Macaca mulata). Results from two monkeys show that most of the V1 neurons with suppressive ERF are sensitive to the RSP, and the degree of sensitivity is strongly dependent on the strength of ERF suppression. This sensitivity is maximal when the RSP is generated at or near CRF/ERF boundary, but is observed over the entire ERF. Interestingly, the suppressive effect of the surround grating can be largely abolished by inserting a narrow gap between the center and surround gratings or by a phase displacement between them corresponding to <10% of the CRF diameter. These properties of V1 neurons may serve important perceptual functions.

Clustered Organization of Neurons with Similar Extra-Receptive Field Properties in the Primary Visual Cortex

The primary visual cortex is organized into clusters of cells having similar classical receptive field (CRF) properties. Nonclassical, extra-receptive fields (ERFs) can either inhibit or facilitate the response elicited by stimulation within the CRF. Here, we report that in the primary visual cortex of cat, neurons with similar inhibitory or facilitatory ERF properties are also grouped into clusters. These clusters are randomly distributed in all cortical layers, with no detectable relationship with orientation and ocular dominance columns. This functional organization of neurons with respect to ERF properties may allow an efficient processing of global visual information.

Contextual Modulation in Primary Visual Cortex

We studied extra-receptive field contextual modulation in area V1 of awake, behaving macaque monkeys. Contextual modulation was studied using texture displays in which texture covering the receptive field (RF) was the same in all trials, but the perceptual context of this texture could vary depending on the configuration of extra-RF texture elements. We found robust contextual modulation when disparity, color, luminance, and orientation cues variously defined a textured figure centered on the RF of V1 neurons. We found contextual modulation to have a spatial extent of approximately 8 to 10 degrees diameter parafoveally. Contextual modulation correlated with perceptual experience of both binocularly rivalrous texture displays and of displays with a simple example of surface occlusion. We found contextual modulation in V1 to have a characteristic latency of 80-100 msec after stimulus onset, potentially allowing feedback from extrastriate areas to underlie to this effect.

Areal influences on complex cells in cat striate cortex: stimulus-specificity of width and length summation

In single neurones recorded from the striate cortex of cats anaesthetized with N2O/O2/halothane, receptive field dimensions, length specificity and areal extent of drive were assessed for different classes of visual stimuli. Receptive fields were mapped as rectangular minimum response fields (MRFs). Spatial summation along the axis of preferred orientation was assessed: for moving bars whose length was varied (length summation); and for height variation of a square-wave grating patch against a uniform grey background, or a patch of moving texture against a stationary background of similar texture. In complementary tests a moving square-wave grating background was progressively occluded by a uniform grey foreground mask of variable height; or a mask of stationary texture of variable height progressively occluded a background of moving texture. In parallel measurements, the width of grating or textured patches or masks was varied whilst maintaining height constant. Broadly speaking, the areal influence of each class of stimulus was comparable, and distinct from extra-receptive field phenomena in evoking responses from within the receptive field, but not from surrounding areas. The masking paradigm provided the most sensitive measure of receptive field height and width. However, in some neurones length summation, the degree of end-stopping, and the directional bias depended critically on the stimulus configuration used. Length summation tended to be more dramatic for short bars than for gratings. Length summation for texture was significantly more pronounced than for an oriented bar in special and in intermediate complex neurones. By contrast, endstopping was typically less intense for gratings than for bars, and least pronounced for texture. Because of stimulus specificity, complex neurones assigned to particular functional subgroups on the basis of their response to oriented bars may exhibit quite different patterns of behaviour for other classes of stimuli.

Modulation of lateral geniculate nucleus cell responsiveness by visual activation of the corticogeniculate pathway

A radial grating stimulus was used to assess the effect of stimulation of the region beyond the classical surround of monkey lateral geniculate nucleus (LGN) receptive fields. The effect was measured by the differences in the responsiveness of the LGN cell center to small flashing spots between two conditions: (1) grating stationary or (2) grating rotating. The grating was present only in regions beyond the classical center and surround. The rotating grating produced changes in the flash-evoked spike response but not in the spontaneous activity in about half of the X cells and all of the Y cells. The direction of the effect was independent of the sign of the receptive field center. In a control experiment, cryogenic blockade of striate cortex reversed the effect in all cells tested. The grating effect was still present for cells having fields in that part of visual space beyond the region represented by the cooled cortical area. The effect was not a result of activation of classical extra-receptive field influences, since cells showing the effect did not exhibit shift or periphery effects or outer disinhibitory surrounds. The effect was not seen in recordings from intrageniculate retinal axons. We conclude that the radial grating effects LGN cell responsivity by activation of the corticogeniculate pathway.

Response properties of superior colliculus units: effects of extra-receptive field stimuli

Response properties of superior colliculus units: effects of extra-receptive field stimuli