Journal articles: 'Retinotopic'

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Yang, Zhiyong, David J. Heeger, and Eyal Seidemann. "Rapid and Precise Retinotopic Mapping of the Visual Cortex Obtained by Voltage-Sensitive Dye Imaging in the Behaving Monkey." Journal of Neurophysiology 98, no. 2 (August 2007): 1002–14. http://dx.doi.org/10.1152/jn.00417.2007.

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Retinotopy is a fundamental organizing principle of the visual cortex. Over the years, a variety of techniques have been used to examine it. None of these techniques, however, provides a way to rapidly characterize retinotopy, at the submillimeter range, in alert, behaving subjects. Voltage-sensitive dye imaging (VSDI) can be used to monitor neuronal population activity at high spatial and temporal resolutions. Here we present a VSDI protocol for rapid and precise retinotopic mapping in the behaving monkey. Two monkeys performed a fixation task while thin visual stimuli swept periodically at a high speed in one of two possible directions through a small region of visual space. Because visual space is represented systematically across the cortical surface, each moving stimulus produced a traveling wave of activity in the cortex that could be precisely measured with VSDI. The time at which the peak of the traveling wave reached each location in the cortex linked this location with its retinotopic representation. We obtained detailed retinotopic maps from a region of about 1 cm2 over the dorsal portion of areas V1 and V2. Retinotopy obtained during <4 min of imaging had a spatial precision of 0.11–0.19 mm, was consistent across experiments, and reliably predicted the locations of the response to small localized stimuli. The ability to rapidly obtain precise retinotopic maps in behaving monkeys opens the door for detailed analysis of the relationship between spatiotemporal dynamics of population responses in the visual cortex and perceptually guided behavior.

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Sayres, Rory, and Kalanit Grill-Spector. "Relating Retinotopic and Object-Selective Responses in Human Lateral Occipital Cortex." Journal of Neurophysiology 100, no. 1 (July 2008): 249–67. http://dx.doi.org/10.1152/jn.01383.2007.

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What is the relationship between retinotopy and object selectivity in human lateral occipital (LO) cortex? We used functional magnetic resonance imaging (fMRI) to examine sensitivity to retinal position and category in LO, an object-selective region positioned posterior to MT along the lateral cortical surface. Six subjects participated in phase-encoded retinotopic mapping experiments as well as block-design experiments in which objects from six different categories were presented at six distinct positions in the visual field. We found substantial position modulation in LO using standard nonobject retinotopic mapping stimuli; this modulation extended beyond the boundaries of visual field maps LO-1 and LO-2. Further, LO showed a pronounced lower visual field bias: more LO voxels represented the lower contralateral visual field, and the mean LO response was higher to objects presented below fixation than above fixation. However, eccentricity effects produced by retinotopic mapping stimuli and objects differed. Whereas LO voxels preferred a range of eccentricities lying mostly outside the fovea in the retinotopic mapping experiment, LO responses were strongest to foveally presented objects. Finally, we found a stronger effect of position than category on both the mean LO response, as well as the distributed response across voxels. Overall these results demonstrate that retinal position exhibits strong effects on neural response in LO and indicates that these position effects may be explained by retinotopic organization.

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Tu, Yanshuai, Duyan Ta, Zhong-Lin Lu, and Yalin Wang. "Topology-preserving smoothing of retinotopic maps." PLOS Computational Biology 17, no. 8 (August 2, 2021): e1009216. http://dx.doi.org/10.1371/journal.pcbi.1009216.

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Retinotopic mapping, i.e., the mapping between visual inputs on the retina and neuronal activations in cortical visual areas, is one of the central topics in visual neuroscience. For human observers, the mapping is obtained by analyzing functional magnetic resonance imaging (fMRI) signals of cortical responses to slowly moving visual stimuli on the retina. Although it is well known from neurophysiology that the mapping is topological (i.e., the topology of neighborhood connectivity is preserved) within each visual area, retinotopic maps derived from the state-of-the-art methods are often not topological because of the low signal-to-noise ratio and spatial resolution of fMRI. The violation of topological condition is most severe in cortical regions corresponding to the neighborhood of the fovea (e.g., < 1 degree eccentricity in the Human Connectome Project (HCP) dataset), significantly impeding accurate analysis of retinotopic maps. This study aims to directly model the topological condition and generate topology-preserving and smooth retinotopic maps. Specifically, we adopted the Beltrami coefficient, a metric of quasiconformal mapping, to define the topological condition, developed a mathematical model to quantify topological smoothing as a constrained optimization problem, and elaborated an efficient numerical method to solve the problem. The method was then applied to V1, V2, and V3 simultaneously in the HCP dataset. Experiments with both simulated and real retinotopy data demonstrated that the proposed method could generate topological and smooth retinotopic maps.

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Rajimehr, Reza, Natalia Y. Bilenko, Wim Vanduffel, and Roger B. H. Tootell. "Retinotopy versus Face Selectivity in Macaque Visual Cortex." Journal of Cognitive Neuroscience 26, no. 12 (December 2014): 2691–700. http://dx.doi.org/10.1162/jocn_a_00672.

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Retinotopic organization is a ubiquitous property of lower-tier visual cortical areas in human and nonhuman primates. In macaque visual cortex, the retinotopic maps extend to higher-order areas in the ventral visual pathway, including area TEO in the inferior temporal (IT) cortex. Distinct regions within IT cortex are also selective to specific object categories such as faces. Here we tested the topographic relationship between retinotopic maps and face-selective patches in macaque visual cortex using high-resolution fMRI and retinotopic face stimuli. Distinct subregions within face-selective patches showed either (1) a coarse retinotopic map of eccentricity and polar angle, (2) a retinotopic bias to a specific location of visual field, or (3) nonretinotopic selectivity. In general, regions along the lateral convexity of IT cortex showed more overlap between retinotopic maps and face selectivity, compared with regions within the STS. Thus, face patches in macaques can be subdivided into smaller patches with distinguishable retinotopic properties.

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Fitzgibbon, T., and B. E. Reese. "Organization of retinal ganglion cell axons in the optic fiber layer and nerve of fetal ferrets." Visual Neuroscience 13, no. 5 (September 1996): 847–61. http://dx.doi.org/10.1017/s095252380000910x.

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AbstractPrevious authors have hypothesized that retinotopic projections may be influenced by ‘preordering’ of the axons as they grow towards their targets. In some nonmammalian species, axons are reorganized at or near the optic nerve head to establish a retinotopic order. Data are ambiguous concerning the retinotopy of the mammalian retinal nerve fiber layer and whether fibers become reorganized at the optic nerve head. We have examined this question in fetal and newborn ferrets (Mustela putorius furo) by comparing the arrangement of axons in the retinal nerve fiber layer with that in the optic nerve. Dil or DiA crystals were implanted into fixed tissue in the innermost layers of the retinal periphery, or at a location midway between the periphery and the optic nerve head. Fluorescence labelling was examined in 100–200 μm Vibratome sections, or the eyecup and nerve were photooxidized and 1–2 μm longitudinal or transverse sections were examined. Regardless of fetal age, eccentricity or quadrant of the implant site, a segregation of labelled peripheral axons from unlabelled central ones was not detected within the nerve fiber layer. Axons coursed into the nerve head along the margin of their retinal quadrant of origin, often entering the optic nerve as a radial wedge, thus preserving a rough map of retinal circumference. However, peripheral axons were in no way restricted to the peripheral (nor central) portions of the nerve head or nerve, indicating that the optic axons do not establish a map of retinal eccentricity. Our results demonstrate that (1) the nerve fiber layer is retinotopic only with respect to circumferential position and (2) optic axons are not actively reorganized to establish a retinotopic ordering at the nerve head. The present results suggest that any degree of order present within the optic nerve is a passive consequence of combining the fascicles of the retinal nerve fiber layer; optic axons are not instructed to establish, nor constrained to maintain, a retinotopic order within the optic nerve.

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Noory, Babak, Michael H. Herzog, and Haluk Ogmen. "Retinotopy of visual masking and non-retinotopic perception during masking." Attention, Perception, & Psychophysics 77, no. 4 (March 14, 2015): 1263–84. http://dx.doi.org/10.3758/s13414-015-0844-2.

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Choung, Oh-hyeon, Marc Lauffs, Haluk Ögmen, and Michael Herzog. "How unconscious retinotopic processing influences conscious non-retinotopic perception." Journal of Vision 18, no. 10 (September 1, 2018): 292. http://dx.doi.org/10.1167/18.10.292.

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Lauffs, Marc M., Oh-Hyeon Choung, Haluk Öğmen, and Michael H. Herzog. "Unconscious retinotopic motion processing affects non-retinotopic motion perception." Consciousness and Cognition 62 (July 2018): 135–47. http://dx.doi.org/10.1016/j.concog.2018.03.007.

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STIRLING, R. V., S. A. DUNLOP, and L. D. BEAZLEY. "Electrophysiological evidence for transient topographic organization of retinotectal projections during optic nerve regeneration in the lizard, Ctenophorus ornatus." Visual Neuroscience 16, no. 4 (July 1999): 681–93. http://dx.doi.org/10.1017/s0952523899164083.

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In the lizard, Ctenophorus ornatus, anatomical studies have revealed that optic axons regenerate to visual centers within 2 months of nerve crush but that, from the outset, the regenerated projections lack topographic order (Beazley et al., 1997; Dunlop et al., 1997b). Here we assess the functional topography of the regenerated retinotectal projections by electrophysiological recording of extracellular multiunit responses to visual stimulation and by observing the lizards' ability to capture live prey. At the completion of the electrophysiology, DiI was applied locally to the retina and the topography of the tectal projection later assessed. Electrophysiology revealed that, at 2–4.2 months, responses were weak and habituated readily; no retinotopic order was detected. Between 4.5–6 months, responses were more reliable and the majority of lizards displayed a crude retinotopic order, especially in the ventro-temporal to dorso-nasal retinal axis. Although responses were variable between 6–9 months, they tended to be more reliable again thereafter. However, from 6–18 months, the projection consistently lacked topography with many retinal regions projecting to each tectal locus. Lizards, including those with electrophysiological evidence of crude retinotopy, were consistently unable to capture live prey using the experimental eye. Labelling with DiI confirmed the absence of anatomical retinotopy throughout. Taken together, the electrophysiological and anatomical data indicate that retinotopically appropriate axon terminals (or parts thereof) are transiently active whilst inappropriately located ones are silent. Presumably in lizard map-making cues fade with time and/or the mechanisms are lacking to stabilize and refine the ephemeral map. Moreover, the transient retinotopy is insufficient for useful visual function.

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Cavanagh, P., and A. O. Holcombe. "Non-retinotopic crowding." Journal of Vision 7, no. 9 (March 19, 2010): 338. http://dx.doi.org/10.1167/7.9.338.

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OTAKI, Sho, Sota WATANABE, and Kazuo FUJITA. "Non-retinotopic processing in humans vs. retinotopic processing in pigeons." Proceedings of the Annual Convention of the Japanese Psychological Association 76 (September 11, 2012): 1AMA61. http://dx.doi.org/10.4992/pacjpa.76.0_1ama61.

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Hsieh, P. J., E. Vul, and N. Kanwisher. "Recognition Alters the Spatial Pattern of fMRI Activation in Early Retinotopic Cortex." Journal of Neurophysiology 103, no. 3 (March 2010): 1501–7. http://dx.doi.org/10.1152/jn.00812.2009.

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Early retinotopic cortex has traditionally been viewed as containing a veridical representation of the low-level properties of the image, not imbued by high-level interpretation and meaning. Yet several recent results indicate that neural representations in early retinotopic cortex reflect not just the sensory properties of the image, but also the perceived size and brightness of image regions. Here we used functional magnetic resonance imaging pattern analyses to ask whether the representation of an object in early retinotopic cortex changes when the object is recognized compared with when the same stimulus is presented but not recognized. Our data confirmed this hypothesis: the pattern of response in early retinotopic visual cortex to a two-tone “Mooney” image of an object was more similar to the response to the full grayscale photo version of the same image when observers knew what the two-tone image represented than when they did not. Further, in a second experiment, high-level interpretations actually overrode bottom-up stimulus information, such that the pattern of response in early retinotopic cortex to an identified two-tone image was more similar to the response to the photographic version of that stimulus than it was to the response to the identical two-tone image when it was not identified. Our findings are consistent with prior results indicating that perceived size and brightness affect representations in early retinotopic visual cortex and, further, show that even higher-level information—knowledge of object identity—also affects the representation of an object in early retinotopic cortex.

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Reese, Benjamin E., and Gary E. Baker. "Changes in fiber organization within the chiasmatic region of mammals." Visual Neuroscience 9, no. 6 (December 1992): 527–33. http://dx.doi.org/10.1017/s0952523800001772.

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AbstractIntroductionClassical views of the optic chiasm maintain four propositions about the retinofugal pathways: (1) each optic nerve contains a retinotopic representation of its respective retinal surface; (2) this retinotopic map in the nerve is the basis for the subsequent segregation of the decussating from the non-decussating fibers; (3) this retinotopy in the nerve is also the basis for the presence of retinotopy found within the half-retinal maps in the optic tracts; and (4) the half-retinal maps from each optic nerve are brought together within the chiasm to yield a unified, binocularly congruent, map in the optic tract (Brodal, 1969; DukeElder, 1961; Polyak, 1957; Wolff, 1940). The appeal of this classical view is in its simplicity, based on the assumption that the retinofugal pathway should replicate the sensory surface along its course. We now know that each of these four propositions is incorrect, and that the error is not one simply of degree or extent (Guillery, 1982, 1991). Rather, the above description of the visual pathway is fundamentally flawed because it has failed to take into account the constraints under which the pathway develops. We shall first consider the evidence for rejecting the classical view, from recent studies on the organization of the retinofugal pathway in adult animals and on the development of that organization. We shall then describe three transformations in the fiber order which all occur in the chiasmatic region, two of which were only recently recognized, and for which we must account.Observations from adult organizationThe difference in the fiber order in the optic nerve and tract

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Herzog, M., T. Otto, and H. Ogmen. "Non-retinotopic perceptual learning." Journal of Vision 11, no. 11 (September 23, 2011): 1022. http://dx.doi.org/10.1167/11.11.1022.

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Boi, M., H. Ogmen, K. Joseph, and M. Herzog. "Non-retinotopic visual search." Journal of Vision 9, no. 8 (March 21, 2010): 1173. http://dx.doi.org/10.1167/9.8.1173.

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Öğmen, Haluk, and Michael H. Herzog. "Information Integration and Information Storage in Retinotopic and Non-Retinotopic Sensory Memory." Vision 5, no. 4 (December 13, 2021): 61. http://dx.doi.org/10.3390/vision5040061.

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The first stage of the Atkinson–Shiffrin model of human memory is a sensory memory (SM). The visual component of the SM was shown to operate within a retinotopic reference frame. However, a retinotopic SM (rSM) is unable to account for vision under natural viewing conditions because, for example, motion information needs to be analyzed across space and time. For this reason, the SM store of the Atkinson–Shiffrin model has been extended to include a non-retinotopic component (nrSM). In this paper, we analyze findings from two experimental paradigms and show drastically different properties of rSM and nrSM. We show that nrSM involves complex processes such as motion-based reference frames and Gestalt grouping, which establish object identities across space and time. We also describe a quantitative model for nrSM and show drastic differences between the spatio-temporal properties of rSM and nrSM. Since the reference-frame of the latter is non-retinotopic and motion-stream based, we suggest that the spatiotemporal properties of the nrSM are in accordance with the spatiotemporal properties of the motion system. Overall, these findings indicate that, unlike the traditional rSM, which is a relatively passive store, nrSM exhibits sophisticated processing properties to manage the complexities of ecological perception.

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Ogmen, H., M. Herzog, and B. Noory. "Dynamic Perception: Synergy between Grouping, Retinotopic Masking, and Non-retinotopic Feature Attribution." Journal of Vision 14, no. 10 (August 22, 2014): 1367. http://dx.doi.org/10.1167/14.10.1367.

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Scharnowski, Frank, Frouke Hermens, Thomas Kammer, Haluk Öğmen, and Michael H. Herzog. "Feature Fusion Reveals Slow and Fast Visual Memories." Journal of Cognitive Neuroscience 19, no. 4 (April 2007): 632–41. http://dx.doi.org/10.1162/jocn.2007.19.4.632.

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Although the visual system can achieve a coarse classification of its inputs in a relatively short time, the synthesis of qualia-rich and detailed percepts can take substantially more time. If these prolonged computations were to take place in a retinotopic space, moving objects would generate extensive smear. However, under normal viewing conditions, moving objects appear relatively sharp and clear, suggesting that a substantial part of visual short-term memory takes place at a nonretinotopic locus. By using a retinotopic feature fusion and a nonretinotopic feature attribution paradigm, we provide evidence for a relatively fast retinotopic buffer and a substantially slower nonretinotopic memory. We present a simple model that can account for the dynamics of these complementary memory processes. Taken together, our results indicate that the visual system can accomplish temporal integration of information while avoiding smear by breaking off sensory memory into fast and slow components that are implemented in retinotopic and nonretinotopic loci, respectively.

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Sabes, Philip N., Boris Breznen, and Richard A. Andersen. "Parietal Representation of Object-Based Saccades." Journal of Neurophysiology 88, no. 4 (October 1, 2002): 1815–29. http://dx.doi.org/10.1152/jn.2002.88.4.1815.

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When monkeys make saccadic eye movements to simple visual targets, neurons in the lateral intraparietal area (LIP) display a retinotopic, or eye-centered, coding of the target location. However natural saccadic eye movements are often directed at objects or parts of objects in the visual scene. In this paper we investigate whether LIP represents saccadic eye movements differently when the target is specified as part of a visually displayed object. Monkeys were trained to perform an object-based saccade task that required them to make saccades to previously cued parts of an abstract object after the object reappeared in a new orientation. We recorded single neurons in area LIP of two macaque monkeys and analyzed their activity in the object-based saccade task, as well as two control tasks: a standard memory saccade task and a fixation task with passive object viewing. The majority of LIP neurons that were tuned in the memory saccade task were also tuned in the object-based saccade task. Using a hierarchical generalized linear model analysis, we compared the effects of three different spatial variables on the firing rate: the retinotopic location of the target, the object-fixed location of the target, and the orientation of the object in space. There was no evidence of an explicit object-fixed representation in the activity in LIP during either of the object-based tasks. In other words, no cells had receptive fields that rotated with the object. While some cells showed a modulation of activity due to the location of the target on the object, these variations were small compared to the retinotopic effects. For most cells, firing rates were best accounted for by either the retinotopic direction of the movement, the orientation of the object, or both spatial variables. The preferred direction of these retinotopic and object orientation effects were found to be invariant across tasks. On average, the object orientation effects were consistent with the retinotopic coding of potential target locations on the object. This interpretation is supported by the fact that the magnitude of these two effects were roughly equal in the early portions of the trial, but around the time of the motor response, the retinotopic effects dominated. We conclude that LIP uses the same retinotopic coding of saccade target whether the target is specified as an absolute point in space or as a location on a moving object.

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Ho, Yi-Ching Lynn, Amandine Cheze, Yih-Yian Sitoh, Esben Thade Petersen, Kong-Yong Goh, Albert Gjedde, and Xavier Golay. "Residual Neurovascular Function and Retinotopy in a Case of Hemianopia." Annals of the Academy of Medicine, Singapore 38, no. 9 (September 15, 2009): 827–31. http://dx.doi.org/10.47102/annals-acadmedsg.v38n9p827.

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Introduction: For occipital cortex strokes resulting in vision disorders, questions about the viability of residual visual cortex remain. Clinical Picture: In a patient with a one-year-old, left, complete, homonymous hemianopia due to a right, posterior cerebral artery, ischaemic infarct, we assessed the visual cortex with fMRI retinotopic mapping prior to starting vision restoration therapy. Outcome: The patient was found to have residual neurovascular function and retinotopic representation in the surviving visual cortex around the infarcted area. Conclusion: The ability to respond to stimuli in part of the blind field, though not consciously perceived, suggests the potential for recovery. Key words: fMRI, Retinotopic mapping, Stroke

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Lauffs, Marc M., Albulena Shaqiri, Andreas Brand, Maya Roinishvili, Eka Chkonia, Haluk Öğmen, and Michael H. Herzog. "Local versus global and retinotopic versus non-retinotopic motion processing in schizophrenia patients." Psychiatry Research 246 (December 2016): 461–65. http://dx.doi.org/10.1016/j.psychres.2016.09.049.

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Matsumiya, Kazumichi. "Retinotopy of Facial Expression Adaptation." Multisensory Research 27, no. 2 (2014): 127–37. http://dx.doi.org/10.1163/22134808-00002446.

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The face aftereffect (FAE; the illusion of faces after adaptation to a face) has been reported to occur without retinal overlap between adaptor and test, but recent studies revealed that the FAE is not constant across all test locations, which suggests that the FAE is also retinotopic. However, it remains unclear whether the characteristic of the retinotopy of the FAE for one facial aspect is the same as that of the FAE for another facial aspect. In the research reported here, an examination of the retinotopy of the FAE for facial expression indicated that the facial expression aftereffect occurs without retinal overlap between adaptor and test, and depends on the retinal distance between them. Furthermore, the results indicate that, although dependence of the FAE on adaptation-test distance is similar between facial expression and facial identity, the FAE for facial identity is larger than that for facial expression when a test face is presented in the opposite hemifield. On the basis of these results, I discuss adaptation mechanisms underlying facial expression processing and facial identity processing for the retinotopy of the FAE.

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Katyal, Sucharit, Samir Zughni, Clint Greene, and David Ress. "Topography of Covert Visual Attention in Human Superior Colliculus." Journal of Neurophysiology 104, no. 6 (December 2010): 3074–83. http://dx.doi.org/10.1152/jn.00283.2010.

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Experiments were performed to examine the topography of covert visual attention signals in human superior colliculus (SC), both across its surface and in its depth. We measured the retinotopic organization of SC to direct visual stimulation using a 90° wedge of moving dots that slowly rotated around fixation. Subjects ( n = 5) were cued to perform a difficult speed-discrimination task in the rotating region. To measure the retinotopy of covert attention, we used a full-field array of similarly moving dots. Subjects were cued to perform the same speed-discrimination task within a 90° wedge-shaped region, and only the cue rotated around fixation. High-resolution functional magnetic resonance imaging (fMRI, 1.2 mm voxels) data were acquired throughout SC. These data were then aligned to a high-resolution T1-weighted reference volume. The SC was segmented in this volume so that the surface of the SC could be computationally modeled and to permit calculation of a depth map for laminar analysis. Retinotopic maps were obtained for both direct visual stimulation and covert attention. These maps showed a similar spatial distribution to visual stimulation maps observed in rhesus macaque and were in registration with each other. Within the depth of SC, both visual attention and stimulation produced activity primarily in the superficial and intermediate layers, but stimulation activity extended significantly more deeply than attention.

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Vaina, Lucia M., Sergei Soloviev, Finnegan J. Calabro, Ferdinando Buonanno, Richard Passingham, and Alan Cowey. "Reorganization of Retinotopic Maps after Occipital Lobe Infarction." Journal of Cognitive Neuroscience 26, no. 6 (June 2014): 1266–82. http://dx.doi.org/10.1162/jocn_a_00538.

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We studied patient JS, who had a right occipital infarct that encroached on visual areas V1, V2v, and VP. When tested psychophysically, he was very impaired at detecting the direction of motion in random dot displays where a variable proportion of dots moving in one direction (signal) were embedded in masking motion noise (noise dots). The impairment on this motion coherence task was especially marked when the display was presented to the upper left (affected) visual quadrant, contralateral to his lesion. However, with extensive training, by 11 months his threshold fell to the level of healthy participants. Training on the motion coherence task generalized to another motion task, the motion discontinuity task, on which he had to detect the presence of an edge that was defined by the difference in the direction of the coherently moving dots (signal) within the display. He was much better at this task at 8 than 3 months, and this improvement was associated with an increase in the activation of the human MT complex (hMT+) and in the kinetic occipital region as shown by repeated fMRI scans. We also used fMRI to perform retinotopic mapping at 3, 8, and 11 months after the infarct. We quantified the retinotopy and areal shifts by measuring the distances between the center of mass of functionally defined areas, computed in spherical surface-based coordinates. The functionally defined retinotopic areas V1, V2v, V2d, and VP were initially smaller in the lesioned right hemisphere, but they increased in size between 3 and 11 months. This change was not found in the normal, left hemisphere of the patient or in either hemispheres of the healthy control participants. We were interested in whether practice on the motion coherence task promoted the changes in the retinotopic maps. We compared the results for patient JS with those from another patient (PF) who had a comparable lesion but had not been given such practice. We found similar changes in the maps in the lesioned hemisphere of PF. However, PF was only scanned at 3 and 7 months, and the biggest shifts in patient JS were found between 8 and 11 months. Thus, it is important to carry out a prospective study with a trained and untrained group so as to determine whether the patterns of reorganization that we have observed can be further promoted by training.

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Kaido, Takanobu, Tohru Hoshida, Toshiaki Taoka, and Toshisuke Sakaki. "Retinotopy with coordinates of lateral occipital cortex in humans." Journal of Neurosurgery 101, no. 1 (July 2004): 114–18. http://dx.doi.org/10.3171/jns.2004.101.1.0114.

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Object. The lateral occipital cortex in humans is known as the “extrastriate visual cortex.” It is, however, an unexplored field of research, and the anatomical nomenclature for its surface has still not been standardized. This study was designed to investigate whether the lateral occipital cortex in humans has retinotopic representation. Methods. Four right-handed patients with a diagnosis of intractable epilepsy from space-occupying lesions in the occipital lobe or epilepsy originating in the occipital lobe received permanently implanted subdural electrodes. Electrical cortical stimulation was applied directly applied to the brain through metal electrodes by using a biphasic stimulator. The location of each electrode was measured on a lateral skull x-ray study. Each patient considered a whiteboard with vertical and horizontal median lines. The patient was asked to look at the midpoint on the whiteboard. If a visual hallucination or illusion occurred, the patient recorded its outline, shape, color, location, and motion on white paper one tenth the size of, and with vertical and horizontal median lines similar to those on, the whiteboard. Polar angles and eccentricities of the midpoints of the phosphenes from the coordinate origin were measured on the paper. On stimulation of the lateral occipital lobe, 44 phosphenes occurred. All phosphenes were circular or dotted, with a diameter of approximately 1 cm, except one that was like a curtain in the peripheral end of the upper and lower visual fields on stimulation of the parietooccipital region. All phosphenes appeared in the visual field contralateral to the cerebral hemisphere stimulated. On stimulation of the lateral occipital lobe, 22 phosphenes moved centrifugally or toward a horizontal line. From three-dimensional scatterplots and contour maps of the polar angles and eccentricities in relation to the x-ray coordinates of the electrodes, one can infer that the lateral occipital cortex in humans has retinotopic representation. Conclusions. The authors found that phosphenes induced by electrical cortical stimulation of the lateral occipital cortex represent retinotopy. From these results one can assert that visual field representation with retinotopic relation exists in the extrastriate visual cortex.

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Chouinard, Philippe A., Christopher L. Striemer, Won Hyung A. Ryu, Irene Sperandio, Melvyn A. Goodale, David A. Nicolle, Brian Rotenberg, and Neil Duggal. "Retinotopic organization of the visual cortex before and after decompression of the optic chiasm in a patient with pituitary macroadenoma." Journal of Neurosurgery 117, no. 2 (August 2012): 218–24. http://dx.doi.org/10.3171/2012.4.jns112158.

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Compression induced by a pituitary tumor on the optic chiasm can generate visual field deficits, yet it is unknown how this compression affects the retinotopic organization of the visual cortex. It is also not known how the effect of the tumor on the retinotopic organization of the visual cortex changes after decompression. The authors used functional MRI (fMRI) to map the retinotopic organization of the visual cortex in a 68-year-old right-handed woman before and 3 months after surgery for a recurrent pituitary macroadenoma. The authors demonstrated that longitudinal changes in visual field perimetry, as assessed by the automated Humphrey visual field test, correlated with longitudinal changes in fMRI activation in a retinotopic manner. In other words, after decompression of the optic chiasm, fMRI charted the recruitment of the visual cortex in a way that matched gains in visual field perimetry. On the basis of this case, the authors propose that fMRI can chart neural plasticity of the visual cortex on an individual basis and that it can also serve as a complementary tool in decision making with respect to management of patients with chiasmal compression.

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Winawer, Jonathan, and Nathan Witthoft. "Identification of the ventral occipital visual field maps in the human brain." F1000Research 6 (August 21, 2017): 1526. http://dx.doi.org/10.12688/f1000research.12364.1.

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The location and topography of the first three visual field maps in the human brain, V1-V3, are well agreed upon and routinely measured across most laboratories. The position of 4th visual field map, ‘hV4’, is identified with less consistency in the neuroimaging literature. Using magnetic resonance imaging data, we describe landmarks to help identify the position and borders of ‘hV4’. The data consist of anatomical images, visualized as cortical meshes to highlight the sulcal and gyral patterns, and functional data obtained from retinotopic mapping experiments, visualized as eccentricity and angle maps on the cortical surface. Several features of the functional and anatomical data can be found across nearly all subjects and are helpful for identifying the location and extent of the hV4 map. The medial border of hV4 is shared with the posterior, ventral portion of V3, and is marked by a retinotopic representation of the upper vertical meridian. The anterior border of hV4 is shared with the VO-1 map, and falls on a retinotopic representation of the peripheral visual field, usually coincident with the posterior transverse collateral sulcus. The ventro-lateral edge of the map typically falls on the inferior occipital gyrus, where functional MRI artifacts often obscure the retinotopic data. Finally, we demonstrate the continuity of retinotopic parameters between hV4 and its neighbors; hV4 and V3v contain iso-eccentricity lines in register, whereas hV4 and VO-1 contain iso-polar angle lines in register. Together, the multiple constraints allow for a consistent identification of the hV4 map across most human subjects.

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Tu, Yanshuai, Duyan Ta, Zhong-Lin Lu, and Yalin Wang. "Topological Smoothing of Retinotopic Maps." Journal of Vision 21, no. 9 (September 27, 2021): 2464. http://dx.doi.org/10.1167/jov.21.9.2464.

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Mansouri, Behzad, Bruce C. Hansen, and Robert F. Hess. "Disrupted Retinotopic Maps in Amblyopia." Investigative Opthalmology & Visual Science 50, no. 7 (July 1, 2009): 3218. http://dx.doi.org/10.1167/iovs.08-2914.

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Corbett, J., and M. Carrasco. "Visual performance fields are retinotopic." Journal of Vision 8, no. 6 (March 29, 2010): 746. http://dx.doi.org/10.1167/8.6.746.

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Seidel, Dirk, Lyle S. Gray, and Gordon Heron. "Retinotopic Accommodation Responses in Myopia." Investigative Opthalmology & Visual Science 44, no. 3 (March 1, 2003): 1035. http://dx.doi.org/10.1167/iovs.02-0264.

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Shim, Won Mok, Yuhong V. Jiang, and Nancy Kanwisher. "Redundancy gains in retinotopic cortex." Journal of Neurophysiology 110, no. 9 (November 1, 2013): 2227–35. http://dx.doi.org/10.1152/jn.00175.2013.

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It is widely claimed that interactions among simultaneously presented visual stimuli are suppressive and that these interactions primarily occur when stimuli fall within the same receptive field ( Desimone and Duncan 1995 ). Here, we show evidence for a novel form of interaction between simultaneously presented but distant stimuli that does not fit either pattern. To examine interactions between simultaneously presented stimuli, we measure the response to a single stimulus as a function of whether or not other stimuli are also presented simultaneously, and we further ask how the response to a given stimulus is affected by whether the simultaneously present stimuli are identical or different from each other. Our method reveals a new phenomenon of “redundancy gain:” the visual response to a stimulus is higher when accompanied by identical stimuli than when that stimulus is presented alone, even though the stimuli are displayed in separate visual quadrants. This pattern is observed throughout the visual hierarchy, including V1 and V2, and we show that it is distinct from the well-known simultaneous suppression effect (Kastner et al. 1998). We propose that the redundancy gain in early retinotopic cortex results from feedback from higher visual areas and may underlie perceptual averaging and other ensemble coding phenomena observed behaviorally.

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Cang, Jianhua. "Functional Development of Retinotopic Maps." Neuroscience Research 65 (January 2009): S10. http://dx.doi.org/10.1016/j.neures.2009.09.1529.

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van Boxtel, Jeroen J. A., David Alais, and Raymond van Ee. "Retinotopic and non-retinotopic stimulus encoding in binocular rivalry and the involvement of feedback." Journal of Vision 8, no. 5 (May 30, 2008): 17. http://dx.doi.org/10.1167/8.5.17.

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Kumar, Mari Ganesh, Ming Hu, Aadhirai Ramanujan, Mriganka Sur, and Hema A. Murthy. "Functional parcellation of mouse visual cortex using statistical techniques reveals response-dependent clustering of cortical processing areas." PLOS Computational Biology 17, no. 2 (February 4, 2021): e1008548. http://dx.doi.org/10.1371/journal.pcbi.1008548.

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The visual cortex of the mouse brain can be divided into ten or more areas that each contain complete or partial retinotopic maps of the contralateral visual field. It is generally assumed that these areas represent discrete processing regions. In contrast to the conventional input-output characterizations of neuronal responses to standard visual stimuli, here we asked whether six of the core visual areas have responses that are functionally distinct from each other for a given visual stimulus set, by applying machine learning techniques to distinguish the areas based on their activity patterns. Visual areas defined by retinotopic mapping were examined using supervised classifiers applied to responses elicited by a range of stimuli. Using two distinct datasets obtained using wide-field and two-photon imaging, we show that the area labels predicted by the classifiers were highly consistent with the labels obtained using retinotopy. Furthermore, the classifiers were able to model the boundaries of visual areas using resting state cortical responses obtained without any overt stimulus, in both datasets. With the wide-field dataset, clustering neuronal responses using a constrained semi-supervised classifier showed graceful degradation of accuracy. The results suggest that responses from visual cortical areas can be classified effectively using data-driven models. These responses likely reflect unique circuits within each area that give rise to activity with stronger intra-areal than inter-areal correlations, and their responses to controlled visual stimuli across trials drive higher areal classification accuracy than resting state responses.

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Murray, Scott O., Cheryl A. Olman, and Daniel Kersten. "Spatially Specific fMRI Repetition Effects in Human Visual Cortex." Journal of Neurophysiology 95, no. 4 (April 2006): 2439–45. http://dx.doi.org/10.1152/jn.01236.2005.

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The functional MRI (fMRI) response to a pair of identical, successively presented stimuli can result in a smaller signal than the presentation of two nonidentical stimuli. This “repetition effect” has become a frequently used tool to make inferences about neural selectivity in specific cortical areas. However, little is known about the mechanism(s) underlying the effect. In particular, despite many successful applications of the technique in higher visual areas, repetition effects in lower visual areas [e.g., primary visual cortex (V1)] have been more difficult to characterize. One property that is well understood in early visual areas is the mapping of visual field locations to specific areas of the cortex (i.e., retinotopy). We used the retinotopic organization of V1 to activate progressively different populations of neurons in a rapid fMRI experimental design. We observed a repetition effect (reduced signal) when localized stimulus elements were repeated in identical locations. We show that this effect is spatially tuned and largely independent of both interstimulus interval (100–800 ms) and the focus of attention. Using the same timing parameters for which we observed a large effect of spatial position, we also examined the response to orientation changes and observed no effect of an orientation change on the response to repeated stimuli in V1 but significant effects in other retinotopic areas. Given these results, we discuss the possible causes of these repetition effects as well as the implications for interpreting other experiments that use this potentially powerful imaging technique.

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Harris, Laurence R., and Lori A. Lott. "Sensitivity to full-field visual movement compatible with head rotation: Variations with eye-in-head position." Visual Neuroscience 13, no. 2 (March 1996): 277–82. http://dx.doi.org/10.1017/s0952523800007513.

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AbstractVariations in velocity detection thresholds for full-field visual rotation about various axes are compatible with a simple channel-based system for coding the axis and velocity of the rotation (Harris & Lott, 1995). The present paper looks at the frame of reference for this system. The head-centered, craniotopic reference system and the retinal-based, retinotopic reference systems were separated by using eccentric eye positions. We measured the threshold for detecting full-field visual rotation about a selection of axes in the sagittal plane with the eyes held either 22½ degs up, straight ahead or 22½ degs down in the head. The characteristic features of the variation in detection thresholds did not stay stable in craniotopic coordinates but moved with the eyes and were constant in retinotopic coordinates. This suggests that the coding of head rotation by the visual system is in retinotopic coordinates.

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Bo, Ke, Siyang Yin, Yuelu Liu, Zhenhong Hu, Sreenivasan Meyyappan, Sungkean Kim, Andreas Keil, and Mingzhou Ding. "Decoding Neural Representations of Affective Scenes in Retinotopic Visual Cortex." Cerebral Cortex 31, no. 6 (February 16, 2021): 3047–63. http://dx.doi.org/10.1093/cercor/bhaa411.

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Abstract The perception of opportunities and threats in complex visual scenes represents one of the main functions of the human visual system. The underlying neurophysiology is often studied by having observers view pictures varying in affective content. It has been shown that viewing emotionally engaging, compared with neutral, pictures (1) heightens blood flow in limbic, frontoparietal, and anterior visual structures and (2) enhances the late positive event-related potential (LPP). The role of retinotopic visual cortex in this process has, however, been contentious, with competing theories predicting the presence versus absence of emotion-specific signals in retinotopic visual areas. Recording simultaneous electroencephalography–functional magnetic resonance imaging while observers viewed pleasant, unpleasant, and neutral affective pictures, and applying multivariate pattern analysis, we found that (1) unpleasant versus neutral and pleasant versus neutral decoding accuracy were well above chance level in retinotopic visual areas, (2) decoding accuracy in ventral visual cortex (VVC), but not in early or dorsal visual cortex, was correlated with LPP, and (3) effective connectivity from amygdala to VVC predicted unpleasant versus neutral decoding accuracy, whereas effective connectivity from ventral frontal cortex to VVC predicted pleasant versus neutral decoding accuracy. These results suggest that affective scenes evoke valence-specific neural representations in retinotopic visual cortex and that these representations are influenced by reentry signals from anterior brain regions.

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Talsma, Durk, Brian J. White, Sebastiaan Mathôt, Douglas P. Munoz, and Jan Theeuwes. "A Retinotopic Attentional Trace after Saccadic Eye Movements: Evidence from Event-related Potentials." Journal of Cognitive Neuroscience 25, no. 9 (September 2013): 1563–77. http://dx.doi.org/10.1162/jocn_a_00390.

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Saccadic eye movements are a major source of disruption to visual stability, yet we experience little of this disruption. We can keep track of the same object across multiple saccades. It is generally assumed that visual stability is due to the process of remapping, in which retinotopically organized maps are updated to compensate for the retinal shifts caused by eye movements. Recent behavioral and ERP evidence suggests that visual attention is also remapped, but that it may still leave a residual retinotopic trace immediately after a saccade. The current study was designed to further examine electrophysiological evidence for such a retinotopic trace by recording ERPs elicited by stimuli that were presented immediately after a saccade (80 msec SOA). Participants were required to maintain attention at a specific location (and to memorize this location) while making a saccadic eye movement. Immediately after the saccade, a visual stimulus was briefly presented at either the attended location (the same spatiotopic location), a location that matched the attended location retinotopically (the same retinotopic location), or one of two control locations. ERP data revealed an enhanced P1 amplitude for the stimulus presented at the retinotopically matched location, but a significant attenuation for probes presented at the original attended location. These results are consistent with the hypothesis that visuospatial attention lingers in retinotopic coordinates immediately following gaze shifts.

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McIlwain, James T. "Topography of eye-position sensitivity of saccades evoked electrically from the cat's superior colliculus." Visual Neuroscience 4, no. 3 (March 1990): 289–98. http://dx.doi.org/10.1017/s0952523800003412.

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AbstractSaccades evoked electrically from the deep layers of the superior colliculus have been examined in the alert cat with its head fixed. Amplitudes of the vertical and horizontal components varied linearly with the starting position of the eye. The slopes of the linear-regression lines provided an estimate of the sensitivity of these components to initial eye position. In observations on 29 sites in nine cats, the vertical and horizontal components of saccades evoked from a given site were rarely influenced to the same degree by initial eye position. For most sites, the horizontal component was more sensitive than the vertical component. Sensitivities of vertical and horizontal components were lowest near the representations of the horizontal and vertical meridians, respectively, of the collicular retinotopic map, but otherwise exhibited no systematic retinotopic dependence. Estimates of component amplitudes for saccades evoked from the center of the oculomotor range also diverged significantly from those predicted from the retinotopic map. The results of this and previous studies indicate that electrical stimulation of the cat's superior colliculus cannot yield a unique oculomotor map or one that is in register everywhere with the sensory retinotopic map. Several features of these observations suggest that electrical stimulation of the colliculus produces faulty activation of a saccadic control system that computes target position with respect to the head and that small and large saccades are controlled differently.

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Otaki, Sho, Sota Watanabe, and Kazuo Fujita. "Differential motion processing between species facing Ternus–Pikler display: Non-retinotopic humans versus retinotopic pigeons." Vision Research 103 (October 2014): 32–40. http://dx.doi.org/10.1016/j.visres.2014.08.007.

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Chen, He, and Yuji Naya. "Automatic Encoding of a View-Centered Background Image in the Macaque Temporal Lobe." Cerebral Cortex 30, no. 12 (July 8, 2020): 6270–83. http://dx.doi.org/10.1093/cercor/bhaa183.

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Abstract Perceptual processing along the ventral visual pathway to the hippocampus (HPC) is hypothesized to be substantiated by signal transformation from retinotopic space to relational space, which represents interrelations among constituent visual elements. However, our visual perception necessarily reflects the first person’s perspective based on the retinotopic space. To investigate this two-facedness of visual perception, we compared neural activities in the temporal lobe (anterior inferotemporal cortex, perirhinal and parahippocampal cortices, and HPC) between when monkeys gazed on an object and when they fixated on the screen center with an object in their peripheral vision. We found that in addition to the spatially invariant object signal, the temporal lobe areas automatically represent a large-scale background image, which specify the subject’s viewing location. These results suggest that a combination of two distinct visual signals on relational space and retinotopic space may provide the first person’s perspective serving for perception and presumably subsequent episodic memory.

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Maeda, Kiyohiro, Hiroki Yamamoto, Masaki Fukunaga, Masahiro Umeda, Chuzo Tanaka, and Yoshimichi Ejima. "Neural Correlates of Color-Selective Metacontrast in Human Early Retinotopic Areas." Journal of Neurophysiology 104, no. 4 (October 2010): 2291–301. http://dx.doi.org/10.1152/jn.00923.2009.

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Metacontrast is a visual illusion in which the visibility of a target stimulus is virtually lost when immediately followed by a nonoverlapping mask stimulus. For a colored target, metacontrast is color-selective, with target visibility markedly reduced when the mask and target are the same color, but only slightly reduced when the colors differ. This study investigated neural correlates of color-selective metacontrast for cone-opponent red and green stimuli in the human V1, V2, and V3 using functional magnetic resonance imaging. Neural activity was suppressed when the target was rendered less visible by the same-colored mask, and the suppression was localized in the cortical region retinotopically representing the target, correlating with the perceptual topography of visibility/invisibility rather than the physical topography of the stimulus. Retinotopy-based group analysis found that activity suppression was statistically significant for V2 and V3 and that its localization to the target region was statistically significant for V2. These results suggest that retinotopic color representations in early visual areas, especially in V2, are closely linked to the visibility of color.

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Zhang, E., and W. Li. "Perceptual learning beyond retinotopic reference frame." Proceedings of the National Academy of Sciences 107, no. 36 (August 23, 2010): 15969–74. http://dx.doi.org/10.1073/pnas.1003547107.

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Collins, Therese. "Retinotopic serial dependency in visual perception." Journal of Vision 19, no. 10 (September 6, 2019): 196d. http://dx.doi.org/10.1167/19.10.196d.

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Mansouri, B., and R. Hess. "A disrupted retinotopic map in amblyopia." Journal of Vision 6, no. 6 (March 19, 2010): 543. http://dx.doi.org/10.1167/6.6.543.

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Conner, I. P., T. L. Schwartz, J. V. Odom, and J. D. Mendola. "Monocular retinotopic mapping in amblyopic adults." Journal of Vision 3, no. 9 (March 16, 2010): 112. http://dx.doi.org/10.1167/3.9.112.

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Parwaga, Sandeep, David Buckley, and Philip A. Duke. "Tilt representation beyond the retinotopic level." Journal of Vision 16, no. 3 (February 11, 2016): 11. http://dx.doi.org/10.1167/16.3.11.

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Wenderoth, Peter, and Mark Wiese. "Retinotopic encoding of the direction aftereffect." Vision Research 48, no. 19 (September 2008): 1949–54. http://dx.doi.org/10.1016/j.visres.2008.06.013.

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Bruno, A., I. Ayhan, and A. Johnston. "Retinotopic adaptation-based visual duration compression." Journal of Vision 10, no. 10 (August 31, 2010): 30. http://dx.doi.org/10.1167/10.10.30.

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Journal articles on the topic 'Retinotopic'

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