23 results on '"RETINOTOPIC ORGANIZATION"'
Search Results
2. Ultra-high field neuroimaging reveals fine-scale processing for 3D perception
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Elisa Zamboni, Andrew E. Welchman, Valentin G. Kemper, Ke Jia, Nuno Reis Goncalves, Adrian K. T. Ng, Rainer Goebel, Zoe Kourtzi, Ng, Adrian KT [0000-0003-2820-5270], Zamboni, Elisa [0000-0001-9200-8031], Welchman, Andrew E [0000-0002-7559-3299], Kourtzi, Zoe [0000-0001-9441-7832], Apollo - University of Cambridge Repository, Vision, and RS: FPN CN 1
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Adult ,Male ,7 TESLA ,genetic structures ,media_common.quotation_subject ,Stereoscopy ,Neuroimaging ,Article ,law.invention ,ultra-high-field fMRI ,Young Adult ,GE BOLD ,RETINOTOPIC ORGANIZATION ,law ,Perception ,medicine ,LAMINAR DIFFERENCES ,Humans ,visual cortex ,VISUAL-CORTEX ,media_common ,depth perception ,General Neuroscience ,BINOCULAR DISPARITY ,functional connectivity ,CORTICAL DEPTH ,Magnetic Resonance Imaging ,Functional imaging ,Visual cortex ,medicine.anatomical_structure ,ANALYSIS STRATEGIES ,Random dot stereogram ,FMRI ,Binocular disparity ,Female ,Depth perception ,Psychology ,Neuroscience ,Binocular vision ,Photic Stimulation ,RESPONSES - Abstract
Binocular disparity provides critical information about three-dimensional (3D) structures to support perception and action. In the past decade significant progress has been made in uncovering human brain areas engaged in the processing of binocular disparity signals. Yet, the fine-scale brain processing underlying 3D perception remains unknown. Here, we use ultra-high-field (7T) functional imaging at submillimeter resolution to examine fine-scale BOLD fMRI signals involved in 3D perception. In particular, we sought to interrogate the local circuitry involved in disparity processing by sampling fMRI responses at different positions relative to the cortical surface (i.e., across cortical depths corresponding to layers). We tested for representations related to 3D perception by presenting participants (male and female, N = 8) with stimuli that enable stable stereoscopic perception [i.e., correlated random dot stereograms (RDS)] versus those that do not (i.e., anticorrelated RDS). Using multivoxel pattern analysis (MVPA), we demonstrate cortical depth-specific representations in areas V3A and V7 as indicated by stronger pattern responses for correlated than for anticorrelated stimuli in upper rather than deeper layers. Examining informational connectivity, we find higher feedforward layer-to-layer connectivity for correlated than anticorrelated stimuli between V3A and V7. Further, we observe disparity-specific feedback from V3A to V1 and from V7 to V3A. Our findings provide evidence for the role of V3A as a key nexus for disparity processing, which is implicated in feedforward and feedback signals related to the perceptual estimation of 3D structures. SIGNIFICANCE STATEMENT Binocular vision plays a significant role in supporting our interactions with the surrounding environment. The fine-scale neural mechanisms that underlie the brain9s skill in extracting 3D structures from binocular signals are poorly understood. Here, we capitalize on recent advances in ultra-high-field functional imaging to interrogate human brain circuits involved in 3D perception at submillimeter resolution. We provide evidence for the role of area V3A as a key nexus for disparity processing, which is implicated in feedforward and feedback signals related to the perceptual estimation of 3D structures from binocular signals. These fine-scale measurements help bridge the gap between animal neurophysiology and human fMRI studies investigating cross-scale circuits, from micro circuits to global brain networks for 3D perception.
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- 2021
3. A Probabilistic Functional Atlas of Human Occipito-Temporal Visual Cortex
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Rainer Goebel, Rick van Hoof, Job van den Hurk, Mona Rosenke, Kalanit Grill-Spector, Vision, RS: FPN CN 1, Language, RS: FPN CN 7, and RS: FPN Studio Europa Maastricht
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Male ,Computer science ,computer.software_genre ,Visual processing ,0302 clinical medicine ,Voxel ,Cortex (anatomy) ,MAPS ,BODY ,visual cortex ,BRAIN ,Temporal cortex ,Brain Mapping ,medicine.diagnostic_test ,AcademicSubjects/SCI01870 ,05 social sciences ,Cognitive neuroscience of visual object recognition ,Magnetic Resonance Imaging ,Temporal Lobe ,medicine.anatomical_structure ,WORD FORM AREA ,Pattern Recognition, Visual ,FMRI ,Visual Perception ,Original Article ,Female ,Occipital Lobe ,Cartography ,Adult ,Cognitive Neuroscience ,cortex-based alignment ,SELECTIVE REGIONS ,050105 experimental psychology ,object recognition ,Cellular and Molecular Neuroscience ,03 medical and health sciences ,RETINOTOPIC ORGANIZATION ,Atlas (anatomy) ,Region of interest ,medicine ,Humans ,retinotopy ,LOCATION ,Visual Pathways ,0501 psychology and cognitive sciences ,FUSIFORM FACE AREA ,PERCEPTION ,Probabilistic logic ,Fusiform face area ,Cortex (botany) ,Visual cortex ,Retinotopy ,human brain atlas ,Functional magnetic resonance imaging ,computer ,030217 neurology & neurosurgery - Abstract
Human visual cortex contains many retinotopic and category-specific regions. These brain regions have been the focus of a large body of functional magnetic resonance imaging research, significantly expanding our understanding of visual processing. As studying these regions requires accurate localization of their cortical location, researchers perform functional localizer scans to identify these regions in each individual. However, it is not always possible to conduct these localizer scans. Here, we developed and validated a functional region of interest (ROI) atlas of early visual and category-selective regions in human ventral and lateral occipito-temporal cortex. Results show that for the majority of functionally defined ROIs, cortex-based alignment results in lower between-subject variability compared to nonlinear volumetric alignment. Furthermore, we demonstrate that 1) the atlas accurately predicts the location of an independent dataset of ventral temporal cortex ROIs and other atlases of place selectivity, motion selectivity, and retinotopy. Next, 2) we show that the majority of voxel within our atlas is responding mostly to the labeled category in a left-out subject cross-validation, demonstrating the utility of this atlas. The functional atlas is publicly available (download.brainvoyager.com/data/visfAtlas.zip) and can help identify the location of these regions in healthy subjects as well as populations (e.g., blind people, infants) in which functional localizers cannot be run.
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- 2021
4. Vergence eye movement and lens accommodation: cortical processing and neuronal pathway
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Bando, T., Hara, N., Takagi, M., Hasebe, H., Takada, R., Toda, H., Franzén, Ove, editor, Richter, Hans, editor, and Stark, Lawrence, editor
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- 2000
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5. Population receptive fields in non-human primates from whole-brain fmri and large-scale neurophysiology in visual cortex
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Xing Chen, Pieter R. Roelfsema, Peter Christiaan Klink, Vim Vanduffel, Integrative Neurophysiology, Amsterdam Neuroscience - Cellular & Molecular Mechanisms, Adult Psychiatry, and Amsterdam Neuroscience - Systems & Network Neuroscience
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Life Sciences & Biomedicine - Other Topics ,MONKEY CAUDATE NEURONS ,MACAQUE MONKEY ,Male ,genetic structures ,Computer science ,non-human primate ,Local field potential ,Signal ,0302 clinical medicine ,Rhesus macaque ,Primate ,Magnetic Resonance ,Biology (General) ,SPATIAL SUMMATION ,Default mode network ,Visual Cortex ,Neurons ,Brain Mapping ,0303 health sciences ,education.field_of_study ,neuroimaging ,biology ,General Neuroscience ,Brain ,Electroencephalography ,General Medicine ,Human brain ,Magnetic Resonance Imaging ,HEMODYNAMIC SIGNALS ,medicine.anatomical_structure ,population receptive field ,VENTRAL EXTRASTRIATE CORTEX ,Medicine ,Insight ,Life Sciences & Biomedicine ,vision ,QH301-705.5 ,Science ,Population ,nonhuman primate ,FUNCTIONAL-PROPERTIES ,VISUOTOPIC ORGANIZATION ,Summation ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,RETINOTOPIC ORGANIZATION ,Neuroimaging ,biology.animal ,medicine ,Animals ,education ,Biology ,TOPOGRAPHIC ORGANIZATION ,030304 developmental biology ,Science & Technology ,General Immunology and Microbiology ,Neurophysiology ,Macaca mulatta ,Oxygen ,Visual cortex ,nervous system ,Regional Blood Flow ,Receptive field ,LATERAL GENICULATE-NUCLEUS ,neurophysiology ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Population receptive field (pRF) modeling is a popular fMRI method to map the retinotopic organization of the human brain. While fMRI-based pRF maps are qualitatively similar to invasively recorded single-cell receptive fields in animals, it remains unclear what neuronal signal they represent. We addressed this question in awake nonhuman primates comparing whole-brain fMRI and large-scale neurophysiological recordings in areas V1 and V4 of the visual cortex. We examined the fits of several pRF models based on the fMRI blood-oxygen-level-dependent (BOLD) signal, multi-unit spiking activity (MUA), and local field potential (LFP) power in different frequency bands. We found that pRFs derived from BOLD-fMRI were most similar to MUA-pRFs in V1 and V4, while pRFs based on LFP gamma power also gave a good approximation. fMRI-based pRFs thus reliably reflect neuronal receptive field properties in the primate brain. In addition to our results in V1 and V4, the whole-brain fMRI measurements revealed retinotopic tuning in many other cortical and subcortical areas with a consistent increase in pRF size with increasing eccentricity, as well as a retinotopically specific deactivation of default mode network nodes similar to previous observations in humans. ispartof: ELIFE vol:10 ispartof: location:England status: published
- Published
- 2021
6. High-gamma oscillations precede visual steady-state responses: A human electrocorticography study
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Paul Boon, Dirk Van Roost, Marc M. Van Hulle, Evelien Carrette, Alfred Meurs, Benjamin Wittevrongel, and Elvira Khachatryan
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Drug Resistant Epilepsy ,Computer science ,photic driving ,tagging ,Electroencephalography ,0302 clinical medicine ,SIGNALS ,Medicine and Health Sciences ,Gamma Rhythm ,EEG ,Cortical Synchronization ,phase-amplitude coupling (PAC) ,Electrocorticography ,Research Articles ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,LATENCY ,05 social sciences ,frequency tagging ,Human brain ,HUMAN BRAIN ,medicine.anatomical_structure ,Neurology ,frequency ,Visual Perception ,Anatomy ,phase locking ,Research Article ,CORTEX ,Steady state (electronics) ,EVOKED-RESPONSE ,electrocorticography (ECoG) ,phase‐amplitude coupling (PAC) ,Fixation, Ocular ,Lateral geniculate nucleus ,050105 experimental psychology ,03 medical and health sciences ,RETINOTOPIC ORGANIZATION ,medicine ,Humans ,0501 psychology and cognitive sciences ,Radiology, Nuclear Medicine and imaging ,Latency (engineering) ,SSVEP ,cross‐frequency coupling (CFC) ,FEEDBACK ,Mechanism (biology) ,Flicker ,ATTENTION ,cross-frequency coupling (CFC) ,Neurology (clinical) ,LATERAL GENICULATE-NUCLEUS ,Neuroscience ,030217 neurology & neurosurgery ,Photic Stimulation - Abstract
The robust steady‐state cortical activation elicited by flickering visual stimulation has been exploited by a wide range of scientific studies. As the fundamental neural response inherits the spectral properties of the gazed flickering, the paradigm has been used to chart cortical characteristics and their relation to pathologies. However, despite its widespread adoption, the underlying neural mechanisms are not well understood. Here, we show that the fundamental response is preceded by high‐gamma (55–125 Hz) oscillations which are also synchronised to the gazed frequency. Using a subdural recording of the primary and associative visual cortices of one human subject, we demonstrate that the latencies of the high‐gamma and fundamental components are highly correlated on a single‐trial basis albeit that the latter is consistently delayed by approximately 55 ms. These results corroborate previous reports that top‐down feedback projections are involved in the generation of the fundamental response, but, in addition, we show that trial‐to‐trial variability in fundamental latency is paralleled by a highly similar variability in high‐gamma latency. Pathology‐ or paradigm‐induced alterations in steady‐state responses could thus originate either from deviating visual gamma responses or from aberrations in the neural feedback mechanism. Experiments designed to tease apart the two processes are expected to provide deeper insights into the studied paradigm., The robust steady‐state cortical activation elicited by flickering visual stimulation has been exploited by a wide range of neuroscientific and clinical studies, but the neural mechanisms behind its generation are not well understood. In this manuscript, we show that the fundamental response is preceded by high‐gamma (55–125 Hz) oscillations which are also synchronised to the gazed frequency. Using a subdural recording of the primary and associative visual cortices of one human subject, we demonstrate that both latencies of the gamma and fundamental components are highly correlated on a single‐trial basis albeit that the latter is consistently delayed by approximately 55 ms.
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- 2020
7. Spatial distance between target and irrelevant patch modulates detection in a texture segmentation task.
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SCHADE, URSULA and MEINECKE, CRISTINA
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SPACE perception , *GEOGRAPHICAL perception , *DEPTH perception , *DISTANCES , *MATERIALS texture - Abstract
In three texture segmentation experiments a target patch had to be detected. We studied the impact of a task-irrelevant patch in the backward mask on detection performance, and especially the modulating effects of its spatial distance to the target. It was assumed that the signals of the two texture irregularities interact as a function of their spatial distance. Experiment 1 revealed that the task-irrelevant patch impaired target detection only when the distance was small. In Experiments 2 and 3 with systematically varying distances, detection performance increased linearly with distance until a maximum point. If the task-irrelevant patch appeared outside of a critical distance, performance did not increase further with increasing distance. Our findings are discussed in terms of the biased competition account. It is proposed that the critical distance may correspond to the average receptive field size of a cortical area that is critical for target detection. [ABSTRACT FROM AUTHOR]
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- 2009
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8. Emergence and transmission of visual awareness through optical coding in the brain: A redox molecular hypothesis on visual mental imagery.
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Bókkon, István and D’Angiulli, Amedeo
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VISUAL cortex ,MENTAL imagery ,NEURAL transmission ,BIOLUMINESCENCE ,CELLULAR signal transduction ,CYTOCHROME oxidase ,TRANSCRANIAL magnetic stimulation - Abstract
Abstract: Does the primary visual cortex mediate consciousness for higher-level stages of information processing by providing an outlet for mental imagery? Evidence based on neural electrical activity is inconclusive as reflected in the “imagery debate” in cognitive science. Neural information and activity, however, also depend on regulated biophoton (optical) signaling. During encoding and retrieval of visual information, regulated electrical (redox) signals of neurons are converted into synchronized biophoton signals by bioluminescent radical processes. That is, visual information may be represented by regulated biophotons of mitochondrial networks in retinotopically organized cytochrome oxidase-rich neural networks within early visual areas. Therefore, we hypothesize that regulated biophotons can generate intrinsic optical representations in the primary visual cortex and then propagate variably degraded versions along cytochrome oxidase pathways during both perception and imagery. Testing this hypothesis requires to establish a methodology for measurement of in vivo and/or in vitro increases of biophoton emission in humans'' brain during phosphene inductions by transcranial magnetic stimulation and to compare the decrease in phosphene thresholds during transcranial magnetic stimulation and imagery. Our hypothesis provides a molecular mechanism for the visual buffer and for imagery as the prevalent communication mode (through optical signaling) within the brain. If confirmed empirically, this hypothesis could resolve the imagery debate and the underlying issue of continuity between perception and abstract thought. [Copyright &y& Elsevier]
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- 2009
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9. Spatio-temporal point-spread function of fMRI signal in human gray matter at 7 Tesla
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Shmuel, Amir, Yacoub, Essa, Chaimow, Denis, Logothetis, Nikos K., and Ugurbil, Kamil
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MAGNETIC resonance imaging , *VISUAL cortex , *BLOOD , *MEDICAL imaging systems - Abstract
Abstract: This study investigated the spatio-temporal properties of blood-oxygenation level-dependent (BOLD) functional MRI (fMRI) signals in gray matter, excluding the confounding, inaccurate contributions of large blood vessels. We quantified the spatial specificity of the BOLD response, and we investigated whether this specificity varies as a function of time from stimulus onset. fMRI was performed at 7 Tesla (T), where mapping signals of parenchymal origin are easily detected. Two abutting visual stimuli were adjusted to elicit responses centered on a flat gray matter region in V1. fMRI signals were sampled at high-resolution orthogonal to the retinotopic boundary between the representations of the stimuli. Signals from macro-vessels were masked out. Principal component analysis revealed that the first component in space accounted for 96.2±1.6% of the variance over time. The spatial profile of this time-invariant response was fitted with a model consisting of the convolution of a step function and a Gaussian point-spread-function (PSF). The mean full-width at half-maximal-height of the fitted PSF was 2.34±0.20 mm. Based on simulations of confounding effects, we estimate that BOLD PSF in human gray matter is smaller than 2 mm. A time-point to time-point analysis revealed that the PSF obtained during the 3rd (1.52 mm) and 4th (1.99 mm) seconds of stimulation were narrower than the mean PSF obtained from the 5th second on (2.42±0.15 mm). The position of the edge of the responding region was offset (1.72±0.07 mm) from the boundary of the stimulated region, indicating a spatial non-linearity. Simulations showed that the effective contrast between active and non-active columns is reduced 25-fold when imaged using a PSF whose width is equal to the cycle of the imaged columnar organization. Thus, the PSF of the hyper-oxygenated BOLD response in human gray matter is narrower than that reported at 1.5 T, where macro-vessels dominate the mapping signals. The initial phase of this response is more spatially specific than later phases. Data acquisition methods that suppress macro-vascular signals should increase the spatial specificity of BOLD fMRI. The choice of optimal stimulus duration represents a trade-off between the spatial specificity and the overhead associated with short stimulus duration. [Copyright &y& Elsevier]
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- 2007
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10. Spatial resolution of EEG cortical source imaging revealed by localization of retinotopic organization in human primary visual cortex
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Im, Chang-Hwan, Gururajan, Arvind, Zhang, Nanyin, Chen, Wei, and He, Bin
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ELECTROENCEPHALOGRAPHY , *ELECTRODIAGNOSIS , *VISUAL evoked response , *OCCIPITAL lobe - Abstract
Abstract: The aim of the present study is to investigate the spatial resolution of electroencephalography (EEG) cortical source imaging by localizing the retinotopic organization in the human primary visual cortex (V1). Retinotopic characteristics in V1 obtained from functional magnetic resonance imaging (fMRI) study were used as reference to assess the spatial resolution of EEG since fMRI can discriminate small changes in activation in visual field. It is well known that the activation of the early C1 component in the visual evoked potential (VEP) elicited by pattern onset stimuli coincides well with the activation in the striate cortex localized by fMRI. In the present experiments, we moved small circular checkerboard stimuli along horizontal meridian and compared the activations localized by EEG cortical source imaging with those from fMRI. Both fMRI and EEG cortical source imaging identified spatially correlated activity within V1 in each subject studied. The mean location error, between the fMRI-determined activation centers in V1 and the EEG source imaging activation peak estimated at equivalent C1 components (peak latency: 74.8±10.6ms), was 7mm (25% and 75% percentiles are 6.45mm and 8.4mm, respectively), which is less than the change in fMRI activation map by a 3° visual field change (7.8mm). Moreover, the source estimates at the earliest major VEP component showed statistically good correlation with those obtained by fMRI. The present results suggest that the spatial resolution of the EEG cortical source imaging can correctly discriminate cortical activation changes in V1 corresponding to less than 3° visual field changes. [Copyright &y& Elsevier]
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- 2007
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11. Stimulus- and Neural-Referred Visual Receptive Field Properties following Hemispherectomy: A Case Study Revisited
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Koen V. Haak, Hinke N. Halbertsma, and Frans W. Cornelissen
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REPRESENTATION ,genetic structures ,medicine.medical_treatment ,0302 clinical medicine ,Foveal ,MAPS ,PLASTICITY ,Visual Cortex ,education.field_of_study ,Brain Mapping ,220 Statistical Imaging Neuroscience ,OCCIPITAL LOBE ,Hemispherectomy ,Visual field ,medicine.anatomical_structure ,Neurology ,Female ,Psychology ,Research Article ,CORTEX ,Article Subject ,Population ,PATIENT ,Retina ,lcsh:RC321-571 ,03 medical and health sciences ,Young Adult ,All institutes and research themes of the Radboud University Medical Center ,RETINOTOPIC ORGANIZATION ,medicine ,Humans ,Visual Pathways ,education ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Vision, Ocular ,Neurodevelopmental disorders Donders Center for Medical Neuroscience [Radboudumc 7] ,STABILITY ,eye diseases ,Visual cortex ,Receptive field ,Retinotopy ,030221 ophthalmology & optometry ,Neurology (clinical) ,Visual Fields ,Occipital lobe ,Neuroscience ,030217 neurology & neurosurgery ,SYSTEM ,Photic Stimulation - Abstract
Damage to the visual system can result in (a partial) loss of vision, in response to which the visual system may functionally reorganize. Yet the timing, extent, and conditions under which this occurs are not well understood. Hence, studies in individuals with diverse congenital and acquired conditions and using various methods are needed to better understand this. In the present study, we examined the visual system of a young girl who received a hemispherectomy at the age of three and who consequently suffered from hemianopia. We did so by evaluating the corticocortical and retinocortical projections in the visual system of her remaining hemisphere. For the examination of these aspects, we analyzed the characteristics of the connective fields (“neural-referred” receptive fields) based on both resting-state (RS) and retinotopy data. The evaluation of RS data, reflecting brain activity independent from visual stimulation, is of particular interest as it is not biased by the patient’s atypical visual percept. We found that, primarily when the patient was at rest, the connective fields between V1 and both early and late visual areas were larger than normal. These abnormally large connective fields could be a sign either of functional reorganization or of unmasked suppressive feedback signals that are normally masked by interhemispheric signals. Furthermore, we confirmed our previous finding of abnormal retinocortical or “stimulus-referred” projections in both early and late visual areas. More specifically, we found an enlarged foveal representation and smaller population receptive fields. These differences could also be a sign of functional reorganization or rather a reflection of the interruption visual information that travels, via the remainder of the visual pathway, from the retina to the visual cortex. To conclude, while we do find indications for relatively subtle changes in visual field map properties, we found no evidence of large-scale reorganization—even though the patient could have benefitted from this. Our work suggests that at a later developmental stage, large-scale reorganization of the visual system no longer occurs, while small-scale properties may still change to facilitate adaptive processing and viewing strategies.
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- 2019
12. Functional reorganization of population receptive fields in a hemispherectomy patient with blindsight
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Loraine Georgy, Bert Jans, Marco Tamietto, Alain Ptito, MRI, RS: FPN CN 3, RS: FPN CN 5, and Medical and Clinical Psychology
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Drug Resistant Epilepsy ,REPRESENTATION ,genetic structures ,medicine.medical_treatment ,RESIDUAL VISION ,Audiology ,Blindness ,STRIATE CORTEX ,Visual processing ,Behavioral Neuroscience ,Postoperative Complications ,0302 clinical medicine ,Foveal ,Population receptive field (pRF) mapping ,Visual Cortex ,Brain Mapping ,education.field_of_study ,05 social sciences ,HUMANS ,Magnetic Resonance Imaging ,ABSENCE ,Receptive field (RF) size ,Visual field ,Hemispherectomy ,medicine.anatomical_structure ,STIMULI ,Visual Perception ,Female ,Psychology ,Adult ,medicine.medical_specialty ,Cognitive Neuroscience ,Population ,Experimental and Cognitive Psychology ,Blindsight ,Polar angle ,HEMIFIELD ,050105 experimental psychology ,Eccentricity ,Functional magnetic resonance imaging (fMRI) ,Retinotopic mapping ,03 medical and health sciences ,RETINOTOPIC ORGANIZATION ,Journal Article ,medicine ,0501 psychology and cognitive sciences ,VISUAL-FIELD ,education ,Vision, Ocular ,LESIONS ,Visual cortex ,Receptive field ,Visual Fields ,Photic Stimulation ,030217 neurology & neurosurgery - Abstract
Blindsight refers to the ability of some patients with destruction of the primary visual cortex (V1) to respond to stimuli presented in their clinically blind visual field despite lack of visual awareness. Here we tested a rare and well-known patient with blindsight following hemispherectomy, DR, who has had the entire cortex in the right hemisphere removed, and in whom the right superior colliculus is the only post-chiasmatic visual structure remaining intact. Compared to more traditional cases of blindsight after damage confined to V1, the study of blindsight in hemispherectomy has offered the invaluable opportunity to examine directly two outstanding questions: the contribution of the intact hemisphere to visual processing without awareness, and the nature of plastic and compensatory changes in these remaining contralesional visual areas. Population receptive field (pRF) mapping was used to define retinotopic maps, delineate the boundaries between the visual areas, examine changes in the sizes of receptive field centres within each visual area, and their variability as a function of eccentricity. Aside from the dorsal visual areas showing blurred borders between V2d and V3d, not otherwise detected with perimetric mapping, the retinotopic maps of DR did not differ substantially from those of three matched healthy controls. Interestingly, those dorsal compartments showed a significant increase in the RF sizes toward values typical of higher-order processing cortices, while no differences were observed in the corresponding ventral visual areas. Findings showed that whereas receptive field sizes at foveal and parafoveal eccentricities (≤ 4°) were not measurably altered, the pRF size increased by ~ 270% at 4-6° of eccentricity, and the size difference reached ~ 300% between 8° and 10°. We interpret these findings to suggest that an increase in pRF sizes could be indicative of cerebral plasticity involving the retinotopic reorganization of the dorsal visual areas.
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- 2019
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13. A cross-validated cytoarchitectonic atlas of the human ventral visual stream
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Rosenke, Mona, Rosenke, Mona, Weiner, Kevin S, Barnett, Michael A, Zilles, Karl, Amunts, Katrin, Goebel, Rainer, Grill-Spector, Kalanit, Rosenke, Mona, Rosenke, Mona, Weiner, Kevin S, Barnett, Michael A, Zilles, Karl, Amunts, Katrin, Goebel, Rainer, and Grill-Spector, Kalanit
- Abstract
The human ventral visual stream consists of several areas that are considered processing stages essential for perception and recognition. A fundamental microanatomical feature differentiating areas is cytoarchitecture, which refers to the distribution, size, and density of cells across cortical layers. Because cytoarchitectonic structure is measured in 20-micron-thick histological slices of postmortem tissue, it is difficult to assess (a) how anatomically consistent these areas are across brains and (b) how they relate to brain parcellations obtained with prevalent neuroimaging methods, acquired at the millimeter and centimeter scale. Therefore, the goal of this study was to (a) generate a cross-validated cytoarchitectonic atlas of the human ventral visual stream on a whole brain template that is commonly used in neuroimaging studies and (b) to compare this atlas to a recently published retinotopic parcellation of visual cortex (Wang et al., 2014). To achieve this goal, we generated an atlas of eight cytoarchitectonic areas: four areas in the occipital lobe (hOc1-hOc4v) and four in the fusiform gyrus (FG1-FG4), then we tested how the different alignment techniques affect the accuracy of the resulting atlas. Results show that both cortex-based alignment (CBA) and nonlinear volumetric alignment (NVA) generate an atlas with better cross-validation performance than affine volumetric alignment (AVA). Additionally, CBA outperformed NVA in 6/8 of the cytoarchitectonic areas. Finally, the comparison of the cytoarchitectonic atlas to a retinotopic atlas shows a clear correspondence between cytoarchitectonic and retinotopic areas in the ventral visual stream. The successful performance of CBA suggests a coupling between cytoarchitectonic areas and macroanatomical landmarks in the human ventral visual stream, and furthermore, that this coupling can be utilized for generating an accurate group atlas. In addition, the coupling between cytoarchitecture and retinotopy highlight
- Published
- 2018
14. Retinal inputs and laminar distributions of the dorsal lateral geniculate nucleus relay cells in the eastern chipmunk ( Tamias sibiricus asiaticus).
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Morigiwa, K., Sawai, H., Wakakuwa, K., Mitani-Yamanishi, Y., and Fukuda, Y.
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Retinal inputs and their laminar distributions in the dorsal lateral geniculate nucleus (LGNd) of the eastern chipmunk ( Tamias sibiricus asiaticus) were studied using histological and microelectrode recording techniques. A previous anatomical study (Fukuda et al. 1986a) indicated that the chipmunk LGNd had five laminae: contralaterally (contra) innervated lamina 1 and ipsilaterally (ipsi) innervated lamina 2 in its ventromedial part; laminae 3a (contra), 3b (ipsi) and 3c (contra) in its dorsolateral part. We have confirmed this finding in our present anatomical study and have also noted another ipsilaterally innervated thin lamina 0, medial to lamina 1. In our electrophysiological study, however, we were unable to record units from lamina 0 and to investigate it functionally. We recorded 232 units from laminae 1, 2 and the 3 complex, of which 95 were identified as Y-like, 46 as W-like, 15 as X-like, and 8 as mixed Y/W-like cells; the rest were either unclassified or visually unresponsive. In laminae 1 and 2, only Y-like and X-like cells were recorded, whereas in the laminae 3 complex W-like cells were recorded as well. The results suggest that the chipmunk laminae 1,2 and 3 complex correspond relatively well to the cat laminae A, A1 and C complex, respectively. In the chipmunk LGNd, however, there were more Y-like cells in laminae 1 and 2, and a few X-like cells of which some were color sensitive. Also, lamina 3a had a concentration of mixed-type cells with Y-like receptive field properties and W-like OX latencies. As for retinotopy, the dorsoventral transition of the contralateral visual field (laminae 1, 3a, 3c) is represented along the dorsoventral dimension of the chipmunk LGNd, whereas the temporonasal transition is represented in the rostrocaudal direction. Receptive field positions of the ipsilaterally innervated relay cells are limited to the central overlapping field of the contralateral visual fields of both eyes. Relay cells with visual fields having elevations of below -20° had relatively fast latency range and Ylike properties. [ABSTRACT FROM AUTHOR]
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- 1988
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15. A cross-validated cytoarchitectonic atlas of the human ventral visual stream
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Kalanit Grill-Spector, Rainer Goebel, Katrin Amunts, Michael Barnett, Kevin S. Weiner, Mona Rosenke, Karl Zilles, Netherlands Institute for Neuroscience (NIN), RS: FPN CN 1, and Vision
- Subjects
0301 basic medicine ,ACQUIRED PROSOPAGNOSIA ,Male ,Visual perception ,Magnetic Resonance Imaging/methods ,0302 clinical medicine ,Human brain atlas ,Occipital Lobe/cytology ,Neuroimaging/methods ,Temporal cortex ,Retinotopy ,2 EXTRASTRIATE AREAS ,HUMAN BRAIN ,Magnetic Resonance Imaging ,Temporal Lobe ,medicine.anatomical_structure ,Neurology ,Cytoarchitecture ,Visual Perception ,Temporal Lobe/cytology ,Female ,Occipital Lobe ,Psychology ,Adult ,Cognitive Neuroscience ,HUMAN OCCIPITOTEMPORAL CORTEX ,OCCIPITAL CORTEX ,Neuroimaging ,Article ,Objecet recognition ,03 medical and health sciences ,Atlases as Topic ,RETINOTOPIC ORGANIZATION ,medicine ,Journal Article ,Humans ,Visual cortex ,FUSIFORM FACE AREA ,ddc:610 ,Fusiform gyrus ,TEMPORAL CORTEX ,Fusiform face area ,Brain parcellation ,Cortex-based alignment ,030104 developmental biology ,Occipital lobe ,HUMAN CEREBRAL-CORTEX ,Neuroscience ,DIFFERENTIAL DEVELOPMENT ,030217 neurology & neurosurgery - Abstract
The human ventral visual stream consists of several areas that are considered processing stages essential for perception and recognition. A fundamental microanatomical feature differentiating areas is cytoarchitecture, which refers to the distribution, size, and density of cells across cortical layers. Because cytoarchitectonic structure is measured in 20-micron-thick histological slices of postmortem tissue, it is difficult to assess (a) how anatomically consistent these areas are across brains and (b) how they relate to brain parcellations obtained with prevalent neuroimaging methods, acquired at the millimeter and centimeter scale. Therefore, the goal of this study was to (a) generate a cross-validated cytoarchitectonic atlas of the human ventral visual stream on a whole brain template that is commonly used in neuroimaging studies and (b) to compare this atlas to a recently published retinotopic parcellation of visual cortex (Wang et al., 2014). To achieve this goal, we generated an atlas of eight cytoarchitectonic areas: four areas in the occipital lobe (hOc1-hOc4v) and four in the fusiform gyrus (FG1-FG4), then we tested how the different alignment techniques affect the accuracy of the resulting atlas. Results show that both cortex-based alignment (CBA) and nonlinear volumetric alignment (NVA) generate an atlas with better cross-validation performance than affine volumetric alignment (AVA). Additionally, CBA outperformed NVA in 6/8 of the cytoarchitectonic areas. Finally, the comparison of the cytoarchitectonic atlas to a retinotopic atlas shows a clear correspondence between cytoarchitectonic and retinotopic areas in the ventral visual stream. The successful performance of CBA suggests a coupling between cytoarchitectonic areas and macroanatomical landmarks in the human ventral visual stream, and furthermore, that this coupling can be utilized for generating an accurate group atlas. In addition, the coupling between cytoarchitecture and retinotopy highlights the potential use of this atlas in understanding how anatomical features contribute to brain function. We make this cytoarchitectonic atlas freely available in both BrainVoyager and FreeSurfer formats (http://vpnl.stanford.edu/vcAtlas). The availability of this atlas will enable future studies to link cytoarchitectonic organization to other parcellations of the human ventral visual stream with potential to advance the understanding of this pathway in typical and atypical populations.
- Published
- 2018
16. Abnormal visual field maps in human cortex
- Subjects
RECURRENT NETWORK MODEL ,Visual field maps ,Cortical reorganization ,Hemispherectomy ,Review ,MACULAR DEGENERATION ,FUNCTIONAL MRI ,HUMAN BRAIN ,CORTICAL MAPS ,RETINOTOPIC ORGANIZATION ,Case report ,RECEPTIVE-FIELD ,V1 NEURONS ,HUMAN CEREBRAL-CORTEX ,REORGANIZATION - Abstract
Human visual cortex contains maps of the visual field. Much research has been dedicated to answering whether and when these visual field maps change if critical components of the visual circuitry are damaged. Here, we first provide a focused mini-review of the functional magnetic resonance imaging (fMRI) studies that have evaluated the human cortical visual field maps in the face of retinal lesions, brain injury, and atypical retinocortical projections. We find that there is a fair body of research that has found abnormal fMRI activity, but also that this abnormal activity does not necessarily stem from cortical remapping. The abnormal fMRI activity can often be explained in terms of task effects and/or the uncovering of normally hidden system dynamics. We then present the case of a 16-year-old patient who lost the entire left cerebral hemisphere at age three for treatment of chronic focal encephalitis (Rasmussen syndrome) and intractable epilepsy. Using an fMRI retinotopic mapping procedure and population receptive field (pRF) modeling, we found that (1) despite the long period since the hemispherectomy, the retinotopic organization of early visual cortex remained unaffected by the removal of an entire cerebral hemisphere, and (2) the intact lateral occipital cortex contained an exceptionally large representation of the center of the visual field. The same method also indicates that the neuronal receptive fields in these lateral occipital brain regions are extraordinarily small. These features are clearly abnormal, but again they do not necessarily stem from cortical remapping. For example, the abnormal features can also be explained by the notion that the hemispherectomy took place during a critical period in the development of the lateral occipital cortex and therefore arrested its normal development. Thus, caution should be exercised when interpreting abnormal fMRI activity as a marker of cortical remapping; there are often other explanations. (C) 2012 Elsevier Ltd. All rights reserved.
- Published
- 2014
17. Abnormal visual field maps in human cortex: A mini-review and a case report
- Author
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Koen V. Haak, Frans W. Cornelissen, Remco J. Renken, Johannes Borgstein, Dave R. M. Langers, and Pim van Dijk
- Subjects
Male ,Visual field maps ,Cortical reorganization ,Adolescent ,Hemispherectomy ,genetic structures ,Cognitive Neuroscience ,medicine.medical_treatment ,Cortical remapping ,Experimental and Cognitive Psychology ,Review ,Functional Laterality ,CORTICAL MAPS ,RETINOTOPIC ORGANIZATION ,Cortex (anatomy) ,Case report ,Image Processing, Computer-Assisted ,medicine ,Humans ,RECEPTIVE-FIELD ,V1 NEURONS ,Visual Cortex ,RECURRENT NETWORK MODEL ,Brain Mapping ,Epilepsy ,medicine.diagnostic_test ,Human brain ,MACULAR DEGENERATION ,FUNCTIONAL MRI ,HUMAN BRAIN ,Magnetic Resonance Imaging ,Psychosurgery ,Visual field ,Neuropsychology and Physiological Psychology ,medicine.anatomical_structure ,Visual cortex ,Receptive field ,Visual Fields ,HUMAN CEREBRAL-CORTEX ,Psychology ,Functional magnetic resonance imaging ,Neuroscience ,REORGANIZATION ,Photic Stimulation - Abstract
Human visual cortex contains maps of the visual field. Much research has been dedicated to answering whether and when these visual field maps change if critical components of the visual circuitry are damaged. Here, we first provide a focused mini-review of the functional magnetic resonance imaging (fMRI) studies that have evaluated the human cortical visual field maps in the face of retinal lesions, brain injury, and atypical retinocortical projections. We find that there is a fair body of research that has found abnormal fMRI activity, but also that this abnormal activity does not necessarily stem from cortical remapping. The abnormal fMRI activity can often be explained in terms of task effects and/or the uncovering of normally hidden system dynamics. We then present the case of a 16-year-old patient who lost the entire left cerebral hemisphere at age three for treatment of chronic focal encephalitis (Rasmussen syndrome) and intractable epilepsy. Using an fMRI retinotopic mapping procedure and population receptive field (pRF) modeling, we found that (1) despite the long period since the hemispherectomy, the retinotopic organization of early visual cortex remained unaffected by the removal of an entire cerebral hemisphere, and (2) the intact lateral occipital cortex contained an exceptionally large representation of the center of the visual field. The same method also indicates that the neuronal receptive fields in these lateral occipital brain regions are extraordinarily small. These features are clearly abnormal, but again they do not necessarily stem from cortical remapping. For example, the abnormal features can also be explained by the notion that the hemispherectomy took place during a critical period in the development of the lateral occipital cortex and therefore arrested its normal development. Thus, caution should be exercised when interpreting abnormal fMRI activity as a marker of cortical remapping; there are often other explanations. (C) 2012 Elsevier Ltd. All rights reserved.
- Published
- 2014
18. Organisation rétinotopique des structures visuelles révélée par imagerie optique cérébrale chez le rat normal
- Author
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Nassim, Marouane and Casanova, Christian
- Subjects
Cortex visuelle primaire ,Ondes de Mayer ,Facteur cortical de grossissement ,Retinotopic organization ,Acuity ,Analyse de Fourier ,Collicule supérieure ,Continuous stimulation ,Organisation rétinotopique ,Fourier analysis ,Primary visual cortex ,Bruit vasculaire ,Imagerie optique ,Cortical magnification factors ,Optical imagery ,Acuité ,Vascular noise ,Mayer waves ,Superior colliculus ,Stimulation continue - Abstract
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.
- Published
- 2009
19. Target recognition and dynamics of axonal growth in the retinotectal system of fish
- Author
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Claudia A.O. Stuermer
- Subjects
Superior Colliculi ,Retinotopic organization ,Position-dependent properties on cell surfaces ,Biology ,Retina ,chemistry.chemical_compound ,Time lapse video-microscopy ,ddc:570 ,medicine ,Animals ,Neuronal Plasticity ,Cluster of differentiation ,Regeneration (biology) ,Fishes ,Membrane Proteins ,Axonal pathways ,Retinal ,General Medicine ,Embryonic stem cell ,Axons ,Nerve Regeneration ,Ganglion ,Cell biology ,medicine.anatomical_structure ,nervous system ,chemistry ,Optic nerve ,Neural cell adhesion molecule ,In vitro assay ,Tectum ,Neuroscience - Abstract
Embryonic and regenerating retinal axons in fish are able to seek out their retinotopic target sites in the tectum. Neither a specific preordering of axons in the retinotectal pathway nor activity-dependent axon-target interactions are required for appropriate previous axonal targeting. Axon-target recognition appears to be predominantly mediated by positional cell surface markers. The discrimination of position-dependent differences by retinal axons in a special in vitro assay is consistent with this concept.To understand retinal previous axonal regeneration we have analyzed the glial cells of the fish optic nerve and the expression of growth-associated cell surface molecules on the regenerating axons. The surfaces of the glial cells identified as oligodendrocytes are excellent substrates for the elongation of regenerating axons. Raising monoclonal antibodies we have found 3 cell surface proteins specific for growing axons. In the normal adult goldfish optic nerve, these proteins are only expressed by the few new axons from the newborn ganglion cells at the retinal margin. They are re-expressed on all axons during regeneration. A known cell surface molecule, NCAM, is expressed in a similar, specific spatiotemporal pattern on the fish retinal axons and may in normal nerves contribute to the establishment of the age-related fiber association. Whether the re-expression of NCAM and the antigens detected by the novel monoclonal antibodies are functionally involved in previous axonal growth and regeneration remains to be investigated.
- Published
- 1990
20. Neuromagnetic source localization and superposition of responses reveal retinotopic organization of extrastriate cortex in humans
- Author
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Supek, Selma, Aine, C., Ranken, D., Best, E., Flynn, E.R., Wood, C.C., and Thakor, Nitish
- Subjects
neuromagnetic data ,retinotopic organization - Abstract
It is investigated how the neuromagnetic source localization and superposition of responses reveal retinotopic organization of extrastriate cortex in humans.
- Published
- 1997
21. Partial Correlation-Based Retinotopically Organized Resting-State Functional Connectivity Within and Between Areas of the Visual Cortex Reflects More Than Cortical Distance.
- Author
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Dawson DA, Lam J, Lewis LB, Carbonell F, Mendola JD, and Shmuel A
- Subjects
- Humans, Male, Brain Mapping, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Visual Cortex physiology, Visual Fields physiology, Visual Pathways physiology
- Abstract
Numerous studies have demonstrated functional magnetic resonance imaging (fMRI)-based resting-state functional connectivity (RSFC) between cortical areas. Recent evidence suggests that synchronous fluctuations in blood oxygenation level-dependent fMRI reflect functional organization at a scale finer than that of visual areas. In this study, we investigated whether RSFCs within and between lower visual areas are retinotopically organized and whether retinotopically organized RSFC merely reflects cortical distance. Subjects underwent retinotopic mapping and separately resting-state fMRI. Visual areas V1, V2, and V3, were subdivided into regions of interest (ROIs) according to quadrants and visual field eccentricity. Functional connectivity (FC) was computed based on Pearson's linear correlation (correlation), and Pearson's linear partial correlation (correlation between two time courses after the time courses from all other regions in the network are regressed out). Within a quadrant, within visual areas, all correlation and nearly all partial correlation FC measures showed statistical significance. Consistently in V1, V2, and to a lesser extent in V3, correlation decreased with increasing eccentricity separation. Consistent with previously reported monkey anatomical connectivity, correlation/partial correlation values between regions from adjacent areas (V1-V2 and V2-V3) were higher than those between nonadjacent areas (V1-V3). Within a quadrant, partial correlation showed consistent significance between regions from two different areas with the same or adjacent eccentricities. Pairs of ROIs with similar eccentricity showed higher correlation/partial correlation than pairs distant in eccentricity. Between dorsal and ventral quadrants, partial correlation between common and adjacent eccentricity regions within a visual area showed statistical significance; this extended to more distant eccentricity regions in V1. Within and between quadrants, correlation decreased approximately linearly with increasing distances separating the tested ROIs. Partial correlation showed a more complex dependence on cortical distance: it decreased exponentially with increasing distance within a quadrant, but was best fit by a quadratic function between quadrants. We conclude that RSFCs within and between lower visual areas are retinotopically organized. Correlation-based FC is nonselectively high across lower visual areas, even between regions that do not share direct anatomical connections. The mechanisms likely involve network effects caused by the dense anatomical connectivity within this network and projections from higher visual areas. FC based on partial correlation, which minimizes network effects, follows expectations based on direct anatomical connections in the monkey visual cortex better than correlation. Last, partial correlation-based retinotopically organized RSFC reflects more than cortical distance effects.
- Published
- 2016
- Full Text
- View/download PDF
22. Retinotopic organization of extra-retinal saccade-related input to the visual cortex in the cat
- Author
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Vanni-Mercier, G. and Magnin, M.
- Published
- 1982
- Full Text
- View/download PDF
23. Cortical and thalamic connectivity of temporal visual cortical areas 20a and 20b of the domestic ferret (Mustela putorius furo)
- Author
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Leigh-Anne Dell, Giorgio M. Innocenti, Paul R. Manger, and Claus C. Hilgetag
- Subjects
posterior parietal cortex ,Thalamus ,Dorsal thalamus ,Posterior parietal cortex ,cat ,integration ,Biology ,principles ,Auditory cortex ,cortical evolution ,dorsal ,corpus callosum ,medicine ,Prefrontal cortex ,prefrontal cortex ,projections ,hodology ,mustela putorious furo ,visual processing networks ,biology.organism_classification ,Visual cortex ,medicine.anatomical_structure ,Mustela putorius ,retinotopic organization ,network ,Connectome ,carnivora ,afferent connections ,Neuroscience - Abstract
The present study describes the ipsilateral and contralateral cortico-cortical and cortico-thalamic connectivity of the temporal visual areas 20a and 20b in the ferret using standard anatomical tract-tracing methods. The two temporal visual areas are strongly interconnected, but area 20a is primarily connected to the occipital visual areas, whereas area 20b maintains more widespread connections with the occipital, parietal and suprasylvian visual areas and the secondary auditory cortex. The callosal connectivity, although homotopic, consists mainly of very weak anterograde labelling which was more widespread in area 20a than area 20b. Although areas 20a and 20b are well connected with the visual dorsal thalamus, the injection into area 20a resulted in more anterograde label, whereas more retrograde label was observed in the visual thalamus following the injection into area 20b. Most interestingly, comparisons to previous connectional studies of cat areas 20a and 20b reveal a common pattern of connectivity of the temporal visual cortex in carnivores, where the posterior parietal cortex and the central temporal region (PMLS) provide network points required for dorsal and ventral stream interaction enroute to integration in the prefrontal cortex. This pattern of network connectivity is not dissimilar to that observed in primates, which highlights the ferret as a useful animal model to understand visual sensory integration between the dorsal and ventral streams. This data will contribute to the Ferretome (www.ferretome.org) to facilitate cross species analysis of brain connectomes and wiring principles of the brain.
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