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Yang Y, Chen K, Rosa MGP, Yu HH, Kuang LR, Yang J. Visual response characteristics of neurons in the second visual area of marmosets. Neural Regen Res 2021; 16:1871-1876. [PMID: 33510095 PMCID: PMC8328785 DOI: 10.4103/1673-5374.303043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The physiological characteristics of the marmoset second visual area (V2) are poorly understood compared with those of the primary visual area (V1). In this study, we observed the physiological response characteristics of V2 neurons in four healthy adult marmosets using intracortical tungsten microelectrodes. We recorded 110 neurons in area V2, with receptive fields located between 8° and 15° eccentricity. Most (88.2%) of these neurons were orientation selective, with half-bandwidths typically ranging between 10° and 30°. A significant proportion of neurons (28.2%) with direction selectivity had a direction index greater than 0.5. The vast majority of V2 neurons had separable spatial frequency and temporal frequency curves and, according to this criterion, they were not speed selective. The basic functional response characteristics of neurons in area V2 resemble those found in area V1. Our findings show that area V2 together with V1 are important in primate visual processing, especially in locating objects in space and in detecting an object’s direction of motion. The methods used in this study were approved by the Monash University Animal Ethics Committee, Australia (MARP 2009-2011) in 2009.
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Affiliation(s)
- Yin Yang
- Department of Ophthalmology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital; College of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan Province, China
| | - Ke Chen
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, Sichuan Province, China
| | - Marcello G P Rosa
- Department of Physiology, Monash University, Melbourne, VIC, Australia
| | - Hsin-Hao Yu
- Department of Physiology, Monash University, Melbourne, VIC, Australia
| | - Li-Rong Kuang
- Chengdu Medical College, Chengdu, Sichuan Province, China
| | - Jie Yang
- College of Medicine, University of Electronic Science and Technology of China; Department of Neurology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, Sichuan Province, China
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2
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Khalil R, Saint Louis MRJ, Alsuwaidi S, Levitt JB. Visual Corticocortical Inputs to Ferret Area 18. Front Neuroanat 2020; 14:581478. [PMID: 33117134 PMCID: PMC7574738 DOI: 10.3389/fnana.2020.581478] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 09/16/2020] [Indexed: 11/13/2022] Open
Abstract
Visual cortical areas in the adult mammalian brain are linked by a network of interareal feedforward and feedback circuits. We investigated the topography of feedback projections to ferret (Mustela putorius furo) area 18 from extrastriate areas 19, 21, and Ssy. Our objective was to characterize the anatomical organization of the extrastriate feedback pool to area 18. We also wished to determine if feedback projections to area 18 share similar features as feedback projections to area 17. We injected the tracer cholera toxin B subunit (CTb) into area 18 of adult ferrets to visualize the distribution and pattern of retrogradely labeled cells in extrastriate cortex. We find several similarities to the feedback projection to area 17: (i) Multiple visual cortical areas provide feedback to area 18: areas 19, 21, Ssy, and weaker inputs from posterior parietal and lateral temporal visual areas. Within each area a greater proportion of feedback projections arises from the infragranular than from the supragranular layers. (ii) The cortical area immediately rostral to area 18 provides the greatest proportion of total cortical feedback, and has the greatest peak density of cells providing feedback to area 18. (iii) The spacing (peak cell density and nearest neighbor distances) of cells in extrastriate cortex providing feedback to areas 17 and 18 are similar. However, peak density of feedback cells to area 18 is comparable in the supra- and infragranular layers, whereas peak density of feedback cells to area 17 is higher in the infragranular layers. Another prominent difference is that dorsal area 18 receives a cortical input that area 17 does not: from ventral cortex representing the upper visual field; this appears to be roughly 25% of the feedback input to area 18. Lastly, area 17 receives a greater proportion of cortical feedback from area 21 than from Ssy, whereas area 18 receives more feedback from Ssy than from area 21. While the organization of feedback projections from extrastriate cortex to areas 17 and 18 is broadly similar, the main difference in input topography might arise due to differences in visual field representations of the two areas.
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Affiliation(s)
- Reem Khalil
- Department of Biology, Chemistry and Environmental Sciences, American University of Sharjah, Sharjah, United Arab Emirates.,Department of Biology, City College of New York, New York, NY, United States
| | | | - Shaima Alsuwaidi
- Department of Biology, Chemistry and Environmental Sciences, American University of Sharjah, Sharjah, United Arab Emirates.,The Neuro, Montreal Neurological Institute-Hospital, McGill University, Montreal, QC, Canada
| | - Jonathan B Levitt
- Department of Biology, City College of New York, New York, NY, United States.,Graduate Center of the City University of New York, New York, NY, United States
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3
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Liu C, Ye FQ, Newman JD, Szczupak D, Tian X, Yen CCC, Majka P, Glen D, Rosa MGP, Leopold DA, Silva AC. A resource for the detailed 3D mapping of white matter pathways in the marmoset brain. Nat Neurosci 2020; 23:271-280. [PMID: 31932765 PMCID: PMC7007400 DOI: 10.1038/s41593-019-0575-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 12/10/2019] [Indexed: 12/19/2022]
Abstract
While the fundamental importance of the white matter in supporting neuronal communication is well known, existing publications of primate brains do not feature a detailed description of its complex anatomy. The main barrier to achieving this is that existing primate neuroimaging data have insufficient spatial resolution to resolve white matter pathways fully. Here we present a resource that allows detailed descriptions of white matter structures and trajectories of fiber pathways in the marmoset brain. The resource includes: (1) the highest-resolution diffusion-weighted MRI data available to date, which reveal white matter features not previously described; (2) a comprehensive three-dimensional white matter atlas depicting fiber pathways that were either omitted or misidentified in previous atlases; and (3) comprehensive fiber pathway maps of cortical connections combining diffusion-weighted MRI tractography and neuronal tracing data. The resource, which can be downloaded from marmosetbrainmapping.org, will facilitate studies of brain connectivity and the development of tractography algorithms in the primate brain.
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Affiliation(s)
- Cirong Liu
- Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA.
- Department of Neurobiology, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA.
| | - Frank Q Ye
- Neurophysiology Imaging Facility, National Institute of Mental Health, National Institute of Neurological Disorders and Stroke, and National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - John D Newman
- Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
- Section on Quantitative Imaging and Tissue Sciences, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Diego Szczupak
- Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
- Department of Neurobiology, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
| | - Xiaoguang Tian
- Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
- Department of Neurobiology, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
| | - Cecil Chern-Chyi Yen
- Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Piotr Majka
- Laboratory of Neuroinformatics, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Warsaw, Poland
- ARC Centre of Excellence for Integrative Brain Function, Clayton, Melbourne, Victoria, Australia
| | - Daniel Glen
- Scientific and Statistical Computing Core, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, MD, USA
| | - Marcello G P Rosa
- ARC Centre of Excellence for Integrative Brain Function, Clayton, Melbourne, Victoria, Australia
- Neuroscience Program, Monash Biomedicine Discovery Institute, Clayton, Melbourne, Victoria, Australia
| | - David A Leopold
- Neurophysiology Imaging Facility, National Institute of Mental Health, National Institute of Neurological Disorders and Stroke, and National Eye Institute, National Institutes of Health, Bethesda, MD, USA
- Section on Cognitive Neurophysiology and Imaging, Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Afonso C Silva
- Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA.
- Department of Neurobiology, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA.
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4
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Pálfi E, Zalányi L, Ashaber M, Palmer C, Kántor O, Roe AW, Friedman RM, Négyessy L. Connectivity of neuronal populations within and between areas of primate somatosensory cortex. Brain Struct Funct 2018; 223:2949-2971. [PMID: 29725759 DOI: 10.1007/s00429-018-1671-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 04/21/2018] [Indexed: 11/25/2022]
Abstract
Functions of the cerebral cortex emerge via interactions of horizontally distributed neuronal populations within and across areas. However, the connectional underpinning of these interactions is not well understood. The present study explores the circuitry of column-size cortical domains within the hierarchically organized somatosensory cortical areas 3b and 1 using tract tracing and optical intrinsic signal imaging (OIS). The anatomical findings reveal that feedforward connections exhibit high topographic specificity, while intrinsic and feedback connections have a more widespread distribution. Both intrinsic and inter-areal connections are topographically oriented across the finger representations. Compared to area 3b, the low clustering of connections and small cortical magnification factor supports that the circuitry of area 1 scaffolds a sparse functional representation that integrates peripheral information from a large area that is fed back to area 3b. Fast information exchange between areas is ensured by thick axons forming a topographically organized, reciprocal pathway. Moreover, the highest density of projecting neurons and groups of axon arborization patches corresponds well with the size and locations of the functional population response reported by OIS. The findings establish connectional motifs at the mesoscopic level that underpin the functional organization of the cerebral cortex.
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Affiliation(s)
- E Pálfi
- Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, 1094, Hungary
| | - L Zalányi
- Complex Systems and Computational Neuroscience Group, Wigner Research Centre for Physics, Hungarian Academy of Sciences, Konkoly-Thege Miklós út 29-33, Budapest, 1121, Hungary
| | - M Ashaber
- Department of Physiology and Biochemistry, Faculty of Veterinary Science, Szent István University, Budapest, 1078, Hungary
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
| | - C Palmer
- Department of Mathematical Sciences, University of Montana, Missoula, MT, 59812, USA
| | - O Kántor
- Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, 1094, Hungary
- Department of Neuroanatomy, Faculty of Medicine, Institute of Anatomy and Cell Biology, University of Freiburg, 79104, Freiburg, Germany
| | - A W Roe
- Division of Neuroscience, Oregon Health and Science University, Portland, OR, 97006, USA
- Interdisciplinary Institute of Neuroscience and Technology, Zhejiang University, Hangzhou, 310029, China
| | - R M Friedman
- Division of Neuroscience, Oregon Health and Science University, Portland, OR, 97006, USA
| | - L Négyessy
- Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, 1094, Hungary.
- Complex Systems and Computational Neuroscience Group, Wigner Research Centre for Physics, Hungarian Academy of Sciences, Konkoly-Thege Miklós út 29-33, Budapest, 1121, Hungary.
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5
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Li X, Zhu Q, Janssens T, Arsenault JT, Vanduffel W. In Vivo Identification of Thick, Thin, and Pale Stripes of Macaque Area V2 Using Submillimeter Resolution (f)MRI at 3 T. Cereb Cortex 2017; 29:544-560. [DOI: 10.1093/cercor/bhx337] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 11/29/2017] [Indexed: 11/14/2022] Open
Affiliation(s)
- Xiaolian Li
- Laboratory of Neuro- and Psychophysiology, Department of Neurosciences, KU Leuven Medical School, Leuven, Belgium
| | - Qi Zhu
- Laboratory of Neuro- and Psychophysiology, Department of Neurosciences, KU Leuven Medical School, Leuven, Belgium
| | - Thomas Janssens
- Laboratory of Neuro- and Psychophysiology, Department of Neurosciences, KU Leuven Medical School, Leuven, Belgium
- Current address: Siemens Healthcare Belgium, Beersel, Belgium
| | - John T Arsenault
- Laboratory of Neuro- and Psychophysiology, Department of Neurosciences, KU Leuven Medical School, Leuven, Belgium
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Wim Vanduffel
- Laboratory of Neuro- and Psychophysiology, Department of Neurosciences, KU Leuven Medical School, Leuven, Belgium
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Radiology, Harvard Medical School, Boston, MA, USA
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6
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Abstract
As highlighted by several contributions to this special issue, there is still ongoing debate about the number, exact location, and boundaries of the visual areas located in cortex immediately rostral to the second visual area (V2), i.e., the “third tier” visual cortex, in primates. In this review, we provide a historical overview of the main ideas that have led to four models of third tier cortex organization, which are at the center of today's debate. We formulate specific predictions of these models, and compare these predictions with experimental evidence obtained primarily in New World primates. From this analysis, we conclude that only one of these models (the “multiple-areas” model) can accommodate the breadth of available experimental evidence. According to this model, most of the third tier cortex in New World primates is occupied by two distinct areas, both representing the full contralateral visual quadrant: the dorsomedial area (DM), restricted to the dorsal half of the third visual complex, and the ventrolateral posterior area (VLP), occupying its ventral half and a substantial fraction of its dorsal half. DM belongs to the dorsal stream of visual processing, and overlaps with macaque parietooccipital (PO) area (or V6), whereas VLP belongs to the ventral stream and overlaps considerably with area V3 proposed by others. In contrast, there is substantial evidence that is inconsistent with the concept of a single elongated area V3 lining much of V2. We also review the experimental evidence from macaque monkey and humans, and propose that, once the data are interpreted within an evolutionary-developmental context, these species share a homologous (but not necessarily identical) organization of the third tier cortex as that observed in New World monkeys. Finally, we identify outstanding issues, and propose experiments to resolve them, highlighting in particular the need for more extensive, hypothesis-driven investigations in macaque and humans.
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7
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Corticocortical connection patterns reveal two distinct visual cortical areas bordering dorsal V2 in marmoset monkey. Vis Neurosci 2016; 32:E012. [PMID: 26423121 PMCID: PMC5301919 DOI: 10.1017/s0952523815000097] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The organization of the cortex located immediately anterior to the second visual area (V2), i.e., the third tier visual cortex, remains controversial, especially in New World primates. In particular, there is lack of consensus regarding the exact location and extent of the lower visual quadrant representation of the third visual area V3 (or ventrolateral posterior –VLP – of a different nomenclature). Microelectrode and connectional mapping studies have revealed the existence of an upper visual quadrant representation abutting dorsal V2 anteriorly, and bordered medially and laterally by representations of the lower visual quadrant. It remains unclear whether these lower field regions are both part of a single area V3, which is split into two patches by an interposed region of upper field representation, or whether they are the lower field representations of two different areas, the dorsomedial area (DM) and area V3/VLP, respectively. To address this question, we quantitatively analyzed the patterns of corticocortical afferent connections labeled by tracer injections targeted to these two lower field regions in the dorsal aspect of the third tier cortex. We found different inter-areal connectivity patterns arising from these two regions, strongly suggesting that they belong to two different visual areas. In particular, our results indicate that the dorsal aspect of the third tier cortex consists of two distinct areas: a full area DM, representing the lower quadrant medially, and the upper quadrant laterally, and the lower quadrant representation of V3/VLP, located laterally to upper field DM. DM is predominantly connected with areas of the dorsal visual stream, and V3/VLP with areas of the ventral stream. These results prompt further functional investigations of the third tier cortex, as previous studies of this cortical territory may have pooled response properties of two very different areas into a single area V3.
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8
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Input and output gain modulation by the lateral interhemispheric network in early visual cortex. J Neurosci 2015; 35:7682-94. [PMID: 25995459 DOI: 10.1523/jneurosci.4154-14.2015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Neurons in the cerebral cortex are constantly integrating different types of inputs. Dependent on their origin, these inputs can be modulatory in many ways and, for example, change the neuron's responsiveness, sensitivity, or selectivity. To investigate the modulatory role of lateral input from the same level of cortical hierarchy, we recorded in the primary visual cortex of cats while controlling synaptic input from the corresponding contralateral hemisphere by reversible deactivation. Most neurons showed a pronounced decrease in their response to a visual stimulus of different contrasts and orientations. This indicates that the lateral network acts via an unspecific gain-setting mechanism, scaling the output of a neuron. However, the interhemispheric input also changed the contrast sensitivity of many neurons, thereby acting on the input. Such a contrast gain mechanism has important implications because it extends the role of the lateral network from pure response amplification to the modulation of a specific feature. Interestingly, for many neurons, we found a mixture of input and output gain modulation. Based on these findings and the known physiology of callosal connections in the visual system, we developed a simple model of lateral interhemispheric interactions. We conclude that the lateral network can act directly on its target, leading to a sensitivity change of a specific feature, while at the same time it also can act indirectly, leading to an unspecific gain setting. The relative contribution of these direct and indirect network effects determines the outcome for a particular neuron.
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9
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Arcaro MJ, Honey CJ, Mruczek REB, Kastner S, Hasson U. Widespread correlation patterns of fMRI signal across visual cortex reflect eccentricity organization. eLife 2015; 4. [PMID: 25695154 PMCID: PMC4337732 DOI: 10.7554/elife.03952] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 01/21/2015] [Indexed: 01/13/2023] Open
Abstract
The human visual system can be divided into over two-dozen distinct areas, each of which contains a topographic map of the visual field. A fundamental question in vision neuroscience is how the visual system integrates information from the environment across different areas. Using neuroimaging, we investigated the spatial pattern of correlated BOLD signal across eight visual areas on data collected during rest conditions and during naturalistic movie viewing. The correlation pattern between areas reflected the underlying receptive field organization with higher correlations between cortical sites containing overlapping representations of visual space. In addition, the correlation pattern reflected the underlying widespread eccentricity organization of visual cortex, in which the highest correlations were observed for cortical sites with iso-eccentricity representations including regions with non-overlapping representations of visual space. This eccentricity-based correlation pattern appears to be part of an intrinsic functional architecture that supports the integration of information across functionally specialized visual areas. DOI:http://dx.doi.org/10.7554/eLife.03952.001 Imagine you are looking out over a scenic landscape. The image you perceive is actually made up of many different visual components—for example color and movement—that are processed across many different areas in a region of the brain called the visual cortex. An important question for neuroscience is how the visual system combines information from so many different areas to create a coherent picture of the world around us. Many areas of the visual cortex have their own map of what we see (the visual field). These maps allow the brain to maintain its representation of the visual field as the information passes from one processing area to the next. Areas that process corresponding parts of the visual field are physically interconnected, and tend to be active at the same time, which suggests that they are working together in some way. In addition, areas of the visual cortex that process different sections of the visual field can be activated at the same time, but it is not clear how this works. Here, Arcaro et al. used a technique called functional magnetic resonance imaging (fMRI) to image the brains of people as they watched movies and while they rested. The images showed that seemingly unrelated areas of the visual cortex respond in similar ways if they are processing sections of the visual field that are the same distance from the center of the person's gaze. For example, if you look directly at the center of a computer screen parts of the brain that process the top of the screen are active at the same time as parts that process the bottom. Arcaro et al.'s findings suggest that the brain uses the distance from the center of our gaze to bring together information from different areas of the visual cortex. This offers a new insight into how the brain assembles the many pieces of the visual jigsaw to make a complete picture. Future work will investigate how the architecture of the visual cortex is able to support this coupling of different areas, and how it might influence our perception of the visual world. DOI:http://dx.doi.org/10.7554/eLife.03952.002
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Affiliation(s)
- Michael J Arcaro
- Princeton Neuroscience Institute, Princeton University, Princeton, United States
| | | | - Ryan E B Mruczek
- Department of Psychology, Worcester State University, Worcester, United States
| | - Sabine Kastner
- Princeton Neuroscience Institute, Princeton University, Princeton, United States
| | - Uri Hasson
- Princeton Neuroscience Institute, Princeton University, Princeton, United States
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10
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Butt OH, Benson NC, Datta R, Aguirre GK. Hierarchical and homotopic correlations of spontaneous neural activity within the visual cortex of the sighted and blind. Front Hum Neurosci 2015; 9:25. [PMID: 25713519 PMCID: PMC4322716 DOI: 10.3389/fnhum.2015.00025] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 01/12/2015] [Indexed: 10/31/2022] Open
Abstract
Spontaneous neural activity within visual cortex is synchronized by both monosynaptic, hierarchical connections between visual areas and indirect, network-level activity. We examined the interplay of hierarchical and network connectivity in human visual cortex by measuring the organization of spontaneous neural signals within the visual cortex in total darkness using functional magnetic resonance imaging (fMRI). Twenty-five blind (14 congenital and 11 postnatal) participants with equally severe vision loss and 22 sighted subjects were studied. An anatomical template based on cortical surface topology was used for all subjects to identify the quarter-field components of visual areas V1-V3, and assign retinotopic organization. Cortical visual areas that represent the same quadrant of the visual field were considered to have a hierarchical relationship, while the spatially separated quarters of the same visual area were considered homotopic. Blindness was found to enhance correlations between hierarchical cortical areas as compared to indirect, homotopic areas at both the level of visual areas (p = 0.000031) and fine, retinotopic scale (p = 0.0024). A specific effect of congenital, but not postnatal, blindness was to further broaden the cortico-cortico connections between hierarchical visual areas (p = 0.0029). This finding is consistent with animal studies that observe a broadening of axonal terminal arborization when the visual cortex is deprived of early input. We therefore find separable roles for vision in developing and maintaining the intrinsic neural activity of visual cortex.
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Affiliation(s)
- Omar H Butt
- Department of Neurology, University of Pennsylvania Philadelphia, PA, USA
| | - Noah C Benson
- Department of Neurology, University of Pennsylvania Philadelphia, PA, USA ; Department of Psychology, University of Pennsylvania Philadelphia, PA, USA
| | - Ritobrato Datta
- Department of Neurology, University of Pennsylvania Philadelphia, PA, USA
| | - Geoffrey K Aguirre
- Department of Neurology, University of Pennsylvania Philadelphia, PA, USA
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11
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ARCARO M, KASTNER S. Topographic organization of areas V3 and V4 and its relation to supra-areal organization of the primate visual system. Vis Neurosci 2015; 32:E014. [PMID: 26241035 PMCID: PMC4900470 DOI: 10.1017/s0952523815000115] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Areas V3 and V4 are commonly thought of as individual entities in the primate visual system, based on definition criteria such as their representation of visual space, connectivity, functional response properties, and relative anatomical location in cortex. Yet, large-scale functional and anatomical organization patterns not only emphasize distinctions within each area, but also links across visual cortex. Specifically, the visuotopic organization of V3 and V4 appears to be part of a larger, supra-areal organization, clustering these areas with early visual areas V1 and V2. In addition, connectivity patterns across visual cortex appear to vary within these areas as a function of their supra-areal eccentricity organization. This complicates the traditional view of these regions as individual functional "areas." Here, we will review the criteria for defining areas V3 and V4 and will discuss functional and anatomical studies in humans and monkeys that emphasize the integration of individual visual areas into broad, supra-areal clusters that work in concert for a common computational goal. Specifically, we propose that the visuotopic organization of V3 and V4, which provides the criteria for differentiating these areas, also unifies these areas into the supra-areal organization of early visual cortex. We propose that V3 and V4 play a critical role in this supra-areal organization by filtering information about the visual environment along parallel pathways across higher-order cortex.
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Affiliation(s)
- M.J. ARCARO
- Princeton Neuroscience Institute, Princeton University, Princeton, New Jersey 08544
- Department of Psychology, Princeton University, Princeton, New Jersey 08544
| | - S. KASTNER
- Princeton Neuroscience Institute, Princeton University, Princeton, New Jersey 08544
- Department of Psychology, Princeton University, Princeton, New Jersey 08544
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12
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Cerkevich CM, Collins CE, Kaas JH. Cortical inputs to the middle temporal visual area in New World owl monkeys. Eye Brain 2014; 2015:1-15. [PMID: 25620872 PMCID: PMC4302954 DOI: 10.2147/eb.s69713] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
We made eight retrograde tracer injections into the middle temporal visual area (MT) of three New World owl monkeys (Aotus nancymaae). These injections were placed across the representation of the retina in MT to allow us to compare the locations of labeled cells in other areas in order to provide evidence for any retinotopic organization in those areas. Four regions projected to MT: 1) early visual areas, including V1, V2, V3, the dorsolateral visual area, and the dorsomedial visual area, provided topographically organized inputs to MT; 2) all areas in the MT complex (the middle temporal crescent, the middle superior temporal area, and the fundal areas of the superior temporal sulcus) projected to MT. Somewhat variably across injections, neurons were labeled in other parts of the temporal lobe; 3) regions in the location of the medial visual area, the posterior parietal cortex, and the lateral sulcus provided other inputs to MT; 4) finally, projections from the frontal eye field, frontal visual field, and prefrontal cortex were also labeled by our injections. These results further establish the sources of input to MT, and provide direct evidence within and across cases for retinotopic patterns of projections from early visual areas to MT.
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Affiliation(s)
- Christina M Cerkevich
- Center for the Neural Basis of Cognition and Systems Neuroscience Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | | | - Jon H Kaas
- Department of Psychology, Vanderbilt University, Nashville, TN, USA
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13
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Solomon SG, Rosa MGP. A simpler primate brain: the visual system of the marmoset monkey. Front Neural Circuits 2014; 8:96. [PMID: 25152716 PMCID: PMC4126041 DOI: 10.3389/fncir.2014.00096] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 07/22/2014] [Indexed: 12/15/2022] Open
Abstract
Humans are diurnal primates with high visual acuity at the center of gaze. Although primates share many similarities in the organization of their visual centers with other mammals, and even other species of vertebrates, their visual pathways also show unique features, particularly with respect to the organization of the cerebral cortex. Therefore, in order to understand some aspects of human visual function, we need to study non-human primate brains. Which species is the most appropriate model? Macaque monkeys, the most widely used non-human primates, are not an optimal choice in many practical respects. For example, much of the macaque cerebral cortex is buried within sulci, and is therefore inaccessible to many imaging techniques, and the postnatal development and lifespan of macaques are prohibitively long for many studies of brain maturation, plasticity, and aging. In these and several other respects the marmoset, a small New World monkey, represents a more appropriate choice. Here we review the visual pathways of the marmoset, highlighting recent work that brings these advantages into focus, and identify where additional work needs to be done to link marmoset brain organization to that of macaques and humans. We will argue that the marmoset monkey provides a good subject for studies of a complex visual system, which will likely allow an important bridge linking experiments in animal models to humans.
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Affiliation(s)
- Samuel G Solomon
- Department of Experimental Psychology, University College London London, UK
| | - Marcello G P Rosa
- Department of Physiology, Monash University, Clayton, VIC Australia ; Monash Vision Group, Monash University, Clayton, VIC Australia ; Australian Research Council Centre of Excellence for Integrative Brain Function, Monash University Node, Clayton, VIC Australia
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14
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Abstract
In the primate visual cortex, areas V1 and V2 distribute information they receive from the retina to virtually all extrastriate cortex, parsing this information into dorsal and ventral streams. Therefore, understanding the connectivity between V1 and V2 is crucial to understand visual cortical processing. Cytochrome oxidase staining in V2 reveals a repeating pattern of pale-thick-pale-thin stripes. V1 sends parallel output pathways to distinct V2 stripes. Previous models proposed either three or two parallel V1-to-V2 pathways in macaque, but both models viewed the two pale stripes within a single stripe cycle as a single compartment. However, recent studies have suggested that the two pale stripes may be functionally distinct, and in marmosets they also differ anatomically in the laminar origin of projections they receive from V1. Here we have asked whether the two pale stripes are also anatomically distinct in macaque. We made small retrograde tracer injections in different pale stripe types. We found that while both pale stripes receive a predominant V1 input from layers 2/3, only one set of pale stripes (pale lateral) receives significant projections from layer 4B, while the other set (pale medial) receives few or no layer 4B projections. Moreover, different tracer injections in nearby pale stripe types revealed that 97-99% of layer 2/3 cells only project to a single pale stripe type. These results demonstrate that in macaque, the two pale stripes are anatomically distinct compartments, and support the notion of two distinct projection streams from V1 to the two pale stripes of V2.
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15
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Chaplin TA, Yu HH, Rosa MGP. Representation of the visual field in the primary visual area of the marmoset monkey: magnification factors, point-image size, and proportionality to retinal ganglion cell density. J Comp Neurol 2013; 521:1001-19. [PMID: 22911425 DOI: 10.1002/cne.23215] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Revised: 07/25/2012] [Accepted: 08/14/2012] [Indexed: 11/11/2022]
Abstract
The primary visual area (V1) forms a systematic map of the visual field, in which adjacent cell clusters represent adjacent points of visual space. A precise quantification of this map is key to understanding the anatomical relationships between neurons located in different stations of the visual pathway, as well as the neural bases of visual performance in different regions of the visual field. We used computational methods to quantify the visual topography of V1 in the marmoset (Callithrix jacchus), a small diurnal monkey. The receptive fields of neurons throughout V1 were mapped in two anesthetized animals using electrophysiological recordings. Following histological reconstruction, precise 3D reconstructions of the V1 surface and recording sites were generated. We found that the areal magnification factor (M(A) ) decreases with eccentricity following a function that has the same slope as that observed in larger diurnal primates, including macaque, squirrel, and capuchin monkeys, and humans. However, there was no systematic relationship between M(A) and polar angle. Despite individual variation in the shape of V1, the relationship between M(A) and eccentricity was preserved across cases. Comparison between V1 and the retinal ganglion cell density demonstrated preferential magnification of central space in the cortex. The size of the cortical compartment activated by a punctiform stimulus decreased from the foveal representation towards the peripheral representation. Nonetheless, the relationship between the receptive field sizes of V1 cells and the density of ganglion cells suggested that each V1 cell receives information from a similar number of retinal neurons, throughout the visual field.
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Affiliation(s)
- Tristan A Chaplin
- Department of Physiology, Monash University, Clayton, VIC 3800, Australia
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16
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Jeffs J, Federer F, Ichida JM, Angelucci A. High-resolution mapping of anatomical connections in marmoset extrastriate cortex reveals a complete representation of the visual field bordering dorsal V2. Cereb Cortex 2013; 23:1126-47. [PMID: 22523183 PMCID: PMC3615347 DOI: 10.1093/cercor/bhs088] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The primate visual cortex consists of many areas. The posterior areas (V1, V2, V3, and middle temporal) are thought to be common to all primate species. However, the organization of cortex immediately anterior to area V2 (the "third tier" cortex) remains controversial, particularly in New World primates. The main point of contention has been whether the third tier cortex consists of a single area V3, representing lower and upper visual quadrants in dorsal and ventral cortex, respectively, or of 2 distinct areas (the dorsomedial [DM] area and a V3-like area). Resolving this controversy is crucial to understand the function and evolution of the third tier cortex. We have addressed this issue in marmosets, by performing high-precision mapping of corticocortical connections in cortex bordering dorsal V2. Multiple closely spaced neuroanatomical tracer injections were placed across the full width of dorsal V2 or adjacent anterior cortex, and the location of resulting labeled cells mapped throughout whole flattened visual cortex. The resulting topographic patterns of labeled connections allowed us to define areas and their boundaries. We found that a complete representation of the visual field borders dorsal V2 and that the third tier cortex consists of 2 distinct areas. These results unequivocally support the DM model.
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Affiliation(s)
- Janelle Jeffs
- Department of Ophthalmology, Moran Eye Center
- Department of Bioengineering
| | - Frederick Federer
- Department of Ophthalmology, Moran Eye Center
- Neuroscience Program, University of Utah, Salt Lake City, UT 84132, USA
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17
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Wei H, Lang B, Zuo Q. Contour detection model with multi-scale integration based on non-classical receptive field. Neurocomputing 2013. [DOI: 10.1016/j.neucom.2012.09.027] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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18
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Lyon DC. The case for a dorsal V3 in the ‘third-tier’ of primate visual cortex: a reply to ‘the case for a dorsomedial area in the primate ‘third-tier’ visual cortex’. Proc Biol Sci 2013. [DOI: 10.1098/rspb.2012.1994] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- David C. Lyon
- Department of Anatomy and Neurobiology, School of Medicine, University of California, Irvine, CA 92617, USA
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Bock NA, Hashim E, Kocharyan A, Silva AC. Visualizing myeloarchitecture with magnetic resonance imaging in primates. Ann N Y Acad Sci 2011; 1225 Suppl 1:E171-81. [PMID: 21599695 DOI: 10.1111/j.1749-6632.2011.06000.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The pattern of myelination over the cerebral cortex, termed myeloarchitecture, is an established and often-used feature to visualize cortical organization with histology in a variety of primate species. In this paper, we use in vivo magnetic resonance imaging (MRI) and advanced image processing using surface rendering to visualize and characterize myeloarchitecture in a small nonhuman primate, the common marmoset (Callithrix jacchus). Through images made in four female adult marmosets, we produce a representative 3D map of marmoset myeloarchitecture and flatten and annotate this map to show the location and extent of a variety of major areas of the cortex, including the primary visual, auditory, and somatosensory areas. By treating our MRI data as a surface, we can measure the surface area of cortical areas, and we present these measurements here to summarize cortical organization in the marmoset.
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Affiliation(s)
- Nicholas A Bock
- Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario, Canada.
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20
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Ahmed B, Cordery PM, McLelland D, Bair W, Krug K. Long-range clustered connections within extrastriate visual area V5/MT of the rhesus macaque. ACTA ACUST UNITED AC 2011; 22:60-73. [PMID: 21571693 DOI: 10.1093/cercor/bhr072] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Visual area V5/MT in the rhesus macaque has a distinct functional organization, where neurons with specific preferences for direction of motion and binocular disparity are co-organized in columns or clusters. Here, we analyze the pattern of intrinsic connectivity within cortical area V5/MT in both parasagittal sections of the intact brain and tangential sections from flatmounted cortex using small injections of the retrograde tracer cholera toxin subunit b. Labeled cells were predominantly found in cortical layers 2, 3, and 6. Going along the cortical layers, labeled cells were concentrated in regularly spaced clusters. The clusters nearest to the injection site were approximately 2 mm from its center. In flatmounted cortex, along the dorsoventral axis of V5/MT, we identified further clusters of labeled cells up to 10 mm from the injection site. Quantitative analysis of parasagittal sections estimated average cluster spacing at 2.2 mm; in cortical flatmounts, spacing was 2.3 mm measured radially from the injection site. The results suggest a regular pattern of intrinsic connectivity within V5/MT, which is consistent with connectivity between sites with a common preference for both direction of motion and binocular depth. The long-range connections can potentially account for the large suppressive surrounds of V5/MT neurons.
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Affiliation(s)
- Bashir Ahmed
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK
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21
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Analysis of the context integration mechanisms underlying figure-ground organization in the visual cortex. J Neurosci 2010; 30:6482-96. [PMID: 20463212 DOI: 10.1523/jneurosci.5168-09.2010] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Most neurons in visual cortex respond to contrast borders and are orientation selective, and some are also selective for which side of a border is figure and which side is ground ("border ownership coding"). These neurons are influenced by the image context far beyond the classical receptive field (CRF) and as early as 25 ms after the onset of activity in the cortex. The nature of the fast context integration mechanism is not well understood. What parts of a figure contribute to the context effect? What is the structure of the "extraclassical surround"? Is the context information propagated through horizontal fibers within cortex or through reciprocal connections via higher-level areas? To address these questions, we studied border ownership modulation with fragmented figures. Neurons were recorded in areas V1 and V2 of Macaca mulatta under behaviorally induced fixation. Test figures were fragmented rectangles. While one edge was centered on the CRF, the presence of the fragments outside the CRF was varied. The surround fragments produced facilitation on the preferred border ownership side as well as suppression on the nonpreferred side, with approximately 80% of the locations contributing on average. Fragments far from the CRF influenced the responses even in the absence of fragments closer to the CRF, and without the extra delay that would incur from propagation through horizontal fibers. Three principally different models are discussed. The results support a model in which the antagonistic surround influences are produced by reentrant signals from a higher-level area.
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22
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Abstract
In the primate visual system, areas V1 and V2 distribute information they receive from the retina to all higher cortical areas, sorting this information into dorsal and ventral streams. Therefore, knowledge of the organization of projections between V1 and V2 is crucial to understand how the cortex processes visual information. In primates, parallel output pathways from V1 project to distinct V2 stripes. The traditional tripartite division of V1-to-V2 projections was recently replaced by a bipartite scheme, in which thin stripes receive V1 inputs from blob columns, and thick and pale stripes receive common input from interblob columns. Here, we demonstrate that thick and pale stripes, instead, receive spatially segregated V1 inputs and that the interblob is partitioned into two compartments: the middle of the interblob projecting to pale stripes and the blob/interblob border region projecting to thick stripes. Double-labeling experiments further demonstrate that V1 cells project to either thick or pale stripes, but rarely to both. We also find laminar specialization of V1 outputs, with layer 4B contributing projections mainly to thick stripes, and no projections to one set of pale stripes. These laminar differences suggest different contribution of magno, parvo, and konio inputs to each V1 output pathway. These results provide a new foundation for parallel processing models of the visual system by demonstrating four V1-to-V2 pathways: blob columns-to-thin stripes, blob/interblob border columns-to-thick stripes, interblob columns-to-pale(lateral) stripes, layer 2/3-4A interblobs-to-pale(medial) stripes.
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23
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Bock NA, Kocharyan A, Liu JV, Silva AC. Visualizing the entire cortical myelination pattern in marmosets with magnetic resonance imaging. J Neurosci Methods 2009; 185:15-22. [PMID: 19737577 PMCID: PMC2783340 DOI: 10.1016/j.jneumeth.2009.08.022] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2009] [Revised: 08/27/2009] [Accepted: 08/31/2009] [Indexed: 11/27/2022]
Abstract
Myeloarchitecture, the pattern of myelin density across the cerebral cortex, has long been visualized in histological sections to identify distinct anatomical areas of the cortex. In humans, two-dimensional (2D) magnetic resonance imaging (MRI) has been used to visualize myeloarchitecture in select areas of the cortex, such as the stripe of Gennari in the primary visual cortex and Heschl's gyrus in the primary auditory cortex. Here, we investigated the use of MRI contrast based on longitudinal relaxation time (T(1)) to visualize myeloarchitecture in vivo over the entire cortex of the common marmoset (Callithrix jacchus), a small non-human primate that is becoming increasingly important in neuroscience and neurobiology research. Using quantitative T(1) mapping, we found that T(1) at 7T in a cortical region with a high myelin content was 15% shorter than T(1) in a region with a low myelin content. To maximize this T(1) contrast for imaging cortical myelination patterns, we optimized a magnetization-prepared rapidly acquired gradient echo (MP-RAGE) sequence. In whole-brain, 3D T(1)-weighted images made in vivo with the sequence, we identified six major cortical areas with high myelination and confirmed the results with histological sections stained for myelin. We also identified several subtle features of myeloarchitecture, showing the sensitivity of our technique. The ability to image myeloarchitecture over the entire cortex may prove useful in studies of longitudinal changes of the topography of the cortex associated with development and neuronal plasticity, as well as for guiding and confirming the location of functional measurements.
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Affiliation(s)
- Nicholas A. Bock
- Cerebral Microcirculation Unit/ Laboratory of Functional and Molecular Imaging/ National Institute of Neurological Disorders and Stroke/ National Institutes of Health, Bethesda, Maryland, United States
- Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Ara Kocharyan
- Cerebral Microcirculation Unit/ Laboratory of Functional and Molecular Imaging/ National Institute of Neurological Disorders and Stroke/ National Institutes of Health, Bethesda, Maryland, United States
| | - Junjie V. Liu
- Cerebral Microcirculation Unit/ Laboratory of Functional and Molecular Imaging/ National Institute of Neurological Disorders and Stroke/ National Institutes of Health, Bethesda, Maryland, United States
| | - Afonso C. Silva
- Cerebral Microcirculation Unit/ Laboratory of Functional and Molecular Imaging/ National Institute of Neurological Disorders and Stroke/ National Institutes of Health, Bethesda, Maryland, United States
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Abstract
In humans and other Old World primates, much of visual cortex comprises a set of retinotopic maps, embedded in a cortical sheet with well known, identifiable folding patterns. However, the relationship between these two prominent cortical variables has not been comprehensively studied. Here, we quantitatively tested this relationship using functional and structural magnetic resonance imaging in monkeys and humans. We found that the vertical meridian of the visual field tends to be represented on gyri (convex folds), whereas the horizontal meridian is preferentially represented in sulci (concave folds), throughout visual cortex in both primate species. This relationship suggests that the retinotopic maps may constrain the pattern of cortical folding during development.
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Connections of the dorsomedial visual area: pathways for early integration of dorsal and ventral streams in extrastriate cortex. J Neurosci 2009; 29:4548-63. [PMID: 19357280 DOI: 10.1523/jneurosci.0529-09.2009] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The dorsomedial area (DM), a subdivision of extrastriate cortex characterized by heavy myelination and relative emphasis on peripheral vision, remains the least understood of the main targets of striate cortex (V1) projections in primates. Here we placed retrograde tracer injections encompassing the full extent of this area in marmoset monkeys, and performed quantitative analyses of the numerical strengths and laminar patterns of its afferent connections. We found that feedforward projections from V1 and from the second visual area (V2) account for over half of the inputs to DM, and that the vast majority of the remaining connections come from other topographically organized visual cortices. Extrastriate projections to DM originate in approximately equal proportions from adjacent medial occipitoparietal areas, from the superior temporal motion-sensitive complex centered on the middle temporal area (MT), and from ventral stream-associated areas. Feedback from the posterior parietal cortex and other association areas accounts for <10% of the connections. These results do not support the hypothesis that DM is specifically associated with a medial subcircuit of the dorsal stream, important for visuomotor integration. Instead, they suggest an early-stage visual-processing node capable of contributing across cortical streams, much as V1 and V2 do. Thus, although DM may be important for providing visual inputs for guided body movements (which often depend on information contained in peripheral vision), this area is also likely to participate in other functions that require integration across wide expanses of visual space, such as perception of self-motion and contour completion.
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