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Recurrent V1-V2 interaction in early visual boundary processing

BIOLOGICAL CYBERNETICS 1999年第5-6期81卷 425-444页

作者： Neumann, H Sepp, W Univ Ulm Abt Neuroinformat D-89069 Ulm Germany

A majority of cortical areas are connected via feedforward and feedback fiber projections. In feedforward pathways we mainly observe stages of feature detection and integration. The computational role of the descending pathways at different stages of processing remains mainly unknown. Based on empirical findings we suggest that the top-down feedback pathways subserve a context-dependent gain control mechanism. We propose a new computational model for recurrent contour processing in which normalized activities of orientation selective contrast cells are fed forward to the next processing stage. There, the arrangement of input activation is matched against local patterns of contour shape. The resulting activities are subsequently fed back to the previous stage to locally enhance those initial measurements that are consistent with the top-down generated responses. In all, we suggest a computational theory for recurrent processing in the visual cortex in which the significance of local measurements is evaluated on the basis of a broader visual context that is represented in terms of contour code patterns. The model serves as a framework to link physiological with perceptual data gathered in psychophysical experiments. It handles a variety of perceptual phenomena, such as the local grouping of fragmented shape outline, texture surround and density effects, and the interpolation of illusory contours.

关键词：控制论反馈模型神经学光刺激视皮质/解剖学和组织学视皮质/生理学视通路/生理学视知觉/生理学动物人类

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A neural model of motion processing and visual navigation by cortical area MST

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CEREBRAL CORTEX 1999年第8期9卷 878-895页

作者： Grossberg, S Mingolla, E Pack, C Boston Univ Dept Cognit & Neural Syst Boston MA 02215 USA Boston Univ Ctr Adapt Syst Boston MA 02215 USA

Cells in the dorsal medial superior temporal cortex (MSTd) process optic flow generated by self-motion during visually guided navigation. A neural model shows how interactions between well-known neural mechanisms (log polar cortical magnification, Gaussian motion-sensitive receptive fields, spatial pooling of motion-sensitive signals and subtractive extraretinal eye movement signals) lead to emergent properties that quantitatively simulate neurophysiological data about MSTd cell properties and psychophysical data about human navigation. Model cells match MSTd neuron responses to optic flow stimuli placed in different parts of the visual field, including position invariance, tuning curves, preferred spiral directions, direction reversals, average response curves and preferred locations for stimulus motion centers. The model shows how the preferred motion direction of the most active MSTd cells can explain human judgments of self-motion direction (heading), without using complex heading templates. The model explains when extraretinal eye movement signals are needed for accurate heading perception, and when retinal input is sufficient, and how heading judgments depend on scene layouts and rotation rates.

关键词：算法眼球运动/生理学模型神经学视网膜/解剖学和组织学视网膜/生理学颞叶/解剖学和组织学颞叶/生理学视皮质/解剖学和组织学视皮质/生理学视通路/解剖学和组织学视通路/生理学人类

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SOME OBSERVATIONS ON PATTERNS OF SEGREGATED GENICULATE INPUTS TO VISUAL-CORTEX IN NEW WORLD PRIMATES - AUTORADIOGRAPIC STUDY

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BRAIN RESEARCH 1978年第2期159卷 371-378页

作者： ROWE, MH BENEVENTO, LA REZAK, M UNIV ILLINOIS MED CTRCOLL MEDDEPT ANATCHICAGOIL 60680

The authors have examined the pattern of LGN projections in the squirrel monkey and the owl monkey with transneuronal autoradiography in an attempt to determine how the organization of these projections is related to the organization of lower levels of the visual pathway: particularly how and to what extent segregation of various types of retinal afferents in the LGN is associated with segregation of LGN terminals in the visual cortex.

关键词：美洲枭猴放射自显影术半球优势大脑/生理学膝状体/解剖学和组织学类人猿亚目视网膜/解剖学和组织学松鼠猴属视皮质/解剖学和组织学视通路/解剖学和组织学动物

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PROJECTIONS FROM CORTEX TO TECTUM IN THE TREE SHREW, TUPAIA-GLIS

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JOURNAL OF COMPARATIVE NEUROLOGY 1979年第2期185卷 253-291页

作者： CASSEDAY, JH JONES, DR DIAMOND, IT DUKE UNIV DEPT SURG DURHAM NC 27710 USA DUKE UNIV DEPT PSYCHOL DURHAM NC 27710 USA

Sensory neocortex of the tree shrew was divided into 3 main areas: the visual field, the auditory field and the somatic field which includes motor cortex. Cortical cells which project to the tectum were identified by injecting HRP [horseradish peroxidase] into superficial or deep layers of the superior colliculus and into various parts of the inferior colliculus. These descending projections are well organized according to their origin in the 3 main sensory fields of the cortex. Auditory field: labeled cells are found only in the core or auditory koniocortex, after injections of HRP in the pericentral area of the inferior colliculus;labeled cells are found in auditory belt areas after injections in posterior parts of the intermediate and deep layers of the superior colliculus, adjacent to the inferior colliculus. Somatic field: labeled cells are also found in the somatic field after injections in the intermediate and deep layers of the superior colliculus, so that auditory and somatic fields probably overlap to some extent. The possibility that somatic koniocortex has an exclusive target in the intermediate or deep layers of the superior colliculus is not excluded. Visual field: labeled cells are found only in the core or striate cortex after injections in the superficial layers of the superior colliculus. Labeled cells are found in the visual belt after injections in the rostral parts of the intermediate layers of the superior colliculus. When these results are related to ascending sensory pathways a picture emerges of a series of circuits or loops which interconnect parallel sensory pathways. These loops eventually reach the deep layers of the superior colliculus which of course have indirect access to motor neurons.

关键词：听觉皮质/解剖学和组织学听觉通路/解剖学和组织学脑图脑干/解剖学和组织学大脑皮质/解剖学和组织学神经通路/解剖学和组织学原猴亚目/解剖学和组织学丘脑核/解剖学和组织学树鼩科/解剖学和组织学视皮质/解剖学和组织学视通路/解剖学和组织学动物

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PROJECTIONS TO VISUAL-CORTEX IN GOLDEN-HAMSTER

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JOURNAL OF COMPARATIVE NEUROLOGY 1979年第1期183卷 185-204页

作者： DURSTELER, MR BLAKEMORE, C GAREY, LJ UNIV LAUSANNE INST ANAT CH-1011 LAUSANNE SWITZERLAND

Retrograde transport of horseradish peroxidase (HRP) was used to determine the origins of afferent connexions to the visual cortex (areas 17, 18a and 18b) in the hamster. The distribution of neurons projecting to the visual cortex from other cortical areas, from the thalamus and from the brainstem was studied using a computer technique for three-dimensional reconstruction. There is a topographically organized projection from the dorsal lateral geniculate nucleus to area 17, but probably to no other of the areas studied. The lateral posterior nucleus of the thalamus (LP) projects to area 18a and weakly to area 17. The lateral nucleus (L) projects to area 18b and also, probably, weakly to area 17. The cortical projections from LP and L are also organized topographically but relatively grossly compared with the geniculo-cortical pathway. There are reciprocal association projections between area 17 and areas 18a and 18b. Areas 18a projects weakly to 18b. The main commissural connexions of the posterior neocortex are between the area 17/18a boundary zones in the two hemispheres, with little between the bodies of area 17. Labelled neurons were found bilaterally in the locus coeruleus, more ipsilaterally than contralaterally, after multiple injections into the visual cortex: single, small injections sometimes resulted in the labelling of a single cell body in the locus coeruleus.

关键词：脑图脑干/解剖学和组织学胼胝体/解剖学和组织学仓鼠亚科膝状体/解剖学和组织学类人猿亚目金仓鼠神经通路/解剖学和组织学种特异性丘脑核/解剖学和组织学视皮质/解剖学和组织学动物猫大鼠

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Retinotopy and color sensitivity in human visual cortical area V8

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NATURE NEUROSCIENCE 1998年第3期1卷 235-241页

作者： Hadjikhani, N Liu, AK Dale, AM Cavanagh, P Tootell, RBH Massachusetts Gen Hosp Nucl Magnet Resonance Ctr Charlestown MA 02129 USA

Prior studies suggest the presence of a color-selective area in the inferior occipital-temporal region of human visual cortex. It has been proposed that this human area is homologous to macaque area V4, which is arguably color selective, but this has never been tested directly. To test this model, we compared the location of the human color-selective region to the retinotopic area boundaries in the same subjects, using functional magnetic resonance imaging (fMRI), cortical flattening and retinotopic mapping techniques. The human color-selective region did not match the location of area V4 (neither its dorsal nor ventral subdivisions), as extrapolated from macaque maps. Instead this region coincides with a new retinotopic area that we call 'V8', which includes a distinct representation of the fovea and both upper and lower visual fields. We also tested the response to stimuli that produce color afterimages and found that these stimuli, like real colors, caused preferential activation of V8 but not V4.

关键词：后像/生理学脑图/方法色色觉/生理学中央凹/生理学光恒河猴/生理学磁共振成像光刺激/方法视皮质/解剖学和组织学视皮质/生理学视野/生理学动物人类

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Plasticity in adult cat visual cortex (area 17) following circumscribed monocular lesions of all retinal layers

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JOURNAL OF PHYSIOLOGY-LONDON 2000年第2期524卷 587-602页

作者： Calford, MB Wang, C Taglianetti, V Waleszczyk, WJ Burke, W Dreher, B Australian Natl Univ Psychobiol Lab Div Psychol Canberra ACT 0200 Australia Univ Queensland Vis Touch & Hearing Res Ctr Brisbane Qld 4072 Australia Univ Sydney Inst Biomed Res Dept Anat & Histol Sydney NSW 2006 Australia Univ Sydney Inst Biomed Res Dept Physiol Sydney NSW 2006 Australia M Nencki Inst Expt Biol PL-02093 Warsaw Poland

1. In eight adult cats intense, sharply circumscribed, monocular laser lesions were used to remove all cellular layers of the retina. The extents of the retinal lesions were subsequently confirmed with counts of cc-ganglion cells in retinal whole mounts;in some cases these revealed radial segmental degeneration of ganglion cells distal to the lesion. 2. Two to 24 weeks later, area 17 (striate cortex;V1) was studied electrophysiologically in a standard anaesthetized, paralysed (artificially respired) preparation. Recording single- or multineurone activity revealed extensive topographical reorganization within the lesion projection zone (LPZ). 3. Thus, with stimulation of the lesioned eye, about 75% of single neurones in the LPZ had 'ectopic' visual discharge fields which were displaced to normal retina in the immediate vicinity of the lesion. 4. The sizes of the ectopic discharge fields were not significantly different from the sizes of the normal discharge fields. Furthermore, binocular cells recorded from the LPZ, when stimulated via their ectopic receptive fields, exhibited orientation tuning and preferred stimulus velocities which were indistinguishable from those found when the cells were stimulated via the normal eye. 5. However, the responses to stimuli presented via ectopic discharge fields were generally weaker (lower peak discharge rates) than those to presentations via normal discharge fields, and were characterized by a lower-than-normal upper velocity limit. 6. Overall, the properties of the ectopic receptive fields indicate that cortical mechanisms rather than it retinal 'periphery' effect underlie the topographic reorganization of area 17 following monocular retinal lesions.

关键词：诱发电位视觉/生理学功能偏侧化/生理学神经元可塑性/生理学定向力/生理学光刺激视网膜/解剖学和组织学视网膜/细胞学视网膜/生理学视觉单眼/生理学视皮质/解剖学和组织学视皮质/细胞学视皮质/生理学视野/生理学视通路/细胞学视通路/生理学动物猫

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A new anatomical landmark for reliable identification of human area V5/MT: a quantitative analysis of sulcal patterning

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CEREBRAL CORTEX 2000年第5期10卷 454-463页

作者： Dumoulin, SO Bittar, RG Kabani, NJ Baker, CL Le Goualher, G Pike, GB Evans, AC McGill Univ Montreal Neurol Inst McConnell Brain Imaging Ctr Montreal PQ H3A 2B4 Canada Univ Utrecht Utrecht Netherlands McGill Univ Dept Ophthalmol McGill Vis Res Unit Montreal PQ H3A 2T5 Canada

The location of human area V5 (or MT) has been correlated with the intersection of the ascending limb of the inferior temporal sulcus (ALITS) and the lateral occipital sulcus (LO). This study was undertaken to attempt a replication and quantification of these observations using functional magnetic resonance imaging. V5 was significantly activated in 19 hemispheres with alternating, low contrast, random checkerboard patterns. We confirmed the stereotaxic location of V5 and were able to describe a fairly consistent sulcal pattern in the parieto-temporo-occipital cortex. V5 was usually (95%) buried within a sulcus, most commonly within the inferior temporal sulcus (ITS) (11%), the ascending limb of the ITS (ALITS) (53%) and the posterior continuation of the ITS (26%). The average distance from V5 of two identified anatomical landmarks of V5, the junctions of the LO and the ALITS, and the ITS and ALITS, were both similar to 1 cm. However, the LO-ALITS junction often had to be determined by interpolation (47%), and was not always present even with interpolation (21%). In contrast, the ITS-ALITS junction was always present and V5 was usually (90%) located in a sulcus intersecting with this junction, making it a more reliable landmark for localizing V5 with respect to gross morphological features on individual cortical surfaces.

关键词：解剖学/标准磁共振成像顶叶/解剖学和组织学顶叶/生理学光刺激可重复性结果颞叶/解剖学和组织学颞叶/生理学视皮质/解剖学和组织学视皮质/生理学成年人女(雌)性人类男(雄)性

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Localization of area prostriata and its projection to the cingulate motor cortex in the rhesus monkey

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CEREBRAL CORTEX 2000年第2期10卷 192-203页

作者： Morecraft, RJ Rockland, KS Van Hoesen, GW Univ S Dakota Sch Med Div Basic Biomed Sci Sect Neurol Sci Vermillion SD 57069 USA Univ Iowa Coll Med Dept Anat & Cell Biol Iowa City IA 52242 USA

Area prostriata is a poorly understood cortical area located in the anterior portion of the calcarine sulcus. It has attracted interest as a separate visual area and progenitor far the cortex of this modality. In this report we describe a direct projection from area prostriata to the rostral cingulate motor cortex (M3) that farms the fundus and lower bank of the anterior part of the cingulate sulcus. Injections of retrograde tracers in M3 resulted in labeled neurons in layers Ill, V and VI of prostriate cortex. However, injections of anterograde tracers in M3 did not demonstrate axon terminals in area prostriata. This connection was organized topographically such that the rostral part of M3 received input from the dorsal region of prostriate cortex, whereas middle and caudal levels of M3 received input from more ventral locations. Injections of retrograde and anterograde tracers in the caudal cingulate motor cortex (M4) did not produce labeling in prostriate cortex. Cytoarchitectural analysis confirmed the identity of area prostriata and further clarified its extent and borders with the parasubiculum of the hippocampal formation rostrally, and V1. of the visual cortex caudally. This linkage between cortex bordering V1 and cortex giving rise to a component of the corticofacial and corticospinal pathways demonstrates a more direct visuomotor route than visual association projections coursing laterally.

关键词：轴突运输扣带回/解剖学和组织学扣带回/生理学恒河猴/解剖学和组织学运动皮质/解剖学和组织学运动皮质/生理学神经通路/解剖学和组织学神经通路/生理学视皮质/解剖学和组织学视皮质/生理学动物

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COLUMNAR CORTICO-CORTICAL INTERCONNECTIONS WITHIN THE VISUAL-SYSTEM OF THE SQUIRREL AND MACAQUE MONKEYS

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BRAIN RESEARCH 1979年第2期162卷 201-217页

作者： WONGRILEY, M Dept. Anat. Univ. California San Francisco Calif. 94143

Cortico-cortical interconnections within the visual cortex of squirrel monkeys (Saimiri sciureus) were studied by single or multiple injections of [3H]leucine or combined [3H]leucine and horseradish peroxidase into the dorsolateral striate and prestriate cortices. Injections of [3H]leucine were also made into the dorsolateral striate cortex of a Macaca speciosa for comparison. In Saimiri the dorsolateral prestriate cortex is precisely and reciprocally connected with the striate and peristriate cortex, and with the posterior bank of the superior temporal sulcus, including the middle temporal area (MT). The dorsolateral striate area is precisely and reciprocally connected with the prestriate and MT area, but does not project to the perstriate cortex as in the case of the macaque. At each target site, the radioactively labeled terminal fields are distributed in a distinctly columnar fashion, with labeled columns (120-480 .mu.m in diameter, commonly 240 .mu.m) interdigitating with sparsely labeled or unlabeled columns of lesser widths. The HHP-labeled neurons invariably exist within the radioactively labeled columns. For all of the cortical areas examined except area 17, lamina IV is the principal receptive layer for associational fibers, while layers III and II, and V and VI within the same column, receive progressively less input. As for area 17, associational fibers from the prestriate cortex terminate mainly within lamina I, with laminae II, III, V and VI receiving decreasing amounts of input. The major visual cortical areas are interconnected in precise, topographical and reciprocal fashion. The columnar arrangement is the basis of both extra- and intercortical connections.

关键词：放射自显影术脑图半球优势大脑/生理学类人猿亚目猕猴属神经纤维/超微结构松鼠猴属颞叶/解剖学和组织学视皮质/解剖学和组织学视通路/解剖学和组织学动物男(雄)性

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