Cortical Connections of Area V4 in the Macaque

Laboratory of Brain and Cognition, National Institute of Mental Health, National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892-1366, USA.
Cerebral Cortex (Impact Factor: 8.67). 04/2008; 18(3):477-99. DOI: 10.1093/cercor/bhm061
Source: PubMed


To determine the locus, full extent, and topographic organization of cortical connections of area V4 (visual area 4), we injected anterograde and retrograde tracers under electrophysiological guidance into 21 sites in 9 macaques. Injection sites included representations ranging from central to far peripheral eccentricities in the upper and lower fields. Our results indicated that all parts of V4 are connected with occipital areas V2 (visual area 2), V3 (visual area 3), and V3A (visual complex V3, part A), superior temporal areas V4t (V4 transition zone), MT (medial temporal area), and FST (fundus of the superior temporal sulcus [STS] area), inferior temporal areas TEO (cytoarchitectonic area TEO in posterior inferior temporal cortex) and TE (cytoarchitectonic area TE in anterior temporal cortex), and the frontal eye field (FEF). By contrast, mainly peripheral field representations of V4 are connected with occipitoparietal areas DP (dorsal prelunate area), VIP (ventral intraparietal area), LIP (lateral intraparietal area), PIP (posterior intraparietal area), parieto-occipital area, and MST (medial STS area), and parahippocampal area TF (cytoarchitectonic area TF on the parahippocampal gyrus). Based on the distribution of labeled cells and terminals, projections from V4 to V2 and V3 are feedback, those to V3A, V4t, MT, DP, VIP, PIP, and FEF are the intermediate type, and those to FST, MST, LIP, TEO, TE, and TF are feedforward. Peripheral field projections from V4 to parietal areas could provide a direct route for rapid activation of circuits serving spatial vision and spatial attention. By contrast, the predominance of central field projections from V4 to inferior temporal areas is consistent with the need for detailed form analysis for object vision.

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Available from: Ricardo Gattass, Oct 09, 2015
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    • "Neural responses were much the same, despite whether the figure was defined by luminance contrast or moving dots, which indicates a cue-invariant figure response (Mysore et al., 2006). V4 cells receive their main feedforward input from and send feedback to V1 and V2 (Ungerleider et al., 2008). The input from V1 comes from cells that represent the foveal portion of the visual field in both cytochrome oxidase blob and interblob regions (Nakamura et al., 1993). "
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    ABSTRACT: Camouflaged animals that have very similar textures to their surroundings are difficult to detect when stationary. However, when an animal moves, humans readily see a figure at a different depth than the background. How do humans perceive a figure breaking camouflage, even though the texture of the figure and its background may be statistically identical in luminance? We present a model that demonstrates how the primate visual system performs figure–ground segregation in extreme cases of breaking camouflage based on motion alone. Border-ownership signals develop as an emergent property in model V2 units whose receptive fields are nearby kinetically defined borders that separate the figure and background. Model simulations support border-ownership as a general mechanism by which the visual system performs figure–ground segregation, despite whether figure–ground boundaries are defined by luminance or motion contrast. The gradient of motion- and luminance-related border-ownership signals explains the perceived depth ordering of the foreground and background surfaces. Our model predicts that V2 neurons, which are sensitive to kinetic edges, are selective to border-ownership (magnocellular B cells). A distinct population of model V2 neurons is selective to border-ownership in figures defined by luminance contrast (parvocellular B cells). B cells in model V2 receive feedback from neurons in V4 and MT with larger receptive fields to bias border-ownership signals toward the figure. We predict that neurons in V4 and MT sensitive to kinetically defined figures play a crucial role in determining whether the foreground surface accretes, deletes, or produces a shearing motion with respect to the background.
    Vision Research 11/2014; 106. DOI:10.1016/j.visres.2014.11.002 · 1.82 Impact Factor
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    • "The goal of this study was not only to establish whether V4 neurons were able to signal the sudden appearance of a shape within a noise stimulus, but also to determine if this information could directly contribute to behavior. Area V4 is reciprocally connected to prefrontal and parietal areas (Ungerleider et al., 2008; Ninomiya et al., 2012) that have been shown to accumulate evidence for decisions in sensory-based tasks (Shadlen and Newsome, 2001; Ding and Gold, 2012). In the context of extremely rapid visual decisions, it has also been suggested that V4 may directly initiate saccadic decisions (Kirchner and Thorpe, 2006). "
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    ABSTRACT: Vision in foveate animals is an active process that requires rapid and constant decision-making. For example, when a new object appears in the visual field, we can quickly decide to inspect it by directing our eyes to the object's location. We studied the contribution of primate area V4 to these types of rapid foveation decisions. Animals performed a reaction time task that required them to report when any shape appeared within a peripherally-located noisy stimulus by making a saccade to the stimulus location. We found that about half of the randomly sampled V4 neurons not only rapidly and precisely represented the appearance of this shape, but they were also predictive of the animal's saccades. A neuron's ability to predict the animal's saccades was not related to the specificity with which the cell represented a single type of shape but rather to its ability to signal whether any shape was present. This relationship between sensory sensitivity and behavioral predictiveness was not due to global effects such as alertness, as it was equally likely to be observed for cells with increases and decreases in firing rate. Careful analysis of the timescales of reliability in these neurons implies that they reflect both feedforward and feedback shape detecting processes. In approximately 7% of our recorded sample, individual neurons were able to predict both the delay and precision of the animal's shape detection performance. This suggests that a subset of V4 neurons may have been directly and causally contributing to task performance and that area V4 likely plays a critical role in guiding rapid, form-based foveation decisions.
    Frontiers in Neuroscience 09/2014; 8:294. DOI:10.3389/fnins.2014.00294 · 3.66 Impact Factor
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    • "Since fMRI became available (Dubowitz et al., 1998; Logothetis et al., 1998; Stefanacci et al., 1998; Vanduffel et al., 1998) for systematic investigation in the alert monkey (Vanduffel et al., 2001), considerable progress has been made, through fMRIguided monkey single-cell studies, and by parallel comparative imaging in humans and monkeys. In addition, the connections of TE cortex have recently been reassessed (Saleem et al., 2007, 2008; Ungerleider et al., 2008; Gerbella et al., 2010; Kravitz et al., 2013), allowing a tight comparison between anatomical connectivity and functionality. "
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    ABSTRACT: We propose that the ventral visual pathway of human and non-human primates is organized into three levels: (1) ventral retinotopic cortex including what is known as TEO in the monkey but corresponds to V4A and PITd/v, and the phPIT cluster in humans, (2) area TE in the monkey and its homolog LOC and neighboring fusiform regions, and more speculatively, (3) TGv in the monkey and its possible human equivalent, the temporal pole. We attribute to these levels the visual representations of features, partial real-world entities (RWEs), and known, complete RWEs, respectively. Furthermore, we propose that the middle level, TE and its homolog, is organized into three parallel substreams, lower bank STS, dorsal convexity of TE, and ventral convexity of TE, as are their corresponding human regions. These presumably process shape in depth, 2D shape and material properties, respectively, to construct RWE representations.
    Frontiers in Psychology 07/2014; 5:695. DOI:10.3389/fpsyg.2014.00695 · 2.80 Impact Factor
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