21 papers · ranked by Valyu relevance
Xiaochen Morning Liu, Paula Sanz‐Leon, P. A. Robinson
Neural field theory is used to quantitatively analyze the two-dimensional spatiotemporal correlation properties of gamma-band (30 – 70 Hz) oscillations evoked by stimuli arriving at the primary visual cortex (V1), and modulated by patchy connectivities that depend on orientation preference (OP). Correlation functions…
Mitchell Valdes-Sosa, Marlis Ontivero-Ortega, Jorge Iglesias-Fuster, Agustin Lage-Castellanos + 2 more
Using functional resonance imaging (fMRI), we studied the relationship between perceptual organization and network topology within the primary visual cortex (V1). Twenty-six humans (male and female) were recorded during active observation of two Global and two Local Navon letters. Correlations between fMRI fluctuations…
Davide Barbieri
The functional behavior of neurons in primary visual cortex can be partially modeled as a linear response to visual stimuli. This linear response can be formally described as a generalized wavelet analysis of images, intended as functions from R 2 to R + (we consider greyscale images), with respect to a family of…
Holly Bridge, Andrew Bell, Matt Ainsworth, Jerome Sallet + 7 more
Lesions of primate primary visual cortex (V1) lead to loss of conscious visual perception, and are often devastating to those affected. Understanding the neural consequences of such damage may aid the development of rehabilitation methods. In this rare case of a Rhesus macaque (monkey S), likely born without V1, we…
Li Zhaoping
Progress in vision research has been slower downstream than upstream of primary visual cortex (V1). Traditional frameworks have largely overlooked a central constraint: only a tiny fraction of retinal input is recognized. Thus, to a first approximation, vision is better formulated as looking and seeing through a…
Robert D. Rafal
In all vertebrates, visual signals from each visual field project to the opposite midbrain tectum (called the superior colliculus in mammals). The tectum/colliculus computes visual salience to select targets for context-contingent visually guided behavior: a frog will orient toward a small, moving stimulus (insect…
Silvio Ionta
Vision is the main entrance for environmental input to the human brain. Even if vision is our most used sensory modality, its importance is not limited to environmental exploration. Rather it has strong links to motor competences, further extending to cognitive and social aspects of human life. These multifaceted…
Amalia Papanikolaou, Georgios A. Keliris, T. Dorina Papageorgiou, Ulrich Schiefer + 2 more
Damage to the primary visual cortex (V1) leads to a visual field loss (scotoma) in the retinotopically corresponding part of the visual field. Nonetheless, a small amount of residual visual sensitivity persists within the blind field. This residual capacity has been linked to activity observed in the middle temporal…
Atena Akbari, Joseph S Gati, Peter Zeman, Brett Liem + 1 more
The neurons located in the striate cortex (V1) preferentially respond to the input from one eye or another, forming a fingerprint-like pattern of ocular dominance columns (ODCs). At this mesoscopic scale, accessible by ultra-high field fMRI, V1 is supplied/drained by a network of surface (pial) vessels that connect to…
Tristan A. Chaplin, Marcello G. P. Rosa, Leo L. Lui
The ability of animals to detect motion is critical for survival, and errors or even delays in motion perception may prove costly. In the natural world, moving objects in the visual field often produce concurrent sounds. Thus, it can highly advantageous to detect motion elicited from sensory signals of either modality…
Reinhard Werth, Thomas Jacobsen, Clara Casco
Although subjective conscious experience and introspection have long been considered unscientific and banned from psychology, they are indispensable in scientific practice. These terms are used in scientific contexts today; however, their meaning remains vague, and earlier objections to the distinction between…
Charles Q. Wu
At HVEI-2012, I presented a neurobiologically-based model for trichromatic color sensations in humans, mapping the neural substrate for color sensations to V1-L4—the thalamic recipient layer of the primary visual cortex. In this paper, I propose that V1-L4 itself consists of three distinct sub-layers that directly…
Fuyu Wang, Peng Wang, Yuyang Liu, Tao Zhou + 2 more
1## INTRODUCTION Neuroplasticity means the inherently dynamic biological ability of the central nervous system to develop maturation, to reshape structurally and functionally in related to experience, and to adapt after injury. The human visual cortex is the good tool to study the development and plasticity of the…
Li Zhaoping
Our brain recognizes only a tiny fraction of sensory input, due to an information processing bottleneck. This blinds us to most visual inputs. Since we are blind to this blindness, only a recent framework highlights this bottleneck by formulating vision as mainly looking and seeing. Looking selects a tiny fraction of…
Ilias Rentzeperis, Andrey R. Nikolaev, Daniel C. Kiper, Cees van Leeuwen
'Cees van Leeuwen'] To what extent does the visual system process color and form separately? Proponents of the segregation view claim that distinct regions of the cortex are dedicated to each of these two dimensions separately. However, evidence is accumulating that color and form processing may, at least to some…
Kevin K. Sit, Michael J. Goard
Perception of visual motion is important for a range of ethological behaviors in mammals. In primates, specific higher visual cortical regions are specialized for processing of coherent visual motion. However, the distribution of motion processing among visual cortical areas in mice is unclear, despite the powerful…
Hannah C Goldbach, Bradley Akitake, Caitlin E Leedy, Mark H Histed
Primary visual cortex (V1) in the mouse projects to numerous brain areas, including several secondary visual areas, frontal cortex, and basal ganglia. While it has been demonstrated that optogenetic silencing of V1 strongly impairs visually-guided behavior, it is not known which downstream areas are required for visual…
Semir Zeki
Area V5 of the visual brain, first identified anatomically in 1969 as a separate visual area, is critical for the perception of visual motion. As one of the most intensively studied parts of the visual brain, it has yielded many insights into how the visual brain operates. Among these are: the diversity of signals that…
Joana Carvalho, Azzurra Invernizzi, Joana Martins, Remco J. Renken + 1 more
The degree to which the adult human visual cortex retains the ability to functionally adapt to damage at the level of the eye remains ill-understood. Previous studies on cortical neuroplasticity primarily focused on the consequences of foveal visual field defects (VFD), yet these findings may not generalize to…
Leland L. Fleming, Matthew Defenderfer, Pinar Demirayak, Paul Stewart + 2 more
Human behavior can be remarkably shaped by experience, such as the removal of sensory input. Many studies of conditions such as stroke, limb amputation, and vision loss have examined how the removal of input changes brain function. However, an important question has yet to be answered: when input is lost, does the…
MARTIN I. SERENO, COLIN T. MCDONALD, JOHN M. ALLMAN
Dense retinotopy data sets were obtained by microelectrode visual receptive field mapping in dorsal and lateral visual cortex of anesthetized owl monkeys. The cortex was then physically flatmounted and stained for myelin or cytochrome oxidase. Retinotopic mapping data were digitized, interpolated to a uniform grid…