scholarly journals Adaptive Integration in the Visual Cortex by Depressing Recurrent Cortical Circuits

2008 ◽  
Vol 20 (7) ◽  
pp. 1847-1872 ◽  
Author(s):  
Mark C. W. van Rossum ◽  
Matthijs A. A. van der Meer ◽  
Dengke Xiao ◽  
Mike W. Oram
Keyword(s):  
Visual Cortex ◽  
Physiological Data ◽  
High Contrast ◽  
Cortical Circuits ◽  
Response Latencies ◽  
Low Contrast ◽  
Visual Areas ◽  
Higher Visual Areas ◽  
Recurrent Connections

Neurons in the visual cortex receive a large amount of input from recurrent connections, yet the functional role of these connections remains unclear. Here we explore networks with strong recurrence in a computational model and show that short-term depression of the synapses in the recurrent loops implements an adaptive filter. This allows the visual system to respond reliably to deteriorated stimuli yet quickly to high-quality stimuli. For low-contrast stimuli, the model predicts long response latencies, whereas latencies are short for high-contrast stimuli. This is consistent with physiological data showing that in higher visual areas, latencies can increase more than 100 ms at low contrast compared to high contrast. Moreover, when presented with briefly flashed stimuli, the model predicts stereotypical responses that outlast the stimulus, again consistent with physiological findings. The adaptive properties of the model suggest that the abundant recurrent connections found in visual cortex serve to adapt the network's time constant in accordance with the stimulus and normalizes neuronal signals such that processing is as fast as possible while maintaining reliability.

scholarly journals The essential role of feedback processing for figure-ground perception in mice

2018 ◽  
Author(s):  
Lisa Kirchberger ◽  
Sreedeep Mukherjee ◽  
Ulf H. Schnabel ◽  
Enny H. van Beest ◽  
Areg Barsegyan ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Visual Perception ◽  
Essential Role ◽  
Pyramidal Cells ◽  
Neuronal Responses ◽  
Feedback Processing ◽  
Visual Areas ◽  
Higher Visual Areas ◽  
Delayed Phase

AbstractThe segregation of figures from the background is an important step in visual perception. In primary visual cortex, figures evoke stronger activity than backgrounds during a delayed phase of the neuronal responses, but it is unknown how this figure-ground modulation (FGM) arises and whether it is necessary for perception. Here we show, using optogenetic silencing in mice, that the delayed V1 response phase is necessary for figure-ground segregation. Neurons in higher visual areas also exhibit FGM and optogenetic silencing of higher areas reduced FGM in V1. In V1, figures elicited higher activity of vasoactive intestinal peptide-expressing (VIP) interneurons than the background, whereas figures suppressed somatostatin-positive interneurons, resulting in an increased activation of pyramidal cells. Optogenetic silencing of VIP neurons reduced FGM in V1, indicating that disinhibitory circuits contribute to FGM. Our results provide new insight in how lower and higher areas of the visual cortex interact to shape visual perception.

scholarly journals The essential role of recurrent processing for figure-ground perception in mice

2021 ◽  
Vol 7 (27) ◽  
pp. eabe1833
Author(s):  
Lisa Kirchberger ◽  
Sreedeep Mukherjee ◽  
Ulf H. Schnabel ◽  
Enny H. van Beest ◽  
Areg Barsegyan ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Visual Perception ◽  
Pyramidal Cells ◽  
Neuronal Responses ◽  
Visual Areas ◽  
Recurrent Processing ◽  
Higher Visual Areas ◽  
Delayed Phase ◽  
Insight Into

The segregation of figures from the background is an important step in visual perception. In primary visual cortex, figures evoke stronger activity than backgrounds during a delayed phase of the neuronal responses, but it is unknown how this figure-ground modulation (FGM) arises and whether it is necessary for perception. Here, we show, using optogenetic silencing in mice, that the delayed V1 response phase is necessary for figure-ground segregation. Neurons in higher visual areas also exhibit FGM and optogenetic silencing of higher areas reduced FGM in V1. In V1, figures elicited higher activity of vasoactive intestinal peptide–expressing (VIP) interneurons than the background, whereas figures suppressed somatostatin-positive interneurons, resulting in an increased activation of pyramidal cells. Optogenetic silencing of VIP neurons reduced FGM in V1, indicating that disinhibitory circuits contribute to FGM. Our results provide insight into how lower and higher areas of the visual cortex interact to shape visual perception.

scholarly journals Unique spatial integration in mouse primary visual cortex and higher visual areas

2019 ◽  
Author(s):  
Kevin A. Murgas ◽  
Ashley M. Wilson ◽  
Valerie Michael ◽  
Lindsey L. Glickfeld
Keyword(s):  
Visual Cortex ◽  
Visual System ◽  
Primary Visual Cortex ◽  
Spatial Information ◽  
Spatial Scales ◽  
Spatial Integration ◽  
Global Features ◽  
Wide Range ◽  
Visual Areas ◽  
Higher Visual Areas

AbstractNeurons in the visual system integrate over a wide range of spatial scales. This diversity is thought to enable both local and global computations. To understand how spatial information is encoded across the mouse visual system, we use two-photon imaging to measure receptive fields in primary visual cortex (V1) and three downstream higher visual areas (HVAs): LM (lateromedial), AL (anterolateral) and PM (posteromedial). We find significantly larger receptive field sizes and less surround suppression in PM than in V1 or the other HVAs. Unlike other visual features studied in this system, specialization of spatial integration in PM cannot be explained by specific projections from V1 to the HVAs. Instead, our data suggests that distinct connectivity within PM may support the area’s unique ability to encode global features of the visual scene, whereas V1, LM and AL may be more specialized for processing local features.

scholarly journals Shape-centered representations of bounded regions of space mediate the transformation of retinotopic representations into conscious perception of objects

2020 ◽  
Author(s):  
G. Vannuscorps ◽  
A. Galaburda ◽  
A. Caramazza
Keyword(s):  
Visual Cortex ◽  
Visual Representations ◽  
Object Perception ◽  
Frame Of Reference ◽  
Conscious Perception ◽  
High Contrast ◽  
Bounded Region ◽  
Shape Representations ◽  
Low Contrast ◽  
Axis Of Symmetry

AbstractThe primary visual cortex represents the retinotopic orientation of visual primitives (edges, blobs, bars), but our conscious perception is of orientated objects (e.g., dogs, forks) in the environment. How this transformation operates remains unknown. We report here the study of a young woman presenting with an extraordinarily clear and informative visual disorder that affects highly specific aspects of object perception allowing precise inferences about the type and properties of visual representations that mediate this transformation. Davida perceives sharp-edged 2D bounded regions of space of medium to high contrast as if they were plane-rotated by 90, 180 or 270 degrees around their center, mirrored across their own axes, or both. In contrast, her perception of strongly blurred or very low contrast shapes, and of compound shapes emerging from a collection of bounded elements, is intact. The nature of her errors implies that visual perception is mediated by a representation of each bounded region of space in a shape-centered coordinate system aligned on either the shape’s most elongated part or on the shape’s axis of symmetry and centered either at the midpoint of the shape’s most elongated part or at the shape’s centroid. The selectivity of her disorder to sharp-edged medium to high-contrast stimuli additionally suggests that duplicate shape-centered representations are computed in parallel from information derived from the parvocellular and magnocellular subcortical channels and integrated precisely at the level at which shape representations must be mapped onto a behaviorally relevant frame of reference.

scholarly journals Spatial modulation of visual signals arises in cortex with active navigation

2019 ◽  
Author(s):  
E. Mika Diamanti ◽  
Charu Bai Reddy ◽  
Sylvia Schröder ◽  
Tomaso Muzzu ◽  
Kenneth D. Harris ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Primary Visual Cortex ◽  
Spatial Position ◽  
Visual Signals ◽  
Spatial Modulation ◽  
Visual Responses ◽  
Active Behavior ◽  
Visual Areas ◽  
Familiar Environment ◽  
Higher Visual Areas

During navigation, the visual responses of neurons in primary visual cortex (V1) are modulated by the animal’s spatial position. Here we show that this spatial modulation is similarly present across multiple higher visual areas but largely absent in the main thalamic pathway into V1. Similar to hippocampus, spatial modulation in visual cortex strengthens with experience and requires engagement in active behavior. Active navigation in a familiar environment, therefore, determines spatial modulation of visual signals starting in the cortex.

scholarly journals Increased region of surround stimulation enhances contextual feedback and feedforward processing in human V1

2021 ◽  
Author(s):  
Yulia Revina ◽  
Lucy S Petro ◽  
Cristina B Denk-Florea ◽  
Isa S Rao ◽  
Lars Muckli
Keyword(s):  
Visual Cortex ◽  
Primary Visual Cortex ◽  
Contextual Information ◽  
Receptive Fields ◽  
Cortical Processing ◽  
Feedback Information ◽  
V1 Neurons ◽  
Visual Areas ◽  
Feedforward Processing ◽  
Higher Visual Areas

The majority of synaptic inputs to the primary visual cortex (V1) are non-feedforward, instead originating from local and anatomical feedback connections. Animal electrophysiology experiments show that feedback signals originating from higher visual areas with larger receptive fields modulate the surround receptive fields of V1 neurons. Theories of cortical processing propose various roles for feedback and feedforward processing, but systematically investigating their independent contributions to cortical processing is challenging because feedback and feedforward processes coexist even in single neurons. Capitalising on the larger receptive fields of higher visual areas compared to primary visual cortex (V1), we used an occlusion paradigm that isolates top-down influences from feedforward processing. We utilised functional magnetic resonance imaging (fMRI) and multi-voxel pattern analysis methods in humans viewing natural scene images. We parametrically measured how the availability of contextual information determines the presence of detectable feedback information in non-stimulated V1, and how feedback information interacts with feedforward processing. We show that increasing the visibility of the contextual surround increases scene-specific feedback information, and that this contextual feedback enhances feedforward information. Our findings are in line with theories that cortical feedback signals transmit internal models of predicted inputs.

scholarly journals Laminar-specific cortico-cortical loops in mouse visual cortex

2019 ◽  
Author(s):  
Hedi Young ◽  
Beatriz Belbut ◽  
Margarida Baeta ◽  
Leopoldo Petreanu
Keyword(s):  
Visual Cortex ◽  
Cortical Circuits ◽  
Cortical Input ◽  
Cortical Connections ◽  
Cortical Hierarchy ◽  
Input Source ◽  
Innervation Patterns ◽  
Mouse Visual Cortex ◽  
Apical Dendrites

AbstractMany theories propose recurrent interactions across the cortical hierarchy, but it is unclear if cortical circuits are selectively wired to implement looped computations. Using subcellular channelrhodopsin-2-assisted circuit mapping in mouse visual cortex, we compared feedforward (FF) or feedback (FB) cortico-cortical input to cells projecting back to the input source (looped neurons) with cells projecting to a different cortical or subcortical area (non-looped neurons). Despite having different laminar innervation patterns, FF and FB afferents showed similar cell-type selectivity, making stronger connections with looped neurons versus non-looped neurons in layer (L) 5 and L6, but not in L2/3. FB inputs preferentially innervated the apical tufts of looped L5 neurons, but not their perisomatic dendrites. Our results reveal that interareal cortical connections are selectively wired into monosynaptic excitatory loops involving L6 and the apical dendrites of L5 neurons, supporting a role of these circuit elements in hierarchical recurrent computations.

scholarly journals Magnitude, time course, and specificity of rapid adaptation across mouse visual areas

2020 ◽  
Vol 124 (1) ◽  
pp. 245-258 ◽  
Author(s):  
Miaomiao Jin ◽  
Lindsey L. Glickfeld
Keyword(s):  
Visual Cortex ◽  
Visual System ◽  
Primary Visual Cortex ◽  
Sensory Processing ◽  
Time Course ◽  
Recent Experience ◽  
Rapid Adaptation ◽  
It Impacts ◽  
Visual Areas ◽  
Higher Visual Areas

Rapid adaptation dynamically alters sensory signals to account for recent experience. To understand how adaptation affects sensory processing and perception, we must determine how it impacts the diverse set of cortical and subcortical areas along the hierarchy of the mouse visual system. We find that rapid adaptation strongly impacts neurons in primary visual cortex, the higher visual areas, and the colliculus, consistent with its profound effects on behavior.

Propagation of spiking regularity in feedforward networks with recurrent connections

2021 ◽  
pp. 2150101
Author(s):  
Tianshi Gao ◽  
Bin Deng ◽  
Jixuan Wang ◽  
Jiang Wang ◽  
Guosheng Yi
Keyword(s):  
Synaptic Weight ◽  
Synaptic Connection ◽  
Feedforward Networks ◽  
Critical Window ◽  
Connection Probability ◽  
Visual Areas ◽  
Circuit Structure ◽  
Cortical Circuit ◽  
Recurrent Connections

The regularity of the inter-spike intervals (ISIs) gives a critical window into how the information is coded temporally in the cortex. Previous researches mostly adopt pure feedforward networks (FFNs) to study how the network structure affects spiking regularity propagation, which ignore the role of local dynamics within the layer. In this paper, we construct an FFN with recurrent connections and investigate the propagation of spiking regularity. We argue that an FFN with recurrent connections serves as a basic circuit to explain that the regularity increases as spikes propagate from middle temporal visual areas to higher cortical areas. We find that the reduction of regularity is related to the decreased complexity of the shared activity co-fluctuations. We show in simulations that there is an appropriate excitation–inhibition ratio maximizing the regularity of deeper layers. Furthermore, it is demonstrated that collective temporal regularity in deeper layers exhibits resonance-like behavior with respect to both synaptic connection probability and synaptic weight. Our work provides a critical link between cortical circuit structure and realistic spiking regularity.

scholarly journals Anticipatory Changes in Regional Cerebral Hemodynamics: A New Role for Dopamine?

2009 ◽  
Vol 101 (6) ◽  
pp. 2738-2740 ◽  
Author(s):  
Can Ozan Tan
Keyword(s):  
Visual Cortex ◽  
Primary Visual Cortex ◽  
Neural Activity ◽  
Cerebral Hemodynamics ◽  
Physiological Data ◽  
Cerebral Microcirculation ◽  
Hemodynamic Responses ◽  
On Demand ◽  
Demand Allocation

Recently, adaptively timed, anticipatory changes in hemodynamic responses, independent of neural activity, were described in primate primary visual cortex. Task-related properties of these responses point to a possible link between regional cerebral microcirculation and dopaminergic signaling. In this report, this link is elaborated on the basis of known physiological data and further experiments are proposed to test the possible role of dopamine in task-dependent, “on-demand” allocation of metabolic resources.

Sign in / Sign up

Export Citation Format

Share Document