Receptive fields of visual cortical neurons during changes in parameters of photic stimulation in cats

1980 ◽  
Vol 12 (2) ◽  
pp. 77-84
Author(s):  
I. A. Shevelev ◽  
V. G. Marchenko ◽  
I. V. Maksimova
Keyword(s):  
Cortical Neurons ◽  
Receptive Fields ◽  
Photic Stimulation ◽  
Visual Cortical

Functional characteristics of visual cortical neurons during local photic stimulation of their receptive fields in cats

1983 ◽  
Vol 15 (1) ◽  
pp. 49-56
Author(s):  
N. A. Lazareva ◽  
R. V. Novikova ◽  
A. S. Tikhomirov ◽  
M. A. Kulikov
Keyword(s):  
Cortical Neurons ◽  
Receptive Fields ◽  
Photic Stimulation ◽  
Functional Characteristics ◽  
Visual Cortical ◽  
Stimulation Of

The response dynamics of primate visual cortical neurons to simulated optical blur

2009 ◽  
Vol 26 (4) ◽  
pp. 411-420 ◽  
Author(s):  
MICHAEL L. RISNER ◽  
TIMOTHY J. GAWNE
Keyword(s):  
Cortical Neurons ◽  
Receptive Fields ◽  
Luminance Contrast ◽  
Form Perception ◽  
Response Dynamics ◽  
V1 Neurons ◽  
Spatial Frequencies ◽  
Wide Range ◽  
Optical Blur ◽  
Visual Cortical

AbstractNeurons in visual cortical area V1 typically respond well to lines or edges of specific orientations. There have been many studies investigating how the responses of these neurons to an oriented edge are affected by changes in luminance contrast. However, in natural images, edges vary not only in contrast but also in the degree of blur, both because of changes in focus and also because shadows are not sharp. The effect of blur on the response dynamics of visual cortical neurons has not been explored. We presented luminance-defined single edges in the receptive fields of parafoveal (1–6 deg eccentric) V1 neurons of two macaque monkeys trained to fixate a spot of light. We varied the width of the blurred region of the edge stimuli up to 0.36 deg of visual angle. Even though the neurons responded robustly to stimuli that only contained high spatial frequencies and 0.36 deg is much larger than the limits of acuity at this eccentricity, changing the degree of blur had minimal effect on the responses of these neurons to the edge. Primates need to measure blur at the fovea to evaluate image quality and control accommodation, but this might only involve a specialist subpopulation of neurons. If visual cortical neurons in general responded differently to sharp and blurred stimuli, then this could provide a cue for form perception, for example, by helping to disambiguate the luminance edges created by real objects from those created by shadows. On the other hand, it might be important to avoid the distraction of changing blur as objects move in and out of the plane of fixation. Our results support the latter hypothesis: the responses of parafoveal V1 neurons are largely unaffected by changes in blur over a wide range.

scholarly journals Development of cortical orientation selectivity in the absence of visual experience with contour

2011 ◽  
Vol 106 (4) ◽  
pp. 1923-1932 ◽  
Author(s):  
Tomokazu Ohshiro ◽  
Shaista Hussain ◽  
Michael Weliky
Keyword(s):  
Cortical Neurons ◽  
Computational Models ◽  
Visual Experience ◽  
Receptive Fields ◽  
Orientation Selectivity ◽  
Experimental Result ◽  
Full Development ◽  
Visual Inputs ◽  
Eye Opening ◽  
Visual Cortical

Visual cortical neurons are selective for the orientation of lines, and the full development of this selectivity requires natural visual experience after eye opening. Here we examined whether this selectivity develops without seeing lines and contours. Juvenile ferrets were reared in a dark room and visually trained by being shown a movie of flickering, sparse spots. We found that despite the lack of contour visual experience, the cortical neurons of these ferrets developed strong orientation selectivity and exhibited simple-cell receptive fields. This finding suggests that overt contour visual experience is unnecessary for the maturation of orientation selectivity and is inconsistent with the computational models that crucially require the visual inputs of lines and contours for the development of orientation selectivity. We propose that a correlation-based model supplemented with a constraint on synaptic strength dynamics is able to account for our experimental result.

scholarly journals FSRFNet: Feature-Selective and Spatial Receptive Fields Networks

2019 ◽  
Vol 9 (19) ◽  
pp. 3954 ◽  
Author(s):  
Ma ◽  
Yang ◽  
Yu
Keyword(s):  
Receptive Field ◽  
Spatial Attention ◽  
Cognitive Neuroscience ◽  
Cortical Neurons ◽  
Network Architecture ◽  
Receptive Fields ◽  
Field Size ◽  
Visual Cortical ◽  
Neuroscience Community ◽  
Architectural Unit

The attention mechanism plays a crucial role in the human visual experience. In the cognitive neuroscience community, the receptive field size of visual cortical neurons is regulated by the additive effect of feature-selective and spatial attention. We propose a novel architectural unit called a “Feature-selective and Spatial Receptive Fields” (FSRF) block that implements adaptive receptive field sizes of neurons through the additive effects of feature-selective and spatial attention. We show that FSRF blocks can be inserted into the architecture of existing convolutional neural networks to form an FSRF network architecture, and test its generalization capabilities on different datasets.

Receptive-field properties of transcallosal visual cortical neurons in the normal and reeler mouse

1983 ◽  
Vol 50 (4) ◽  
pp. 838-848 ◽  
Author(s):  
P. A. Simmons ◽  
A. L. Pearlman
Keyword(s):  
Receptive Field ◽  
Cortical Neurons ◽  
Receptive Fields ◽  
Unit Recording ◽  
Stimulus Velocity ◽  
Bipolar Electrodes ◽  
Receptive Field Properties ◽  
Significant Difference ◽  
Visual Cortical ◽  
Normal Cortex

The receptive-field properties of neurons in the striate visual cortex of normal and reeler mutant mice were studied with single-unit recording methods in order to determine whether the connections underlying these properties are altered by the developmental abnormality in neuronal position that characterizes reeler neocortex. Neurons with a projection through the corpus callosum were selected for study because they form a physiologically identifiable class of visual cortical neurons with a characteristic distribution of receptive-field properties that can be compared for normal and reeler cortex. Transcallosal cortical neurons in area 17 near its border with area 18a were identified by antidromic stimulation delivered through bipolar electrodes in the contralateral cortex. A computer controlled the visual stimuli, data acquisition, and analysis. Transcallosal neurons were principally found in layers II-III and V in the normal cortex and in a broand band deep in the reeler cortex. These populations had similar distributions of antidromic latencies, indicating that the neurons sampled from normal and reeler cortex were taken from populations with similar axonal diameters and soma sizes. The receptive-field properties of 46 units in 22 normal mice and 28 units in 11 reeler mice were characterized. Transcallosal neurons in both normal and reeler cortex were usually binocularly responsive and dominated by input from the contralateral eye. They exhibited either nonoriented (31 and 48%, respectively) or oriented (69 and 52%) receptive fields. Tuning 10 stimulus velocity was broad, with peak velocity sensitivities ranging from 1 to 1,000 degrees/s. Directional selectivity was present in 41% of normal units ad 32% of reeler units. There was no significant difference between normal and reeler cortex in the distribution of these properties. Transcallosal neurons were also examined for the presence of an inhibitory surround by comparing their responses to moving or stationary stimuli of varying sizes. Of the tested neurons, most (11/17 in normal cortex, 6/9 in reeler) showed evidence of a decrease in response to large moving stimuli. A large proportion (16/20) of normal neurons tested with stationary flashing stimuli had some degree of surround inhibition whereas significantly fewer (5/17) neurons in reeler cortex had this property. Thus, transcallosal neurons in reeler cortex less frequently had an inhibitory surround demonstrable with stationary flashing stimuli, but this difference between normal and reeler was not apparent with a moving stimulus.(ABSTRACT TRUNCATED AT 400 WORDS)

Constraint on the Number of Synaptic Inputs to a Visual Cortical Neuron Controls Receptive Field Formation

2009 ◽  
Vol 21 (9) ◽  
pp. 2554-2580 ◽  
Author(s):  
Shigeru Tanaka ◽  
Masanobu Miyashita
Keyword(s):  
Cortical Neurons ◽  
Metabotropic Glutamate Receptor ◽  
Hebbian Learning ◽  
Receptive Fields ◽  
Gradual Transition ◽  
Synaptic Inputs ◽  
Metabotropic Glutamate ◽  
Visual Cortical Neuron ◽  
Visual Cortical ◽  
Activity Dependent

To date, Hebbian learning combined with some form of constraint on synaptic inputs has been demonstrated to describe well the development of neural networks. The previous models revealed mathematically the importance of synaptic constraints to reproduce orientation selectivity in the visual cortical neurons, but biological mechanisms underlying such constraints remain unclear. In this study, we addressed this issue by formulating a synaptic constraint based on activity-dependent mechanisms of synaptic changes. Particularly, considering metabotropic glutamate receptor-mediated long-term depression, we derived synaptic constraint that suppresses the number of inputs from individual presynaptic neurons. We performed computer simulations of the activity-dependent self-organization of geniculocortical inputs with the synaptic constraint and examined the formation of receptive fields (RFs) of model visual cortical neurons. When we changed the magnitude of the synaptic constraint, we found the emergence of distinct RF structures such as concentric RFs, simple-cell-like RFs, and double-oriented RFs and also a gradual transition between spatiotemporal separable and inseparable RFs. Thus, the model based on the synaptic constraint derived from biological consideration can account systematically for the repertoire of RF structures observed in the primary visual cortices of different species for the first time.

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