scholarly journals Modification of Visual Cortical Receptive Field Induced by Natural Stimuli

2012 ◽  
Vol 23 (8) ◽  
pp. 1923-1932 ◽  
Author(s):  
Yingjie Zhu ◽  
Haishan Yao
Keyword(s):  
Receptive Field ◽  
Natural Stimuli ◽  
Visual Cortical

scholarly journals Canonical and noncanonical features of the mouse visual cortical hierarchy

2020 ◽  
Author(s):  
Rinaldo D. D’Souza ◽  
Quanxin Wang ◽  
Weiqing Ji ◽  
Andrew M. Meier ◽  
Henry Kennedy ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Receptive Field ◽  
Active Vision ◽  
Structural Features ◽  
Hierarchical Organization ◽  
Hierarchical Level ◽  
Continuous Measure ◽  
Axonal Projections ◽  
Visual Cortical ◽  
Mouse Visual Cortex

ABSTRACTNeocortical circuit computations underlying active vision are performed by a distributed network of reciprocally connected, functionally specialized areas. Mouse visual cortex is a dense, hierarchically organized network, comprising subnetworks that form preferentially interconnected processing streams. To determine the detailed layout of the mouse visual hierarchy, laminar patterns formed by interareal axonal projections, originating in each of ten visual areas were analyzed. Reciprocally connected pairs of areas, and shared targets of pairs of source areas, exhibited structural features consistent with a hierarchical organization. Beta regression analyses, which estimated a continuous measure of hierarchical distance, indicated that the network comprises multiple hierarchies embedded within overlapping processing levels. Single unit recordings showed that within each processing stream, receptive field sizes typically increased with increasing hierarchical level; however, ventral stream areas showed overall larger receptive field diameters. Together, the results reveal canonical and noncanonical hierarchical network motifs in mouse visual cortex.

Effects of pattern deprivation on visual cortical cells in the rabbit: a reevaluation

1985 ◽  
Vol 53 (6) ◽  
pp. 1535-1550 ◽  
Author(s):  
E. H. Murphy
Keyword(s):  
Receptive Field ◽  
Direction Selectivity ◽  
Monocular Deprivation ◽  
Field Size ◽  
Orientation Tuning ◽  
Cortical Cells ◽  
Receptive Field Size ◽  
Pattern Deprivation ◽  
Contralateral Eye ◽  
Visual Cortical

The response properties of 217 cells recorded from the monocular segment of primary visual cortex in rabbits reared with lid suture of the contralateral eye (monocular deprivation, MD) were studied. These data were compared with 280 cells recorded from normal rabbits. There was no change in the percentage of orientation-selective cells, nonorientation-selective cells, or unmappable/unresponsive cells in MD animals compared with normals. Among orientation selective cells the orientation-tuning range of cells in MD animals was normal, and the predominance of cells with horizontal preferred orientation was maintained. However, some abnormalities were seen in orientation-selective cells of MD animals. These included an increased frequency of SI cells; a change in the distribution of preferred orientations; a disruption of the clustered organization of the cortex; a decrease in direction selectivity; an increase in the percentage of cells preferring slow stimulus movements and having low spontaneous activity; an increase in receptive-field size in all cell classes except SI. Among nonorientation-selective cells there was an increase in the percentage of movement sensitive cells and an increase in receptive-field size in MD animals. It is concluded that the effects of MD are much less severe in rabbit than in cat. In MD rabbits, many cells develop normally. In cells that do not develop normally, many of the changes observed can be interpreted as reflecting deficits in inhibitory functions.

Responses of Primate Visual Cortical V4 Neurons to Simultaneously Presented Stimuli

2002 ◽  
Vol 88 (3) ◽  
pp. 1128-1135 ◽  
Author(s):  
Timothy J. Gawne ◽  
Julie M. Martin
Keyword(s):  
Visual Cortex ◽  
Receptive Field ◽  
Firing Rate ◽  
Cortical Neurons ◽  
Clear Relationship ◽  
Substantial Fraction ◽  
Receptive Field Properties ◽  
Direct Support ◽  
V4 Neurons ◽  
Visual Cortical

We report here results from 45 primate V4 visual cortical neurons to the preattentive presentations of seven different patterns located in two separate areas of the same receptive field and to combinations of the patterns in the two locations. For many neurons, we could not determine any clear relationship for the responses to two simultaneous stimuli. However, for a substantial fraction of the neurons we found that the firing rate was well modeled as the maximum firing rate of each stimulus presented separately. It has previously been proposed that taking the maximum of the inputs (“MAX” operator) could be a useful operation for neurons in visual cortex, although there has until now been little direct physiological evidence for this hypothesis. Our results here provide direct support for the hypothesis that the MAX operator plays a significant (although certainly not exclusive) role in generating the receptive field properties of visual cortical neurons.

scholarly journals Receptive Field for Dorsal Cochlear Nucleus Neurons at Multiple Sound Levels

2007 ◽  
Vol 98 (6) ◽  
pp. 3505-3515 ◽  
Author(s):  
Sharba Bandyopadhyay ◽  
Lina A. J. Reiss ◽  
Eric D. Young
Keyword(s):  
Receptive Field ◽  
Cochlear Nucleus ◽  
Weighting Function ◽  
Sound Level ◽  
Second Order ◽  
Dorsal Cochlear Nucleus ◽  
Low Contrast ◽  
Spectral Contrast ◽  
Natural Stimuli ◽  
Frequency Components

Neurons in the dorsal cochlear nucleus (DCN) exhibit nonlinearities in spectral processing, which make it difficult to predict the neurons’ responses to stimuli. Here, we consider two possible sources of nonlinearity: nonmonotonic responses as sound level increases due to inhibition and interactions between frequency components. A spectral weighting function model of rate responses is used; the model approximates the neuron's rate response as a weighted sum of the frequency components of the stimulus plus a second-order sum that captures interactions between frequencies. Such models approximate DCN neurons well at low spectral contrast, i.e., when the SD (contrast) of the stimulus spectrum is limited to 3 dB. This model is compared with a first-order sum with weights that are explicit functions of sound level, so that the low-contrast model is extended to spectral contrasts of 12 dB, the range of natural stimuli. The sound-level–dependent weights improve prediction performance at large spectral contrast. However, the interactions between frequencies, represented as second-order terms, are more important at low spectral contrast. The level-dependent model is shown to predict previously described patterns of responses to spectral edges, showing that small changes in the inhibitory components of the receptive field can produce large changes in the responses of the neuron to features of natural stimuli. These results provide an effective way of characterizing nonlinear auditory neurons incorporating stimulus-dependent sensitivity changes. Such models could be used for neurons in other sensory systems that show similar effects.

scholarly journals Searching for object pointers in the visual cortex

2020 ◽  
Vol 123 (5) ◽  
pp. 1979-1994
Author(s):  
Shude D. Zhu ◽  
Li Alex Zhang ◽  
Rüdiger von der Heydt
Keyword(s):  
Visual Cortex ◽  
Receptive Field ◽  
Cortical Neurons ◽  
Visual Objects ◽  
Visual Cortical ◽  
The Way

The way we perceive objects as permanent contrasts with the short-lived responses of visual cortical neurons. A theory postulates pointers that give objects continuity, predicting a class of neurons that respond not only to visual objects but also when an occluded object moves into their receptive field. Here, we tested this theory with a novel paradigm in which a monkey freely scans an array of objects while some of them are transiently occluded.

scholarly journals Adaptation in the visual cortex: a case for probing neuronal populations with natural stimuli

F1000Research ◽  
2017 ◽  
Vol 6 ◽  
pp. 1246 ◽  
Author(s):  
Michoel Snow ◽  
Ruben Coen-Cagli ◽  
Odelia Schwartz
Keyword(s):  
Cortical Neurons ◽  
Natural Environments ◽  
Single Neurons ◽  
Neural Responses ◽  
Complete Understanding ◽  
Sensory Stimuli ◽  
Neuronal Populations ◽  
Natural Stimuli ◽  
The Past ◽  
Visual Cortical

The perception of, and neural responses to, sensory stimuli in the present are influenced by what has been observed in the past—a phenomenon known as adaptation. We focus on adaptation in visual cortical neurons as a paradigmatic example. We review recent work that represents two shifts in the way we study adaptation, namely (i) going beyond single neurons to study adaptation in populations of neurons and (ii) going beyond simple stimuli to study adaptation to natural stimuli. We suggest that efforts in these two directions, through a closer integration of experimental and modeling approaches, will enable a more complete understanding of cortical processing in natural environments.

Focal attention produces spatially selective processing in visual cortical areas V1, V2, and V4 in the presence of competing stimuli

1993 ◽  
Vol 70 (3) ◽  
pp. 909-919 ◽  
Author(s):  
B. C. Motter
Keyword(s):  
Receptive Field ◽  
Stimulus Presentation ◽  
Spatial Location ◽  
Differential Sensitivity ◽  
Orientation Tuning ◽  
Area V4 ◽  
Focal Attention ◽  
V4 Neurons ◽  
Visual Cortical ◽  
Competing Stimuli

1. The activity of single neurons was recorded in Macaca mulatta monkeys while they performed tasks requiring them to select a cued stimulus from an array of three to eight stimuli and report the orientation of that stimulus. Stimuli were presented in a circular array centered on the fixation target and scaled to place a single stimulus element within the receptive field of the neuron under study. The timing of the cuing event permitted the directing of visual attention to the spatial location of the correct stimulus before its presentation. 2. The effects of focal attention were examined in cortical visual areas V1, V2, and V4, where a total of 672 neurons were isolated with complete studies obtained for 94 V1, 74 V2, and 74 V4 neurons with receptive-field center eccentricities in the range 1.8-8 degrees. Under certain conditions, directed focal attention results in changes in the response of V1, V2, and V4 neurons to otherwise identical stimuli at spatially specific locations. 3. More than one-third of the neurons in each area displayed differential sensitivity when attention was directed toward versus away from the spatial location of the receptive field just before and during stimulus presentation. Both relative increases and decreases in neural activity were observed in association with attention directed at receptive-field stimuli. 4. The presence of multiple competing stimuli in the visual field was a major factor determining the presence or absence of differential sensitivity. About two-thirds of the neurons that were differentially sensitive to the attending condition in the presence of competing stimuli were not differentially sensitive when single stimuli were presented in control studies. For V1 and V2 neurons the presence of only a few (3-4) competing stimuli was sufficient for a majority of the neurons studied; a majority of the V4 neurons required six to eight stimuli in the array before significant differences between attending conditions occurred. 5. For V1 and V2 neurons the neuronal sensitivity differences between attending conditions were observed primarily at or near the peak of the orientation tuning sensitivity for each neuron; the differences were evident over a broader range of orientations in V4 neurons. 6. In conclusion, neural correlates of focal attentive processes can be observed in visual cortical processing in areas V1 and V2 as well as area V4 under conditions that require stimulus feature analysis and selective spatial processing within a field of competing stimuli.(ABSTRACT TRUNCATED AT 400 WORDS)

Comparison of neuronal selectivity for stimulus speed, length, and contrast in the prestriate visual cortical areas V4 and MT of the macaque monkey

1994 ◽  
Vol 71 (6) ◽  
pp. 2269-2280 ◽  
Author(s):  
K. Cheng ◽  
T. Hasegawa ◽  
K. S. Saleem ◽  
K. Tanaka
Keyword(s):  
Receptive Field ◽  
Luminance Contrast ◽  
Macaque Monkey ◽  
Stimulus Motion ◽  
Temporal Area ◽  
Area V4 ◽  
Optimal Speed ◽  
Stimulus Speed ◽  
Stimulus Length ◽  
Visual Cortical

1. Prestriate area V4 and the middle temporal area (MT) compose the first stage in which the ventral and dorsal visual cortical pathways are segregated. To better known the functional dichotomy between the two pathways at this level, we recorded cell responses from V4 and MT using anesthetized, immobilized macaque monkeys and compared the selectivity for speed of stimulus motion and stimulus length and the sensitivity to luminance contrast between the two areas. 2. V4 cells were as selective as MT cells for speed. The sharpness of tuning was not different between the two populations. The optimal speed varied widely in both areas, but both of the two distributions showed peaks at 32 degrees/s. 3. V4 and MT cells were similar in that about one-half of the cells (45% in V4 and 48% in MT) showed inhibition by long (16 degrees) bars. However, V4 cells preferred stimuli whose lengths were distributed around the lengths of the receptive field, whereas an overwhelming majority of MT cells preferred stimuli whose lengths were much shorter than the lengths of the receptive field. 4. The cutoff contrast at which one-half the maximum response was elicited was distributed widely in both areas, and the two distributions considerably overlapped. MT cells as a whole, however, were slightly more sensitive to the luminance contrast than V4 cells. 5. There was a tendency toward local clustering for cells with similar speed preferences in MT but not in V4. Pairs of MT cells recorded within 400 microns had smaller difference in the optimal speed than that of cell pairs taken randomly from the whole sample of MT cells.

Receptive-field structure of optic flow responsive Purkinje cells in the vestibulocerebellum of pigeons

2006 ◽  
Vol 23 (1) ◽  
pp. 115-126 ◽  
Author(s):  
IAN R. WINSHIP ◽  
DOUGLAS R.W. WYLIE
Keyword(s):  
Receptive Field ◽  
Purkinje Cells ◽  
Optic Flow ◽  
Flow Patterns ◽  
Field Structure ◽  
Local Motion ◽  
Cortical Areas ◽  
Invertebrate Species ◽  
Visual Cortical ◽  
Complex Computer

Neurons sensitive to optic flow patterns have been recorded in the the olivo-vestibulocerebellar pathway and extrastriate visual cortical areas in vertebrates, and in the visual neuropile of invertebrates. The complex spike activity (CSA) of Purkinje cells in the vestibulocerebellum (VbC) responds best to patterns of optic flow that result from either self-rotation or self-translation. Previous studies have suggested that these neurons have a receptive-field (RF) structure that “approximates” the preferred optic flowfield with a “bipartite” organization. Contrasting this, studies in invertebrate species indicate that optic flow sensitive neurons are precisely tuned to their preferred flowfield, such that the local motion sensitivities and local preferred directions within their RFs precisely match the local motion in that region of the preferred flowfield. In this study, CSA in the VbC of pigeons was recorded in response to a set of complex computer-generated optic flow stimuli, similar to those used in previous studies of optic flow neurons in primate extrastriate visual cortex, to test whether the receptive field was of a precise or bipartite organization. We found that these RFs were not precisely tuned to optic flow patterns. Rather, we conclude that these neurons have a bipartite RF structure that approximates the preferred optic flowfield by pooling motion subunits of only a few different direction preferences.

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