Contextual influences on the directional responses of tectal cells in pigeons

2002 ◽  
Vol 19 (2) ◽  
pp. 133-144 ◽  
Author(s):  
HONG-JIN SUN ◽  
JIAN ZHAO ◽  
TRACY L. SOUTHALL ◽  
BIN XU
Keyword(s):  
Visual Motion ◽  
Receptive Fields ◽  
Extracellular Recording ◽  
Contextual Effects ◽  
Object Motion ◽  
Contextual Influences ◽  
Test Spot ◽  
Induced Motion ◽  
Tectal Neurons ◽  
Background Motion

Contrary to the traditional view that receptive fields are limited in spatial extent, recent studies have indicated that the response of neurons to a local stimulus within the receptive field can be modulated by stimulation of the surrounding region. Here we quantified the nature of these contextual effects on visual motion responses of neurons in the pigeon's optic tectum using standard extracellular recording techniques. All of the cells tested responded well to a test spot moving across their receptive fields. When a background pattern was moved in the same or in a similar direction as that of the test spot, the responses of most deep tectal neurons to the test spot were maximally inhibited. Movement of the background in the opposite or near opposite direction produced minimal inhibition or even facilitation. For some deep tectal neurons, this directionally selective modulation by the moving background was maintained when the background motion was paired with different movement directions of the test spot (including both the preferred and least preferred directions). Thus, this selectivity for opposing motion was independent of the absolute direction of either the test spot or the background, a finding which is consistent with the results reported by Frost and Nakayama (1983), although they did not include all test spot directions. For some other neurons, identified here for the first time, the background movement selectively modulated the response only when the test spot moved in the neuron's preferred directions. These neurons lost selectivity for opposing motion when the test spot moved in nonpreferred directions. The significance of these contextual effects on the motion response of tectal neurons may be related to how the brain distinguishes self-induced motion from object motion and segregates figure from ground.

Location and Functional Definition of Human Visual Motion Organization Using Functional Magnetic Resonance Imaging

2011 ◽  
pp. 18-27
Author(s):  
Tianyi Yan ◽  
Jinglong Wu
Keyword(s):  
Visual Field ◽  
Visual Motion ◽  
Receptive Fields ◽  
Superior Temporal Sulcus ◽  
Object Motion ◽  
Posterior Limb ◽  
Medial Superior Temporal ◽  
Processing Abilities ◽  
Mst Neurons ◽  
Definition Of

In humans, functional imaging studies have found a homolog of the macaque motion complex, MT+, which is suggested to contain both the middle temporal (MT) and medial superior temporal (MST) areas in the ascending limb of the inferior temporal sulcus. In the macaque, the motion-sensitive MT and MST areas are adjacent in the superior temporal sulcus. Electrophysiology has identified several motion-selective regions in the superior temporal sulcus (STS) of the macaque. Two of the best-studied areas include the MT and MST areas. The MT area has strong projections to the adjacent MST area and is typically subdivided into the dorsal (MSTd) and lateral (MSTl) subregions. While MT encodes the basic elements of motion, MST has higher-order motion-processing abilities and has been implicated in the perception of both object motion and self motion. The macaque MST area has been shown to have considerably larger receptive fields than the MT area. The receptive fields of MT cells typically extend only a few degrees into the ipsilateral visual field, while MST neurons have receptive fields that extend well into the ipsilateral visual field. This study tentatively identifies these subregions as the human homologs of the macaque MT and MST areas, respectively (Fig. 1). Putative human MT and MST areas were typically located on the posterior/ventral and anterior/dorsal banks of a dorsal/posterior limb of the inferior temporal sulcus. These locations are similar to their relative positions in the macaque superior temporal sulcus.

scholarly journals Anticipatory responses along motion trajectories in awake monkey area V1

2020 ◽  
Author(s):  
Giacomo Benvenuti ◽  
Sandrine Chemla ◽  
Arjan Boonman ◽  
Laurent Perrinet ◽  
Guillaume S Masson ◽  
...  
Keyword(s):  
Visual Motion ◽  
Receptive Fields ◽  
Contextual Effects ◽  
List Type ◽  
Motion Trajectories ◽  
V1 Neurons ◽  
Motion Integration ◽  
Feedback Networks ◽  
Lateral Propagation ◽  
Spiking Activity

ABSTRACTWhat are the neural mechanisms underlying motion integration of translating objects? Visual motion integration is generally conceived of as a feedforward, hierarchical, information processing. However, feedforward models fail to account for many contextual effects revealed using natural moving stimuli. In particular, a translating object evokes a sequence of transient feedforward responses in the primary visual cortex but also propagations of activity through horizontal and feedback pathways. We investigated how these pathways shape the representation of a translating bar in monkey V1. We show that, for long trajectories, spiking activity builds-up hundreds of milliseconds before the bar enters the neurons’ receptive fields. Using VSDI and LFP recordings guided by a phenomenological model of propagation dynamics, we demonstrate that this anticipatory response arises from the interplay between horizontal and feedback networks driving V1 neurons well ahead of their feedforward inputs. This mechanism could subtend several perceptual contextual effects observed with translating objects.HighlightsOur hypothesis is that lateral propagation of activity in V1 contributes to the integration of translating stimuliConsistent with this hypothesis, we find that a translating bar induces anticipatory spiking activity in V1 neurons.A V1 model describes how this anticipation can arise from inter and intra-cortical lateral propagation of activity.The dynamic of VSDi and LFP signals in V1 is consistent with the predictions made by the model.The intra-cortical origin is further confirmed by the fact that a bar moving from the ipsilateral hemifield does not evoke anticipation.Horizontal and feedback input are not only modulatory but can also drive spiking responses in specific contexts.

scholarly journals Directional selectivity and its use in early visual processing

1981 ◽  
Vol 211 (1183) ◽  
pp. 151-180 ◽  
Keyword(s):  
Visual Processing ◽  
Visual Motion ◽  
Time Derivative ◽  
Receptive Fields ◽  
Specific Model ◽  
Zero Crossings ◽  
Second Stage ◽  
Early Visual Processing ◽  
Local Direction ◽  
Zero Values

The construction of directionally selective units, and their use in the processing of visual motion, are considered. The zero crossings of ∇ 2 G(x, y) ∗ I(x, y) are located, as in Marr & Hildreth (1980). That is, the image is filtered through centre-surround receptive fields, and the zero values in the output are found. In addition, the time derivative ∂[∇ 2 G(x, y) ∗ l(x, y) ]/∂ t is measured at the zero crossings, and serves to constrain the local direction of motion to within 180°. The direction of motion can be determined in a second stage, for example by combining the local constraints. The second part of the paper suggests a specific model of the information processing by the X and Y cells of the retina and lateral geniculate nucleus, and certain classes of cortical simple cells. A number of psychophysical and neurophysiological predictions are derived from the theory.

scholarly journals Human visual motion perception shows hallmarks of Bayesian structural inference

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sichao Yang ◽  
Johannes Bill ◽  
Jan Drugowitsch ◽  
Samuel J. Gershman
Keyword(s):  
Motion Perception ◽  
Visual Motion ◽  
Probabilistic Reasoning ◽  
Choice Model ◽  
Human Motion ◽  
Object Motion ◽  
Ideal Observer ◽  
Structure Identification ◽  
Structural Inference ◽  
Visual Motion Perception

AbstractMotion relations in visual scenes carry an abundance of behaviorally relevant information, but little is known about how humans identify the structure underlying a scene’s motion in the first place. We studied the computations governing human motion structure identification in two psychophysics experiments and found that perception of motion relations showed hallmarks of Bayesian structural inference. At the heart of our research lies a tractable task design that enabled us to reveal the signatures of probabilistic reasoning about latent structure. We found that a choice model based on the task’s Bayesian ideal observer accurately matched many facets of human structural inference, including task performance, perceptual error patterns, single-trial responses, participant-specific differences, and subjective decision confidence—especially, when motion scenes were ambiguous and when object motion was hierarchically nested within other moving reference frames. Our work can guide future neuroscience experiments to reveal the neural mechanisms underlying higher-level visual motion perception.

Area MT Neurons Respond to Visual Motion Distant From Their Receptive Fields

2005 ◽  
Vol 94 (6) ◽  
pp. 4156-4167 ◽  
Author(s):  
Daniel Zaksas ◽  
Tatiana Pasternak
Keyword(s):  
Time Course ◽  
Visual Motion ◽  
Cognitive Task ◽  
Receptive Fields ◽  
Direction Selectivity ◽  
Task Demands ◽  
Visual Signals ◽  
Area Mt ◽  
Mt Neurons ◽  
Stimulus Offset

Neurons in cortical area MT have localized receptive fields (RF) representing the contralateral hemifield and play an important role in processing visual motion. We recorded the activity of these neurons during a behavioral task in which two monkeys were required to discriminate and remember visual motion presented in the ipsilateral hemifield. During the task, the monkeys viewed two stimuli, sample and test, separated by a brief delay and reported whether they contained motion in the same or in opposite directions. Fifty to 70% of MT neurons were activated by the motion stimuli presented in the ipsilateral hemifield at locations far removed from their classical receptive fields. These responses were in the form of excitation or suppression and were delayed relative to conventional MT responses. Both excitatory and suppressive responses were direction selective, but the nature and the time course of their directionality differed from the conventional excitatory responses recorded with stimuli in the RF. Direction selectivity of the excitatory remote response was transient and early, whereas the suppressive response developed later and persisted after stimulus offset. The presence or absence of these unusual responses on error trials, as well as their magnitude, was affected by the behavioral significance of stimuli used in the task. We hypothesize that these responses represent top-down signals from brain region(s) accessing information about stimuli in the entire visual field and about the behavioral state of the animal. The recruitment of neurons in the opposite hemisphere during processing of behaviorally relevant visual signals reveals a mechanism by which sensory processing can be affected by cognitive task demands.

scholarly journals Postural responses to specific types of long-term memory during visually induced roll self-motion

PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261266
Author(s):  
Maëlle Tixier ◽  
Stéphane Rousset ◽  
Pierre-Alain Barraud ◽  
Corinne Cian
Keyword(s):  
Visual Motion ◽  
Memory Task ◽  
Cognitive Tasks ◽  
Long Term Memory ◽  
Uniform Motion ◽  
Term Memory ◽  
Postural Responses ◽  
Background Motion ◽  
Self Motion

A large body of research has shown that visually induced self-motion (vection) and cognitive processing may interfere with each other. The aim of this study was to assess the interactive effects of a visual motion inducing vection (uniform motion in roll) versus a visual motion without vection (non-uniform motion) and long-term memory processing using the characteristics of standing posture (quiet stance). As the level of interference may be related to the nature of the cognitive tasks used, we examined the effect of visual motion on a memory task which requires a spatial process (episodic recollection) versus a memory task which does not require this process (semantic comparisons). Results confirm data of the literature showing that compensatory postural response in the same direction as background motion. Repeatedly watching visual uniform motion or increasing the cognitive load with a memory task did not decrease postural deviations. Finally, participants were differentially controlling their balance according to the memory task but this difference was significant only in the vection condition and in the plane of background motion. Increased sway regularity (decreased entropy) combined with decreased postural stability (increase variance) during vection for the episodic task would indicate an ineffective postural control. The different interference of episodic and semantic memory on posture during visual motion is consistent with the involvement of spatial processes during episodic memory recollection. It can be suggested that spatial disorientation due to visual roll motion preferentially interferes with spatial cognitive tasks, as spatial tasks can draw on resources expended to control posture.

scholarly journals PITFALLS AND POTENTIALS OF CROWD SCIENCE: A META-ANALYSIS OF CONTEXTUAL INFLUENCES

2015 ◽  
Vol II-3/W5 ◽  
pp. 325-331 ◽  
Author(s):  
A. Klippel ◽  
K. Sparks ◽  
J. O. Wallgrün
Keyword(s):  
Meta Analysis ◽  
Contextual Effects ◽  
Contextual Influences ◽  
Methodological Development ◽  
Behavioral Sciences ◽  
Rigorous Evaluation ◽  
Crowdsourced Data

Crowd science is becoming an integral part of research in many disciplines. The research discussed in this paper lies at the intersection of spatial and behavioral sciences, two of the greatest beneficiaries of crowd science. As a young methodological development, crowd science needs attention from the perspective of a rigorous evaluation of the data collected to explore potentials as well as limitations (pitfalls). Our research has addressed a variety of contextual effects on the validity of crowdsourced data such as cultural, linguistic, regional, as well as methodological differences that we will discuss here in light of semantics.

Re-innervation of axolotl limbs - II. Sensory nerves

1975 ◽  
Vol 190 (1098) ◽  
pp. 59-75 ◽  
Keyword(s):  
Tactile Stimulation ◽  
Receptive Fields ◽  
Sensory Information ◽  
Extracellular Recording ◽  
Sensory Nerves ◽  
Sensory Innervation ◽  
Contralateral Limb ◽  
Innervation Patterns ◽  
Control Limb ◽  
Left And Right

Segmental sensory receptive fields in axolotl hindlimb skin were mapped during extracellular recording of nerve responses to light tactile stimulation. Normally, cutaneous sensory innervation patterns for a given pair of left and right hindlimbs were similar, but there was variability among animals. Individual cutaneous fibres innervated a solitary receptive field whose borders were sharply defined. When spinal nerves were crushed or cut and allowed to regrow the receptive fields re-established were similar to those on the normal contralateral limb. However, many single cutaneous fibres innervated multiple receptive fields. After cutting and interchanging the two major limb nerve branches, regenerating cutaneous nerves tended to innervate skin toward which they were directed, and receptive fields did not resemble the patterns on the control limb skin. This contrasts with the results following the same operations on the motor innervation where patterns of re-innervation do resemble the control. Regenerating cutaneous fibres apparently cannot relocate their respective original cutaneous addresses, but readily re-innervate foreign skin areas. Nerves regenerating after a crush or cut appear to follow mechanical and/or biochemical orienting clues within the nerve trunks for restoration of typical innervation patterns. It is not known how the axolotl central nervous system copes with cutaneous sensory information from mislocated nerve terminals.

Spatial determinants of multisensory integration in cat superior colliculus neurons

1996 ◽  
Vol 75 (5) ◽  
pp. 1843-1857 ◽  
Author(s):  
M. A. Meredith ◽  
B. E. Stein
Keyword(s):  
Receptive Field ◽  
Superior Colliculus ◽  
Neuronal Response ◽  
Receptive Fields ◽  
Spatial Relationship ◽  
Physiological Role ◽  
Extracellular Recording ◽  
Average Proportion ◽  
Relationship Of ◽  
High Degree

1. Although a representation of multisensory space is contained in the superior colliculus, little is known about the spatial requirements of multisensory stimuli that influence the activity of neurons here. Critical to this problem is an assessment of the registry of the different receptive fields within individual multisensory neurons. The present study was initiated to determine how closely the receptive fields of individual multisensory neurons are aligned, the physiological role of that alignment, and the possible functional consequences of inducing receptive-field misalignment. 2. Individual multisensory neurons in the superior colliculus of anesthetized, paralyzed cats were studied with the use of standard extracellular recording techniques. The receptive fields of multisensory neurons were large, as reported previously, but exhibited a surprisingly high degree of spatial coincidence. The average proportion of receptive-field overlap was 86% for the population of visual-auditory neurons sampled. 3. Because of this high degree of intersensory receptive-field correspondence, combined-modality stimuli that were coincident in space tended to fall within the excitatory regions of the receptive fields involved. The result was a significantly enhanced neuronal response in 88% of the multisensory neurons studied. If stimuli were spatially disparate, so that one fell outside its receptive field, either a decreased response occurred (56%), or no intersensory effect was apparent (44%). 4. The normal alignment of the different receptive fields of a multisensory neuron could be disrupted by passively displacing the eyes, pinnae, or limbs/body. In no case was a shift in location or size observed in a neuron's other receptive field(s) to compensate for this displacement. The physiological result of receptive-field misalignment was predictable and based on the location of the stimuli relative to the new positions of their respective receptive fields. Now, for example, one component of a spatially coincident pair of stimuli might fall outside its receptive field and inhibit the other's effects. 5. These data underscore the dependence of multisensory integrative responses on the relationship of the different stimuli to their corresponding receptive fields rather than to the spatial relationship of the stimuli to one another. Apparently, the alignment of different receptive fields for individual multisensory neurons ensures that responses to combinations of stimuli derived from the same event are integrated to increase the salience of that event. Therefore the maintenance of receptive-field alignment is critical for the appropriate integration of converging sensory signals and, ultimately, elicitation of adaptive behaviors.

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