scholarly journals A simple method for creating wide-field visual stimulus for electrophysiology: Mapping and analyzing receptive fields using a hemispheric display

2010 ◽  
Vol 10 (14) ◽  
pp. 15-15 ◽  
Author(s):  
H.-H. Yu ◽  
M. G. P. Rosa
Keyword(s):  
Visual Stimulus ◽  
Receptive Fields ◽  
Wide Field ◽  
Simple Method ◽  
Electrophysiology Mapping

scholarly journals The Regularity of Sustained Firing Reveals Two Populations of Slowly Adapting Touch Receptors in Mouse Hairy Skin

2010 ◽  
Vol 103 (6) ◽  
pp. 3378-3388 ◽  
Author(s):  
Scott A. Wellnitz ◽  
Daine R. Lesniak ◽  
Gregory J. Gerling ◽  
Ellen A. Lumpkin
Keyword(s):  
Fluorescent Protein ◽  
Ex Vivo ◽  
Receptive Fields ◽  
Receptor Subtypes ◽  
Type I ◽  
Genetic Dissection ◽  
Merkel Cells ◽  
Simple Method ◽  
Green Fluorescent ◽  
Nerve Recordings

Touch is initiated by diverse somatosensory afferents that innervate the skin. The ability to manipulate and classify receptor subtypes is prerequisite for elucidating sensory mechanisms. Merkel cell–neurite complexes, which distinguish shapes and textures, are experimentally tractable mammalian touch receptors that mediate slowly adapting type I (SAI) responses. The assessment of SAI function in mutant mice has been hindered because previous studies did not distinguish SAI responses from slowly adapting type II (SAII) responses, which are thought to arise from different end organs, such as Ruffini endings. Thus we sought methods to discriminate these afferent types. We developed an epidermis-up ex vivo skin–nerve chamber to record action potentials from afferents while imaging Merkel cells in intact receptive fields. Using model-based cluster analysis, we found that two types of slowly adapting receptors were readily distinguished based on the regularity of touch-evoked firing patterns. We identified these clusters as SAI (coefficient of variation = 0.78 ± 0.09) and SAII responses (0.21 ± 0.09). The identity of SAI afferents was confirmed by recording from transgenic mice with green fluorescent protein–expressing Merkel cells. SAI receptive fields always contained fluorescent Merkel cells ( n = 10), whereas SAII receptive fields lacked these cells ( n = 5). Consistent with reports from other vertebrates, mouse SAI and SAII responses arise from afferents exhibiting similar conduction velocities, receptive field sizes, mechanical thresholds, and firing rates. These results demonstrate that mice, like other vertebrates, have two classes of slowly adapting light-touch receptors, identify a simple method to distinguish these populations, and extend the utility of skin–nerve recordings for genetic dissection of touch receptor mechanisms.

scholarly journals Binocular Contributions to Optic Flow Processing in the Fly Visual System

2001 ◽  
Vol 85 (2) ◽  
pp. 724-734 ◽  
Author(s):  
Holger G. Krapp ◽  
Roland Hengstenberg ◽  
Martin Egelhaaf
Keyword(s):  
Optic Flow ◽  
Functional Role ◽  
Optic Lobe ◽  
Receptive Fields ◽  
Flow Fields ◽  
Wide Field ◽  
Motion Information ◽  
Local Motion ◽  
Response Field

Integrating binocular motion information tunes wide-field direction-selective neurons in the fly optic lobe to respond preferentially to specific optic flow fields. This is shown by measuring the local preferred directions (LPDs) and local motion sensitivities (LMSs) at many positions within the receptive fields of three types of anatomically identifiable lobula plate tangential neurons: the three horizontal system (HS) neurons, the two centrifugal horizontal (CH) neurons, and three heterolateral connecting elements. The latter impart to two of the HS and to both CH neurons a sensitivity to motion from the contralateral visual field. Thus in two HS neurons and both CH neurons, the response field comprises part of the ipsi- and contralateral visual hemispheres. The distributions of LPDs within the binocular response fields of each neuron show marked similarities to the optic flow fields created by particular types of self-movements of the fly. Based on the characteristic distributions of local preferred directions and motion sensitivities within the response fields, the functional role of the respective neurons in the context of behaviorally relevant processing of visual wide-field motion is discussed.

Orthopteran DCMD neuron: a reevaluation of responses to moving objects. II. Critical cues for detecting approaching objects

1992 ◽  
Vol 68 (5) ◽  
pp. 1667-1682 ◽  
Author(s):  
P. J. Simmons ◽  
F. C. Rind
Keyword(s):  
Moving Objects ◽  
Optic Lobe ◽  
Receptive Fields ◽  
Wide Field ◽  
Motion Detector ◽  
Dark Light ◽  
Subsequent Response ◽  
Object Movement ◽  
Line Movement ◽  
Important Stimulus

1. We examine the critical image cues that are used by the locust visual system for the descending contralateral motion detector (DCMD) neuron to distinguish approaching from receding objects. Images were controlled by computer and presented on an electrostatic monitor. 2. Changes in overall luminance elicited much smaller and briefer responses from the DCMD than objects that appeared to approach the eye. Although a decrease in overall luminance might boost the response to an approaching dark object, movement of edges of the image is more important. 3. When two pairs of lines, in a cross-hairs configuration, were moved apart and then together again, the DCMD showed no preference for divergence compared with convergence of edges. A directional response was obtained by either making the lines increase in extent during divergence and decrease in extent during convergence; or by continually increasing the velocity of line movement during divergence and decreasing velocity during convergence. 4. The DCMD consistently gave a larger response to growing than to shrinking solid rectangular images. An increase compared with a decrease in the extent of edge in an image is, therefore, an important cue for the directionality of the response. For single moving edges of fixed extent, the neuron gave the largest response to edges that subtended 15 degrees at the eye. 5. The DCMD was very sensitive to the amount by which an edge traveled between frames on the display screen, with the largest responses generated by 2.5 degrees of travel. This implies that the neurons in the optic lobe that drive this movement-detecting system have receptive fields of about the same extent as a single ommatidium. 6. For edges moving up to 250 degree/s, the excitation of the DCMD increases with velocity. The response to an edge moving at a constant velocity adapts rapidly, in a manner that depends on velocity. Movement over one part of the retina can adapt the subsequent response to movement over another part of the retina. 7. For the DCMD to track and continue to respond to the image of an approaching object, the edges of the image must continually increase in velocity. This is the second important stimulus cue. 8. Edges of opposite contrasts (light-dark compared with dark-light) are processed in separate pathways that inhibit each other. This would contribute to the reduction of responses to wide-field movements.

Mechanisms of Within- and Cross-Modality Suppression in the Superior Colliculus

1997 ◽  
Vol 78 (6) ◽  
pp. 2834-2847 ◽  
Author(s):  
Daniel C. Kadunce ◽  
J. William Vaughan ◽  
Mark T. Wallace ◽  
Gyorgy Benedek ◽  
Barry E. Stein
Keyword(s):  
Superior Colliculus ◽  
Visual Stimulus ◽  
Receptive Fields ◽  
Specific Interest ◽  
Input Channel ◽  
Modality Effects ◽  
Excitatory Stimulus ◽  
Modality Specificity ◽  
Cat Superior Colliculus ◽  
Close Temporal Proximity

Kadunce, Daniel C., J. William Vaughan, Mark T. Wallace, Gyorgy Benedek, and Barry E. Stein. Mechanisms of within- and cross-modality suppression in the superior colliculus. J. Neurophysiol. 78: 2834–2847, 1997. The present studies were initiated to explore the basis for the response suppression that occurs in cat superior colliculus (SC) neurons when two spatially disparate stimuli are presented simultaneously or in close temporal proximity to one another. Of specific interest was examining the possibility that suppressive regions border the receptive fields (RFs) of unimodal and multisensory SC neurons and, when activated, degrade the neuron's responses to excitatory stimuli. Both within- and cross-modality effects were examined. An example of the former is when a response to a visual stimulus within its RF is suppressed by a second visual stimulus outside the RF. An example of the latter is when the response to a visual stimulus within the visual RF is suppressed when a stimulus from a different modality (e.g., auditory) is presented outside its (i.e., auditory) RF. Suppressive regions were found bordering visual, auditory, and somatosensory RFs. Despite significant modality-specific differences in the incidence and effectiveness of these regions, they were generally quite potent regardless of the modality. In the vast majority (85%) of cases, responses to the excitatory stimulus were degraded by ≥50% by simultaneously stimulating the suppressive region. Contrary to expectations and previous speculations, the effects of activating these suppressive regions often were quite specific. Thus powerful within-modality suppression could be demonstrated in many multisensory neurons in which cross-modality suppression could not be generated. However, the converse was not true. If an extra-RF stimulus inhibited center responses to stimuli of a different modality, it also would suppress center responses to stimuli of its own modality. Thus when cross-modality suppression was demonstrated, it was always accompanied by within-modality suppression. These observations suggest that separate mechanisms underlie within- and cross-modality suppression in the SC. Because some modality-specific tectopetal structures contain neurons with suppressive regions bordering their RFs, the within-modality suppression observed in the SC simply may reflect interactions taking place at the level of one input channel. However, the presence of modality-specific suppression at the level of one input channel would have no effect on the excitation initiated via another input channel. Given the modality-specificity of tectopetal inputs, it appears that cross-modality interactions require the convergence of two or more modality-specific inputs onto the same SC neuron and that the expression of these interactions depends on the internal circuitry of the SC. This allows a cross-modality suppressive signal to be nonspecific and to degrade any and all of the neuron's excitatory inputs.

scholarly journals Self-motion trajectories can facilitate orientation-based figure-ground segregation

2020 ◽  
Vol 123 (3) ◽  
pp. 912-926
Author(s):  
Arkadeb Dutta ◽  
Tidhar Lev-Ari ◽  
Ouriel Barzilay ◽  
Rotem Mairon ◽  
Alon Wolf ◽  
...  
Keyword(s):  
Receptive Fields ◽  
Visual Outcome ◽  
Neural Response ◽  
Head Movements ◽  
Essential Property ◽  
Wide Field ◽  
Tyto Alba ◽  
Dominant Orientation ◽  
Barn Owls ◽  
Detection Of Objects

Segregation of objects from the background is a basic and essential property of the visual system. We studied the neural detection of objects defined by orientation difference from background in barn owls ( Tyto alba). We presented wide-field displays of densely packed stripes with a dominant orientation. Visual objects were created by orienting a circular patch differently from the background. In head-fixed conditions, neurons in both tecto- and thalamofugal visual pathways (optic tectum and visual Wulst) were weakly responsive to these objects in their receptive fields. However, notably, in freely viewing conditions, barn owls occasionally perform peculiar side-to-side head motions (peering) when scanning the environment. In the second part of the study we thus recorded the neural response from head-fixed owls while the visual displays replicated the peering conditions; i.e., the displays (objects and backgrounds) were shifted along trajectories that induced a retinal motion identical to sampled peering motions during viewing of a static object. These conditions induced dramatic neural responses to the objects, in the very same neurons that where unresponsive to the objects in static displays. By reverting to circular motions of the display, we show that the pattern of the neural response is mostly shaped by the orientation of the background relative to motion and not the orientation of the object. Thus our findings provide evidence that peering and/or other self-motions can facilitate orientation-based figure-ground segregation through interaction with inhibition from the surround. NEW & NOTEWORTHY Animals frequently move their sensory organs and thereby create motion cues that can enhance object segregation from background. We address a special example of such active sensing, in barn owls. When scanning the environment, barn owls occasionally perform small-amplitude side-to-side head movements called peering. We show that the visual outcome of such peering movements elicit neural detection of objects that are rotated from the dominant orientation of the background scene and which are otherwise mostly undetected. These results suggest a novel role for self-motions in sensing objects that break the regular orientation of elements in the scene.

Wide-field nondirectional visual units in the pretectum: do they suppress ocular following of saccade-induced visual stimulation

1994 ◽  
Vol 72 (3) ◽  
pp. 1448-1450 ◽  
Author(s):  
M. R. Ibbotson ◽  
R. F. Mark
Keyword(s):  
Visual Stimulation ◽  
Receptive Fields ◽  
Optic Tract ◽  
Inhibitory Input ◽  
Wide Field ◽  
Retinal Slip ◽  
Spatial Frequencies ◽  
Spontaneous Activities ◽  
Ocular Following ◽  
Temporal Stimuli

1. Direction-selective neurons in the nucleus of the optic tract (NOT) provide motion signals for controlling ocular following responses. When stimulated at low temporal and high spatial frequencies of motion (slow speeds), these retinal-slip neurons produce directional responses. When stimulated by motion at high temporal and low spatial frequencies (the visual conditions during saccades) the spontaneous activities of the neurons are inhibited by motion in all directions. A second class of neurons in, or near, the NOT have large receptive fields, are nondirectional, and are tuned to detect the same spatial and temporal stimuli that induce nondirectional inhibition in the retinal-slip neurons. We suggest that the nondirectional cells provide an inhibitory input for the retinal-slip neurons and therefore prevent ocular following of the visual displacements that accompany saccades.

Responses of rabbit superior colliculus neurons to repeated visual stimuli

1975 ◽  
Vol 38 (2) ◽  
pp. 301-312 ◽  
Author(s):  
C. W. Oyster ◽  
E. S. Takahashi
Keyword(s):  
Superior Colliculus ◽  
Visual Stimulus ◽  
Decay Time ◽  
Spontaneous Recovery ◽  
Receptive Fields ◽  
Stimulus Frequency ◽  
Habituation Rate ◽  
Rate Dependent ◽  
Superior Colliculus Neurons ◽  
Made In

It has been shown that cells in the superficial layers of the superior colliculus exhibit response decrements when a visual stimulus is repeated. These response decrements have some of the properties associated with habituation, in particular, 1) spontaneous recovery and 2) habituation rate dependent on stimulus frequency. These observations have been made in two classes of neurons; direction-selective cells and so-called modified concentric cells. All of these neurons had small receptive fields and well-defined response properties. Some neurons in both the direction-selective and modified concentric groups do not show habituation. On the basis of area-threshold curves and other observations, it is suggested that those neurons which habituate possess strong inhibitory inputs which are weak or lacking in thenonhabituating neurons. This generalization leads to a hypothesis that inhibition in the superior colliculus has a long decay time and that a response to a given stimulus is affected by inhibition activated by preceding stimuli.

Neuropsychological Evidence of an Integrated Visuotactile Representation of Peripersonal Space in Humans

1998 ◽  
Vol 10 (5) ◽  
pp. 581-589 ◽  
Author(s):  
Elisabetta Làdavas ◽  
Giuseppe di Pellegrino ◽  
Alessandro Farnè ◽  
Gabriele Zeloni
Keyword(s):  
Visual Stimulus ◽  
Tactile Stimulus ◽  
Right Hemisphere ◽  
Sensory Modality ◽  
Receptive Fields ◽  
Peripersonal Space ◽  
Extrapersonal Space ◽  
Touch Perception ◽  
Neuropsychological Evidence ◽  
Representations Of Space

Current interpretations of extinction suggest that the disorder is due to an unbalanced competition between ipsilesional and contralesional representations of space. The question addressed in this study is whether the competition between left and right representations of space in one sensory modality (i.e., touch) can be reduced or exacerbated by the activation of an intact spatial representation in a different modality that is functionally linked to the damaged representation (i.e., vision). This hypothesis was tested in 10 right-hemisphere lesioned patients who suffered from reliable tactile extinction. We found that a visual stimulus presented near the patient's ipsilesional hand (i.e., visual peripersonal space) inhibited the processing of a tactile stimulus delivered on the contralesional hand (cross-modal visuotactile extinction) to the same extent as did an ipsilesional tactile stimulation (unimodal tactile extinction). It was also found that a visual stimulus presented near the contralesional hand improved the detection of a tactile stimulus applied to the same hand. In striking contrast, less modulatory effects of vision on touch perception were observed when a visual stimulus was presented far from the space immediately around the patient's hand (i.e., extrapersonal space). This study clearly demonstrates the existence of a visual peripersonal space centered on the hand in humans and its modulatory effects on tactile perception. These findings are explained by referring to the activity of bimodal neurons in premotor and parietal cortex of macaque, which have tactile receptive fields on the hand and corresponding visual receptive fields in the space immediately adjacent to the tactile fields.

Center-Surround Interactions in the Middle Temporal Visual Area of the Owl Monkey

2000 ◽  
Vol 84 (5) ◽  
pp. 2658-2669 ◽  
Author(s):  
Richard T. Born
Keyword(s):  
Visual Motion ◽  
Receptive Fields ◽  
Visual Area ◽  
Motion Processing ◽  
Wide Field ◽  
Local Motion ◽  
Middle Temporal ◽  
Visual Motion Processing ◽  
Owl Monkey ◽  
Motion Contrast

Microelectrode recording and 2-deoxyglucose (2dg) labeling were used to investigate center-surround interactions in the middle temporal visual area (MT) of the owl monkey. These techniques revealed columnar groups of neurons whose receptive fields had opposite types of center-surround interaction with respect to moving visual stimuli. In one type of column, neurons responded well to objects such as a single bar or spot but poorly to large textured stimuli such as random dots. This was often due to the fact that the receptive fields had antagonistic surrounds: surround motion in the same direction as that preferred by the center suppressed responses, thus rendering these neurons unresponsive to wide-field motion. In the second set of complementary, interdigitated columns, neuronal receptive fields had reinforcing surrounds and responded optimally to wide-field motion. This functional organization could not be accounted for by systematic differences in binocular disparity. Within both column types, neurons whose receptive fields exhibited center-surround interactions were found less frequently in the input layers compared with the other layers. Additional tests were done on single units to examine the nature of the center-surround interactions. The direction tuning of the surround was broader than that of the center, and the preferred direction, with respect to that of the center, tended to be either in the same or opposite direction and only rarely in orthogonal directions. Surround motion at various velocities modulated the overall responsiveness to centrally placed moving stimuli, but it did not produce shifts in the peaks of the center's tuning curves for either direction or speed. In layers 3B and 5 of the local motion processing columns, a number of neurons responded only to local motion contrast but did so over a region of the visual field that was much larger than the optimal stimulus size. The central feature of this receptive field type was the generalization of surround antagonism over retinotopic space—a property similar to other “complex” receptive fields described previously. The columnar organization of different types of center-surround interactions may reflect the initial segregation of visual motion information into wide-field and local motion contrast systems that serve complementary functions in visual motion processing. Such segregation appears to occur at later stages of the macaque motion processing stream, in the medial superior temporal area (MST), and has also been described in invertebrate visual systems where it appears to be involved in the important function of distinguishing background motion from object motion.

Sign in / Sign up

Export Citation Format

Share Document