Effect of passive eye movement on retinogeniculate transmission in the cat

1990 ◽  
Vol 63 (3) ◽  
pp. 523-538 ◽  
Author(s):  
R. Lal ◽  
M. J. Friedlander
Keyword(s):  
Firing Rate ◽  
Spontaneous Activity ◽  
Eye Movement ◽  
Visual Stimulus ◽  
Action Potentials ◽  
Visual Stimuli ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Visual Response ◽  
Visual Responses ◽  
Movement Effect

1. The nature and time window of interaction between passive phasic eye movement signals and visual stimuli were studied for dorsal lateral geniculate nucleus (LGNd) neurons in the cat. Extracellular recordings were made from single neurons in layer A of the left LGNd of anesthetized paralyzed cats in response to a normalized visual stimulus presented to the right eye at each of several times of movement of the left eye. The left eye was moved passively at a fixed amplitude and velocity while varying the movement onset time with respect to the visual stimulus onset in a randomized and interleaved fashion. Visual stimuli consisted of square-wave modulated circular spots of appropriate contrast, sign, and size to elicit an optimal excitatory response when placed in the neurons' receptive-field (RF) center. 2. Interactions were analyzed for 78 neurons (33 X-neurons, 43 Y-neurons, and 2 physiologically unclassified neurons) on 25-65 trials of identical visual stimuli for each of eight times of eye movement. 3. Sixty percent (47/78) of the neurons tested had a significant eye movement effect (ANOVA, P less than 0.05) on some aspect of their visual response. Of these 47 neurons, 42 (89%) had a significant (P less than 0.05) effect of an appropriately timed eye movement on the number of action potentials, 36 (77%) had a significant effect on the mean peak firing rate, and 31 (66%) were significantly affected as evaluated by both criteria. 4. The eye movement effect on the neurons' visual responses was primarily facilitatory. Facilitation was observed for 37 (79%) of the affected neurons. For 25 of these 37 neurons (68%), the facilitation was significant (P less than 0.05) as evaluated by both criteria (number of action potentials and mean peak firing rate). Ten (21%) of the affected neurons had their visual response significantly inhibited (P less than 0.05). 5. Sixty percent (46/78) of the neurons were tested for the effect of eye movement on both visually elicited activity (visual stimulus contrast = 2 times threshold) and spontaneous activity (contrast = 0). Eye movement significantly affected the visual response of 23 (50%) of these neurons. However, spontaneous activity was significantly affected for only nine (20%) of these neurons. The interaction of the eye movement and visual signals was nonlinear. 6. Nine of 12 neurons (75%) tested had a directionally selective effect of eye movement on the visual response, with most (8/9) preferring the temporal ward direction.(ABSTRACT TRUNCATED AT 400 WORDS)

Effect of passive eye position changes on retinogeniculate transmission in the cat

1990 ◽  
Vol 63 (3) ◽  
pp. 502-522 ◽  
Author(s):  
R. Lal ◽  
M. J. Friedlander
Keyword(s):  
Firing Rate ◽  
Action Potentials ◽  
Visual Stimulation ◽  
Visual Stimuli ◽  
Eye Position ◽  
Visual Response ◽  
Nonlinear Gain ◽  
Physiological Tests ◽  
Normalized Gain ◽  
Stimulation Of

1. Extracellular recordings were made from single neurons in layer A of the left dorsal lateral geniculate nucleus (LGNd) of anesthetized and paralyzed adult cats. Responses to retinotopically identical visual stimuli (presented through the right eye) were recorded at several positions of the left eye in its orbit. Visual stimuli consisted of drifting sinusoidal gratings of optimal temporal and spatial frequencies at twice threshold contrast. Visual stimulation of the left eye was blocked by a variety of methods, including intravitreal injection of tetrodotoxin (TTX). The change in position of the left eye was achieved by passive movements in a randomized and interleaved fashion. Of 237 neurons studied, responses were obtained from 143 neurons on 20-100 trials of identical visual stimulation at each of six eye positions. Neurons were classified as X- or Y- on the basis of a standard battery of physiological tests (primarily linearity of spatial summation and response latency to electrical stimulation of the optic chiasm). 2. The effect of eye position on the visual response of the 143 neurons was analyzed with respect to the number of action potentials elicited and the peak firing rate. Fifty-seven (40%) neurons had a significant effect [by one-factor repeated-measure analysis of variance (ANOVA), P less than 0.05] of eye position on the visual response by either criterion (number of action potentials or peak firing rate). Of these 57 neurons, 47 had a significant effect (P less than 0.05) with respect to the number of action potentials and 23 had a significant effect (P less than 0.05) by both criteria. Thus the permissive measure by either criterion and the conservative measure by both criteria resulted in 40% and 16%, respectively, of all neurons' visual responses being significantly affected by eye position. 3. For the 47 neurons with a significant effect of eye position (number of action potentials criterion), a trend analysis of eye position versus visual response showed a linear trend (P less than 0.05) for 9 neurons, a quadratic trend (P less than 0.05) for 32 neurons, and no significant trend for the 6 remaining neurons. The trends were approximated with linear and nonlinear gain fields (range of eye position change over which the visual response was modulated). The gain fields of individual neurons were compared by measuring the normalized gain (change in neuronal response per degree change of eye position). The mean normalized gain for the 47 neurons was 4.3. 4. The nonlinear gain fields were generally symmetric with respect to nasal versus temporal changes in eye position.(ABSTRACT TRUNCATED AT 400 WORDS)

Effect of longer periods of dark rearing on NMDA receptors in cat visual cortex

1994 ◽  
Vol 72 (3) ◽  
pp. 1220-1226 ◽  
Author(s):  
D. Czepita ◽  
S. N. Reid ◽  
N. W. Daw
Keyword(s):  
Visual Cortex ◽  
Nmda Receptor ◽  
Firing Rate ◽  
Spontaneous Activity ◽  
Visual Response ◽  
Visual Responses ◽  
Level Of Activity ◽  
Direction Of Movement ◽  
Excitatory Drive ◽  
Dark Rearing

1. Cats were reared in the dark to 3, 5, and 11 mo. We studied the N-methyl-D-aspartate (NMDA) receptor contribution to the visual response in the cortex, defined as the percentage reduction in visual response after application of 2-amino-5-phosphonovaleric acid (APV). We also studied the firing rate in response to the optimal visual stimulus and the spontaneous activity. We made comparisons of all these properties between light-reared and dark-reared animals. 2. The NMDA receptor contribution to the visual response in layers IV, V, and VI of dark-reared animals was substantially above that in light-reared animals at all ages tested. 3. The specificity of receptive field properties in dark-reared animals showed some degeneration between 6 wk and 3 mo of age. At > or = 3 mo, almost no cells were specific for orientation and direction of movement. 4. Firing rate was lower in dark-reared animals at all ages, suggesting a decrease in excitatory drive to the visual cortex. 5. Spontaneous activity was equal in dark- and light-reared animals, suggesting that the overall level of activity (including visual responses as well as spontaneous activity) in light-reared animals is higher than in dark-reared animals. This should tend to upregulate glutamate receptors in general in dark-reared animals.

Visual responses of inferior temporal neurons in awake rhesus monkey

1983 ◽  
Vol 50 (6) ◽  
pp. 1415-1432 ◽  
Author(s):  
B. J. Richmond ◽  
R. H. Wurtz ◽  
T. Sato
Keyword(s):  
Visual Stimulus ◽  
Visual Stimuli ◽  
Stimulus Presentation ◽  
Visual Response ◽  
Visual Responses ◽  
Transient Time ◽  
Best Response ◽  
Complex Stimuli ◽  
Fixation Task ◽  
Area Te

We studied the responses to visual stimuli of neurons in area TE of the inferior temporal (IT) cortex in four awake monkeys (Macaca mulatta) trained to perform behavioral tasks. While the monkey looked at a fixation point in order to detect its dimming, another stimulus, such as a spot of light or a sine- or square-wave grating, usually produced only slight responses in inferior temporal neurons. However, the response to the stimulus was more vigorous if the task was changed so the fixation point blinked off before the stimulus came on while the monkey maintained its gaze. Responses to visual stimuli during this blink task were seen in 199 of 288 cells studied, and nearly all responded to a visual stimulus better during the blink task than during the task in which the fixation point remained on. Small spots of light usually produced consistent responses; we did not explore the response to complex stimuli or to objects. Latency of the visual response ranged from 70 to 220 ms. While the response of cells to a stimulus in the presence of the fixation point was limited to areas near the fovea, this apparently constricted visual receptive field expanded during the blink of the fixation point. In order to determine whether the increased response of the cell in the absence of the fixation point was due to a shift of attention from the fixation point to the visual stimulus, we required the monkey to respond to the dimming of this stimulus rather than to the dimming of the fixation point. We found that attention to the visual stimulus decreased the response of the cell during both the fixation and blink tasks. That is, the best response to the stimulus occurred in the blink task when attention to the stimulus was not required, while the poorest response occurred in the fixation task when attention to the stimulus was required. The reappearance of the fixation point during stimulus presentation in the blink task caused a transient time-locked suppression of response to the stimulus. This suggests that the reduction of response to the stimulus in the presence of the fixation point is caused by an interaction between the responses to the fixation point and the visual stimulus. To insure that we were recording from the same population of cells that had first been characterized by Gross, Rocha-Miranda, and Bender (14) in anesthetized, paralyzed monkeys, we recorded under those same conditions in two of our four monkeys.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals Melanopsin-driven increases in maintained activity enhance thalamic visual response reliability across a simulated dawn

2015 ◽  
Vol 112 (42) ◽  
pp. E5734-E5743 ◽  
Author(s):  
Riccardo Storchi ◽  
Nina Milosavljevic ◽  
Cyril G. Eleftheriou ◽  
Franck P. Martial ◽  
Patrycja Orlowska-Feuer ◽  
...  
Keyword(s):  
Light Intensity ◽  
Lateral Geniculate Nucleus ◽  
Visual Stimuli ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Visual Response ◽  
Visual Responses ◽  
Silent Substitution ◽  
Background Light ◽  
Lateral Geniculate ◽  
Dorsal Lateral Geniculate

Twice a day, at dawn and dusk, we experience gradual but very high amplitude changes in background light intensity (irradiance). Although we perceive the associated change in environmental brightness, the representation of such very slow alterations in irradiance by the early visual system has been little studied. Here, we addressed this deficit by recording electrophysiological activity in the mouse dorsal lateral geniculate nucleus under exposure to a simulated dawn. As irradiance increased we found a widespread enhancement in baseline firing that extended to units with ON as well as OFF responses to fast luminance increments. This change in baseline firing was equally apparent when the slow irradiance ramp appeared alone or when a variety of higher-frequency artificial or natural visual stimuli were superimposed upon it. Using a combination of conventional knockout, chemogenetic, and receptor-silent substitution manipulations, we continued to show that, over higher irradiances, this increase in firing originates with inner-retinal melanopsin photoreception. At the single-unit level, irradiance-dependent increases in baseline firing were strongly correlated with improvements in the amplitude of responses to higher-frequency visual stimuli. This in turn results in an up to threefold increase in single-trial reliability of fast visual responses. In this way, our data indicate that melanopsin drives a generalized increase in dorsal lateral geniculate nucleus excitability as dawn progresses that both conveys information about changing background light intensity and increases the signal:noise for fast visual responses.

scholarly journals Visual response of ventrolateral prefrontal neurons and their behavior-related modulation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Stefano Rozzi ◽  
Marco Bimbi ◽  
Alfonso Gravante ◽  
Luciano Simone ◽  
Leonardo Fogassi
Keyword(s):  
Visual Cues ◽  
Visual Stimuli ◽  
Visual Response ◽  
Visual Responses ◽  
Action Execution ◽  
Natural Behavior ◽  
Large Sector ◽  
Small Set ◽  
Early Passive ◽  
Task Conditions

AbstractThe ventral part of lateral prefrontal cortex (VLPF) of the monkey receives strong visual input, mainly from inferotemporal cortex. It has been shown that VLPF neurons can show visual responses during paradigms requiring to associate arbitrary visual cues to behavioral reactions. Further studies showed that there are also VLPF neurons responding to the presentation of specific visual stimuli, such as objects and faces. However, it is largely unknown whether VLPF neurons respond and differentiate between stimuli belonging to different categories, also in absence of a specific requirement to actively categorize or to exploit these stimuli for choosing a given behavior. The first aim of the present study is to evaluate and map the responses of neurons of a large sector of VLPF to a wide set of visual stimuli when monkeys simply observe them. Recent studies showed that visual responses to objects are also present in VLPF neurons coding action execution, when they are the target of the action. Thus, the second aim of the present study is to compare the visual responses of VLPF neurons when the same objects are simply observed or when they become the target of a grasping action. Our results indicate that: (1) part of VLPF visually responsive neurons respond specifically to one stimulus or to a small set of stimuli, but there is no indication of a “passive” categorical coding; (2) VLPF neuronal visual responses to objects are often modulated by the task conditions in which the object is observed, with the strongest response when the object is target of an action. These data indicate that VLPF performs an early passive description of several types of visual stimuli, that can then be used for organizing and planning behavior. This could explain the modulation of visual response both in associative learning and in natural behavior.

Receiver operating characteristic (ROC) analysis of neurons in the cat's lateral geniculate nucleus during tonic and burst response mode

1995 ◽  
Vol 12 (4) ◽  
pp. 723-741 ◽  
Author(s):  
W. Guido ◽  
S.-M. Lu ◽  
J.W. Vaughan ◽  
Dwayne W. Godwin ◽  
S. Murray Sherman
Keyword(s):  
Visual Stimulus ◽  
Action Potentials ◽  
Operating Characteristic ◽  
Visual Stimuli ◽  
Roc Curves ◽  
Response Mode ◽  
Burst Mode ◽  
Low Threshold Spike ◽  
Low Threshold ◽  
Roc Area

AbstractRelay cells of the lateral geniculate nucleus respond to visual stimuli in one of two modes: burst and tonic. The burst mode depends on the activation of a voltage-dependent, Ca2+ conductance underlying the low threshold spike. This conductance is inactivated at depolarized membrane potentials, but when activated from hyperpolarized levels, it leads to a large, triangular, nearly all-or-none depolarization. Typically, riding its crest is a high-frequency barrage of action potentials. Low threshold spikes thus provide a nonlinear amplification allowing hyperpolarized relay neurons to respond to depolarizing inputs, including retinal EPSPs. In contrast, the tonic mode is characterized by a steady stream of unitary action potentials that more linearly reflects the visual stimulus. In this study, we tested possible differences in detection between response modes of 103 geniculate neurons by constructing receiver operating characteristic (ROC) curves for responses to visual stimuli (drifting sine-wave gratings and flashing spots). Detectability was determined from the ROC curves by computing the area under each curve, known as the ROC area. Most cells switched between modes during recording, evidently due to small shifts in membrane potential that affected the activation state of the low threshold spike. We found that the more often a cell responded in burst mode, the larger its ROC area. This was true for responses to optimal and nonoptimal visual stimuli, the latter including nonoptimal spatial frequencies and low stimulus contrasts. The larger ROC areas associated with burst mode were due to a reduced spontaneous activity and roughly equivalent level of visually evoked response when compared to tonic mode. We performed a within-cell analysis on a subset of 22 cells that switched modes during recording. Every cell, whether tested with a low contrast or high contrast visual stimulus exhibited a larger ROC area during its burst response mode than during its tonic mode. We conclude that burst responses better support signal detection than do tonic responses. Thus, burst responses, while less linear and perhaps less useful in providing a detailed analysis of visual stimuli, improve target detection. The tonic mode, with its more linear response, seems better suited for signal analysis rather than signal detection.

scholarly journals Pure tones modulate the representation of orientation and direction in the primary visual cortex

2019 ◽  
Vol 121 (6) ◽  
pp. 2202-2214 ◽  
Author(s):  
John P. McClure ◽  
Pierre-Olivier Polack
Keyword(s):  
Visual Cortex ◽  
Primary Visual Cortex ◽  
Visual Stimulus ◽  
Visual Stimuli ◽  
Direction Selectivity ◽  
Multimodal Integration ◽  
Visual Responses ◽  
V1 Neurons ◽  
Pure Tones ◽  
The Impact

Multimodal sensory integration facilitates the generation of a unified and coherent perception of the environment. It is now well established that unimodal sensory perceptions, such as vision, are improved in multisensory contexts. Whereas multimodal integration is primarily performed by dedicated multisensory brain regions such as the association cortices or the superior colliculus, recent studies have shown that multisensory interactions also occur in primary sensory cortices. In particular, sounds were shown to modulate the responses of neurons located in layers 2/3 (L2/3) of the mouse primary visual cortex (V1). Yet, the net effect of sound modulation at the V1 population level remained unclear. In the present study, we performed two-photon calcium imaging in awake mice to compare the representation of the orientation and the direction of drifting gratings by V1 L2/3 neurons in unimodal (visual only) or multimodal (audiovisual) conditions. We found that sound modulation depended on the tuning properties (orientation and direction selectivity) and response amplitudes of V1 L2/3 neurons. Sounds potentiated the responses of neurons that were highly tuned to the cue’s orientation and direction but weakly active in the unimodal context, following the principle of inverse effectiveness of multimodal integration. Moreover, sound suppressed the responses of neurons untuned for the orientation and/or the direction of the visual cue. Altogether, sound modulation improved the representation of the orientation and direction of the visual stimulus in V1 L2/3. Namely, visual stimuli presented with auditory stimuli recruited a neuronal population better tuned to the visual stimulus orientation and direction than when presented alone. NEW & NOTEWORTHY The primary visual cortex (V1) receives direct inputs from the primary auditory cortex. Yet, the impact of sounds on visual processing in V1 remains controverted. We show that the modulation by pure tones of V1 visual responses depends on the orientation selectivity, direction selectivity, and response amplitudes of V1 neurons. Hence, audiovisual stimuli recruit a population of V1 neurons better tuned to the orientation and direction of the visual stimulus than unimodal visual stimuli.

Neurons in the cat pretectum that project to the dorsal lateral geniculate nucleus are activated during saccades

1996 ◽  
Vol 76 (5) ◽  
pp. 2907-2918 ◽  
Author(s):  
M. Schmidt
Keyword(s):  
Eye Movements ◽  
Lateral Geniculate Nucleus ◽  
Visual Stimulus ◽  
Visual Stimuli ◽  
Saccadic Eye Movements ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Response Latencies ◽  
Retinal Slip ◽  
Response Properties ◽  
Dorsal Lateral Geniculate

1. Neurons in the pretectal nuclear complex that project to the ipsilateral dorsal lateral geniculate nucleus (LGNd) were identified by antidromic activation after electrical LGNd stimulation in awake cats, and their response properties were characterized to retinal image shifts elicited either by external visual stimulus movements or during spontaneous saccadic eye movements on a stationary visual stimulus, and to saccades in darkness. Eye position was monitored with the use of a scleral search coil and care was taken to assure stability of the eyes during presentation of moving visual stimuli. 2. Of a total sample of 134 cells recorded, 27 neurons were antidromically activated by electrical LGNd stimulation. In addition, responses from neurons that were not activated from the LGNd were also analyzed, including 19 “retinal slip” cells, which selectively respond to slow horizontal stimulus movements, and 21 “jerk” cells, which are specifically activated by rapid stimulus shifts. All recorded neurons were located in the nucleus of the optic tract and in the posterior pretectal nucleus. 3. In the light, neurons identified as projecting to the LGNd responded maximally to saccadic eye movements and to externally generated sudden shifts of large visual stimuli. Slow stimulus drifts did not activate these neurons. Response latencies were shorter and peak activities were increased during saccades compared with pure visual stimulation. No systematic correlation between response latency, response duration, or the number of spikes in the response and saccade direction, saccade amplitude, or saccade duration was found. Saccades and rapid stimulus shifts in the light also activated jerk cells but not retinal slip cells. 4. All 27 antidromically activated neurons also responded to spontaneous saccadic eye movements in complete darkness. Responses to saccades in the dark, however, had longer response latencies and lower peak activities than responses to saccades in light. As in the light, response parameters in darkness seemed not to code specific saccade parameters. Cells that were not activated from LGNd were found to be unresponsive to saccades in the dark. 5. According to their specific activation by saccades in darkness, LGNd-projecting pretectal neurons are termed “saccade neurons” to distinguish them from other pretectal cell populations, in particular from jerk neurons, which show similar response properties in light. 6. The saccade-related activation of pretectal saccade neurons may be used to modulate visual responses of LGNd relay cells following saccadic eye movements. Because the pretectogeniculate projection in cat most likely is GABAergic and terminates on inhibitory LGNd interneurons, its activation may lead to a saccade-locked disinhibition of relay cells. This input could counter the strong inhibition induced in the LGNd after shifts of gaze direction and lead to a resetting of LGNd cell activity.

Dependence of retinogeniculate transmission in cat on NMDA receptors

1990 ◽  
Vol 63 (2) ◽  
pp. 347-355 ◽  
Author(s):  
A. M. Sillito ◽  
P. C. Murphy ◽  
T. E. Salt ◽  
C. I. Moody
Keyword(s):  
Nmda Receptor ◽  
Nmda Receptors ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Visual Response ◽  
Visual Responses ◽  
Receptor Agonists ◽  
Selective Blockade ◽  
X And Y Cells ◽  
X 24 ◽  
Y Cells

1. We have examined the possibility that N-methyl-D-aspartate (NMDA) receptors may be involved in the visual response of relay cells in the cat dorsal lateral geniculate nucleus (dLGN). The selective NMDA receptor antagonists D-2-amino-5-phosphonovalerate (APV) and 3-[(+/-)-2-carboxypiperazin-4-yl]-propyl-1-phosphonic acid (CPP) have been iontophoretically applied to X and Y cells in the dLGN and their effects on the visual response to a light spot flashed within the receptive field center determined. 2. The antagonist effects were assessed at ejection current levels producing a selective blockade of the responses to iontophoretically applied NMDA with respect to those elicited by the non-NMDA receptor agonists quisqualate and kainate. These selective effects were determined in an experimental paradigm where the visual response and responses to NMDA and the non-NMDA receptor agonists were compared in the same test run. The data refer to a total population of 52 cells (28 X, 24 Y). 3. Application of APV abolished or greatly reduced the visual responses of both X and Y cells. The mean percentage reduction in the visual response for the X cells studied was 59 +/- 10% (SE; n = 7) and for the Y cells 66 +/- 8% (SE; n = 11). Both the early onset transient and the sustained component of the visual response to the flashed stimulus were equally affected. 4. The antagonist CPP produced a similar pattern of effect to APV, substantially reducing or abolishing the visual response in both X and Y cells.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Low-Frequency Oscillations Arising From Competitive Interactions Between Visual Stimuli in Macaque Inferotemporal Cortex

2005 ◽  
Vol 94 (5) ◽  
pp. 3368-3387 ◽  
Author(s):  
Julianne E. Rollenhagen ◽  
Carl R. Olson
Keyword(s):  
Action Potentials ◽  
Visual Stimuli ◽  
Low Frequency ◽  
Macaque Monkey ◽  
Competitive Interactions ◽  
Visual Responses ◽  
Inferotemporal Cortex ◽  
Excitatory Response ◽  
Neuronal Populations ◽  
Low Frequency Oscillations

Some neurons in the inferotemporal cortex (IT) of the macaque monkey respond to visual stimuli by firing action potentials in a series of sharply defined bursts at a frequency of about 5 Hz. The aim of the present study was to test the hypothesis that the oscillatory responses of these neurons depend on competitive interactions with other neurons selective for different stimuli. To test this hypothesis, we monitored responses to probe images displayed in the presence of other already visible backdrop images. Two stimuli were used in testing each neuron: a foveal image that, when displayed alone, elicited an excitatory response (the “object”) and a peripheral image that, when displayed alone, elicited little or no activity (the “flanker”). We assessed the results of presenting these images separately and together in monkeys trained to maintain central fixation. Two novel phenomena emerged. First, displaying the object in the presence of the flanker enhanced the strength of the oscillatory component of the response to the object. This effect varied in strength across task contexts and may have depended on the monkey's allocating attention to the flanker. Second, displaying the flanker in the presence of the object gave rise to sometimes strong oscillations in which the initial phase was negative. This was all the more striking because the flanker by itself elicited little or no response. This effect was robust and invariant across task contexts. These results can be accounted for by competition between two neuronal populations, one selective for the object and the other for the flanker, if it is assumed that the visual responses of each population are subject to fatigue.

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