Time Course of Attentional Modulation in the Frontal Eye Field During Curve Tracing

2009 ◽  
Vol 101 (4) ◽  
pp. 1813-1822 ◽  
Author(s):  
P. S. Khayat ◽  
A. Pooresmaeili ◽  
P. R. Roelfsema
Keyword(s):  
Visual Information ◽  
Time Course ◽  
Stimulus Presentation ◽  
Frontal Eye Field ◽  
Stimulus Selection ◽  
Visual Response ◽  
Visual Responses ◽  
Cortical Regions ◽  
Visual Cortical ◽  
Curve Tracing

Neurons in the frontal eye fields (FEFs) register incoming visual information and select visual stimuli that are relevant for behavior. Here we investigated the timing of the visual response and the timing of selection by recording from single FEF neurons in a curve-tracing task that requires shifts of attention followed by an oculomotor response. We found that the behavioral selection signal in area FEF had a latency of 147 ms and that it was delayed substantially relative to the visual response, which occurred 50 ms after stimulus presentation. We compared the FEF responses to activity previously recorded in the primary visual cortex (area V1) during the same task. Visual responses in area V1 preceded the FEF responses, but the latencies of selection signals in areas V1 and FEF were similar. The similarity of timing of selection signals in structures at opposite ends of the visual cortical processing hierarchy supports the view that stimulus selection occurs in an interaction between widely separated cortical regions.

Signal Timing Across the Macaque Visual System

1998 ◽  
Vol 79 (6) ◽  
pp. 3272-3278 ◽  
Author(s):  
Matthew T. Schmolesky ◽  
Youngchang Wang ◽  
Doug P. Hanes ◽  
Kirk G. Thompson ◽  
Stefan Leutgeb ◽  
...  
Keyword(s):  
Visual System ◽  
Visual Processing ◽  
Time Course ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Frontal Eye Field ◽  
Signal Timing ◽  
Visual Response ◽  
Visual Responses ◽  
Response Latencies ◽  
Temporal Area

Schmolesky, Matthew T., Youngchang Wang, Doug P. Hanes, Kirk G. Thompson, Stefan Leutgeb, Jeffrey D. Schall, and Audie G. Leventhal. Signal timing across the macaque visual system. J. Neurophysiol. 79: 3272–3278, 1998. The onset latencies of single-unit responses evoked by flashing visual stimuli were measured in the parvocellular (P) and magnocellular (M) layers of the dorsal lateral geniculate nucleus (LGNd) and in cortical visual areas V1, V2, V3, V4, middle temporal area (MT), medial superior temporal area (MST), and in the frontal eye field (FEF) in individual anesthetized monkeys. Identical procedures were carried out to assess latencies in each area, often in the same monkey, thereby permitting direct comparisons of timing across areas. This study presents the visual flash-evoked latencies for cells in areas where such data are common (V1 and V2), and are therefore a good standard, and also in areas where such data are sparse (LGNd M and P layers, MT, V4) or entirely lacking (V3, MST, and FEF in anesthetized preparation). Visual-evoked onset latencies were, on average, 17 ms shorter in the LGNd M layers than in the LGNd P layers. Visual responses occurred in V1 before any other cortical area. The next wave of activation occurred concurrently in areas V3, MT, MST, and FEF. Visual response latencies in areas V2 and V4 were progressively later and more broadly distributed. These differences in the time course of activation across the dorsal and ventral streams provide important temporal constraints on theories of visual processing.

A collicular visual cortex: Neocortical space for an ancient midbrain visual structure

Science ◽  
2019 ◽  
Vol 363 (6422) ◽  
pp. 64-69 ◽  
Author(s):  
Riccardo Beltramo ◽  
Massimo Scanziani
Keyword(s):  
Cerebral Cortex ◽  
Visual Cortex ◽  
Primary Visual Cortex ◽  
Visual Information ◽  
Cortical Area ◽  
Moving Objects ◽  
Visual Responses ◽  
Visual Cortical Area ◽  
Postrhinal Cortex ◽  
Visual Cortical

Visual responses in the cerebral cortex are believed to rely on the geniculate input to the primary visual cortex (V1). Indeed, V1 lesions substantially reduce visual responses throughout the cortex. Visual information enters the cortex also through the superior colliculus (SC), but the function of this input on visual responses in the cortex is less clear. SC lesions affect cortical visual responses less than V1 lesions, and no visual cortical area appears to entirely rely on SC inputs. We show that visual responses in a mouse lateral visual cortical area called the postrhinal cortex are independent of V1 and are abolished upon silencing of the SC. This area outperforms V1 in discriminating moving objects. We thus identify a collicular primary visual cortex that is independent of the geniculo-cortical pathway and is capable of motion discrimination.

scholarly journals Neural mechanisms of speed-accuracy tradeoff of visual search: Saccade vigor, targeting errors, superior colliculus and frontal eye field

2017 ◽  
Author(s):  
Thomas R. Reppert ◽  
Mathieu Servant ◽  
Richard P. Heitz ◽  
Jeffrey D. Schall
Keyword(s):  
Visual Search ◽  
Superior Colliculus ◽  
Time Course ◽  
Frontal Eye Field ◽  
Visual Responses ◽  
Response Preparation ◽  
Eye Field ◽  
Neurophysiological Mechanisms ◽  
Speed Accuracy ◽  
Accuracy Tradeoff

AbstractBalancing the speed-accuracy tradeoff (SAT) is necessary for successful behavior. Using a visual search task with interleaved cues emphasizing speed or accuracy, we recently reported diverse contributions of frontal eye field (FEF) neurons instantiating salience evidence and response preparation. Here we report replication of visual search SAT performance in two macaque monkeys, new information about variation of saccade dynamics with SAT, extension of the neurophysiological investigation to describe processes in the superior colliculus, and description of the origin of search errors in this task. Saccade vigor varied idiosyncratically across SAT conditions and monkeys, but tended to decrease with response time. As observed in the FEF, speed-accuracy tradeoff was accomplished through several distinct adjustments in the superior colliculus. Visually-responsive neurons modulated baseline firing rate and the time course of salience evidence. Unlike FEF, the magnitude of visual responses in SC did not vary across SAT conditions, but the time to locate the target was longer in Accurate as compared to Fast trials. Also unlike FEF, the activity of SC movement neurons when saccades were initiated was equivalent in Fast and Accurate trials. Search errors occurred when visual salience neurons in FEF and SC treated distractors as targets, even in the Accurate condition. Saccade-related neural activity in SC but less FEF varied with saccade peak velocity. These results extend our understanding of the cortical and subcortical contributions to SAT.Significance statementNeurophysiological mechanisms of speed-accuracy tradeoff (SAT) have only recently been investigated. This paper reports the first replication of SAT performance in nonhuman primates, the first report of variation of saccade dynamics with SAT, the first description of superior colliculus contributions to SAT, and the first description of the origin of errors during SAT. These results inform and constrain new models of distributed decision-making.

Effects of serotonin on retinotectal-, corticotectal-, and glutamate-induced activity in the superior colliculus of the hamster

1993 ◽  
Vol 70 (2) ◽  
pp. 723-732 ◽  
Author(s):  
X. Huang ◽  
R. D. Mooney ◽  
R. W. Rhoades
Keyword(s):  
Superior Colliculus ◽  
Optic Chiasm ◽  
Superficial Layer ◽  
Response Suppression ◽  
Visual Response ◽  
Evoked Responses ◽  
Average Response ◽  
Visual Responses ◽  
Unit Recording ◽  
Visual Cortical

1. Single-unit recording and iontophoretic techniques were used to test the effects of serotonin (5-HT) on the responses of neurons in the superficial layers (the stratum griseum superficiale and stratum opticum) of the hamster's superior colliculus (SC). 2. Iontophoresis of 5-HT produced a visual response suppression of 40% or greater in 78.1% (n = 50) of 64 neurons tested. 5-HT did not augment the visual responses of any of the cells tested. The average response suppression was 75.3 +/- 21.2% (mean +/- S.D.). 3. Iontophoresis of 5-HT had significantly different effects on activation of SC cells by optic chiasm (OX) and visual cortical (CTX) stimulation. Application of 5-HT suppressed the OX-evoked responses of 96.9% (n = 31) of the 32 SC cells tested by at least 40%, and the average response suppression for all 32 neurons tested was 87.1 +/- 22.5%. Application of 5-HT suppressed the responses of only 35.7% (n = 10) of the 28 cells tested with CTX stimulation by at least 40%. The average response suppression for all 28 cells was 35.3 +/- 38.8%. 4. The effects of 5-HT on the glutamate-evoked responses of SC cells that were synaptically "isolated" by concurrent application of Mg2+ were also evaluated. Application of 5-HT produced a response suppression > or = 40% in 29.7% (n = 19) of the 64 neurons tested under these conditions. The average response suppression for all of the cells tested was 28.4 +/- 35.7%. This effect of 5-HT was significantly weaker than that on visually evoked responses of these neurons. 5. The present results demonstrate that 5-HT markedly depresses the visual responses of most superficial layer SC neurons. They suggest further that much of this effect is mediated by presynaptic inhibition of retinotectal transmission.

scholarly journals Integration of Eye-Centered and Landmark-Centered Codes in Frontal Eye Field Gaze Responses

2020 ◽  
Vol 30 (9) ◽  
pp. 4995-5013 ◽  
Author(s):  
Vishal Bharmauria ◽  
Amirsaman Sajad ◽  
Jirui Li ◽  
Xiaogang Yan ◽  
Hongying Wang ◽  
...  
Keyword(s):  
Frontal Cortex ◽  
Visual Information ◽  
Target Position ◽  
Frontal Eye Field ◽  
Visual Responses ◽  
Cellular Mechanisms ◽  
Behavioral Experiments ◽  
The Gaze ◽  
Field Activity ◽  
Eye Field

Abstract The visual system is thought to separate egocentric and allocentric representations, but behavioral experiments show that these codes are optimally integrated to influence goal-directed movements. To test if frontal cortex participates in this integration, we recorded primate frontal eye field activity during a cue-conflict memory delay saccade task. To dissociate egocentric and allocentric coordinates, we surreptitiously shifted a visual landmark during the delay period, causing saccades to deviate by 37% in the same direction. To assess the cellular mechanisms, we fit neural response fields against an egocentric (eye-centered target-to-gaze) continuum, and an allocentric shift (eye-to-landmark-centered) continuum. Initial visual responses best-fit target position. Motor responses (after the landmark shift) predicted future gaze position but embedded within the motor code was a 29% shift toward allocentric coordinates. This shift appeared transiently in memory-related visuomotor activity, and then reappeared in motor activity before saccades. Notably, fits along the egocentric and allocentric shift continua were initially independent, but became correlated across neurons just before the motor burst. Overall, these results implicate frontal cortex in the integration of egocentric and allocentric visual information for goal-directed action, and demonstrate the cell-specific, temporal progression of signal multiplexing for this process in the gaze system.

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)

Dissociation of Visual Discrimination From Saccade Programming in Macaque Frontal Eye Field

1997 ◽  
Vol 77 (2) ◽  
pp. 1046-1050 ◽  
Author(s):  
Kirk G. Thompson ◽  
Narcisse P. Bichot ◽  
Jeffrey D. Schall
Keyword(s):  
Visual Search ◽  
Eye Movements ◽  
Visual Stimulus ◽  
Visual Discrimination ◽  
Time Course ◽  
Selection Process ◽  
Frontal Eye Field ◽  
Visual Responses ◽  
Eye Field ◽  
Saccade Programming

Thompson, Kirk G., Narcisse P. Bichot, and Jeffrey D. Schall. Dissociation of visual discrimination from saccade programming in macaque frontal eye field. J. Neurophysiol. 77: 1046–1050, 1997. To determine whether visual discrimination in macaque frontal eye field (FEF) is contingent on saccade planning, unit activity was recorded in two monkeys during blocked go and no-go visual search trials. The eye movements made by monkeys after correct no-go trials, in addition to an attenuation of the visual responses in no-go trials compared with go trials, indicated that covert saccade planning was effectively discouraged. During no-go search trials, the activity of the majority of neurons evolved to signal the location of the oddball stimulus. The degree and time course of the stimulus discrimination process observed in no-go trials was not different from that observed in go trials. We conclude that the discrimination of a salient visual stimulus reflected by FEF neurons is not contingent on saccade production but rather may reflect the outcome of an automatic visual selection process.

Hunger and satiety modify the responses of olfactory and visual neurons in the primate orbitofrontal cortex

1996 ◽  
Vol 75 (4) ◽  
pp. 1673-1686 ◽  
Author(s):  
H. D. Critchley ◽  
E. T. Rolls
Keyword(s):  
Orbitofrontal Cortex ◽  
Visual Information ◽  
Specific Effect ◽  
Visual Responses ◽  
Olfactory Neurons ◽  
Visual Neurons ◽  
Visual Areas ◽  
Before And After ◽  
Cortical Regions ◽  
Gustatory Neurons

1. The primate orbitofrontal cortex is the site of convergence of information from primary taste and primary olfactory cortical regions. In addition, it receives projections from temporal lobe visual areas concerned with the representation of objects such as foods. Previous work has shown that the responses of gustatory neurons in the secondary taste area within the orbitofrontal cortex are modulated by hunger and satiety, in that they stop responding to the taste of a food on which an animal has been fed to behavioral satiation, yet may continue to respond to the taste of other foods. 2. This study demonstrates a similar modulation of the responses of olfactory and visual orbitofrontal cortex neurons after feeding to satiety. Seven of nine olfactory neurons that were responsive to the odors of foods, such as blackcurrant juice, were found to decrease their responses to the odor of the satiating food in a selective and statistically significant manner. 3. It also was found for eight of nine neurons that had selective responses to the sight of food, that they demonstrated a sensory-specific reduction in their visual responses to foods after satiation. 4. The responses of orbitofrontal cortex neurons selective for foods in more than one modality also were analyzed before and after feeding to satiation. Satiety often affected the responses of these multimodal neurons across all modalities, but a sensory-specific effect was not always demonstrable for both modalities. 5. These findings show that the olfactory and visual representations of food, as well as the taste representation of food, in the primate orbitofrontal cortex are modulated by hunger. Usually a component related to sensory-specific satiety can be demonstrated. The findings link at least part of the processing of olfactory and visual information in this brain region to the control of feeding-related behavior.

Spatial Processing in the Monkey Frontal Eye Field. I. Predictive Visual Responses

1997 ◽  
Vol 78 (3) ◽  
pp. 1373-1383 ◽  
Author(s):  
Marc M. Umeno ◽  
Michael E. Goldberg
Keyword(s):  
Receptive Field ◽  
Visual Processing ◽  
Target Position ◽  
Spatial Processing ◽  
Explicit Calculation ◽  
Frontal Eye Field ◽  
Visual Response ◽  
Visual Responses ◽  
Visual Cells ◽  
Eye Field

Umeno, M. M. and Goldberg, M. E. Spatial processing in the monkey frontal eye field. I. Predictive visual responses. J. Neurophysiol. 78: 1373–1383, 1997. Neurons in the lateral intraparietal area and intermediate layers of the superior colliculus show predictive visual responses. They respond before an impending saccade to a stimulus that will be brought into their receptive field by that saccade. In these experiments we sought to establish whether the monkey frontal eye field had a similar predictive response. We recorded from 100 presaccadic frontal eye field neurons (32 visual cells, 48 visuomovement cells, and 20 movement cells) with the use of the classification criteria of Bruce and Goldberg. We studied each cell in a continuous stimulus task, where the monkey made a saccade that brought a recently appearing stimulus into its receptive field. The latency of response in the continuous stimulus task varied from 52 ms before the saccade to 272 ms after the saccade. We classified cells as having predictive visual responses if their latency in the continuous stimulus task was less than the latency of their visual on response to a stimulus in their receptive or movement field as described in a visual fixation task. Thirty-four percent (11 of 32) of the visual cells, 31% (15 of 48) of the visuomovement cells, and no (0 of 20) movement cells showed a predictive visual response. The cells with predictive responses never responded to the stimulus when the monkey did not make the saccade that would bring that stimulus into the receptive field, and never discharged in association with that saccade unless it brought a stimulus into the receptive field. The response in the continuous stimulus task was almost always weaker than the visual on response to a stimulus flashed in the receptive field. Because cells with visual responses but not cells with movement activity alone showed the effect, we conclude that the predictive visual response is a property of the visual processing in the frontal eye field, i.e., a response to the stimulus in the future receptive field. It is not dependent on the actual planning or execution of a saccade to that stimulus. We suggest that the predictive visual mechanism is one in which the brain dynamically calculates the spatial location of objects in terms of desired displacement. This enables the oculomotor system to perform in a spatially accurate manner when there is a dissonance between the retinal location of a target and the saccade necessary to acquire that target. This mechanism does not require an explicit calculation of target position in some supraretinal coordinatesystem.

A phenomenological model of visually evoked spike trains in cat geniculate nonlagged X-cells

1998 ◽  
Vol 15 (6) ◽  
pp. 1157-1174 ◽  
Author(s):  
NICOLAS GAZÈRES ◽  
LYLE J. BORG-GRAHAM ◽  
YVES FRÉGNAC
Keyword(s):  
Visual Information ◽  
Cell Model ◽  
Receptive Fields ◽  
Spike Trains ◽  
Mathematical Framework ◽  
Visual Response ◽  
Visual Responses ◽  
Cortical Cells ◽  
Cortical Receptive Fields ◽  
X Cells

The visual information that first-order cortical cells receive is contained in the visually evoked spike trains of geniculate relay cells. To address functional issues such as the ON/OFF structure of visual cortical receptive fields with modelling studies, a geniculate cell model is needed where the spatial and temporal characteristics of the visual response are described quantitatively. We propose a model simulating the spike trains produced by cat geniculate nonlagged X-cells, based on a review of the electrophysiological literature. The level of description chosen is phenomenological, fitting the dynamics and amplitude of phasic and tonic responses, center/surround antagonism, surround excitatory responses, and the statistical properties of both spontaneous and visually evoked spike trains. The model, which has been constrained so as to reproduce the responses to centered light spots of expanding size and optimal light and dark annuli, predicts responses to thin and large bars flashed in various positions of the receptive field. The switching gamma renewal process method has been introduced for modelling spontaneous and visually evoked spike trains within the same mathematical framework. The statistical structure of the spike process is assumed to be more regular during phasic than tonic visual responses. On the whole, this model generates more realistic geniculate input to cortex than the currently used retinal models.

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