We found 10.9% of V2 neurons exhibited robust orientation selectivity to MBs, and their responses correlated with monkeys' orientation-discrimination performances. (elifesciences.org)
In macaque monkeys, there are a large number of direction-selective (DS) neurons in V2. (elifesciences.org)
From electrode arrays implanted over areas V1 and V2, we recorded neural activity and examined (1) their selectivity to the orientation of MB, (2) their correlation with monkeys' behavioral choice, and (3) neuronal couplings between DS neurons and MB neurons. (elifesciences.org)
For visually guided saccades, neurons in the superior colliculus (SC) emit a burst of spikes to register the appearance of stimulus, and many of the same neurons discharge another burst to initiate the eye movement. (bvsalud.org)
We previously showed that macaque caudal intraparietal (CIP) area neurons possess robust 3D visual representations, carry choice- and saccade-related activity, and exhibit experience-dependent sensorimotor associations (Chang et al. (elifesciences.org)
Superior colliculus2
Controlled cortically by the frontal eye fields (FEF), or subcortically by the superior colliculus, saccades serve as a mechanism for fixation, rapid eye movement, and the fast phase of optokinetic nystagmus. (wikipedia.org)
Trained monkeys performed a two-choice perceptual decision-making task in which they reported the perceived orientation of a dynamic Glass pattern, before and after unilateral, reversible, inactivation of a brainstem area-the superior colliculus (SC)-involved in preparing eye movements. (nature.com)
Macaque monkeys2
We trained macaque monkeys to do orientation discrimination for motion boundaries (MBs) and recorded neuronal response in area V2 with microelectrode arrays. (elifesciences.org)
Here, we used a common experimental design to investigate two areas that bridge the parieto-occipital junction in macaque monkeys: intermediate visual area V3A and the caudal intraparietal (CIP) area. (elifesciences.org)
Visually guided2
We therefore compared amplitude levels and onset times of both spike bursts and LFP modulations recorded simultaneously with a laminar probe along the dorsoventral axis of SC in 3 male monkeys performing the visually guided delayed saccade task. (bvsalud.org)
Saccades can be categorized by intended goal in four ways: In a visually guided saccade, the eyes move toward a visual transient, or stimulus. (wikipedia.org)
Gaze5
Saccades may rotate the eyes in any direction to relocate gaze direction (the direction of sight that corresponds to the fovea), but normally saccades do not rotate the eyes torsionally. (wikipedia.org)
Head-fixed saccades can have amplitudes of up to 90° (from one edge of the oculomotor range to the other), but in normal conditions saccades are far smaller, and any shift of gaze larger than about 20° is accompanied by a headmovement. (wikipedia.org)
During such gaze saccades, first, the eye produces a saccade to get gaze on target, whereas the head follows more slowly and the vestibulo-ocular reflex (VOR) causes the eyes to roll back in the head to keep gaze on the target. (wikipedia.org)
In five healthy human subjects, eye movements about all principal axes of rotation (horizontal, vertical, and torsional) were recorded during voluntary blinks of different durations (as short as possible, 0.83 seconds, and 1.67 seconds) in straight-ahead gaze. (arvojournals.org)
3 measured horizontal and vertical eye movements during blinks at different gaze positions within 10° from straight-ahead gaze. (arvojournals.org)
Rhesus2
Spiking activity along the dorsoventral axis was recorded with a laminar probe as Rhesus monkeys generated saccades to the same stimulus location in tasks that require either executive control to delay saccade onset until permission is granted or the production of an immediate response to a target whose onset is predictable. (bvsalud.org)
Experiments were performed in two hemispheres of two male rhesus monkeys ( Macaca mulatta ) and followed guidelines of the National Institutes of Health with approval by the National Institute of Mental Health Intramural Animal Care and Use Committee. (jneurosci.org)
Movements6
To produce goal-directed eye movements known as saccades, we must channel sensory input from our environment through a process known as sensorimotor transformation. (bvsalud.org)
Saccades are one of the fastest movements produced by the human eye (blinks may reach even higher peak velocities). (wikipedia.org)
The high peak velocities and the main sequence relationship can also be used to distinguish micro-/saccades from other eye movements (like ocular tremor, ocular drift, and smooth pursuit). (wikipedia.org)
Most studies on blink-induced eye movements have been restricted to rotations about the horizontal and vertical axes. (arvojournals.org)
spatial resolution = 0.1 deg and temporal resolution = 60 Hz) was used to non-invasively measure horizontal and vertical eye movements in our patient. (biomedcentral.com)
Sensorimotor2
Sensorimotor associations between 3D orientation and saccade direction preferences were stronger in CIP than V3A, and moderated by choice signals in both areas. (elifesciences.org)
The frontal eye fields (FEFs) participate in both working memory and sensorimotor transformations for saccades, but their role in integrating these functions through time remains unclear. (eneuro.org)
Neuronal1
These saccades are generated by a neuronal mechanism that bypasses time-consuming circuits and activates the eye muscles more directly. (wikipedia.org)
Transformations1
Together, the results explicate parallel representations, hierarchical transformations, and functional associations of visual and saccade-related signals at a key juncture in the 'where' pathway. (elifesciences.org)
Oculomotor3
To further investigate whether the basal ganglia actually influence error-based learning, we reversibly inactivated the oculomotor portion of the substantia nigra pars reticulata (SNr) in two monkeys and tested saccade adaptation. (eneuro.org)
Thus, our data suggest that the oculomotor SNr assists saccade adaptation by strengthening the error signal. (eneuro.org)
Here, we address this question by showing that inactivation of the oculomotor basal ganglia influences the saccade motor learning, a well-established error-based motor learning model. (eneuro.org)
Stimulus1
Saccades to an unexpected stimulus normally take about 200 milliseconds (ms) to initiate, and then last from about 20-200 ms, depending on their amplitude (20-30 ms is typical in language reading). (wikipedia.org)
Fixation2
A saccade (/səˈkɑːd/ sə-KAHD, French for jerk) is a quick, simultaneous movement of both eyes between two or more phases of fixation in the same direction. (wikipedia.org)
Visual Tracking toys and tools to improve visual fixation, visual tracking, visual saccades, in handwriting, reading, and so many functional daily tasks and skills in kids. (otjillian.com)
Amplitude3
In particular, the inactivation facilitated the amplitude decrease adaptation of ipsiversive saccades. (eneuro.org)
Consistent with previous studies, no effect was seen on the amplitude of the ipsiversive saccades when we did not induce adaptation. (eneuro.org)
The amplitude of a saccade is the angular distance the eye travels during the movement. (wikipedia.org)
Behavioral1
and second, there is an established behavioral paradigm that causes an adaptation of saccade size by providing an apparent visual error ( McLaughlin, 1967 ). (eneuro.org)
Task2
In this study, we trained two monkeys to perform an orientation-discrimination task. (elifesciences.org)
Here, we tracked FEF spatial codes through time using a novel analytic method applied to the classic memory-delay saccade task. (eneuro.org)
Contrast1
In contrast, substantial intracollicular processing likely results in a saccade-related spike burst that leads LFP modulation. (bvsalud.org)
Production1
Under certain laboratory circumstances, the latency of, or reaction time to, saccade production can be cut nearly in half (express saccades). (wikipedia.org)
Make1
Error-based motor learning, such as learning to use a robotic arm or make accurate saccades, has been regarded as a cerebellar function. (eneuro.org)
Time1
Intriguingly, the time course of saccade-related activity in CIP aligned with the temporally integrated V3A output. (elifesciences.org)
Small saccades5
We observed a topography of saccade direction and amplitude consistent with findings in macaques and humans: small saccades in ventrolateral FEF and large saccades combined with contralateral neck and shoulder movements encoded in dorsomedial FEF. (jneurosci.org)
Before characterizing the neurophysiological foundations underlying this relationship between the spatial and temporal aspects of saccades, we tested the triggering of small saccades in the male rhesus macaque monkey. (bvsalud.org)
Using a variety of behavioral tasks exercising visual and nonvisual guidance of small saccades, we found that small saccades consistently require more time than larger saccades to be triggered in the nonhuman primate, even in the absence of any visual guidance and when valid advance information about the saccade landing position is available. (bvsalud.org)
We also found a strong asymmetry in the reaction times of small upper versus lower visual field visually guided saccades, a phenomenon that has not been described before for small saccades, even in humans. (bvsalud.org)
We found that small saccades always take longer, on average, than larger saccades to trigger, regardless of visual and cognitive context. (bvsalud.org)
Fastigial4
The caudal fastigial nuclei (cFN) are the output nuclei by which the medio-posterior cerebellum influences the production of saccades toward a visual target. (bvsalud.org)
We further tested this hypothesis by studying, in two head-restrained macaques, the effects of unilaterally inactivating the caudal fastigial nucleus on saccades toward a target moving vertically with a constant, increasing or decreasing speed. (bvsalud.org)
We explain how this correlation corroborates the bilateral hypothesis and provide arguments against the suggestion that the instantaneous saccade velocity would somehow be "encoded" by the discharge of Purkinje cells in the oculomotor vermis.NEW & NOTEWORTHY Besides causing dysmetric horizontal saccades, unilateral inactivation of caudal fastigial nucleus causes an ipsipulsion of vertical saccades. (bvsalud.org)
Simulating the shaping of the fastigial deep nuclear saccade command by cerebellar Purkinje cells. (neurotree.org)
Rhesus macaqu1
Our results provide an important catalog of nonhuman primate oculomotor capabilities on the miniature scale, allowing concrete predictions on underlying neurophysiological mechanisms.NEW & NOTEWORTHY Leveraging a multitude of neurophysiological investigations in the rhesus macaque monkey, we generated and tested hypotheses about small-saccade latencies in this animal model. (bvsalud.org)
Velocity1
Velocity-based algorithms are a common approach for saccade detection in eye tracking. (wikipedia.org)
Ocular4
The high peak velocities and the main sequence relationship can also be used to distinguish micro-/saccades from other eye movements (like ocular tremor, ocular drift, and smooth pursuit). (wikipedia.org)
During such gaze saccades, first, the eye produces a saccade to get gaze on target, whereas the head follows more slowly and the vestibulo-ocular reflex (VOR) causes the eyes to roll back in the head to keep gaze on the target. (wikipedia.org)
Skew deviation is characterized as an acquired vertical misalignment of the eyes that is not due to any single muscle or ocular motor nerve. (eyewiki.org)
Westheimer and Blair coined the phrase ocular tilt reaction in 1975 after a series of experiments of brainstem stimulation on monkeys and determined that the ocular tilt reaction and skew deviation described a singular pathology. (eyewiki.org)
Reaction1
Under certain laboratory circumstances, the latency of, or reaction time to, saccade production can be cut nearly in half (express saccades). (wikipedia.org)
Experiments1
Over the past 40 years, most of our knowledge regarding the neural processes in the FEF has come from experiments in awake, behaving macaque monkeys. (jneurosci.org)
Common1
By subtracting the effects on contralesional (hypometric) and ipsilesional (hypermetric) horizontal saccades, we find that this net bilateral effect is strongly correlated with the ipsipulsion of vertical saccades, corroborating the suggestion that a common disorder affects all saccades. (bvsalud.org)
Moving target1
This study is the first to quantitatively describe this ipsipulsion during saccades toward a moving target. (bvsalud.org)
Visual2
[14] Their entire visual field is tilted together, but due to the visual orientationcues present in everyday life, they can maintain accuracy of the true vertical orientation. (eyewiki.org)
1 In 22 states in the USA, people with HH do not meet the minimum horizontal visual field requirement for driving (e.g., 120° in Massachusetts), 2 yet many continue to drive, 3 albeit illegally, to maintain independence and quality of life. (arvojournals.org)
Direction1
Saccades may rotate the eyes in any direction to relocate gaze direction (the direction of sight that corresponds to the fovea), but normally saccades do not rotate the eyes torsionally. (wikipedia.org)