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)
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)
Visually guided2
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)
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)
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 head movement. (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)
Possible PSP requires the presence of a gradually progressive disorder with onset at age 40 or later, either vertical supranuclear gaze palsy or both slowing of vertical saccades and prominent postural instability with falls in the first year of onset, as well as no evidence of other diseases that could explain these features. (neurology.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)
Stimulus2
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)
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)
Movements3
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)
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)
Task1
Here, we tracked FEF spatial codes through time using a novel analytic method applied to the classic memory-delay saccade task. (eneuro.org)
Movement2
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)
The amplitude of a saccade is the angular distance the eye travels during the movement. (wikipedia.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)
Vertical1
2 described the horizontal and vertical trajectories of the human eye during the entire period of voluntary and reflexive blinks. (arvojournals.org)
Eyes1
During the initial phase of voluntary eyelid closure, the eyes move in a three-dimensional direction that is consistent with a pulselike innervation of the inferior rectus muscle. (arvojournals.org)
Visually guided saccade2
8 In particular, FEF is involved in saccades generation, which are internally triggered toward a target already present (visually guided saccade), not yet present (predictive saccade), and no longer visible (memory-guided saccade) or located in the opposite direction (antisaccade). (nature.com)
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)
Saccadic1
Based on this, we propose a novel benefit for the modulation of saccade trajectories by the oculomotor system: minimizing the saccadic error in sequential saccades. (nih.gov)
Oculomotor2
The planning and execution of sequential saccades can overlap in time, and abrupt changes in neural activity in the oculomotor system can alter the normal trajectory of saccades. (nih.gov)
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 head movement. (wikipedia.org)
Amplitude3
The results showed modulation of saccade curvature by the direction and amplitude of both the preceding and following saccade: saccade curvature is modulated in the direction of preceding saccades and away from the direction of following saccades. (nih.gov)
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)
The amplitude of a saccade is the angular distance the eye travels during the movement. (wikipedia.org)
Sequence2
In two separate psychophysical experiments, subjects were instructed to make a sequence of two saccades. (nih.gov)
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)
Pursuit1
the frontal eye field (FEF) and its role in saccade and pursuit eye movement control, the supplementary eye field (SEF) and the dorsolateral prefrontal cortex (dlPFC). (nature.com)
Direction2
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)
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)
Target2
Specific pre-target oscillatory (alpha rhythms) and transient activities occurring in posterior-lateral parietal cortex and occipital cortex also characterise express saccades. (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)
Larger1
Moreover, larger preceding and following saccades have stronger effects on curvature. (nih.gov)